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Volatile organic components of municipal primary sewage effluent after chlorination and dechlorinationMori, Brian Tomio January 1976 (has links)
The extraction, separation and identification of volatile organic components
of primary effluent before and after chlorination was undertaken to ascertain whether the chlorination of treatment plant effluents results in the formation of new volatile chlorinated organics.
Extraction efficiencies of 70 to 90 percent of an aqueous solution of phenols were obtained by both continuous solvent extraction and sorption on a column of a macroreticular resin. Tests with primary effluent showed that the macroreticular resin recovered a slightly larger number of compounds than the solvent extractor which also suffered from emulsion problems.' Since the resin was also expedient in handling replicate samples it was adopted and further studies indicated that it had a capacity of 1.7 mg TOC/cc of resin and recoveries
of the phenols were unaffected by pH or detergents.
Preliminary separation of the. .components on the basis of acidity with .05'M^NaOH and diethyl ether and by thin layer chromatography on silica gel with pet ether and methanol proved to be useful. Gas chromatographic (GC) studies with various silicone liquid phases demonstrated that OV-101, 0V-17, and 0V-225 all provide good separation after optimization of temperature programs.
Primary effluent samples taken from Lion's Gate Treatment Plant in North
Vancouver on Monday mornings proved to be remarkably consistent in their GC
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traces as monitored by Ni electron capture (EG) and flame ionization (FID) detectors. A series of spectacular new peaks was consistently observed by EC as a result of chlorination, but the FID showed only minor changes. Dosage levels of up to 120 mg/1 Cl₂ (NaOCl) produced similar chromatograms while a dosage of 200 mg/1 produced a new set of changes not found at the dosage levels used in treatment plants. Gas chromatographic studies with a micro- electrolytic conductivity detector showed that 10 or 11 new halogenated peaks in the neutral and basic fraction and 6 or 7 new halogenated peaks in the acidic fraction result from chlorination. These compounds all of which are in μg/l concentrations account for only 0.01 percent of the applied chlorine dosage but make up about 40 percent of the more volatile organically bound halogen present in chlorinated primary effluent.
After a series of partially successful attempts by retention time, GC-MS and GC effluent trapping, a number of components were positively identified by a computerized GC-MS. TRirty-one compounds were positively identified by mass spectra and GC retention times, another 24 were tentatively identified by mass spectra and an additional seven were very tentatively identified by GC retention
times. Only three of the compounds resulting from chlorination were positively identified. All compounds identified by mass spectra are present in
concentrations in primary effluent. The implications of this study and suggestions for further investigations are also discussed. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate
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The selective dechlorination of poly-chlorophenolsThomas, Maxwell Paul January 2009 (has links)
Liquid phase catalytic hydrodechlorinations can provide a convenient and environmentally friendly method for treating organic chlorinated compounds in waste streams generated during the manufacturing of agrochemicals. During such treatment hydrochloric acid is generated as a by-product, which can be easily neutralized employing a base to yield an inorganic salt. This work describes the results obtained during the liquid phase hydrodechlorination of 2,6-dichlorophenol (2,6-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP). The hydrodechlorination of these chlorinated phenolic compounds in a mixture of methanol and water was investigated using supported and unsupported palladium catalysts to yield lower chlorinated phenols or phenol. Various parameters were investigated such as catalyst concentration, ammonium formate concentration, effect of base addition and effect of temperature. During this study two methods of hydrodechlorination were also investigated such as hydride-transfer hydrogenolysis, using ammonium formate, and hydrogenolysis, using dihydrogen. These methods offer a mild treatment in terms of the reaction temperature with temperatures used below 800C. A comparison of the palladium catalyst systems using these methods also showed that Pd/C produced the best results in terms of the hydrodechlorination rate and the selectivity towards phenol. When the ammonium formate method was used, complete hydrodechlorination of both substrates was achieved in 1h of reaction time at a selectivity of 100 percent towards phenol. A comparison of the method using dihydrogen and Pd/C showed that the reaction rate and the selectivity towards phenol during the hydrodechlorination of 2,6-DCP were 87.92 percent and 93.30 percent. Similarly, the reaction rate and selectivity during 2,4,6- TCP hydrodechlorination were 63.77 percent and 70.57 percent. These results were achieved in a reaction time of 3 hours. A high catalyst loading increases the reaction rate at the expense of selectivity, due to the formation of cyclohexanone, formed during further hydrogenation of phenol. The formation of cyclohexanone was limited at high temperatures (ca. 800C) with none detected during the hydrodechlorination of 2,6-DCP and 0.19 percent during the hydrodechlorination of 2,4,6-TCP. Evaluation of the hydrodechlorination parameters showed that the catalytic efficiency of the Pd/C catalysts was inhibited as the reaction proceeded due to the formation of HCl as by-product. A significant increase in the reaction rate was achieved when the reaction was performed in the presence of an inorganic base, which neutralized HCl.
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Regrowth of E. coli and S. faecalis in treated sewage after chlorination in a continuous-flow reactorSaunders, Kathleen G. 12 June 2010 (has links)
The objective of this study was to examine the regrowth of E. coli and &. faecalis in chlorinated, secondary-treated sewage effluent using a continuous flow system. Regrowth was evaluated at varying chlorine contact times and chlorine residuals. In addition, chemical and physical characteristics of the sewage were evaluated in relation to regrowth.
The results showed that while a 99% kill of E. coli could be achieved, regrowth always occurred regardless of the chlorine residual and contact time. S. faecalis never regrew in the chlorinated sewage. No single parameter could be identified as the most important in controlling the extent of regrowth. / Master of Science
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The effect of continuous mechanical mixing on the iodine disinfection of settled domestic sewageClingenpeel, William Hoskins January 1966 (has links)
The object of this was to investigation the effect of continuous mechanical mixing on the disinfection of settled domestic of settled domestic sewage with iodine. The variable investigated was the power input to the system which was a function of mixing intensity.
Five experiments were run usfrtt a six-bladed turbine agitator in a fully baffled tank. The mixing intestines of the first three experiments were 0.292, 0.00748, and 0.0641 foot pounds per second per 1,000 gallons, respectively. The mixing was contInuous throughout the experiment. The last two experiments employed a mixing intensity of 0.000876 foot pounds per second per 1,000 gallons. Most Probably Number determinations of Escherichia coli were made at time intervals of 0, 0.5, 1.5, 2, 3, 4, 6, 8, and 10 minutes respectively, for each experiment. All ten minute Iodine residuals were in the range of 1.70 to 1.80 parts per million. Alt experiments were conducted at 20 degrees centigrade.
Similar rates of disinfection were obtained at mixing intestines of 0.292, 0.0641, and 0.00748 foot pounds per second per 1,000 gallons. The disinfection rate at 0.000876 foot pounds per 1,000 gallons was inferior to that of the previously mentioned rates.
The following conclusions were made after comparing these results with a previous investigation.
1. Similar continuous mixing disinfection occurred in the range of power to volume ratio of 0.00748 to 148 foot pounds per second per 1,000 gallons.
2. Inferior continuous mixing disinfection·occurred at the power to volume ratio of 0.000876 foot pound per second per 1,000 gallons and under the condition of no mixing.
3. A system operating at the power to volume ratio of 0.00748 foot pounds per second per 1,000 gallons for one minute·appears to provide for complete blending of iodine with the sewage under the conditions of the present Investigation. The suggested power requirement is equivalent to 9.46 x 10⁻⁶ horsepower per million gallons per day. / Master of Science
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An investigation of the methods used in the determination of the chlorine demand of settled sewageWilliams, Charles Edward 06 February 2013 (has links)
The chlorine demand correlations, which exist in the settled domestic sewage at the V.P.I. Sewage Treatment Plant between the limits of one and seven ppm, of applied chlorine dosage were determined. / Master of Science
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The Chlorination of Amino Acid in Municipal Waste EffluentsBurleson, Jimmie L. 07 1900 (has links)
In model reaction systems to test amino acids in chlorinated waste effluents, several amino acids were chlorinated at high chlorine doses. (2000-4000 mg/1). Amino acids present in municipal waste effluents before and after chlorination were concentrated and purified using cation exchange and Chelex resins. After concentration and cleanup of the samples, the amino acids were derivatized by esterification of the acid functional groups and acylation of the amine groups. Identification and quantification of the amino acids and chlorination products was carried out by gas chromatography/mass spectrometry, using a digital computer data system. Analysis of the waste products revealed the presence of new carbon-chlorine bonded derivatives of the amino acid tyrosine when the effluents were treated with heavy doses of chlorine.
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The effects of rhodamine WT and chlorine on the recovery of fecal coliformsVinson, Kenneth E. January 1982 (has links)
Fecal coliforms suspended in a natural stream water were exposed to rhodamine WT dye, chlorine and both in combination. Samples were analyzed for coliforms by three enumeration techniques.
Statistical analyses of data by the paired-t test showed that for non-chlorinated samples no significant difference (0.10 level) was found between the recoveries by the three enumeration techniques. For chlorinated samples the standard membrane filter technique (Std-MF) yielded significantly lower recoveries (0.05 level) than the standard MPN procedure. A modified membrane filter technique employing a two-layer agar and a five hour 35°C preincubation period (Mod-MF) was found to yield recoveries consistently greater (0.05 level) than the standard MF technique.
The data showed that exposing fecal coliforms to 100 to 1,000 ppb of rhodamine WT dye for 30 minutes, did not inhibit the recovery or enumeration of the organisms by any of the three assay methods.
The number of fecal coliforms that survived exposure to 0.2 to 0.3 ppm of chlorine and 10 to 100 ppb of dye was not significantly different from the number enduring contact with similar concentrations of chlorine alone. / Master of Science
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Removal of microorganisms and proteins from sewage and industrial waste with chlorinated solventsDawson, Herbert Maxwell 07 April 2010 (has links)
Very few sewage and industrial waste treatment effluents are free from microorganisms and proteins. Such discharges require further treatment by the receiving stream and consequently lower stream quality. The object of this investigation was to evaluate chlorinated solvent processes for the removal of microorganisms, proteins, and other substances from sewage and other wastes.
Six different chlorinated solvents were added to different waste samples in the ratio (by volume) of five percent solvent and 95 percent waste, mixed and allowed to settle for a specified period of time. The efficiency of the solvent extraction process was evaluated in terms of reduction of suspended solids, biochemical oxygen demand, and by increased weight of residue separable by sedimentation. The results showed that the process produced the following effects on settled sewage. Suspended solids were reduced by 85 percent, the weight of residue separable by sedimentation was increased 33 percent, and the biochemical oxygen demand was reduced 49 percent.
The process was less effective for the treatment of raw sewage, trickling filter effluent, sewage lagoon effluent, or for separation of activated sludge.
The variables investigated were temperature, pH and the solvent waste system. Temperature and pH appeared to have negligible effects on the extraction efficiency. The solvents employed were; chloroform, ethylene dichloride, chlorobenzene, carbon tetrachloride, trichloroethane, and dichloroisopropyl ether. Solvents with low vapor pressures and wastes with low concentrations of suspended solids appeared to be the most efficient system. The addition of 20 percent of butanol (by weight) to trichloroethane appeared to increase the extraction efficiency of trichloroethane. Bacterial counts made indicated that the solvent extraction process was affecting better than 90 percent removal of microorganisms from the waste samples. More research will be needed to completely evaluate chlorinated solvent processes for the removal of microorganisms, proteins, and other substances from sewage and other wastes. / Master of Science
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Bacterial coagulation by a chlorinated solventBlackwell, Richard Lee 16 February 2010 (has links)
This investigation has led to the following conclusions:
1. Good removals of most bacterial species were observed.
2. Increased length of settling time increased the percent removal of pure cultures.
3. The solvent coagulation process worked best at a pH very near the pH produced by the bacteria during growth.
4. There was no advantage in changing from room temperature.
S. proper surface active agents aided in the coagulation of bacteria in the solvent ooagulation process.
6. Almost all of the bacteria in suspension after the coagulation process were not viable.
7. Good removals were observed using the solvent coagulation process on mixed cultures.
8. The chlorinated solvent coagulation process shows promise for commercial operations. / Master of Science
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Antibiotic resistance, heavy metal resistance, chlorine resistance and phage typing patterns of fecal coliforms isolated from secondary effluent.Rusin, Patricia Anne. January 1989 (has links)
Antibiotic resistance profiles of fecal coliform isolated from unchlorinated and chlorinated secondary effluent were determined. Of 332 fecal coliforms isolated from chlorinated effluent a mean of 48% were multiply antibiotic resistant. In contrast, of 347 fecal coliforms isolated from unchlorinated effluent a mean of 29% were multiply antibiotic resistant. Resistance to ampicillin, cephalothin, and carbenicillin were significantly higher in the former than the latter. Randomly selected isolates survived and/or grew in sterile and unsterile effluent retaining resistance patterns for 40 days. Resistance factors were transferred in laboratory medium at frequencies from 0 to 1.2 x 10⁻² (number of recombinants/number of recipients) and in sterile neutralized tertiary effluent at frequencies from 0 to 1.0 x 10⁻⁴. Resuscitative techniques were necessary for optimal recovery of fecal coliforms from effluent using selective media. Antibiotic resistance patterns of fecal coliforms isolated from unchlorinated and chlorinated effluent was not associated with chlorine or heavy metal resistance. Multiply antibiotic resistant fecal coliforms from chlorinated effluent were significantly less sensitive to lytic phage than multiply antibiotic sensitive fecal coliforms from unchlorinated effluent (p < .05). Using group discriminate analysis of data, phage typing techniques were shown to be a potential tool for tracing fecal contamination of groundwater.
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