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Shipping Container Swimming Pool. Shipping Container Design. Shipping Container Interior. Container Architecture Container Buildings. The reduction in SVI as a result of sodium aluminate addition was very dramatic. It should be noted that throughout the Phase I operation, the SVI's for each of the tanks were lower than those normally expected in a conventional activated sludge plant treating domestic wastes.
Barth and Ettinger 2 report sludge density indexes SDI for pilot plant operation using conventional activated sludge and sodium aluminate addition to the aerator of 0. I sodium aluminate addition. The solids age during the period of no chemical addition and the period of alum addition averaged 1.
The solids age during the sodium aluminate runs was appreciably higher approximately 2. The higher solids age during the aluminate studies was a result of the lower flows and loadings experi- enced during this period. Sludge Production Sludge production is a very important consideration in wastewater treatment because of the problems of solids handling and ultimate dis- posal.
Insufficient data were collected during the period of no chemical addition prior to the alum runs to permit a significant evaluation of the waste sludge production from the units under con- ventional operation. The data presented in Table 3 indicate that a significantly greater volume and weight of waste sludge was produced from the use of alum than from the use of sodium aluminate.
These values may be atypical since organic loadings and influent phosphorus concentrations were lower during the period of sodium aluminate addi- tion than they were during the alum studies. This reduction would also reduce the amount of solids produced, hence direct comparison between the sludge production figures for the two precipitants is dif- ficult. Jenkins and Menar 14 reported a weighted mean value of 2.
The percentage phosphorus increased greatly as a result of chemical addition as shown by the data in Table 3. The observed higher percentage during the sodium aluminate runs seems reasonable since the amount of volatile solids produced was much less while the amount of phosphorus removed was nearly the same as with alum addition.
These data show the use of aluminum sulfate resulted in higher removals of BOD, COD and phosphorus than were realized with sodium aluminate. Because of this, alum was selected for use during Phase II of the project. It should be noted that the pH values observed during both the alum and the sodium aluminate studies were well above the optimum reported in the literature for phosphorus removal using aluminum as the precipitant.
Therefore, lower effluent filtered phosphorus concentrations would be achieved if the pH of the system were lowered in accordance with the findings of Eberhardt and Nesbitt 9. Full plant scale evaluation of pH control was not a part of this study so this question must be resolved at another time. However, some data on additional pH observations made during Phase II will be discussed later and will reflect on this.
It should not be concluded from the data shown that alum will be superior to sodium aluminate with all wastewaters. Ratio filt. Chemical addition at effluent end of aeration tank only. Q Data from Tank 1 only. Average pH values for the trickling filter effluent were 7.
Since it is the pH after chemical addition which is important, it should be noted that alum lowers the pH whereas sodium aluminate raises it. The higher effluent pH's observed with use of sodium aluminate are most likely the primary reason for the lower phosphorus removals experienced with this chemical in this study. Brenner 4 also discusses the relative advantages of using sodium aluminate and alum when both chemicals were added at the head end of the aeration tank.
His observations that poorer fine floe capture occurs as the pH approaches 6 is more likely due to conditions created by adding the chemical at the head end of the aeration tank than it is strictly to pH although pH is also important. Zenz and Pivnicka 52 also observed a carry-over of fine floe described by them as "milky white" and observed that the amount of floe increased with increasing alum dosages which would decrease the pH.
Since they also added the precipitant at the head end of the tank, it is likely that this floe carry-over could have been reduced or prevented by changing the point of chemical addition to the effluent end of the tank. Recht and Ghassemi 29 have shown that the reaction between aluminum and ortho- phosphate is very rapid and may be instantaneous. Therefore, adequate reaction time for phosphate removal should exist when adding the chemi- cal into the effluent line from the aeration tank.
The reasons for the "carry-through" of phosphorus which was experienced during the sodium aluminate studies and with alum when the chemical was added at points other than at the effluent end of the aeration tank and as noted by others are still not completely understood. It is believed to be a function of: 1 pH, 2 solids age, and 3 point of chemical addition. Since it does result in significantly higher effluent phos- phorus concentrations than would otherwise be expected, additional study during Phase II was undertaken in an attempt to resolve some of the questions regarding this phenomenon.
These observations will be reported elsewhere. As indicated earlier, in the chemical feeding system employed in this study, liquid chemical was stored in a PVC lined wooden tank and diaphram chemical feed pumps were used to meter the chemical.
No problems with chemical handling were experienced during the Phase I studies. Sodium aluminate is much more viscous than alum and could cause handling difficulties during cold weather in some instances. All of the aluminate runs were conducted during warm weather so it was impossible to assess cold weather operation.
The period of study using alum began in January and no unusual problems were experienced during cold weather operation. In addition, several aspects of the operation which were not investigated during Phase I were researched briefly during Phase II in an attempt to guide future research into detailed areas of study not included herein or yet generally understood. The plan of operation and plant operational procedures for Phase II studies were as outlined earlier for Phase I, Aluminum Sulfate Studies, except as noted subsequently.
In contrast to the procedure used during Phase I, variations in the phosphorus concentration as well as flow variations were incorporated into the chemical feed rate calculations during Phase II. It should be noted again that the effect of the phosphorus variation was very much less than that of flow variation but that these results are probably atypical.
Sampling schedules and analyses of samples were as reported for Phase I except that data on alkalinity, calcium, magnesium, and color were collected routinely whereas data on aluminum and sulfate were collected only at infrequent intervals. General Operation Phase II operation began on August 21, with the addition of liquid aluminum sulfate alum into the effluent channel from Aeration Tank No. Aeration Tank No. Operation over a one year period was accomplished in order to furnish data which would reflect operating capabilities of the chemical-bio- logical process under varying operating conditions including those resulting from changing loads, student populations, weather, and pro- cess modification or adaptation as a result of chemical addition over extended periods.
For the pur- poses of the Phase II studies it was desired to produce an effluent which contained not more than 0. Allowing for dilution, this then should meet the water quality standards which have been established. Subsequent to the study, the Board now uses the 0. Design average flow is 1. Most of the low flow days occurred during term breaks when students were absent from campus although Sunday flows were often less than design average even when students were on campus.
The problem of flow variation was par- ticularly severe during the Spring term at the University March 30 - June 13, These extreme fluctuations in flow made evalu- ation of the effects of the chemical-biological process on the various parameters studied difficult and it was impossible to separate out completely the effects of varying flow in analyzing the results ob- tained.
In an attempt to illustrate the effect of flow data presenta- tion for Phase II operation has been broken down into three classifi- cations: 1 data collected when daily flows did not exceed 1. The daily flow was greater than 1.
Both median and mean values have been presented so as to reflect bet- ter the effect of varying flow and the resulting extreme values which occurred. Considerable variance was observed in the data for most of the parameters measured but it is believed the results which are pre- sented herein do reflect the operating capabilities of the system. Due consideration should be given in the interpretation of results to the hydraulic overload that occurred on numerous occasions.
The mean flow for this category was 0. Peak rates of flow did exceed design at different periods of the day on many occasions but at these relatively low total flows they did not affect the results observed significantly. The results are generally similar to those observed during the aluminum sulfate studies of Phase I and are con- sidered to be typic'1.
As expected, little oxidized nitrogen was found in the trickling filter effluent on most occasions. The difference between the median and mean values and the wide range of values observed suggest the flow and tem- perature variations which occurred had more influence on nitrification than on other processes involved. A 68 Alum addition to effluent end of tank. These data also suggest that even though total daily flows were below design average, the flow rate fluctuation throughout the day is sufficient to cause widely varying effluent characteristics.
While other factors can and do influence treatment plant efficiency, it was felt that flow variation was the most significant factor accounting for the major portion of the vari- ability observed in plant performance during this study. Comparison of the median values for suspended solids from each of the two tanks indicate that considerably improved capture of suspended solids can be expected from the chemical-biological system.
However, when the mean values are compared, no such conclusion can be reached. It was noted earlier that the total solids which must be carried in the chemical-biological system are much higher than those carried in a conventional activated sludge system because of the large amount of nonbiological solids present in the form of precipitated phosphorus.
This greater amount of solids which must be removed in the final set- tling tanks makes hydraulic loading even more critical in this system and probably accounts for the relatively small differences observed between median and mean values for Tank No.
The same conclusions can be drawn from the COD data although the noted improvement achieved by the chemical-biological unit is not as great. The nitrogen data in Table 6, Part B, also show a lower degree of nitri- fication for the chemical-biological system similar to that which was observed during the Phase I studies. The difference was not as great as observed during Phase I which suggests again the importance of flow and solids age as parameters affecting nitrification in activated sludge units.
Phosphorus Removal The effluent phosphorus data presented in Table 6, Part C, also reflect the variability in results resulting from flow fluctuations even when all flows are within design average values. As noted earlier, low flows often occurred on Sundays even when a normal student population was on campus. This resulted in an overdose of alum in these instances which did not adversely affect results but was uneconomical in terms of chemical usage. Filtered effluent phosphorus removals were again excellent.
The mean values reported for both ortho and total phosphorus include data ob- tained during periods when flows were changing and feed rate adjust- ments were being made. Figure 8 shows the statistical dis- tribution of effluent total phosphorus concentrations for Tank No.
Later discussion will attempt to identify those operating problems and procedures which would optimize the economy and reliability of the process. The data on unfiltered effluent phosphorus concentrations also show considerable variation for the reasons given above. Figure 9 presents the statistical distribution of these data for Tank No. These data also are not normally distributed throughout the range of observation so that statistical inferences from the data must consider this.
No attempt was made to normalize the data or to otherwise modify or uti- lize sophisticated statistical techniques in analyzing the data. The mean daily flow for this category was 1. Peak rates of flow during the day would often go as high as 1.
Data on the various parameters Indicate heavier loadings on the plant along with the increasing flow but no other significant differences from earlier observations. These data show less variability than those observed at the lower flows.
However, the range of flow observed was also much less in this category. Median Mean Dev. This effect is most apparent in the comparison of suspended solids data and in the differences between median and mean values for solids, BOD and COD. Figure 10 shows the variation in effluent suspended solids, flow and unfiltered effluent orthophosphate which can be considered typical of that which was ob- served almost daily particularly during the Spring Term The median values for effluent suspended solids show that although the solids loss from Tank No.
However, the significant point is the con- tradiction of the results observed at the lower flows where comparison of medians showed significant improvement in removal of suspended solids as a result of chemical addition. Comparison of means reflects the extremely high loss of solids from Tank No.
The mean values again reflect the influence of high suspended solids which also increases the effluent BOD and COD and results in an appar- ent advantage for the untreated system. These data also show that flow has relatively less influence on the untreated system than on the treated system when they are compared with the data observed for flows below design average. The higher flows and resulting lower solids age observed also effected a reduction in nitrification in both units as can be seen in the com- parison of data in Table 7 with that reported in Table 6.
The lower degree of nitrification observed for Tank No. Phosphorus Removal The effluent phosphorus data presented in Part C, Table 7, show very good removal of phosphorus on filtered effluent samples but the re- movals are significantly less than those observed at the lower flows. Figure 11 shows the statistical distribution of the phosphorus data for Tank No. The unfiltered effluent phosphorus removals were significantly higher than those observed from Tank No.
Figure 12 shows the statistical distribution of the unfiltered effluent phosphorus data for this category. During this period, one occasion occurred where chemical addition was inter- rupted for about twelve hours when heavy snows prevented needed deliv- ery of alum. On at least one other occasion a plant operator failed to make a scheduled feed pump rate change and underdosing occurred for a period of about three'hours.
These are the only known occasions during the one year run when chemical addition was interrupted or re- duce'd from scheduled feed rates except for brief periods of less than one-hour duration to permit maintenance work on pumps and chemical feed lines.
These data reflect results obtained on these occasions as well as those obtained during periods of flow adjustment when major changes in student population were occurring. All data included in Table 10 were used also in the data analyses for Tables 8 and 9. Influent Waste Trickling Filter Effluent As noted previously, the influent waste is characteristic of domestic wastewater and presents no unusual problems in treatment.
The mean daily flow for all days on which data were collected was 0. Prior discussion has pointed out the variability of flow experienced and the effect of this variation on results obtained. The influent wastewater has a moderately high alkalinity and approxi- mately equal calcium and magnesium content.
The phosphorus data for filtered samples frequently showed higher values for orthophosphate than for total phos- phorus on both influent and effluent samples. There was no apparent explanation for this observation which has also been noted by others 3. General Effluent Quality Because of the extremely wide variation in results obtained for most of the parameters measured as a result of hydraulic overloading, the median values reported offer a better basis for comparison than do mean values.
Therefore, unless otherwise noted the ensuing discussion will involve comparison of reported median values. General Performance and Effluent Quality Tank lb fl. Regres- sion analyses of the data yielded the following equations for the lines of best fit: Tank No. Figure 14 shows the relationship between unfiltered BOD and effluent solids for both units.
A better correlation could have been achieved if sufficient data had been available to compute the insoluble BOD and these values used instead. Acknowledging this deficiency and the wide variability of data, these curves and the resulting regression equa- tions also indicate that lower effluent BOD can be expected from the chemical-biological system.
These curves also show the importance of suspended solids removal if optimum BOD removal is to be achieved. The nitrogen data show a significant difference in the degree of nitri- fication which occurred in the chemical-biological system compared with that of the control unit.
Table 9 shows the average results of nitro- gen analyses performed on three occasions on samples of mixed liquor to see if the difference observed in effluent samples could be seen in samples taken prior to alum addition. The same difference was apparent indicating that alum addition does in some way reduce nitri- fication under the conditions of operation experienced during these studies.
As expected, the reduction in alkalinity in Tank No. Brenner 4 reports a reduc- tion in alkalinity from to 67 mg CaC03 as a result of alum addi- tion. This is significantly greater than the reduction observed in this study using mean or median values but such large reductions were observed on occasions where an overdose of alum occurred.
Since Brenner did not include data on alum dosages, direct comparison is difficult. Some increase in calcium in the effluent from Tank No. Menar and Jenkins 23 have postulated the release of calcium during activated sludge treatment. A possible ex- planation for the observed increase in calcium in Tank No. This mechanism of phosphorus removal, i. Color removal was significantly higher as a result of alum addition. On days where flows were low, the effluent from Tank No. Only a limited amount of data on aluminum and sulfate concentrations were collected during Phase II operation.
The sulfate data for Phase I Run Code III Table 1 showed the sulfate concentration of the trickling filter effluent and the final effluent during the period when no chemical was added to be only about one-half that observed for Trickling Filter and Tank No.
There is no apparent explanation for this difference. The sulfate concentration of the alum treated unit was virtually the same as observed during Phase I studies. Each pound of aluminum added in the form of filter alum adds 5. If the observed increase in sul- fate in the effluent from the treated unit is correlated with the mean flow 0.
Phosphorus Removal The effluent phosphorus data presented in Part C of Table 8 confirms the observations which have already been made regarding phosphorus removal. These data show close agreement with the results obtained by Eberhardt and Nesbitt 9 , particularly for the relationship between insoluble phosphorus and effluent inorganic solids.
The comparable data from their study shows approximately 9. Figure 17 shows the statistical distribution of the unfiltered efflu- ent total phosphorus for all data obtained. As was the case in Phase I, volatile solids data were not corrected for apparent volatile solids production due to volatilization of inorganics during the analysis procedure. The sludge volume index data show there was no decrease in SVI as a result of alum addition over those observed in the control unit.
Eberhardt and Nesbitt 9 observed a significant decrease in SVI as a result of mineral addition into the high rate system used in their study. However, the mean SVI of 63 for the control unit in the study reported herein is considerably lower than normally expected for a conventional activated sludge plant treating domestic wastes. The highest values recorded during the study were 96 and for Tank No.
The sludges from both tanks settled very readily as can be seen in Figure This settling rate is particularly significant since even sludges with such excellent characteristics could not be handled under the conditions of hydraulic overload experienced without causing problems. As noted earlier, Tank No. The average solids age of the chemical-biological system was 1,58 days which was significantly lower than the average of 2.
This is probably most significant as it affects nitrifica- tion since BOD and COD removals were generally better in the chemical- biological system whereas nitrification was greater in the control. Sludge Production As indicated previously, solids handling is an important consideration in any wastewater treatment scheme. Hence, the solids production from the chemical-biological process is of prime concern.
The data pre- sented in Table 10 on waste sludge production were correlated with flow mean flow for Phase II and are shown in Table Table The results of Phase II operation showed that for the system studied approximately twice as many pounds of total solids and one and one-half times as many pounds of volatile solids are produced in the chemical-biological system as in the control.
The predicted and observed results show very close agreement for the sludge production from Tank No. As pointed out earlier, the volatile solids test procedure used undoubtably reports results which are too high because of the probable volatilization of aluminum hydroxy- phosphate compounds. Eberhardt and Nesbitt 9 in referring to the work by others reported weight losses of as high as Recht and Ghassemi 29 showed weight losses of If the ob- served results for the volatile solids produced in Tank No.
This difference probably results from the initial assumption above that aluminum reacts only with phosphate and hydroxide ions. This is probably not true and the other reactions if known could be incorporated into the calculation and could result in better correlation of results. Several samples of waste sludge were subjected to X-ray diffraction analysis in an attempt to Identify the precipitates which were formed but all samples showed the precipitates to be amorphous, hence identi- fication was impossible.
Other workers have reported similar results in their attempts to Identify the compounds Mixed Liquor Phosphorus The percentage of phosphorus in the mixed liquor from the chemical- biological system was about twice as great as that observed in the control system.
Considerable variability was observed in this para- meter in both systems. This variability was thought to be due in a large part to the difficulty in analyzing sludge samples for total phosphorus because of the high dilutions which must be made. The phosphorus content of the control system of 3. It is also significantly higher than the 2. Brenner 4 reported a phosphorus content in the waste activated sludge of 3.
Earth and Ettinger 2 reported a value of 3. A very limited amount of data collected during the latter part of Phase II are included in Figure 20, also taken from Menar and Jenkins These data further indicate that the observed percent- age of phosphorus in the control system was not unusually high. Perhaps the most interesting observation in the activated sludge data was the difference in the filtered total phosphorus concentrations in the mixed liquor from each of the two units. Mixed liquor samples were collected ahead of the point of chemical addition so it was ex- pected the filtered phosphorus values would be approximately equal in each tank at the point of collection.
The much lower values observed in Tank No. However, continuous addition of alum is apparently necessary to keep effluent phosphorus concentrations low since they rose very rapidly when chemical addition was interrupted. Recht and Ghassemi 29 reported that freshly precipitated aluminum hydroxides possess little capacity to precipitate phosphates. The aging of the aluminum hydroxy-phosphate precipitates in the chemical-biological system during the time they are retained in the aerator may account for the observed difference in filtered total phosphorus concentrations between the two tanks.
In an attempt to apply corrective measures against this effluent degradation, a series of polymer additions were made into the influent to Final Settling Tank No. The polymer selected for use on the basis of jar tests was a moderately cationic flocculant Nalco Samples of mixed liquor taken from the influent channel prior to and following polymer addition were allowed to settle in ml cylinders for visual comparison of settling rates and effluent clarity.
The initial dosage of 0. The floes appeared to have a more grainy texture after polymer addition. The settling characteristics in the basin may have been better than those shown in Figure 21 since the floe would have had some additional mixing and time to build subsequent to the point of sampling.
Visual inspection of the tank during periods of peak flows did not show any noticeable benefit from polymer addition. Polymer dosages were increased to 0. Because of limited storage capacity for polymer, polymer addition was restricted to those hours of the day when solids losses were heaviest, usually from a. Although polymer addition did not significantly reduce the loss of solids from Tank 1, the resulting settled effluent was more clear and sparkling than normal.
Figure 22 shows the typical variation in effluent suspended solids from Tank 1 during periods of hydraulic overload both with and without polymer addition. These data were taken on two different days so the flow patterns and hence the pattern of solids loss are not the same but similar.
The data show conclusiv- ely that, even with polymer addition, the effluent suspended solids were too high for direct discharge to the receiving stream. Since this was intended to be only a preliminary investigation of the effects of polymers on the reduction of suspended solids, the investi- gation was terminated after four days of operation because of the poor results obtained. For the purposes of these studies, samples of the mixed liquor from Tank No.
The initial pH's of the samples were recorded and the pH's of each of five samples were adjusted to the desired test pH with addition of 0. The samples were mixed during the pH adjustment step and were then allowed to settle for 30 minutes. Phosphorus, turbidity and pH determinations were made on filtered and unfiltered supernatant samples from each jar. Table 12 shows the summary results from these studies. As pointed out earlier, a haze or "carry-through" of what is thought to be very finely divided "aluminum phosphate" occurs when the pre- cipitant is added at the head end of the tank.
The data in Table 12 suggest this is partially a function of pH since lower effluent insolu- ble phosphorus and filterable turbidity results were obtained with a reduction in pH see Figure The pH adjustments were made after alum addition and mixing in the aeration tank so the fine precipitate should have been present in the samples brought back to the laboratory. Additional study would be needed to determine if this has any practical significance in terms of operating performance and proce- dures.
A series of in situ pH measurements were made in each of the two aeration and settling tanks to determine actual pH profiles through the tanks during normal operation. Figure 24 shows the pH profile during normal operation with alum addition into the effluent channel from the aeration tank as described earlier.
These data show a very severe depression of pH immediately following the alum addition pH 6. The pH stays about 5. This pH is near optimum for phosphorus removal and is the result of the alum addition alone. These results were significantly different from the effluent pH's observed during regular collection of.
Further investi- gation showed the pH of the sample increases with time apparently as a result of loss of entrained C The sample which showed a pH of 5. The results of the jar tests reported in Table 12 also show this increase in pH upon standing. Therefore, the composite samples collected on a routine basis did not accurately reflect the pH in the final tanks but rather some sort of equilibrium pH depending on the length of time the sample had been standing.
This same obser- vation was made in the data from Tank No. The sample from Tank No. Figure 25 shows the pH profile data taken in a similar manner with alum addition at the influent end of the tank. These data show no measureable reduction in pH occurred as a result of alum addition under these operating conditions. The vast buffering capacity of the mixed liquor in the tank with the dispersion which occurred was able to buffer the alum addition at this point.
In contrast, the relatively slow dispersion which occurred when alum was added into the effluent channel was not sufficient to buffer the system. Recht and Ghassemi 29 also showed in their work on precipitation of phosphorus with aluminum that effluent residual turbidity is related to pH. They showed a minimum residual turbidity at about pH 5.
This observation may also help to explain the "carry-through" which occurred when alum was added at the influent end of the aerator since the pH then was about 7 through the aerator and final clarifier whereas it was decreased to about pH 6 through the final clarifier when alum was added into the effluent channel.
A series of samples were analyzed by means of an atomic absorption spectrophotometer but no significant differences were ob- served between effluent samples obtained with alum addition at the influent end. Preliminary particle size determinations with an opti- cal microscope did not show any discernible difference between efflu- ents even with use of 0.
This similarity would suggest that many of the particles which make up the haze or "carry through" are extremely fine pass through a 0. Because of limitations of time and the general lack of success in identifying or adequately characterizing the "carry-through," it was decided to abandon such attempts for the purposes of this project.
Chemical addi- tion during this period was at the influent end of the aeration tank for the purposes of a separate microbiology study and because of this the pH of the system following alum addition was higher than that ob- served during alum addition into the effluent channel as reported above.
The effluent from the chemical-biological system during this period was more turbid than reported previously. However, on three occasions the effluent was visibly less turbid than usual and on all three occasions the pH of the mixed liquor sample was between 5. Table 13 presents summary data for this period Aug. The data on oxidized nitrogen show no significant dif- ference between Tank No.
These data can be compared with the results reported in Table 6, Part B, where the difference in oxidized nitrogen between Tanks No. It would appear that either the higher solids or the chemical addition into the influent end of the aeration tank or both negated the previously exhibited inhibitory effect of alum addition or nitrification.
However, it is not possible from the data to determine whether the higher mixed liquor suspended solids and resulting higher solids age or the change in the point of alum addition was responsible for the change observed. It is the writer's opinion that the lower pH and greater pH shock which occurred with alum addition into the effluent channel was primarily responsible for the apparent inhibition of nitri- fication that was observed during Phases I and II.
Flow - MGD 0. However, it probably did not have a significant role in eliminating the inhibitory effect of alum addition. Insufficient data were available to calculate the respective solids ages for this period. Termination of project opera- tion did not permit collection of comparative data with alum addition into the effluent channel.
Comparison of the phosphorus data in Table 13 with similar data in Table 6, Part C, illustrates the deterioration which occurs in efflu- ent quality when alum addition is at the influent end of the aeration tank. These data show that average removals of unfiltered effluent total phosphorus decreased from This difference is most likely due to the "carry-through" which occurs with alum addi- tion into the influent end of the aeration tank.
The effect of fil- tered effluent phosphorus concentrations is much less since much of the mass of the "carry-through" is removed during the filtration step. Effluent Fertility Since the reason for removing phosphorus from wastewaters is to reduce the fertility of the effluent, samples of trickling filter effluent and effluents from the control unit and the chemical-biological system were subjected to the Provisional Algal Assay Procedure PAAP 28 by personnel from the FMC Corporation, Central Research Department, Prince- ton, New Jersey Selenastrum capricornutum was used as the test organism and samples from Upper Spring Creek above the point of efflu- ent discharge were used as the dilution medium for the tests.
USC water with 1. Additional experiments showed that addition of dibasic potassium phosphate K2HP04 or sodium phosphate Na2HP04 to Tank No, 1 effluent to the same phosphorus concentration observed in Tank No. The studies indicated that the lack of growth in the Tank No. While very limited in scope, these preliminary studies did show a sig- nificantly lower growth potential for effluents from Tank No. Further, spiking of Tank No.
Operation of the chemical-biological system and the control unit were continued until December 1, to permit continued col- lection of data for a satellite project on the microbiology of the two systems and the special studies described above. The suggestions and recommendations con- tained herein are applicable for new treatment facilities as well as for modifications to existing plants.
Some of the data on wastewater flows and characteristics will, of course, have to be estimated for new installations. Therefore, flexibility should be incorporated into the design so that reasonable changes from predicted values can be incorporated into plant operation without adversely affecting the results obtained. The following parameters must be evaluated in order to achieve an economical design that will provide the flexibility and capability to meet the effluent requirements established for the plant: 1.
Flow - design average with due consideration of peak flow rates and daily, weekly and monthly variations. Phosphorus concentration - variation in concentration with time is important as are the relative amounts of ortho and complex; soluble and insoluble phosphorus. If pH is 7. Sulfate - addition of appreciable amounts of sulfate to wastewaters already high in sulfate concentration or where effluents are to be discharged to stream used for potable water sources may be undesirable.
In this event, sodium aluminate would probably be the chemical of choice. Chemical Handling and Feeding Liquid chemical handling and feeding systems are generally easier to operate and maintain than are dry feed systems. However, transporta- tion costs and inaccessibility to liquid chemical sources may dictate use of dry chemicals in some instances.
Provision should be included for measuring the amount of chemical fed. The point of chemical addition should be located as near to the efflu- ent end of the aeration tank as is practical. Because of the severe pH shock which occurred when alum was added directly into the effluent channel during this study, it is suggested that addition be made into the aeration tank in order to take advantage of the greater buffering capacity at that point.
Some deterioration in effluent quality can be expected as the point of addition is moved toward the influent end. Excessive suction head on the chemical feed pumps should be avoided to prevent siphoning of chemical through the feed pumps at high tank levels. Pump manufacturers should be consulted for suction lift characteristics of their pumps and maximum suction heads which can be tolerated for the chemical involved. Exposed chemical feed lines and storage tanks should be insulated for cold weather operation.
Process Control It is highly desirable for the chemical feeders to be paced from in- fluent flow meters so that chemical feed rate adjustment is more responsive to flow changes. This is important both for economy of operation but perhaps even more to avoid underdosing which can result in intolerable increases in effluent phosphorus concentrations. Since a proven reliable means for automated phosphorus analysis of effluents which could be used in compound loop control of chemical feed is not presently available, it is recommended that phosphorus concentration variations be incorporated into the chemical dosage calculations and the flow - feed rate schedule to compensate for the variations as much as possible.
It is suggested that a planned slight overdose be practiced since this will help to ensure high quality effluent where this is required. Where unusually high peaks occur, consideration should be given: to even lower overflow rates. In some instances it may be desirable to provide influent equalizing storage to dampen out surges.
This would be of assistance also in optimizing chemical feed since many of the variations in flow and concentration which otherwise occur would be eliminated. Severe cases of hydraulic overloading may re- quire construction of new settling tanks or surge tanks to alleviate the problem. Effluent Filtration It will usually be necessary to provide filtration of effluent in order to meet very stringent phosphorus removal requirements.
Filtra- tion does provide a safety factor to protect the stream in the event of heavy solids losses from the clarifiers. Various filter devices are available and may be evaluated by the designer for the particular application involved. Solids Handling No special solids handling equipment or requirements are necessary for handling and disposal of the sludges resulting from chemical-biological treatment.
Flexibility in pumping units should be sufficient to handle the greater weight of solids and volumes of sludges which result from chemical-biological treatment in instances. Sludge weights approxi- mately twice those obtained without chemical addition can be expected. Dewatering and disposal of the chemical-biological sludges should not present any unusual problems.
These sludges are generally more easily dewatered than are biological sludges and may be handled by. It is unlikely that recovery of the precipitating chemical will offer any economic advantage except under unusual circumstances. Process Control It is recommended that filtered orthophosphate in the influent waste be used as the basis for process control.
The orthophosphate test pro- cedure is rapid and relatively simple to perform compared to the pro- cedure for total phosphate. However, it is recommended that operating data from each individual plant be reviewed regularly and adjustments in dosage be made as needed to achieve the particular degree of removal required.
Once the relationship between ortho and total phosphorus has been determined for a given plant, the orthophosphate test can be used to predict effluent total phosphorus values with sufficient accuracy for control purposes. Control of mixed liquor suspended solids must take into consideration the much lower percentage of volatile solids in the chemical-biologi- cal system.
The mixed liquor volatile suspended solids should be maintained at the necessary level to achieve the desired organic loadings. Once the system has reached a balance, control can be based on total suspended solids with regular checks on volatile solids so that any changes can be incorporated into sludge wasting schedules.
Operators should check the amount of chemical actually fed each shift to detect underfeed or overfeed as soon as possible. Unless the chemical feed lines have a constant slope to the point of application, they should be checked frequently for entrapped air and vented as required. Return of waste sludge from the chemical-biological system to the pri- mary settling tanks during this study resulted in better concentration of primary sludges in the withdrawal hoppers.
This reduces the amount of water which must be handled in the solids handling process and hence can be of advantage where piping flexibility permits. Maintenance Some additional corrosion can be expected as a result of the lower pH's which may occur in the chemical-biological system when alum is used. Visual comparison in September of collection mechanisms in the two final clarifiers used in the study revealed some additional cor- rosion occurred as a result of alum addition.
However, the treatment plant foreman did not feel it was excessive for the length of time the units had been in operation without being taken down for maintenance. The most noticeable difference was in the color of the corrosion pro- ducts. Those from Tank No. This corrosion problem can be taken care of by proper selection of protective coatings. Less growth of slimes on weirs and tank walls was noted in Tank No. This probably was due to the lower pH and perhaps to a lesser degree the lower amount of phosphorus in the effluent.
Because of this, less routine cleaning of weirs and walls in Tank No. Routine maintenance of equipment and structures is necessary to achieve optimum process performance and to avoid major breakdowns. The chemical-biological process which served as the basis for this study offers two significant economic advantages over some of the other schemes which have been proposed for removing phosphorus from domestic wastewater. First, for appli- cation in existing wastewater treatment works, required capital ex- penditures are minimal since no new treatment units normally would be required.
The addition of chemical storage and handling facili- ties are the only plant additions necessary in most instances. In some cases it may be necessary to modify waste sludge pumps and other solids handling facilities in order to accommodate the increased solids production which results from phosphorus removal.
For new facilities construction, no additional treatment units over and above those required for activated sludge secondary treatment would be required. Chemical storage and handling facilities, of course, would be necessary also. Provision for handling the additional solids could often be incorporated into the design for little or no addi- tional cost. These considerations should make the chemical-biological process an attractive alternative when considering the various phos- phorus removal process schemes which are available.
Housing for chemical storage and feeding equipment also would be required in most instances. The type of chemical storage is dependent upon the type of chemical fed liquid or dry and the amount to be fed since this will influence the method of shipment. The cost comparisons presented herein were based on the use of liquid chemical for all three plant sizes shown since liquid systems are generally less costly and wide distribution of liquid alum producing facilities makes its use feasible in many different geographical locations.
The selection of chemical feeding equipment to be used also is depen- dent upon the form and amount of chemical to be fed. Duplicate feeders were assumed to be provided in all instances and all were equipped for automatic pacing from the influent flow meter.
Complete housing of equipment and housing or insulation of storage tanks and feed lines was assumed for the purposes of this analysis. Additional laboratory analyses would also be required for process control but in most instances these would not involve sufficient additional time to warrant additional cost allowances. While this is generally true, it should be pointed out that additional personnel costs can be significant in the smaller plant since the chemical-biological process is relatively more complex than those normally used for secondary treatment.
Additional power costs also would be incurred for chemical feed equip-r ment and handling of the increased solids which result from phosphorus removal. Liquid alum is also cheaper than dry alum where liquid alum is available within a reasonable haul distance. Figure 26 relates chemical cost to the effluent phosphorus concentration based on the results of this study.
The chemical costs used to develop Figure 26 are bulk list prices F. Since freight costs vary so widely, no allow- ance for these costs were included in the overall cost analysis. Table 14 presents cost data for delivery to the State College, Pennsyl- vania area and gives some idea of the effect of transportation costs where the delivery point is considered to be moderate to long distance from the point of production.
This is undoubt- ably higher than would be experienced for many other geographical lo- cations. Alum was the chemical of choice and capital cost estimates included only chemical storage and handling facilities. The basis for amortization was the same as that used by Smith and McMichael 38 in their recent work on costs of tertiary wastewater treatment 4. All costs are expressed in dollars based on the Environmental Protection Agency, average National Index of Brenner 4 has estimated phosphorus removals costs of 4.
Gibraltar betting and gaming association | Society of America, Proceedings, vol, 24, no. Oscillatoria terebriformis C. Mehlhorn, D. However, those dedicated to pollution control pointed out that the objective was to make drinking water not only safe but also palatable. Journal of hcology, vol, 33, p. |
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Lisicki vs radwanska betting expert free | Further, the ecological significance of these endpoints and the actual detrimental effects on the organism are difficult to interpret. Objectives of the Present Investigation The specific objectives of the study were: 1. Cocke ", fig. The supernatant liquid over the sludge blanket was extremely clear with very few sus- pended solids. Much r. The American Chemical Society holds a copyright ownership interest in any copyrightable Supporting Information. Oscillatoria agardhii GomontX after Prescott |
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The higher the rate of self-purification, the more pollutants that can be converted per unit of time. In oligotrophic waters, such a balanced equality essentially exists. Extinction, a de- crease in numbers, or an increase of pollutant-tolerant organisms are the limiting conditions for uncontrolled emission of polluting substances into water bodies.
While the quality of water for drinking purposes gets worse, requests to discharge more pollutants increase. The necessity has arisen to scientifically substantiate the maximum per- missible emission MPE of pollutants into surface waters. It seems to me that the scientific basis should be a balanced equality between the per- missible level of pollution and limits on the amount of discharge. The role of toxic agents in all of the processes of waste assimilation is tremendous because toxicants have a great effect on life processes of pollutant-decomposing organisms.
Even saprophytic bacteria, as is seen in Figure 1, cannot maintain necessary biological activity in the presence of toxic agents and they themselves cannot provide initially the processes of self-purification. One should keep in mind that the nitrifying organisms are more sensitive to many toxicants than are the saprophytic bacteria. Substances in concentrations indicated are not completely harmless for bacteria which mineralize organic substances.
Along with T. Balabanova we carried out tests on the breakdown of or- ganic substances by microorganisms in a medium containing pyror A method of separate determination of BOD, N02 and N03 in closed con- tainers was used in the first series of tests. They were incubated at 25 C. In a second series of tests, open aquarium containers were used with 8 liters of solution the same as in the first series. Air was blown continuously through the aquarium.
The temperature was C. The results obtained are shown in the graphs in Figures 2 and 3. Both in the closed containers Figure 2 and in the open aquaria Fig- ure 3 the processes of decomposition of an organic substance were sup- pressed by the toxic agent--pyror 2-bromonitro-l,3-propanediol ; the degree of suppression was greater the higher the concentration of pyror.
Aminocolophony ch'ioroacetate 2. Pyror 3. Aminocolophony pentachlorophenolate sodium salt 4. Processes of nitrification in solutions of pyror The process of decomposition of organic substances to complete mineralization occurs in the presence of a toxic agent, but to accomplish this requires a great deal of time. The shapes of the curves in Figures 2 and 3 indicates that sapro- phytes and nitrifying agents were hardly suppressed in their activity under the effect of pyror in the first test.
It seems to me that this reflects the following phenomenon. Microorganisms affected by a toxic agent die in a certain quantity. The more resistant specimens remain and, after a certain length of time and a number of generations, clones are produced which are resistant to pyror and which can carry out biological oxidation and nitrification.
But, for the formation of a resistant clone, the greater the concentration of the toxic agent the more time is required. Therefore, according to the balanced equilibrium, the rate of pollutant addition P must not be greater than the rate of decomposition D. In conclusion, one can formulate the following basic positions on per- missible levels of pollution: 1.
Different water uses permit different levels of water pollution. The lowest levels are needed for drinking water supply and fisheries. Organic substances are broken down by different microorganisms in a specific sequence. Toxic substances having an injurious effect on these microorganisms suppress the processes of mineralization more strongly, the higher the concentration. The maximum permissible emission MPE of pollutants into waters must be limited by the permissible level of pollution PLP of a given water at a given time.
MPE, in turn, is limited by processes of self- purification D in which many aquatic organisms, especially microorga- nisms, participate. Their capability and the rate of decomposition of pollutants D must be appropriate to the quality and quantity of pollu- tants discharged.
One cannot make calculations of values for MPE and PLP without tak- ing into account the peculiarities of the water body, the nature of the pollutants and the season of the year. Because the United States has many large streams, large amounts of waste could be placed in them without much apparent effect. As populations in cities and industries grew, however, some streams became open sewers and people in the lower reaches began to complain.
Typhoid fever became common as water supplies deteriorated. By the middle of the last century conditions had become quite bad in several areas. With little or no coordination, surveys and studies were undertaken by people in many areas. Many different approaches were used, and different studies were carried on concurrently, so it is difficult to describe the research as an ongoing program. There- fore the research for detection, evaluation, and abatement of water pollution in the United States will be described briefly under five main headings: 1 Water supply studies; 2 Pollution surveys and studies of natural purification and biological indicators of pollution; 3 Treatment of organic wastes; 4 Development, use, and standarization of bioassay methods; and 5 Determination of water quality requirements for aquatic life and development of water quality standards.
In outlining these activities prime consideration will be given to the most important agencies and organizations. Early developments will be given in detail. Later work will be summarized because in recent years research has attained such diversity and magnitude that even a list of all the projects and their sponsoring organizations would be too long in a review of this type.
Des- criptions of developments since will be largely confined to the activities of the federal agency designated in Public Law and subse- quent federal laws dealing with water pollution. In the Bible lands alum was used for the removal of turbidity as early as B. In the fourth century before Christ Hippocrates advocated the boiling and filtering of polluted water before using it for drinking.
London has been required by parliamentary statute since to filter its water supplies through slow sand filters. The first important modern rapid sand filtration plant was built in at Little Falls, New Jersey. For many years typhoid fever was a disease of prime importance. Through circumstantial evidence it was concluded that typhoid fever was usually associated with contaminated drinking water supplies.
The bacterium responsible for the disease was identified in During the period the incidence of typhoid fever was significantly reduced by better sanitation and filtration of water supplies. After immunization was developed in , the occurrence of the disease decreased rapidly. In the eighteen hundreds the aim was to make domestic water supplies safe. When typhoid fever was conquered, some felt the push for pollution abatement would be weakened. However, those dedicated to pollution control pointed out that the objective was to make drinking water not only safe but also palatable.
Attention was then directed to tastes and odors, turbidity, and color. Whipple, was published in This book dealt with the microscopic life other than bacteria in fresh waters. It was a compilation of limnological data and methods for the study of aquatic organisms.
Although this book was concerned primarily with drinking water, it did enter the field of the natural self-purification of streams, a subject more closely associated with sewage treatment but very significant in water supply. In the preface to the first edition, he mentioned especially W. Sedgwick of the Massachusetts Institute of Technology. He further stated, "To Prof. Sedgwick and Mr.
Rafter water analysts are indebted for the most satis- factory practical method for the microscopical examination of drinking water yet devised. At that time Hassall of London and Ferdinand Conn on the Continent pointed out the correlation between microscopic aquatic life and water purity. The water works departments of the cities in the north- eastern portion of the United States were the first to make studies to detect and identify filter-clogging algal blooms and growths of algae that produce tastes and odors.
To the Massachusetts State Board of Health belongs the credit of having begun as early as a systematic examina- tion of all the water supplies of the state to detect problems in their early stages so effective control methods could be initiated. In the State of Connecticut began a similar study, and city of Boston established at Chestnut Hill Reservoir a laboratory for the systematic study of the biological character of the various sources of their water supply.
Algal control methods and their use developed during the first quarter of this century. Just before the publication of Whipple's book in and in the 28 years between the first and fourth editions of this work, a great deal of effort was devoted to the study of microscopic organisms in water. Clair" in by J. Reighard; an examina- tion of Lake Michigan by Henry B.
Biological stations were established by a number of midwestern universities on or in the vicinity of the Great Lakes and on the shores of smaller lakes in the Great Lakes region. The theological stream studies on the plankton of the Illinois River, begun by Kofoid in and continued through the early years of the present century as a part of the program of the Illinois Natural History Survey, have been an outstanding source of information on the influence of organic enrichment on plankton populations and the effects of these increased growths on water supplies.
The investigations of the U. Public Health Service on the Potomac, Ohio, Illinois, Scioto, and upper Mississippi Rivers have also supplied many valuable data on organic enrich- ment, natural purification, and the growth of algae in streams receiving sewage and other organic wastes. The detection and elimination of pathogenic organisms are essential for the provision of a safe drinking water supply. In their attempts to accomplish this objective, the early bacteriologists found it very diffi- cult to detect and quantify the pathogenic organisms in water supplies.
Because members of the coliform group are constantly present in alimentary discharges, their presence usually indicates fecal pollution and the possible presence of intestinal pathogens. After the further development of culture methods and procedures for enumerating them and measuring the effects of their activity, coliforms became the accepted indicator of fecal pollution.
This test became the criterion and standard method for deter- mining the sanitary quality of a water. Workers in state health depart- ments and water pollution laboratories improved on Smith's test and devised better methods for sampling and culturing coliforms and evaluating and reporting res.
The U. Public Health Service also was prominent in these research efforts. After the passage in of the law authorizing the service to carry out water pollution investigations, a laboratory was established in Cincinnati, Ohio, which was known as the Stream Pollution Investigation Laboratory. In C. Butterfield joined the staff of this laboratory as a bacteriologist. He pioneered in the development and use of coliform tests as indicators of the sanitary quality of domestic water supplies.
These tests were accepted as the tool to be used for the estimation of pollution and its natural purification, the evaluation of sewage treatment, and the sanitary quality of drinking water supplies. Butterfield was also actively engaged in the shellfish sanitation program and in the survey of the performance of representative water-treatment plants in 31 cities along the Ohio River and other rivers of the Midwest and the East.
During the First World War methods were developed for the disinfection of water at army posts and for military operations in the field. An inten- sive and comprehensive study was made to evaluate the bactericidal efficiency of free chlorine and chloramines at different residual levels.
The results of these studies were made available immediately to the army and navy, and the results guided the military in obtaining the most effective and economical use of chlorine for water disinfection. These studies established a scientific basis for municipal water-chlorination practice. The trend of water-supply research from the 's into the early 's is indicated by the title of papers from the Cincinnati laboratory.
At the end of the Second World War, membrane filter techniques were developed, compared with earlier procedures, and standardized. In this period studies were made to develop methods for distinguishing human coli- forms from those of other animals. In the early fifties viruses in water supplies were studied at the Robert A.
Taft Sanitary Engineering Center in Cincinnati. These studies were directed toward the detection, enumeration, and production of viruses in the laboratory, the determination of their effects, and their control or removal by sewage treatment. A large number of papers appeared in the 's describing the results of this research on viruses in water supplies. Studies of the toxicity of heavy metals in domestic water supplies have been in progress for a number of years in several laboratories.
This activity was expanded because of the increase in metals and the need for more definite data for the setting of drinking water standards. Extensive studies have been and are being carried on to develop methods for collecting these materials from water supplies and other portions of man's environment and to determine their possible carcinogenic and other adverse effects. Following the passage by the U. Congress in of Public Law , which was an important milestone in the struggle to abate pollution, the Cincinnati laboratory of the U.
Activities were reor- ganized, and more emphasis was placed on research by the establishment of a Research and Development Branch. An Aquatic Biology Section was set up under my direction. The research effort was divided between two projects: the biology of water supply and the determination of water quality criteria for aquatic life.
The water-supply unit, under the leadership of C. Palmer, directed its studies to the identification and control of organisms producing tastes and odors, to the identification and removal of substances producing tastes and odors, and to the identification of filter-clogging organisms and their control.
The usual method for the control of tastes and odors in water supplies was to treat with chlorine or absorb the offending sub- stances on activated carbon. The chlorine treatment was entirely experi- mental and often was ineffective or resulted in the production of even more odoriferous materials. The activated carbon treatment was usually success- ful, but it often required tremendous amounts of carbon, which were costly and presented a disposal problem.
Something more exact than the cure-all chlorine treatment was needed. The first step in meeting the problem was to grow pure cultures of those algae suspected of producing taste- and odor-causing substances to determine which species actually produced such substances. The next step was to collect and isolate those materials and determine their chemical composition.
It was believed that, if the chemical compositions of these materials were known, methods could be developed for their removal from or destruction in water-treatment plants. Over species of algae were grown in pure culture, but this line of research was not further supported, and equipment and staff necessary for making the chemical analyses were not secured. Cultures were grown and odoriferous materials were isolated, but research for their identification was not accomplished. This enrichment plus detergent carriers, certain industrial wastes, and runoff from heavily fertilized agricultural lands has produced large algal populations and the eutrophication of many lakes and reser- voirs.
These growths cause serious problems for water-treatment-plant operators because of the clogging of filters. In some localities at certain times backwashing requires one-fourth of the time of operation. This procedure greatly increases costs and reduces the volume of finished water produced. Known and suspected filter-clogging algae were cultured for screening tests in an effort to determine the species causing the trouble and to find a better and more selective algicide than copper sulphate.
Series of screening tests were made with new materials that were rapidly appearing on the market in the 's. We wanted to find algicides that were specific for the target species and nontoxic to the others. Al- though several good algicides were found, specific materials were not found before the research work was discontinued when biological research was transferred to the new national water quality laboratories.
In conjunction with the algicidal studies, research was carried out for the development of biological controls. We found that several algae pro- duced materials that inhibited the growth of other algae. We also found that several algae produced antibiotics. In the course of these studies a virus that destroys some bluegreen algae was discovered. Studies of this virus have continued at the Cincinnati laboratory. Commission of Fish and Fisheries in the early 's indicated a national awakening of interest in our fisheries and their protection.
It had been noted that fishing was greatly reduced or eliminated in many streams receiving sewage or industrial wastes, or both. Fishermen began to complain and to point out the need for pollution abatement. As a result of these complaints, studies to determine the effects of pollution were undertaken. In the 's Stephen A. Forbes of the Illinois State Laboratory of Natural History began investigations of the Illinois River, which later established a firm base for the comparison of stream conditions before and after pollution.
The study of the Illinois River by the Illinois Natural History Survey is a classical study of the effects of stream pollution, natural purification, and biological indicators of pollution. As sewage from the city of Chicago was added to the river through the Chicago Drainage Canal, the pollution moved progressively down the river as the city and the waste load grew.
This provided an excellent opportunity to observe and study the progressive chemical, physical, and biological effects of increasing pollution. The findings of these exceptionally pertinent investigations have been presented in a large number of publications appearing over a period of half a century. They describe changes in the aquatic biota as the pollution moved downstream and also the natural purification brought about by the aquatic biota found in the different areas.
These studies dealt in detail with the plankton, bottom organisms, and fishes, and changes in their populations over the years as the organic load increased and the zones of pollution moved pro- gressively downstream. After the turn of the century, many pollution surveys were made by state conservation or fish and game departments and state health depart- ments.
After the passage of the federal law of , the U. Public Health Service made a survey of the Potomac River in At the urging of W. Sedgwick of the Massachusetts Institute of Technology, W. Purdy entered the pollution field and served as the plankton expert for the survey. He studied the biology of the river and its flats and pointed out the great value of the tidal flats for the digestion and natural purifica- tion of the organic wastes from the city of Washington, D.
His findings were presented in a paper entitled "Investigation of the Pollution and Sanitary Condition of the Potomac Watershed. There he worked with the bacteriologist, C. Butterfield, and later with the chemist, C. Ruchhoft, who joined the laboratory staff in These three men and their small staff made many valuable advances in the field of water pollution research and pollution abatement.
They participated in the Ohio River surveys of and , the Illinois and Scioto River surveys, and the Lake Michigan survey. The results of their studies were reported in a series of papers under two main headings, "Experimental Studies of Natural Purification in Polluted Waters" and "Studies of Sewage Purification. It was built on the laboratory grounds on a slope to ensure the desired current.
Water and a sewage waste were fed in at the upper end. This artificial stream was observed year round, and it supplied valuable data on natural purification; the role of different organisms in the purification process; seasonal changes in the pollution zones and the purification process; and the populations characteristic of the different pollutional zones. During the period from until the Second World War, pollution sur- veys were made of many streams throughout the country by state and federal agencies.
Several universities conducted related biological studies or co- operated with the state surveys. Birge and Juday of the University of Wisconsin made limnological studies in the lakes of the state. The New York Stream Survey under the direction of Emaline Moore supplied valuable data on aquatic populations living in organically enriched streams and lakes.
This survey was planned and carried out so that one or more river basins were surveyed each year. Special attention was given to polluted waters, the cause of pollution, and its effect. As data on the extent of pollution and its effects became know, an ever-increasing demand developed from fishermen, sportsmen's clubs, civic groups, and fish and game departments for strong federal laws to control pollution.
Early in the 's the Isaac Walton League initiated a national program for pollution abatement. This campaign was more effective than the former attempts. The passage in of Public Law was due in part to the efforts of this group. Bureau of Fisheries and its successor, the U. Fish and Wildlife Service, conducted surveys in several areas. In a biological survey of the upper Mississippi River with special reference to pollution was carried out under the direction of A. Several very productive surveys were made by M.
He approached the problem from the viewpoint of a physiologist and made many important contributions on the environmental requirements of aquatic organisms. Ruth Patrick of the Philadelphia Academy of Natural Sciences made exten- sive studies of the role of plankton, especially diatoms, as indicators of stream health or pollution. In connection with these studies the "diatometer" was developed for the sampling of certain elements of the plankton population.
The stream was sur- veyed, and a map was prepared showing pools, riffles and runs, and different bottom types, as well as stream widths and depths. A sampling program was established, and sampling stations were selected. A broad crested weir and gauging station were built, and a weather station was established. A trailer laboratory was equipped and placed near the Wilmington, Ohio, primary sewage treatment plant and was used as a field headquarters for chemical analyses and biological studies.
Periodic sampling studies over hr periods with samples taken at each sampling station every hour were conducted over a 2-year period. At least one such continuous sampling was carried out in each of the seasons for each year. During these studies hourly samples were taken for the determination of 02, C02, pH, temperature, acidity, alkalinity, and turbidity.
Hourly plankton samples were taken during the hr sampling periods to determine seasonal and die! Periodic samples of the benthic macro- and microinvertebrates were taken throughout the year under the direction of A. Monthly seinings for fish were made at all stations throughout the stream. These studies and samplings provided data on the various pollutional zones: their biological, physical, and chemical characteristics; and sea- sonal and die!
This extensive and intensive study produced many valuable data and several new concepts. It was concluded that the quantitative and qualitative makeup of the biota was characteristic of the so-called zones of pollution and was indicative of environmental conditions or pollution. The mere presence or absence of any single species could not be considered as an indicator of pollution. In a polluted stream 02, C02, and pH could vary widely over a hr period at the same station.
Such variations were especially noticeable in the upper recovery zone where there were large growths of algae. These data indicated that the sag curve, developed by nonbiologists who ignored the effects of algal growths, could be very misleading, especially in the smaller streams, because the samples for its determination were usually taken after noon.
Other important findings were the seasonal shift in zones of pollution and changes in their character, the extension of Sphaerotilus growth downstream in winter, the failure of fishes to enter in winter the septic zone of summer even though 02 was abundant and the inapplicability of the K factor developed for large rivers like the Ohio River to small streams such as Lytle Creek, where it was 1.
Data resulting from the Lytle Creek studies were reported in some 15 publications. At the termination of the Lytle Creek studies in , the laboratory bioassay studies of the Biology Section were increased. Dimick and C. Warren for Oregon State University. Biological studies at the State of Ohio Fish Hatchery at Newtown were expanded over the years, and a temporary field laboratory was constructed in the late 's.
Dilution water for toxicity bioassays was secured from the hatchery spring, and some of the hatchery ponds were used for field studies. Bioassay studies and the facilities at the Newtown field station were expanded under the immediate direction of Donald Mount, who joined the staff of the Biology Section in Eventually, the building was enlarged and the hatchery was secured for the toxicity bioassay studies.
Investigations for the improvement of sewage treatment were carried out by state health depart- ments and other state agencies. Rutgers University was one of the leaders in this endeavor. Valuable work was conducted by William Rudolphs and H. Shortly after the establishment of the U. Public Health Service Stream Pollution Investigation Laboratory in Cincinnati, a series of investigations was undertaken that has continued to the present time under different names.
The results of basic studies conducted during the 's, 's and 's were published under the general title "Studies of Sewage Purification," by Butterfield, Purdy, and Ruchhoft and their small staff. Butterfield, in cooperation with Purdy, demonstrated the role of certain protozoa in keeping bacterial populations active and efficient in the utilization and breakdown of organic materials.
Butterfield investigated the die-away of coliforms in polluted waters and pioneered in isolating zoogleal bacteria from activated sludges. He also demonstrated that activated sludges consisting of pure cultures of zoogleal bacteria were capable of rapid and efficient removal of BOD from both synthetic and natural sewage. Purdy published papers on the bulking of activated sludges as observed at the Tenafly, New Jersey, sewage treatment plant and the use of chlorine for the correction of sludge bulking in the activated sludge process.
James Lackey, who worked at the Cincinnati Laboratory from the 's to the 's, published a series of papers under the general heading "Biology of Sewage Disposal. Chemical studies of the sewage-treatment and natural purification pro- cesses were conducted by Ruchhoft and his staff. They developed analytical methods for the detection and determination of waste materials and for tracing waste streams to their sources in connection with stream surveys.
Considerable time was devoted to the development and improvement of the BOD and COD tests and stream-survey methods and tests. Carcinogenic substances were found to be pre- sent in small quantities in some water supplies. The carbon-filter techni- que for the removal and concentration of trace materials from water used for domestic supplies has in recent years brought to light the presence of undesirable substances in water supplies hundreds of miles from their point of discharge.
It has also resulted in more emphasis on the detection and control of toxic and harmful materials in drinking water supplies. With the development of better analytical equipment and techniques, many problems are being detected and solved that 30 years ago were impossible to solve because of the lack of equipment and methods to detect and analyze materials occurring in very small quantities in our waters. In McDonald reported on his studies of the toxic effects upon young shad of wastes from the Page ammoniacal works.
In Knight reported on his bioassay studies, and Moore and Kellermann reported results of their bioassays in and In Marsh reported on studies of the toxicity of some industrial wastes to fish. In the same year Levy reported to the State Water Committee of Virginia on the investigation of the effects of trade wastes sulphite waste liquor on the waters of the James River at Richmond. In Marsh reported on the lethal dose of copper sulphate in waters of different quality.
Clark and Adams reported results of their bioassay studies in Massachusetts in Wells conducted extensive bioassys, and in he reported on reactions and resistance of fishes to different concentrations of C02 and 02 and in on reactions and resistance of fishes to salts in their natural environment.
The use of bioassays increased between and In Adrian Thomas conducted bioassays to test the toxicity of road tar. He used one trout fingerling in each ml container and exposed the test fish to two concentrations, 66 and 13 ppm by volume, for days. Water in the test chambers was changed once a week or more often. Aeration was very heavy, and it may have removed some of the volatile components.
In Shelford and Wells reported on the use of sunfish to determine the toxicity of gas house wastes. These were short-term acute toxicity bioassays of only 1-hr duration. An important observation was that fish do not avoid this waste, but swim into it. In Shelford reported on his continuing studies of the effects of gas house wastes on fish. In Powers described his bioassay studies in which he used the goldfish Carassius carassius as the test animal. He reported additional work in on the influence of temperature and concentration on the toxicity of salts to fishes.
In Thomas of the Department of Game and Inland Fisheries of Virginia presented a paper before the American Fisheries Society on the effects of certain oils, tars, and creosotes on brook trout. The work of David Belding is noteworthy, as he had a good understanding of the factors influencing the results of bioassays and the toxicity of wastes and materials to aquatic life. In the paper by Belding, Merrill, and Kilson, "Fisheries Investigations in Massachusetts," differences in the sensitivity of different species to the same toxicant are pointed out.
They found that brook trout were seven times more sensitive than carp and 28 times more sensitive than goldfish to H2S. The authors stated, "There is a marked difference in closely allied species such as the Salmonids. They also pointed out that fish vary seasonally in their resistance to toxicants; that the quality of the receiving water affects toxicity; and that size or weight of fish per volume of test solution, flow of water, 02 concentration, and temperature are very important factors that influence results.
Although he used only hr tests, he recognized that longer exposures at lower concentrations would produce kills. In his bioassays he tested the toxicity of 20 materials to brook and rainbow trout, Chinook salmon, carp, goldfish, and suckers. Reports are available from several other investigators who carried out bioassays in the 's.
In Nightingale and Loosanoff used early life stages of the Chinook salmon to test the toxicity of waste sulphite liquor. Cole, Dilling, and Healey also conducted bioassays during this period. In Thomas published a paper on the absorption of metal salts by fishes. Wiebe conducted toxicity and pollution studies for a number of years and reported on exposure of young fish to varying concentrations of arsenic in and to sudden changes in pH in ; he also reported on effects of dissolved phosphorus and organic nitrogen in the waters of the Mississippi River in During the 's bioassays were increasingly used for the evaluation of problems by state and federal investigators.
Studies were made of the toxicity of cyanides, phenols, gas house wastes, pulp and paper mill wastes, oil and petroleum products, and metals. Extensive studies were also made on 02, C02, temperature, and pH requirements. Many bioassay in- vestigations were carried out by the states and the U. Bureau of Fisheries, which later in the decade became the U. Fish and Wildlife Ser- vice. Among the latter, the research of Ellis was outstanding. In Surber and Meehan reported on lethal concentrations of arsenic for certain aquatic organisms.
Galtsoff made valuable contributions to knowledge of the effects of oil on marine organisms, especially its effects on shellfish. During the 's bioassays were performed at some universities. Among these the work of Anderson with Daphnia warrants special mention. Of work carried out in state laboratories that of Burdick in New York is outstanding.
With the introduction of the synthetic organic pesticides in the 's, there was a nation-wide surge of investigations of the toxicity of these materials to aquatic life. Public Health Service and the U. Fish and Wildlife Service took dominant roles in these studies.
Public Health Service at Savannah, Georgia, I carried out and directed extensive studies of the effects of ground and airplane spraying of DDT for mosquito control on aquatic life. Effects of weekly applications of DDT and other insecticides to water areas at 0. Plankton, surface and benthic invertebrates, terrestrial insects especially bees , fishes, amphibians, reptiles, birds, and mammals were studied.
Applications of the insecticides were made by hand dusters and sprayers and by airplane dusts, sprays, and thermal aerosals. Results of this 3-year study were summarized in a series of papers in the Public Health Reports of the U. Public Health Service. As the number of investigators performing bioassays increased, many different procedures, test organisms, dilution waters, and materials were used.
This diversity resulted in great difficulty in the comparison and evaluation of the results reported by different investigators. Some uniformity in testing procedures and in the reporting of results was needed.
In Doudoroff, who was then on the staff of the Biology Section of the Environmental Health Center at Cincinnati, invited prominent workers in bioassay investigations to join him as members of a committee to study the various bioassay procedures being used and to select or devise and recommend procedures for bioassays which they considered best for short-term toxicity tests with fishes.
Members of this committee were: P. Doudoroff, Chairman; B. Anderson; G. Burdick; P. Galtsoff; W. Hart; R. Patrick; E. Strong; E. Surber; and W. Van Horn. The committee met several times in Cincinnati and once in Woods Hole to draw up their recommendations.
Doudoroff and his associate, Max Katz, published a succession of papers on bioassay studies and pertinent literature reviews while with the Biology Section during the 's and early 's. Taft Sanitary Engineering Center. During this period the U. Fish and Wildlife Service established a special pesticide bioassay laboratory at Columbia, Missouri, the purpose of which was to evaluate the toxicity of the new synthetic organic pesticides to aquatic life. Another laboratory was set up at La Crosse, Wisconsin, for the purpose of discovering materials or chemicals that were specific for the control of undesirable aquatic species and that would act without harm to desired organisms.
This laboratory has a field station at Warm Springs, Georgia. After the growth in the use of bioassays was so rapid and so many new workers entered the field in both the freshwater and marine environ- ments that it is impossible to deal with all the developments and findings in a review of limited size. It is proposed, therefore, to limit the coverage of research activities after to those developments that in my opinion have been most important in leading to the present pollution abatement program of the U.
It appeared to me that, while some improvements had been made, overall the situation was worsening. Several approaches had been tried, but apparently a different approach was needed. Pollution abatement cases in court were drawn-out and were often lost in long arguments over what concentrations of wastes were really harmful and what really constituted pollution.
Local people and the courts were influenced by threats of industry to move to another state. Some companies hired consultants to run short-term bioassays to indicate that the concentrations of their waste in the receiving water was not lethal.
Hardship cases were pleaded on the grounds that industries that were forced to treat their wastes, while industries in other states were not, would be at an economic disadvantage. Further, although chemical analyses had been made and the materials in wastes identified, no firm data were available to indicate the maximum concentration of waste that was not harmful under long-term or continuous exposure.
Courts were often not in sympathy with what they considered drastic action in view of the supporting data, and they and many people locally affected concluded that the only choice was fish or jobs, as suggested by industrial and chambers-of-commerce spokesmen. In such a situation they decided to take the jobs and let the environment take care of itself. Suggestions had been made that government should tell industries how to treat their wastes.
Lack of such information was used by some industries as an excuse for inaction, as no one had told them how to treat their wastes at a profit. I reached this conclusion because: 1 Such standards would be uniform over large areas, everyone would be required to meet them, and no economic advantage could be acquired by anyone through exemption from treat- ment; 2 requirements would apply to all sections of the country, and thus there would be no incentive to move to escape them; 3 standards would be based on carefully determined require- ments, and no one would be required to treat more than the essential amount; and 4 the standard, based on scientifically determined require- ments, would provide a firm base for legal actions to abate pollution.
Since standards should be based on water quality requirements, the first task in a pollution abatement program is to determine water quality requirements. Because a water that is favorable for aquatic life is suitable for all other uses with recourse to available treatment methods, with the possible exception of NOs in drinking water and bathing waters, discussions of research in this review have been confined to those dealing with the requirements for aquatic life and water supply.
Essential research that is to be considered is, therefore, that which is directed toward the determination of water quality requirements for aquatic life. Because the determination of water quality requirements for aquatic life is largely a research problem in environmental requirements, ecology, and toxicity, a well-trained, effective, and motivated scientific staff is required along with money for the program, facilities, and equipment essential for the research.
Because many of the biologists working in the U. Public Health Service regions felt isolated, a conference for all aquatic biologists in the Service associated with any phase of water pollu- tion research and investigations was held in Washington, D. This conference raised morale, fostered cooperation, promoted the exchange of ideas and data, and improved the research effort. Steps were taken to acquaint the leading conservation organizations with the use and value of water quality standards in a pollution abatement program.
Contacts with these groups were continued through the 's. I discussed the need and value of water quality standards in six papers published between and A new section on the biology of water supply and water pollution was included in the review of the literature of A larger section was submitted for inclusion in the review.
This dealt with bioassays, studies of the toxicity of chemicals and wastes to aquatic life, and biological indicators of pollu- tion. The coverage was greatly expanded in the following years, and every effort was made to supply summaries of papers dealing with environmental requirements, the toxicity of wastes and other materials to aquatic life, and water quality criteria and standards. To promote further the objectives of the meeting held in Washington, D.
This meeting was attended by representatives from industrial concerns, academic institu- tions, state conservation and health departments, and federal agencies. Twenty-eight states and four provinces of Canada were represented.
Biolog- ical indicators of pollution, water quality criteria, and the use and value of bioassays were discussed. Proposed standard bioassay methods, prepared by a committee under my chairmanship and based largely on the report of the Doudoroff committee, were included in the llth edition of this work which was published in Their inclusion was instrumental in promoting more uniform procedures, better and more comparable data, and greater use of bioassays as a research and monitoring tool for the abatement of pollution.
From through research for the determination of water quality requirements for aquatic life, the improvement of bioassay methods, and the determination of the toxicity of pesticides was promoted to the fullest extent possible by the Biology Section of the Cincinnati laboratory. The research findings of the section during this period were described in publications.
Attendance was much larger at this meeting than at the first seminar. The seminar theme was the effects of pesticides on aquatic life and allowable concentrations of various pesticides in the aquatic environment. Other subjects discussed were the effects of the dis- charge of radioactive materials, environmental requirements of aquatic life, marine and estuarine problems, and the practical application of biological findings in pollution abatement.
Contact was maintained with the private national conservation agencies, and the leaders or staff members of a number of them attended the second seminar. An advisory committee on water quality standards for aquatic life made up of the leaders of these groups was established in Cottam, director of the Welder Wildlife Foundation formerly director and assistant director of the U. Callison, executive vice president of the Audubon Society. These conservation organizations presented testimony before congres- sional committees on various issues at frequent intervals.
Some of their testimony, especially that of Richard Stroud of the Sport Fishing Institute, presented the need for and the value of national water quality laboratories, one for fresh waters and one for marine waters, to carry out research to determine water quality requirements for aquatic life. In April the House of Representatives passed legislation authorizing two water quality laboratories and appropriating money for their construction.
The Senate passed a similar bill in June. The conference committees came to an agreement in August, and the bill authorizing the laboratories was signed into law on August 12, The theme of this meeting was water quality requirements for aquatic life. Every possible effort was made to secure leading investigators to present papers and to assemble the best possible program dealing with the chosen theme.
The objective was to produce a handbook summarizing available data on water quality requirements for aquatic life. Representatives of 26 nations were in attendance. Leaders of the national conservation groups took a prominent part in the seminar, which was held August , , just after the passage of the legislation providing for the construction of the two water quality laboratories.
Planning for the water quality laboratories was largely completed in June Planning for the research program had been under way even before the laboratories were authorized. The following year several thousand square feet of space was made available by the University of Minnesota at Duluth.
The staff was enlarged and research activities began. A search was made for laboratory space on the coast, which could be used for research activities before the construction of the new laboratory. Since none was available, the labora- tory was set up in a former industrial laboratory at West Kingston, about 8 miles from Narragansett Bay.
The assembled staff moved into this building in September Laboratory furniture, equipment, and supplies, and a laboratory staff were secured and assembled for both of the water quality laboratories, and the research program for the determination of water quality requirements for aquatic life was initiated under my direction.
Construction of the National Marine Water Quality Laboratory at Narragansett, Rhode Island, was delayed, but construction of the National Water Quality Laboratory at Duluth proceeded, and it was completed in the summer of and dedicated on August 12, Construction of the National Marine Water Quality Laboratory was not initiated until August 12, , 13 years after authorization.
In case a state did not do this and failed to call a pbulic hearing, the Secretary of the Interior was authorized to set water quality standards for the interstate waters of that state. On February 27, , the Secretary appointed an advisory committee to recommend water quality criteria for the following uses: Aesthetics and recreation; public water supply; fish, other aquatic life, and wildlife; and agricultural and industrial water supplies.
The committee on fish, other aquatic life, and wildlife was composed of 28 members of varied training and experience who collectively covered all phases of the subject and represented a great deal of experience in bioassay studies and water quality requirements for aquatic life. Their task was to review available data on the water quality requirements of aquatic life and then, on the basis of available data, their experience, and judgement, to recommend water quality criteria.
Their report was completed by mid-June Their report on research needs was completed in the spring of , and both reports were published in April along with the reports of the other committees. This report was updated and expanded by a large committee of the National Academy of Sciences and the National Academy of Engineering and was published in under the title "Water Quality Criteria Methods had been suggested for the use of application factors with data from acute toxicity studies to predict long-term effects of toxicants, but few data were available to indicate the maximum concentration of a toxicant in the aquatic environment that was not harmful with continuous exposure.
Studies of physical environ- mental requirements, especially temperature and 02, has received the most attention, and several field studies that extended over longer periods had been made. Oxygen and temperature requirements of fishes were investigated by a number of workers in the 's and 's.
However, most of the investigators reported on temperature and oxygen levels that were lethal, and very few dealt with conditions that were favorable for the survival of the species or that enabled them to compete successfully with their competitors and predators. In the late 's Bel ding gave a good analysis of the problem. The best work on environmental require- ments in this period was that of M. Ellis and his staff.
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The specific surface area determined using the classical N2 BET method after freeze drying the material was ± 30 m2 g−1. of mm were used, but at “P”, a wider column of a pool filter type with a diameter of mm was used. Gfw Wasser Abwasser 06/ (), pp. J. Colloid Interface Sci., (), pp. The selected materials representing very different types of adsorptive According to the ranking of BET-surface areas and additionally seen by the Karcher, S.: Eignung verschiedener Sorbentien zur Entfernung von Reaktivfarbstoen aus Abwasser. 36(2), (). doi/ schweig, Germany; American Type Culture Collection, Rock- ville, Md. were used: (i) ALF, BET, and GAM, complementary to clarifier x. -,. APPL. ENVIRON. Phosphorelimination aus Abwasser. gwf-Wasser/Abwasser for biological phosphorus removal. FEMS Microb. Ecol. Tjernberg.