Showing papers on "Effluent published in 1995"
TL;DR: Before mangroves can be used to strip shrimp pond effluent more research is required on the effects that high ammonia and particulate organic matter loads in Pond effluent have on nutrient transformations in mangrove sediments and on forest growth.
Abstract: Preliminary estimates of the ratio of mangrove forest: shrimp pond area necessary to remove nutrients from shrimp pond effluent are made using budgets of nitrogen and phosphorus output for semi-intensive and intensive shrimp ponds combined with estimates of total net primary production in Rhizophora-dominated mangrove forests in tropical coastal areas. If effluent is delivered directly to mangrove forest plots, it is estimated that, depending on shrimp pond management, between 2 and 22 hectares of forest are required to filter the nitrogen and phosphorus loads from effluent produced by a 1 hectare pond. While such ratios may apply to small scale, integrated shrimp aquaculture - mangrove forestry farming systems, the variability in mangrove hydrodynamics makes it difficult to apply such ratios at a regional scale. Before mangroves can be used to strip shrimp pond effluent more research is required on the effects that high ammonia and particulate organic matter loads in pond effluent have on nutrient transformations in mangrove sediments and on forest growth.
222 citations
TL;DR: In this article, quantitative and efficient methods for the determination of 4-nonylphenol (4-NP) in sewage treatment plant (STP) effluent and sludge samples were developed.
Abstract: Quantitative and efficient methods for the determination of 4-nonylphenol (4-NP) in sewage treatment plant (STP) effluent and sludge samples were developed. For effluent, the 4-NP was converted, in situ, into its acetyl derivative with acetic anhydride in the presence of a base. In the case of sewage sludge, 4-NP was subjected to supercritical carbon dioxide extraction and on-line acetylation during the extraction stage. After a silica gel column cleanup, sample extract was analyzed by capillary column gas chromatography/mass spectrometry in the selected ion monitoring mode. Recoveries of 4-NP in spiked samples (1 and 10 μg/L for effluent and 5 and 50 μg/g for sludge) were 93% or above with relative standard deviations better than 5%. Detection limits for 4-NP were 0.1 μg/L for effluent and 0.1 μg/g for sludge. These methods were applied to the determination of 4-NP in samples collected from Toronto and vicinity STPs. Concentrations of 4-NP from 100 μg/g in sludge were found.
183 citations
TL;DR: Mixed bacterial cultures from a wide variety of habitats were shown to be able to decolorize the diazo-linked chromophore of a highly coloured industrial effluent from the manufacture of nitrated stibene sulphonic acid.
144 citations
TL;DR: It was found that as the abundance of each species population increased, both BOD5 and suspended solids from effluents tended to a particular range of values (the optimal range) whereas the standard deviation diminished, suggesting that ciliates are good indicators between 4 and 18 ppm in activated sludge plants.
143 citations
TL;DR: In this paper, an energy balance is presented for a second generation Advanced Integrated Wastewater Pond System (AIWPS) prototype at the University of California, Berkeley, Environmental Engineering and Health Sciences Laboratory in Richmond, California.
137 citations
TL;DR: Water use efficiency (WUE) and yield of wheat were determined in a field experiment using different irrigation waters, with and without nitrogen fertilizer on a sandy to loamy sand soil during 1991–1992 and 1992–1993 and it was concluded that application of 150–225 kg N ha−1 for well water irrigation and 75–150 kg N £1 for aquaculture effluent irrigation would be sufficient to obtain optimum grain yield and higher WUE of wheat in Saudi Arabia.
115 citations
TL;DR: In this article, the influence of high biomass concentration on the operating conditions of a newly developed high-performance bioreactor, the impinging-stream loop reactor, combined with membrane filtration is discussed.
103 citations
TL;DR: In this article, an advanced primary treatment was applied to the wastewater from the Valley of Mexico, which is a mixture of domestic and industrial discharges and rainfall for irrigation purposes on a surface of 85,000 ha.
94 citations
TL;DR: Different effluent streams of a small pulp mill utilizing agriresidues were characterized for their pollution load and were decolorized with the white rot fungus Trametes versicolor strain B7, allowing its use in large amounts and eliminating the problem of recycling the biomass.
92 citations
TL;DR: In this paper, the performance and kinetics of the activated sludge process treating wastewaters of freshwater and salinewater (10 g/l NaCl and 30 g/L NaCl) origin were investigated using bench-scale, completely mixed reactors operated at different biological solids retention times (BSRT9s) in the range of 3 to 20 d and organic loadings in the ranges of 0.5 to 2.0 kg COD/kg VSS.
89 citations
TL;DR: In this paper, the competitive effect of various substituted phenols on the carbonaceous adsorbent developed from fertilizer waste, has been studied using the Langmuir model for bisolute systems and also by the Jain and Snoeyink modified model.
TL;DR: In this article, ozone and ozone/hydrogen peroxide were used to remove preservative 1.1.1-trichloro-2-methyl-2propanol (TCMP) from pure aqueous solutions.
TL;DR: In this paper, the results of field studies in Tucson, Arizona, to estimate the soil aquifer treatment (SAT) effectiveness of a 5.7-ha water spreading facility, the Sweetwater Underground Storage and Recovery Facility, were analyzed for pathogens.
Abstract: This paper summarizes the results of field studies in Tucson, Arizona, to estimate the soil aquifer treatment (SAT) effectiveness of a 5.7-ha (14-acre) water spreading facility, the Sweetwater Underground Storage and Recovery Facility. Groundwater samples collected from the facility during 1989 to 1990 were analyzed for pathogens. A specific basin was selected during the 1990 to 1991, 1991 to 1992, and 1992 to 1993 recharge seasons for sampling source water (tertiary effluent), pore-liquid samples from the vadose zone, and groundwater during recharge. These samples were analyzed for the nitrogen species, dissolved organic carbon (DOC), and total organic halide (TOX). The results showed that the site provides effective SAT. Enteroviruses were completely removed during travel in the 37-m (120-ft) thick vadose zone. No Giardia ware detected in any of the groundwater samples. The DOC and TOX were reduced by 92% and 85%, respectively. After leaching of indigenous nitrogen from the vadose zone, total nitrogen was reduced by approximately 47% during recharge. Near-surface anaerobic conditions promote denitrification
ENEA1
TL;DR: In this article, a new downflow-upflow hybrid reactor (DUHR) has been designed for anaerobic treatment of raw cheese whey, achieving Bv values around 10 g COD·1−1·d−1, with 98% COD converted to gas and effluent soluble COD values close to 1,000 ppm; no external addition of alkalinity is required to maintain a stable pH that was constantly around 6.5-6.7 in the downflow pre-acidification chamber and around 7.5 in the bio-m
TL;DR: In this paper, a new HPLC method for the automatic determination of aromatic sulfonates in aqueous samples is presented, which is suited for the trace-level determination of a wide variety of benzene, naphthalene, anthraquinone and stilbene sulfonate.
Abstract: A new HPLC method for the fully automatic determination of aromatic sulfonates in aqueous samples is presented. The analytical procedure consists of an on-line combination of ion-pair extraction (IPE) and ion-pair chromatography (IPC), both using RP-C18 solid-phase material and a tetrabutylammonium salt as ion pairing reagent. Experimental details and performance data are given. This method is suited for the trace-level determination of a wide variety of benzene, naphthalene, anthraquinone and stilbene sulfonates. Detection limits for surface water using a diode-array detector are in the sub-ppb range. For naphthalene sulfonates a very good selectivity and minimal detectable limits of 0.02 μg/L or even lower can be achieved. So far, this method has been successfully applied to waste water, river water, bank filtrate, and water from different steps of drinking water production. The fate of several aromatic sulfonates has been studied beginning at the effluents of industrial waste water treatment plants and ending after activated carbon filtration in a water works. Napthalene-1,5-disulfonate (NDS, Armstrong acid) and cis-4,4′-dinitrostilbene-2,2′-disulfonate (DNS) appear in the raw water of the investigated water works and therefore have to be termed as relevant to water works. In contrast to other disulfonates NDS is extremely stable to biodegradation and ozonation and it is even desorbed from a highly loaded activated carbon filter.
TL;DR: In this paper, an evaluation of the effluent treatment plant of a slaughterhouse which processes 650 head of cattle a day is presented, and several modifications in the treatment plant are proposed.
TL;DR: Gravel Bed Hydroponics (GBH) is a constructed wetland system for sewage treatment which has proved effective for tertiary treatment in the UK and secondary treatment in Egypt as mentioned in this paper.
TL;DR: Biological factors, and in particular predation, can play an important role in eliminating enteric bacteria during pond system treatment, but their efficiency is supposed to diminish significantly when there is an environmental change such as the discharge of pond system effluent into brackish water.
TL;DR: In this article, an aerobic Jet Loop Reactor (JLR) activated sludge process was used to investigate its suitability for the treatment of industrial wastewaters, specifically brewery wastewater.
TL;DR: Wyatt and Knowles as discussed by the authors used a two-stage laboratory-scale activated sludge system to degrade the mixed condensate of the AN wastes by employing a recycle system on the AN manufacturing plant.
TL;DR: In this paper, the results of pilot studies at activated sludge sewage treatment plants (STPs) in Germany, UK, Netherlands, Spain and Italy which have used the anionic surfactant, LAS, as the reference compound, is described.
TL;DR: The initial growth and development trajectories suggest that effluent-exposed mayflies may emerge sooner and at a larger size than nonexposed individuals, and further work is required to determine whether the growth stimulation occurred at the expense of future reproductive output.
Abstract: To determine the food-dependent effects of biologically treated, bleached-kraft pulp mill effluent on mayfly (Baetis tricaudatus Dodds) growth and development, mayflies were exposed to effluent for 2 weeks within artificial streams arranged in a 2 × 3 factorial design (two periphyton food levels - low, high; three concentrations - control river water, 1% effluent, 10% effluent). Although survival was not affected, the effluent had a significant stimulatory effect on growth (resulting in 20 to 50% greater body weights) and development of the wing pads. Furthermore, the initial growth and development trajectories suggest that effluent-exposed mayflies may emerge sooner and at a larger size than nonexposed individuals. A key result was that the stimulatory effects occurred within both the low- and high-food treatments. Thus, the effluent-exposed mayflies grew-faster than even the high-food control animals, which already had access to more food than they could eat throughout the experiment. This shows that the stimulatory effect of the effluent on the mayflies involved more than just an increase in food-availability due to enhanced algal growth in response to nutrients in the effluent. Three possible mechanisms for this growth-enhancement effect are that the effluent (a) increased the nutritive value of the food, (b) enhanced the palatability of the periphyton, inducing increased mayfly feeding, and/or (c) directly stimulated increased mayfly growth via hormonal or other growth-stimulation effects. Further work is required to determine whether the growth stimulation occurred at the expense of future reproductive output.
TL;DR: In this paper, a new membrane reactor concept is presented to separate bacteria from the treated effluent, where the membrane plays the role of a separator of two streams and is used at the same time as the immobilizing support for the bacteria.
Patent•
27 Sep 1995
TL;DR: A multistage treatment system (10) as discussed by the authors is a multi-stage treatment system for treating nutrient-rich water containing nitrogen compounds, phosphorus compounds, and other minerals, which consists of three or more vessels or stages (20, 30, 40).
Abstract: A multistage treatment system (10) for treating nutrient-rich water containing nitrogen compounds, phosphorus compounds and other minerals. Three or more vessels or stages (20, 30, 40) typically constitute the multistage treatment system (10). Each stage of the system is a reaction vessel (20, 30, 40) having a first zone (22, 32, 42) containing a substantially insoluble salt for precipitating phosphorus compounds and other minerals, a second zone (24, 34, 44) containing a microorganism retained on an inert substrate for converting nitrogen compounds, and a separation device (26, 36, 46) for removing precipitates from the water. The effluent from the multistage system may be further treated in ponds (60, 65, 70) cultivated with aquatic grass or in a packed algae filter (100) having a medium (108) for supporting algae growth and an artificial light source (104).
TL;DR: A significant finding of this work was that effluent concentrations > or = 2.5% caused lower egg production as well as changes in the gender balance (i.e., increased numbers of individuals with male secondary sexual characteristics) of the fish.
TL;DR: The PCR was superior to the culture and DFA methods for detecting Legionella spp.
Abstract: Reclaimed water is an important resource for areas with inadequate water supplies. However, there have been few studies on the variety of microorganisms found in this type of water, since typically reclaimed water is examined only for the presence of coliform bacteria. Many microorganisms, including the legionellae, are known to be more resistant to chlorine than are coliform bacteria. Previously, we detected > 10(3) Legionella cells per ml in primary and secondary sewage effluents and observed no significant reduction in population numbers throughout the treatment process. In this study, we detected Legionella spp. in chlorinated effluent by using an EnviroAmp Legionella PCR kit and direct fluorescent antibody (DFA) staining. However, we were not able to isolate Legionella spp. from either natural or seeded reclaimed water samples. This suggests that the Legionella spp. detected by the PCR and DFA methods may be injured or viable but nonculturable after exposure to the high residual chlorine levels typically found in this type of water source. The numbers of coliform bacteria were low (< 2 cells per 100 ml) in most reclaimed water samples and were not correlated with the presence or absence of Legionella spp. We also collected air samples from above a secondary aeration basin and analyzed them by using the PCR, DFA, and plate culture methods. Legionella spp. were detected in the air obtained from above the secondary basin with all three methods. We concluded that the PCR was superior to the culture and DFA methods for detecting Legionella spp. in environmental water samples.
TL;DR: Selenium-oxyanion-containing wastewater was treated in a laboratory-scale biological reactor system inoculated with the selenate-respiring bacterium Thauera selenatis and selenite present in the water was reduced both by the ThauERA and by a population of denitrifying bacteria also present in high numbers in the reactor system.
Abstract: Selenium-oxyanion-containing wastewater, with levels of selenite as high as 3690 μg Se/l and very low levels of selenate, was treated in a laboratory-scale biological reactor system inoculated with the selenate-respiring bacterium Thauera selenatis The wastewater contained selenite that had been removed from refinery effluent wastewater using iron-coprecipitation followed by selenite release to yield a more concentrated selenium-containing wastewater The reactor system consisted of recycling sludge-blanket (500 ml; 200 g sand) and fluidized-bed reactors (500 ml; 150 g sand) The flow rate through the reactor system was 35 ml/min The carbon source fed into the reactor was acetate (3 mM); nitrate was also present (3 mM) The selenium oxyanion levels in the wastewater were reduced by 95% T selenatis was the only selenate-reducing bacterium detected in the reactor system and it presumably reduced a portion of the selenate present in the water to selenite The selenite present in the water, and that formed by selenate reduction, was reduced both by the Thauera and by a population of denitrifying bacteria also present in high numbers in the reactor system
TL;DR: In this paper, the effect of plant and influent organic matter on nitrogen removal was investigated in four experimental surface-flow wetlands treating a nitrified meat processing effluent, including a floating mat of the plant Glyceria maxima and associated decaying plant litter.
TL;DR: Synchronous fluorescence spectra (SFS) of sewage samples from three different sewage treatment plants show well-defined and reproducible structure when recorded with an off-set wavelength of 20 nm as discussed by the authors.
TL;DR: An analytical procedure that provides total AE concentration resolved by alkyl chain length for various environmental matrices (influent, effluent, and river water) was developed and extraction and concentrate of AE was quantitative over a range of concentrations for all matrices.
Abstract: Alkyl ethoxylate alcohols (AE) are used in a wide variety of household cleaning products. In order to monitor environmental levels of AE and to determine AE removal during wastewater treatment, an analytical procedure that provides total AE concentration resolved by alkyl chain length for various environmental matrices (influent, effluent, and river water) was developed. The method utilizes a reverse-phase column to extract and concentrate AE from surface waters and wastewaters and utilizes strong anionic and cationic exchange columns to remove potential interferences. AE were reacted with hydrogen bromide to form corresponding alkyl bromide derivatives that were analyzed by capillary gas chromatography with mass selective detection. Recovery of AE from influent, treatment plant effluent, and river water was quantitative (65-102%) over a range of concentrations for all matrices. AE removal was 99% at two activated sludge treatment plants and 92% at two trickling filter plants. Total AE in low dilution (effluent to river water) surface waters downstream from wastewater treatment plants were less than 0.037 mg/L.