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Showing papers on "Effluent published in 1992"


Book
01 Jan 1992
TL;DR: In this paper, the authors present the latest views on health risks, environmental hazards and crop production potential associated with the use of treated waste water for irrigation and agriculture in seven countries under different conditions.
Abstract: This publication provides a guide for the use of treated effluent for irrigation and agriculture. It presents the latest views on health risks, environmental hazards and crop production potential associated with the use of treated waste water. It explains the basis for conventional waste water treatment processes and introduces natural biological treatment systems as viable alternatives in developing countries, particularly in hot climates. An important chapter concentrates on waste water irrigation and with water quality requirements for optimum crop production and potential impacts on soils and crops. Economic, institutional and policy issues of waste water use in agriculture are briefly discussed. Finally, waste water use experience in seven countries under different conditions is reviewed and contrasted, including the USA, Jordan, Kuwait, Tunisia, Mexico, and India

724 citations


Journal ArticleDOI
TL;DR: Measurements showed that the maximum specific growth rate µ max of heterotrophic biomass depends on temperature, reactor configuration and SRT.

398 citations


Journal ArticleDOI
TL;DR: In this article, Watershed watersheds to residential development with on-site sewage disposal represent a potential change in both the quantity and quality of nutrient inputs to coastal marine systems, with initial concentrations 100-1000-fold greater than receiving coastal waters, with inorganic N/P ratios (17/1) similar to phytoplankton growth requirements.
Abstract: Changes of land use in coastal watersheds to residential development with on-site sewage disposal represent a potential change in both the quantity and quality of nutrient inputs to coastal marine systems. Measurements of dissolved N and phosphate P in septic system effluent indicated initial concentrations 100-1000-fold greater than receiving coastal waters, with inorganic N/P ratios (17/1) similar to phytoplankton growth requirements

126 citations


Journal ArticleDOI
TL;DR: In this article, a simple model of the primary clarifier can describe dynamics of buffered influent or sludge water concentrations, and different changes in ratios of particulate fractions of COD depending on influent flows are modelled.

120 citations


Journal ArticleDOI
TL;DR: In this article, the influence of secondarily treated municipal wastewater irrigation on the chemical quality of bermudagrass (Cynodon dactylon L.) turf soil (Sonoita gravelly sandy loam/ coarse-loamy, mixed, thermic Typic Haplargid) when compared to similarly irrigated potable water plots was investigated.
Abstract: Effluent and other secondary waters have become important sources of irrigation water in the U.S. Southwest. Information is inadequate relative to potential long-term effluent irrigation effects on turfgrass and soil chemical quality. The objective of this field research was to determine the influence of secondarily treated municipal wastewater irrigation on the chemical quality of bermudagrass (Cynodon dactylon L.) turf soil (Sonoita gravelly sandy loam/ coarse-loamy, mixed, thermic Typic Haplargid) when compared to similarly irrigated potable water plots (...)

117 citations


Journal ArticleDOI
TL;DR: In this paper, the presence of NOx in the process effluent gas agrees with the experimental observation that regardless of the oxidation state of nitrogen in the starting material, the predominant effluent species of nitrogen is N2.
Abstract: Supercritical water oxidation is carried out at temperatures ca. 600 °C and pressures ca. 23 MPa, with a partial pressure of oxygen ca. 2 MPa. Both thermodynamic and kinetic calculations are consistent with the experimental observation that under these conditions, regardless of the oxidation state of nitrogen in the starting material, the predominant effluent species of nitrogen is N2. Fuel-bound nitrogen can result in nitrous oxide, a species which can persist in the process effluent gas due to kinetic limitations. The absence of NOx in the process effluent gas agrees with the low rates of reaction between N2 and O2 at supercritical water oxidation temperatures.

105 citations


Journal ArticleDOI
TL;DR: In this paper, the performance of a 1200 m3 UASB reactor treating 5000 m3 municipal waste water per day at Kanpur, India was described, where the effluent overflow gutters were provided with baffles to prevent overflow of floating material.

95 citations


Journal ArticleDOI
TL;DR: Water quality parameters were measured in influent and effluent water at 11 aquaculture facilities in Hawaii to provide a basis for analyzing the environmental impacts of warm-water Aquaculture effluent discharges.
Abstract: Ten water quality parameters were measured in influent and effluent water at 11 aquaculture facilities in Hawaii. The data were grouped into four categories based on the types of organisms cultured: freshwater fish, freshwater prawn, marine fish, and marine shrimp. Within each category, concentrations of most parameters were lognormally distributed and spanned one to two orders of magnitude. Geometric mean concentrations of suspended materials, total nitrogen, total phosphorus, and pigments were highest in effluent from freshwater prawn ponds and lowest in marine fish pond effluent. Nitrate/Nitrite and total ammonia concentrations were higher in fish pond effluent than in crustacean pond effluent. Parameter concentrations were generally higher in effluent than in influent water, with freshwater fish and prawn ponds exhibiting the greatest increases in suspended materials and pigments. In contrast, nitrate/nitrite concentrations were lower in effluent than in influent waters. These data provide a basis for analyzing the environmental impacts of warm-water aquaculture effluent discharges.

93 citations


Journal ArticleDOI
G. Bortone1, S. Gemelli1, A. Rambaldi1, A. Tilche1
TL;DR: In this paper, two 51 bench-scale SBRs were built to study a simple and reliable treatment system for piggery wastewater, where the best efficiency in N removal has been noticed in the reactor in which the feeding distribution was done in two denitrification phases, allowing a better use of the organic substrate for the denitrifying bacteria.

89 citations


Patent
20 Feb 1992
TL;DR: In this paper, clarified liquid is filtered and exposed to ultraviolet radiation, and ozone is injected into the irradiated effluent and received within a contact tower where reaction between the contaminants and ozone takes place.
Abstract: Ozonated liquid is mixed within a multi-stage clarifier system with wastewater to be treated and suspended solids are removed. The clarified effluent is filtered and exposed to ultraviolet radiation. Ozone is injected into the irradiated effluent and received within a contact tower where reaction between the contaminants and ozone takes place. The ultraviolet irradiated, ozonated, and clarified liquid is recirculated through an ozone injector and discharged through a mixer plate into a purge chamber. The purge chamber effluent is split, with a portion returning to the contact tower and passing through a second ultraviolet radiation source, and the remaining purge chamber effluent being distributed within the clarifiers. After a predetermined residence within the system, a diverter valve in the return line is operable to discharge the treated water through a carbon filter and out of the system. The recirculation of the UV irradiated ozonated liquid provides both effective solids removal and reaction of the contaminants with the ozone to produce an acceptable treated water.

89 citations


Journal ArticleDOI
TL;DR: In this paper, a partial toxicity identification evaluation (TIE) was conducted with a publicly owned treatment works (POTW) effluent that received no secondary treatment, and the effluent was consistently acutely toxic to fathead minnow (Pimephales promelas) and the cladoceran Ceriodaphnia dubia.
Abstract: A partial toxicity identification evaluation (TIE) was conducted with a publicly owned treatment works (POTW) effluent that received no secondary treatment. The effluent was consistently acutely toxic to fathead minnow (Pimephales promelas) and the cladoceran Ceriodaphnia dubia. Initial Phase I toxicity characterization and Phase II identification work with Ceriodaphnia dubia suggested that surfactants were responsible for a significant portion of the toxicity of the effluent. Subsequent experiments concerning the behavior of various mixtures of surfactants in Phase I and Phase II TIE procedures provided additional evidence that these compounds were important determinants of toxicity of the POTW effluent. Finally, measurement of two general classes of surfactants in the test effluent (anionic, nonionic) indicated that there were sufficient concentrations of these compounds to be of toxicological concern. The identification of surfactants as potentially important toxicants in a primary effluent is not particularly surprising in light of their concentrations in untreated or inadequately treated wastewater.

Patent
23 Nov 1992
TL;DR: In this paper, a process for disposing of sewage sludge comprising the steps of, (1) dewatering the sludge to produce an aqueous slurry of sludge having a solids content of about 10 to 30 wt. %; (2) simultaneously heating and shearing said dewatered sludge at about 150° F to 210° F. in the absence of air for 0.5 seconds to 60 minutes while being continuously passed through a tubular-shaped processing means containing a plurality of rotating agitators.
Abstract: A process for disposing of sewage sludge comprising the steps of, (1) dewatering the sewage sludge to produce an aqueous slurry of sewage sludge having a solids content of about 10 to 30 wt. %; (2) simultaneously heating and shearing said dewatered sewage sludge at about 150° F. to 210° F. in the absence of air for 0.5 seconds to 60 minutes while being continuously passed through a tubular-shaped processing means containing a plurality of rotating agitators, thereby producing a pumpable slurry having a viscosity of less than about 2000 centipoise; (3) dewatering the sewage sludge if necessary; (4) mixing at a temperature in the range of about ambient to 180° F. in a ribbon or in-line static mixer the slurry of sewage sludge from (2) and/or (3) with a supplemental solid carbonaceous fuel e.g. coal and/or petroleum-coke to produce a pumpable aqueous slurry of sewage sludge and supplemental fuel having a solids content in the range of about 50 to 60 wt. %; (5) mixing the slurry of sewage sludge and supplemental fuel from (4) in a steam jacketed continuous rotary disc mixer at about 180° F. to 250° F. while removing steam to produce a pumpable slurry of dewatered sewage sludge and solid fuel having a solids content of 50 to 65 wt. % and a HHV of 6,000 to 18,000 BTU/LB; and (6) burning said pumpable slurry from (5) in a partial oxidation gasifier, furnace, boiler, or incinerator to produce an effluent gas stream. In a preferred embodiment, the effluent gas stream is cleaned and purified and non-contaminating ash and slag are separated. By this process, noxious sewage sludge may be disposed of without contaminating the environment. By-product synthesis gas, reducing gas, or fuel gas may be produced.

Journal ArticleDOI
TL;DR: In this article, the authors used two UASB reactors (T and U) and a downflow tubular fixed film reactor to treat terephthalic acid plant wastewater.

Journal ArticleDOI
TL;DR: This study illustrates the successful application of EPA TIE methodologies for identifying a nonpolar organic toxicant in a complex effluent and suggests that diazinon may indicate a more widespread problem in this region of the United States.
Abstract: A toxicity identification evaluation (TIE) conducted on a municipal wastewater discharge from the southeast United States was part of a research project aimed at developing U.S. Environmental Protection Agency (EPA) TIE methods for acutely toxic effluents. The effluent consistently exhibited acute toxicity to Ceriodaphnia dubia but not to fathead minnows (Pimephales promelas). Toxicity characterization procedures revealed that the primary toxicant was a nonpolar organic. Toxicity was recovered through C18 solid-phase extraction and concentration steps. Gas chromatography–mass spectroscopy of these concentrates revealed the presence of diazinon (O, O-diethyl O-[6-methyl-2-(1-methylethyl)-4-pyrimidinyl] phosphorothioate). Diazinon concentrations in whole effluent, determined by GC analyses, correlated well with the toxicity measurements of each sample. Relative species sensitivity also implicated diazinon as the primary toxicant. This study illustrates the successful application of EPA TIE methodologies for identifying a nonpolar organic toxicant in a complex effluent. The significance of detecting diazinon at acutely toxic concentrations in municipal wastewater may indicate a more widespread problem in this region of the United States. This toxicity problem may be attributed to the chemical characteristics of diazinon and its applications.

Journal ArticleDOI
TL;DR: In this paper, anionic surfactants and their biodegradation intermediates were isolated from field samples by ion exchange and fractionated by solvent extraction and adsorption chromatography.

Patent
16 Apr 1992
TL;DR: In this paper, a method for processing manure, liquid manure and/or Kjeldahl-N containing waste water being subjected to a nitrification in an aerated reactor containing active sludge and to a denitrification in a high rate recirculation denitification reactor (13) containing a very compact biomass capable of converting nitrate to nitrogen gas.
Abstract: The invention relates to a method for processing manure, liquid manure and/or Kjeldahl-N containing waste water being subjected to a nitrification in an aerated reactor containing active sludge and to a denitrification in a high rate recirculation denitrification reactor (13) containing a very compact biomass capable of converting nitrate to nitrogen gas. The loading of the nitrification reactor (9) being controlled to obtain an optimal nitrification and denitrification, the effluent from the nitrification reactor (9) partially being passed to the denitrification reactor (13), adding a source of carbon to the effluent to be passed to the recirculation denitrification reactor (13) and passing another portion of the effluent stream from the nitrification reactor (9) to a separation step (19) to separate a sludge, the effluent from separation step (19) being passed to a discharge line denitrification reactor (37) under the addition of a carbon source if desired. The invention further relates to an apparatus constructed for this purpose.

Journal ArticleDOI
TL;DR: In this article, it is argued that initial removal and digestion of the particulate organics, in combination with treatment of the soluble organics by means of a trickling filter with thick biofilm, might constitute an optimal way of maximizing anaerobic electron flux, resulting in an overall lower final sludge production and yet still achieving a high quality, low nutrient effluent.

Patent
01 Jun 1992
TL;DR: In this article, a biological treatment system involving the use of a gas dissolving pressure vessel, a pressurized water release assembly, a pretreatment chamber, a bioreactor, an open vessel, and a post-treatment unit for both wastewater treatment and air emission control is described.
Abstract: A biological treatment system involving the use of a gas dissolving pressure vessel, a pressurized water release assembly, a pretreatment chamber, a bioreactor, an open vessel, a post-treatment unit, a sludge removal unit, and a removable gas collection and purification unit for both wastewater treatment and air emission control is described. Gases are dissolved efficiently in a water inside the pressure vessel under controlled high pressure and high rotating velocity. Chemicals, or microorganisms, or both arm dosed to an influent water producing a pretreated water containing chemical flocs and biological flocs. The bioreactor comprising a hanging biological contactor is adopted when biochemical reaction is intended. A pressurized water containing supersaturated gases is produced in the pressure vessel and than depressurized through the pressurized water release assembly becoming a depressurized water containing micro bubbles. The pretreated water containing chemical flocs or biological flocs, or both are gently mixed and held together with the depressurized water containing micro bubbles in the open vessel for separation of chemical/biological flocs to the water surface, producing a purified effluent and a waste gas. A portion of the purified effluent is recycled for gas dissolution and micro bubbles production. When necessary, the waste gas is collected, purified and recycled to the pressure vessel or the bioreactor, or both for reuse.

Journal ArticleDOI
TL;DR: In this article, a two-step strategy based on a respiration test is proposed to locate the sources of inhibition within a short time and to concentrate then on the abatement of the inhibiting wastewaters.

Journal ArticleDOI
TL;DR: ADUF R (anaerobic digestion ultrafiltration) is a membrane-assisted process for positive separation of biomass from the treated effluent as mentioned in this paper, which achieved a mean COD removal efficiency of 97%.

Journal ArticleDOI
TL;DR: In this paper, the effects of an increased loading of hydrophilic compounds on the treatment process need to be evaluated, and a declining trend in influent loadings was observed for a number of priority pollutants.

Journal ArticleDOI
TL;DR: Bacterial abundance and biomass were studied in April, July, and October 1989 at 13 stations along 300 km of the course of the river Seine, including Paris and its suburbs as mentioned in this paper.
Abstract: Bacterial abundance and biomass were studied in April, July, and October 1989 at 13 stations along 300 km of the course of the river Seine, including Paris and its suburbs. Monthly investigations were carried out at five stations downstream from Paris where the river receives the effluent of an important waste water treatment plant (Acheres). As a result of an input of allochthonous bacteria from the effluent of the plant, an increase in bacterial abundance and biomass was observed below Acheres (from about 5 × 109 to 15 × 109 cells L−1 and from 100 to 750 μg C L−1). This was followed by a rapid decrease. The allochthonous bacteria comprised a high proportion of large bacteria, which disappeared at a much higher rate than the small bacteria (0.0366 vs. 0.0125 h−1). Paradoxically, these large bacteria grew at a rate twice that of the smaller cells in culture experiments (0.129 vs. 0.065 h−1 in June and 0.118 vs. 0.071 h−1 in October). These large bacteria must therefore be subjected to intense losses (graz...

Journal ArticleDOI
TL;DR: Improved nitrification with recirculation was due to the dilution of influent biodegradable organic carbon (BOD 5 ) which occurs as a result of mixing secondary plant effluent with first stage effluent.

Patent
06 Jan 1992
TL;DR: In this paper, a process for treating an aqueous wastewater containing ammonium compounds is described, which comprises the steps of preheating a liquid influent and introducing the preheated influent, an oxygen-containing gas an the wastewater into a reaction vessel for undergoing wet oxidation.
Abstract: A process for treating an aqueous wastewater containing ammonium compounds. The process comprises the steps of preheating a liquid influent and introducing the preheated influent, an oxygen-containing gas an the wastewater into a reaction vessel for undergoing wet oxidation. An oxidized effluent is then withdrawn from the reaction vessel, which includes a gas phase containing ammonia and carbon dioxide and a liquid phase containing the ammonium compounds. The temperature of the effluent is then reduced to a temperature sufficient to condense a substantial portion of the ammonia into the liquid phase, and afterwards the remaining gas phase containing a substantial portion of the carbon dioxide is separated from the resulting liquid phase. Either prior to or subsequent to the separation the pH of the liquid phase is adjusted to a level whereby a substantial portion of the ammonia remains in the liquid phase when the liquid phase is subsequently subjected to an elevated temperature above the boiling point of water and the water content of the pH-adjusted liquid phase is then reduced by evaporation.


Journal ArticleDOI
TL;DR: The results suggest that full-scale use of immobilized bacteria can be a cost-effective and dependable technique for the biotreatment of industrial wastewater.
Abstract: Immobilized bacteria have been shown in the laboratory to effectively remove glyphosate from wastewater effluent discharged from an activated sludge treatment system. Bacterial consortia in lab columns maintained a 99% glyphosate-degrading activity (GDA) at a hydraulic residence time of less than 20 min. In this study, a pilot plant (capacity, 45 liters/min) was used for a field demonstration. Initially, activated sludge was enriched for microbes with GDA during a 3-week biocarrier activation period. Wastewater effluent was then spiked with glyphosate and NH4Cl and recycled through the pilot plant column during start-up. Microbes with GDA were enhanced by maintaining the pH at less than 8 and adding yeast extract (less than 10 mg/liter). Once the consortia were stabilized, the column capacity for glyphosate removal was determined in a 60-day continuous-flow study. Waste containing 50 mg of glyphosate per liter was pumped at increasing flow rates until a steady state was reached. A microbial GDA of greater than 90% was achieved at a 10-min hydraulic residence time (144 hydraulic turnovers per day). Additional studies showed that microbes with GDA were recoverable within (i) 5 days of an acid shock and (ii) 3 days after a 21-day dormancy (low-flow, low-maintenance) mode. These results suggest that full-scale use of immobilized bacteria can be a cost-effective and dependable technique for the biotreatment of industrial wastewater.


Patent
20 Mar 1992
TL;DR: Disclosed as discussed by the authors is a method and apparatus for the rapid identification of a solute of interest in an effluent stream, which involves separation of the solutes in the effluent and identification of the particular solutes of interest by its selective subtraction.
Abstract: Disclosed is a method and apparatus for the rapid identification of a solute of interest in an effluent stream (14). The method involves separation of the solutes in the effluent (14) and identification of a particular solute of interest by its selective subtraction from the effluent stream (14). The effluent stream (14) from a first system (12) capable of partitioning the components of the mixture is passed through a detector (16) to produce a first output (18) which describes the temporal and/or spacial sequence of the mixture components exiting the first system (12). The effluent stream (14) is then passed through a second system (20) capable of selectively extracting a solute of interest from said effluent stream (14) and is then passed through a detector (16).

PatentDOI
TL;DR: In this article, a process and device for combined oxidation of polluted water, to make it suitable for drinking, involves injection of hydrogen peroxide (pure aqueous solution or diluted) and ozone (gaseous, or ozonized oxygen or air) simultaneously and in a flow direction co-current with the circulation of the water to be treated, at the inlet of the oxidation reactor.

Journal ArticleDOI
TL;DR: In this article, column experiments were conducted to examine the removal of phosphorus and nitrogen from sewage effluent by passage through sand amended with bauxite refining residue (red mud). Red mud was neutralized with 5% gypsum.