Showing papers on "Effluent published in 1975"

Demonstration of virus in groundwater after effluent discharge onto soil.

Abstract: The survival of virus present in secondary effluents discharged into a cypress dome was studied. Isolations were made from concentrates of water drawn from 10-foot (304.80 cm) deep wells. Data presented show vertical and lateral virus movement as well as survival within the dome for 28 days during a period of heavy rains when no effluent was being applied. Due to the inefficiency of virus concentration procedures, it is proposed that much of the virus present was probably not demonstrated. A rapid, relatively inexpensive concentration technique for sewage influents and effluents is discussed.

Dynamics of nitrification in the activated sludge process.

Abstract: Renewed interest in the problems cre ated by the d scharge of nitrogenous compounds to receiving waters has focused attention on the form and concentration of nitrogen in wastewater treatment plant effluents. Most wastewater treatment plants are designed, operated, and evalu ated based on the reduction of carbona ceous 5-day biochemical oxygen demand (bod5), rather than on the total bod of the effluent (carbonaceous and nitrogenous). As a result, ammonium is the primary form of nitrogen in domestic wastewater treat ment plant effluents and is commonly found in concentrations up to 20 to 30 mg/1. If a theoretical oxygen requirement for ni trification of 4.5 mg oxygen/mg ammonium nitrogen oxidized to nitrate is assumed, an effluent with 20 mg NH4+-N/1 can exert a nitrogenous oxygen demand of up to 90 mg/1, which is considerably greater than that contributed by the ultimate car bonaceous demand of secondary biologi cal treatment plant effluents (?30 mg/1). The conversion of ammonium to nitrate within a biological treatment plant would, therefore, represent a significant improve ment in effluent quality. The activated sludge process may be used to obtain nitrification if conditions suitable for the retention and accumulation of nitrifying bacteria are maintaned. The conditions necessary for nitrification may be expressed in terms of sludge age, pH, temperature, and dissolved oxygen (do) concentration. The concentration of nitrifying bacteria will depend on their specific growth rate and on the rate at which they are discharged from the system through the effluent and waste sludge streams. Several laboratory, pilot, and full scale investigations have been conducted with nitrifying activated sludge systems and have demonstrated that high efficiencies of nitrification are obtained at sludge ages of approximately 4 days or more.1-6 It is important to note, however, that, at tem peratures less than 20 ?C, the sludge age required to maintain high nitrification ef ficiencies increases markedly. Until the recent application of mathe matical models based on kinetic principles, some of the basic concepts regarding ni trification in the activated sludge process were not clearly understood. Downing et al.1 were among the first to develop a kinetic model for nitrification in the acti vated sludge process. They concluded that consistent nitrification would be expected in activated sludge plants only if the growth rate of the nitrifying bacteria were greater than the rate of loss through the effluent and sludge wasting streams. Using this concept and experimentally determined values for growth rate coefficients, they were able to obtain reasonable predictions of the degree of nitrification in activated sludge plants.7 Although several mathematical models have been developed for the nitrifying ac tivated sludge process,1'3> 8_11 these usually have been steady-state models. Because domestic wastewater treatment plants op erate under time-varying loads, the use of steady-state models to describe these processes is inconsistent with their opera tional nature. In this regard, a full under standing of the kinetics of nitrification and the response of nitrifying systems to dy namic inputs may be necessary before more effective control of nitrification is possible. The primary objective of this research was to develop a dynamic model for nitri fication in the activated sludge process that

Unsaturated Flow During Soil Treatment of Septic Tank Effluent

Abstract: Subsurface soil disposal of septic tank effluent is governed by physical flow processes in unsaturated soil. The capacity of a soil to accept, conduct, and purify effluent cannot be expressed by percolation tests or by hydraulic conductivities at saturation alone. Field tests are available now to measure complete K-curves and application to many soils in Wisconsin has shown that four different types of curves can be distinguished. Effects of biological clogging or mechanical compaction, or puddling on infiltration into the soil are examined, considering different levels of the water table and using a simple one-dimensional flow theory. Results of in situ monitoring with tensiometers of 12 seepage systems in different soils and design criteria, some tentative, for innovative systems in a wide range of soils are considered. Use of soil survey information for purposes of extrapolation of research results from tested to untested sites is recommended.

Catalytic abatement system

Abstract: An apparatus for the thermal-catalytic abatement of hydrocarbons, carbon monoxide, nitrogen oxides and particulates from effluent gas streams. The apparatus has a preheat section wherein the effluent is heated to 400°-1000° F by hot combustion gases. The effluent and combustion gases are directed by a baffle through a filter where combustible particulates are incinerated and noncombustible particulates are collected. The baffle followed by a diffuser cone, axially located on the filter, intimately mixes the effluent with the combustion gases so as to provide uniform flow and temperature distribution of the mixed gases across the filter. The filtered gases then pass through a catalytic reactor section containing a catalyst, preferably catalyst-coated ceramic honeycombs. In the presence of the catalysts the hydrocarbons and carbon monoxide in the heated gas stream are oxidized to carbon dioxide and water and the nitrogen oxides are reduced.

Disinfection system and method

Abstract: A rapid and efficient method for disinfection of waste liquid such as sewage effluent by means of a fluid disinfecting agent, (e.g. ozone or chlorine) in which the disinfecting agent and all of the waste liquid to be treated pass through a turbulent flow zone within a limited period of time. Also disclosed is specific apparatus for carrying out the method.

Process for treating waste water containing cellulose nitrate particles

Abstract: Total removal of cellulose nitrate particles from a waste water stream is accomplished by a combination of chemical and biological treatments which result in an effluent having a greatly reduced concentration of nitrogen compounds and having an acceptable BOD. The first step in the process requires that the insoluble, non-biodegradable cellulose nitrate particles be chemically digested with alkali to produce soluble products. Following digestion, the waste stream is supplemented with domestic raw sewage and a microbially utilizable carbon source and the supplemented waste stream is subjected first to an anaerobic microbial denitrification treatment to eliminate the oxidized forms of nitrogen and then to an aerobic microbial treatment to reduce BOD and to oxidize reduced nitrogen compounds. The effluent therefrom is again supplemented with a microbially utilizable carbon source and subjected to a final anaerobic microbial denitrification to remove nitrates present in the waste water resulting from nitrification processes occurring during the aerobic treatment step.

Effects of Acute Exposure to Bleached Kraft Pulpmill Effluent on Carbohydrate Metabolism of Juvenile Coho Salmon (Oncorhynchus kisutch) During Rest and Exercise

Abstract: In the static study (no exercise), liver glycogen stores were unchanged during 12-h exposure to 0.8 of the 96-h LC50; longer exposures caused a progressive decrease to levels one fifth those of controls at 72 h. Plasma glucose levels in fish held in 0.8 LC50 effluent for 3–96 h were elevated; at 96 h, glucose had increased threefold. Mean values for plasma lactate were elevated significantly at 3, 6, 24, 72, and 96 h.In the exercise (swimming one body length per second)–rest study, muscle glycogen levels decreased 53–78% during exercise in water or effluent (0.7 LC50) for 4–12 h, and did not recover during 12-h rest in water. Muscle glycogen for fish exercised for 12 h in effluent and then rested for 4 or 12 h in effluent was lower compared to values for fish exercised in effluent and then rested in water. There was no difference in liver glycogen levels offish exercised in effluent or water for 4–12 h. Values of liver glycogen for fish exercised in effluent for 12 h and then rested for 4, 8, or 12 h in e...

Method of applying ozone and sonic energy to sterilize and oxidize waste water

Abstract: A tertiary waste water treatment system wherein the waste water is subjected to physical chemical processes. The waste water is treated with a coagulating agent, a polyelectrolyte and then is clarified in a lamina preferably of unique design. The clarified waste water is then filtered and passed through an ozonation-sonication chamber wherein the liquid flows counter to the ozone. Within the tower, the liquid is subjected to substantial levels of sonication, enough to cause cavitation, either simultaneously with or prior to encountering large concentrations of ozone. After the ozonation-sonication treatment, the effluent may be discharged or it may be passed through an ozone contact chamber.

Sanitary waste treatment plant

Abstract: A self-contained toilet and sanitary waste treatment plant that has a delivery system, a biological treatment system and a water recovery system. The delivery system includes a vacuum-type flush toilet adapted to receive flush water from the water recovery system and delivery means adapted to discharge the sanitary waste and flush water into the biological treatment system. The latter includes anaerobic digestion means, aerobic digestion means and sedimentation means for reducing the organic matter by biological treatment. The effluent from the biological treatment system is discharged to the water recovery system wherein primary and secondary filtration means are employed for reclaiming water for flush or other purposes. The primary filtration means includes ultra-filtration apparatus for separation of the effluent into a water permeate and an effluent concentrate, the former passing to the secondary filtration means for further filtration treatment and storage as flush water, and the latter passing back to the biological treatment system for further reduction by biological treatment. Controls are provided to enable the waste treatment plant to operate automatically for extended periods of time.

Sewage treatment process

Abstract: Ultrasonic energy is transmitted to sewage, including, inter alia, liquid or waste water, organic solid matter and aerobic bacteria, to reduce the liquid particle size and enrobe the reduced water particles with air to enhance the air to liquid absorption of the liquid and thereby provide (a) the aerobic bacteria with additional oxygen to utilize in the process of oxidation whereby the aerobic bacteria convert the organic solid matter to a more stable form or compound; (b) the effluent of sewage treatment plants with a higher oxygen content sufficient to aid or sustain desirable aquatic life. In a further embodiment, the liquid is first coverted to a thin film and then subjected to ultrasonic energy. In a still further embodiment, the sewage is first preheated to enhance the aerobic organism or bacteria activity. In a still further embodiment the air is preheated and/or hydrated to diminish heat loss and thus a temperature drop, by the liquid. Additionally, the synergistic effects of ultrasonic energy and ultraviolet energy are utilized to sensitize microorganisms which may then be easily destroyed by chemicals, and/or radiati on and/or other means. Still further, the synergistic effects of ultrasonic and microwave energy are utilized to decontaminate the surface of sewage liquid and solids, the ultrasonic energy is utilized to produce a humid atmosphere and the microwave energy provides surface decontamination.

Removal of heavy metal ions from wastewater

Abstract: Concentrations of undesirable heavy metals in industrial wastewater are reduced to below or very close to the most stringent aqueous discharge limits This is accomplished by forming an insoluble metal-polyelectrolyte complex which can be easily and economically removed from the effluent

Method for removing soluble selenium from acidic waste water

Abstract: Selenium is removed from solution in acidic waste water by treatment of the water with a metallic reducing agent. The invention is particularly effective for removal of selenium from zinc smelter effluent by reaction of the effluent with powdered zinc.

Process and system for treating waste water

Abstract: A process of treating raw or primary waste water using a powdered, activated carbon/aerated biological treatment system is disclosed. Effluent turbidities less than 2 JTU (Jackson turbidity units), zero TOC (total organic carbon) and in the range of 10 mg/l COD (chemical oxygen demand) can be obtained. An influent stream of raw or primary waste water is contacted with an acidified, powdered, activated carbon/alum mixture. Lime is then added to the slurry to raise the pH to about 7.0. A polyelectrolyte flocculant is added to the slurry followed by a flocculation period -- then sedimentation and filtration. The separated solids (sludge) are aerated in a stabilization sludge basin and a portion thereof recycled to an aerated contact basin for mixing with the influent waste water stream prior to or after contact of the influent stream with the powdered, activated carbon/alum mixture.

Biological denitrification and its application in treatment of high-nitrate waste water

Abstract: One method of removing nitrate nitrogen from waste water effluents appears to be biological denitrification. Considerable research regarding denitrification of municipal and agricultural waste water containing relatively low concentrations of nitrate ( 1,000 ppm NO₃-N.

Fate of nitrogen in sewage effluent applied to soil

Abstract: Natural chemical and biological reactions will remove nitrogen from sewage effluent applied to soils if the wastewater is applied in a carefully managed treatment system. Only denitrification can remove the tremendous quantities of nitrogen applied in a high-rate land filtration system where nitrogen loads may be 10 to 30 times greater than those applied in irrigation systems. Columns packed in the laboratory with loamy sand removed 80% of the nitrogen applied at infiltration rates below 6 in./day (l5 cm/day). Percent nitrogen removal decreased exponentially as the infiltration rate increased from 6 in./day - 22 in./day (l5 cm to 55 cm/day). Nitrogen was also removed by the soil columns when high-nitrate water was collected, mixed with sewage, and recycled. Nitrogen may be removed by applying sewage to soils of low permeability and allowing it to trickle slowly down grassed slopes. Removal is probably due to a combination of plant uptake, denitrification, and immobilization in microbial tissue.

Method for treating effluent resulting from the manufacture of synthetic dyestuffs and related intermediate chemicals

Abstract: A method and apparatus for treating effluent resulting from the manufacture of synthetic dyestuffs and related intermediate chemicals is provided. The effluent is subjected to equalization, chemical treatment, clarification to remove solids, further equalization and carbon adsorption to remove the color and toxic materials, followed by a secondary biological treatment which includes treatment with activated sludge and secondary clarification. The spent carbon used in the carbon adsorption is recycled to produce fresh carbon which is reused in the carbon adsorption process.

Metal concentrations in the sewage, effluents, and sludges of some southern Ontario wastewater treatment plants.

Abstract: Aluminum, barium, beryllium, bismuth, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, molybdenum, nickel, silver, strontium, vanadium and zinc concentrations in the sewage, effluents and sludges of ten southern Ontario wastewater treatment plants are reported. The efficiency for metal removal by a conventional activated sludge plant was determined. The effect of metal concentrations in receiving waters from residual metals in sewage effluents is discussed. The environmental hazards of disposing of sewage sludges with high metal content on agricultural land is considered.

Effects of the discharge of thermal effluent from a power station on Lake Wabamun, Alberta, Canada — Limnological features

Abstract: The physical and chemical aspects of Lake Wabamum have been described. Modifications to the thermal and dissolved oxygen regimes through the discharge of thermal effluent into the eastern region of the lake are discussed. This discharge has, therefore, changed the environmental conditions under which the biota exists in the eastern portion of the lake. It was also shown that this discharge of heated water had no effect upon the water chemistry while the power station itself contributed silica, in the form of fly ash, to the system. Tables of the phytoplankton, zooplankton, aquatic macrophytes, and fish are provided. From a biological and limnological stand point the lake can be classified as a moderately eutrophic lake, especially in the eastern portion.

Water Hyacinths for Upgrading Sewage Lagoons to Meet Advanced Wastewater Treatment Standards, Part 1

Abstract: Water hyacinths, Eichhornia crassipes Mart. Solms, have demonstrated the ability to function as an efficient and inexpensive final filtration system in a secondary domestic sewage lagoon during a three month test period. These plants reduced the suspended solids, biochemical oxygen demanding substances, and other chemical parameters to levels below the standards set by the state pollution control agency. The water hyacinth-covered secondary lagoon utilized in this experiment had a surface area of 0.28 hectare (0.70 acre) with a total capacity of 6.8 million liters (1.5 million gallons), receiving an inflow of 522,100 liters (115,000 gallons) per day from a 1.1 hectare (3.8 acre) aerated primary sewage lagoon. These conditions allowed a retention time of 14 to 21 days depending on the water hyacinth evapotranspiration rates. The desired purity of final sewage effluent can be controlled by the water hyacinth surface area, harvest rate, and the retention time.

Sewage treatment apparatus

Abstract: An aerobic bacteria sewage treatment apparatus using compressed air to aerate activated sludge, and to cause it to circulate about a cylindrical clarification compartment placed in the apparatus in a way to provide a zone of relative quiescence in the flowing sewage from which the clarification compartment withdraws liquid and further separates solid matter therefrom, finally delivering a very well clarified effluent, the effluent pipe being placed in the clarification compartment such that heavier particles tend to sink away from it and lighter particles tend to rise above it, whereby the effluent is substantially free of solid matter.

Bacterial degradation of motor oil.

Abstract: Oils are a problem for wastewater treatment plant ope ator About 25 percent of the organic material in waste water is lipidlike and hydrophobia1 Some of the lipidlike material is trapped with settled sludge, becomes associated with suspended particulate matter, or is present in the colloidal or dissolved state and may be discharged with the effluent The esti mated amount of oil discharged by waste water effluents is about the same as the amount of oil spilled annually in coastal waters, namely, 28,000 metric tons2 Oil derived from spills in near-shore areas, how ever, is most likely to be a refined product such as motor oil or fuel oil, rather than crude oil, the ultimate disposition of which is yet to be assessed2 This study examines the ultimate dis position of motor oil, the type of petroleum likely to be associated with nearshore dis charges and wastewater effluent The motor oil in the experiments described in this paper was subjected to degradation by naturally occurring microbial populations cultured under conditions promoting op timum degradation and simulating the natural environment