Showing papers on "Effluent published in 1997"
TL;DR: The induction of vitellogenin synthesis in caged male trout placed at various distances downstream of the effluent entry point was used as a biomarker of estrogen exposure, and it is suggested that these chemicals probably account for the estrogenic activity of this river.
Abstract: It was recently demonstrated that most, if not all, effluents of sewage-treatment works (STWs) in the United Kingdom are estrogenic to fish. As many STWs discharge into rivers, it is possible that some stretches of rivers downstream of where the effluent enters might also be estrogenic. To assess this possibility, the induction of vitellogenin synthesis in caged male trout placed at various distances downstream of the effluent entry point was used as a biomarker of estrogen exposure. Individual discharges into five rivers in England were studied. In four cases, fish placed in the neat effluent, or close to where it entered a river, showed very marked and rapid increases in their plasma vitellogenin concentrations, demonstrating that the effluent was estrogenic. In two of these four cases, none of the downstream sites were estrogenic, whereas in one of the four, fish placed at a site 1.5 km downstream did respond by synthesizing appreciable amounts of vitellogenin, although sites further downstream were not estrogenic. The situation in the fourth river was quite different; not only was the effluent extremely estrogenic (a maximum vitellogenin response in the mg/ml range was attained), but so were all the other study sites on the river, the last of which was 5 km downstream of where the effluent entered. This particular river receives trade effluent from wool-scouring mills, which contains much higher concentrations of alkylphenolic chemicals than any of the other discharges studied. It is suggested that these chemicals probably account for the estrogenic activity of this river. The final (fifth) river showed no estrogenic activity, not even in the neat effluent. This discharge comes from a very small STW, which receives no trade waste, and one or both of these factors may account for why the effluent (and hence the river) was not estrogenic.
645 citations
TL;DR: In this paper, the feasibility of ammonium removal from sludge digestion effluents with the Anammox process was demonstrated using a synthetic wastewater, using a fixedbed reactor and a fluidised-bed reactor were suitable reactor configurations.
564 citations
TL;DR: In this paper, an electrochemical method, chemical coagulation and ion exchange were used to remove color, turbidity and COD concentration of the wastewater effluent from the secondary wastewater treatment plant of a dyeing and finishing mill.
288 citations
TL;DR: In this article, the spectral signatures (both absorption and fluorescence) of settled sewage samples collected as 24-h composites from three different treatment works were found to be similar, having an absorption band at around 280 nm and a fluorescence maximum at 340 nm (using 280 nm excitation).
232 citations
TL;DR: The biodegradability of the widely used anti-tumour agent ifosfamide was assessed with the modified Zahn-Wellens test and a test simulating biological sewage treatment, indicating that no adsorption, biodegradation or other elimination of IF took place to any noticeable extent.
230 citations
TL;DR: In this paper, an aerated filter with seeded expanded shale and an anoxic filter packed with plastic media, were operated using settled sewage feed, and iron (II) sulphate heptahydrate solution was dosed onto the top of the filter at varying ratios of total phosphorus to iron.
196 citations
TL;DR: The mutagenic and cancerogenic antineoplastic agent cyclophosphamide (CP) is released into sewage water by cancer patient excretion and in an attempt to assess the contribution of CP to the genotoxicity detected in hospital waste water in a recent study the effects of CP in the umuC test were investigated.
195 citations
TL;DR: In this article, the effectiveness of 12 different adsorbents, originating from waste materials, were used to treat an effluent, of complex composition, from a chemical works, and the effectiveness was measured in terms of its effect on the colour (absorbance at 450 nm) and COD levels of the effluent.
184 citations
TL;DR: The results of two pilot studies of an immersed membrane activated sludge process are presented in this paper, which involves coupling a bioreactor with effluent separation by microfiltration hollow fibres immersed directly in the bioreactors.
182 citations
TL;DR: In this article, the authors studied the survival and transport of a model enterovirus (BE-1) and faecal coliform bacteria in four on-site wastewater treatment systems (three conventional and one low pressure, small pipe diameter, pumped system) located in sandy soils typical of the coastal plains.
154 citations
TL;DR: In this paper, a treated effluent was used for eggplant (aubergine) irrigation through a trickle system at As-Samra experimental site, where the crop and soil were tested for pathogenic pollution.
TL;DR: The average concentrations of Σ13 PCBs in raw wastewater and treated wastewater were 4.3 and 1.4 ng/l, respectively, for PAHs, while the average concentrations for raw wastewater were 1.5 and 0.4 μg/l respectively as mentioned in this paper.
TL;DR: In this paper, a series of filter and drip emitter clogging trials was set up to seek solutions to the problems arising from the presence of suspended particles, algae, zooplankton and other organisms in the reservoirs, as well as to prevent clogging in the supply lines and in downstream sections of the drip laterals.
TL;DR: In this paper, the authors examined the potential of a biological activity control system (BACS) for BAC in comparison to granular activated carbon (GAC) for the treatment of potable water and showed that the lifetime of a GAC filter can be significantly extended by maintaining an active biofilm that has to be controlled in order to avoid filter clogging.
TL;DR: The results indicate the potential for using microalgal species grown on raceway surfaces for wastewater treatment with ammonium and orthophosphate removal remained unaltered during the diurnal cycle.
TL;DR: In this article, the theoretical basis and limitations of magnesium ammonium phosphate precipitation are investigated and experimentally tested for leather tanning industry for both segregated flows containing high ammonia concentrations and combined flows, and the resulting ammonia concentration of MAP precipitation on combined wastewater is at the level of domestic wastewater which eliminates the need of further nitrogen removal in the biological treatment and provides an effluent quality acceptable for the public sewer.
TL;DR: In this paper, anaerobic treatment of organic wastes is the most optimal treatment system, reducing the organic content, destructing toxicants and yielding energy in the form of biogas which can be used for heating and electricity production.
Abstract: Large amounts of organic waste are generated from household, agriculture and industry today. The major part of the waste from industry and households is deposited in landfills, an undesirable solution, because landfills fill up landscapes and leach pollutants into the groundwater. Furthermore, special wastes, such as wastewaters from olive oil processing, are produced in large amounts in concentrated areas mainly in Mediterranean countries. Treatment of oil mill effluent (OME) still presents a problem, which has not been solved to date. If not treated, this waste imposes a great environmental hazard, due to the very high organic chemical oxygen demand (COD) loads. Anaerobic treatment of organic wastes is the most optimal treatment system, reducing the organic content, destructing toxicants and, at the same time, yielding energy in the form of biogas which can be used for heating and electricity production. Several investigators have studied anaerobic degradation of OME and obtained COD-reductions up to approx. 80% [4, 5, 6, 13]. However, especially at high feed concentrations, the process proved probably unstable due to the inhibitory effect of phenols, lack of ammonia and due to the low alkalinity of OME. In order to overcome the above problems, the OME was diluted with water, and urea was added as nitrogen supplement [7, 12]. Furthermore, the alkalinity of the reactor content was often adjusted by NaHCO3, NaOH or Ca(OH)2 [6, 7]. However, dilution of OME with water results in unnecessary large effluent volumes, and additions of chemicals is not economically and environ-mentally desirable.
TL;DR: In this paper, the authors investigated the dissolved organic load of tannery wastewater and of the effluents of an anaerobic and aerobic treatment over a 2-year period, and the average dissolved organic carbon content (DOC) of raw wastewater is 900 mg 1−1, corresponding to a discharge of 23 kg DOC t−1 raw hide.
TL;DR: The amount of solids produced in a typical recirculating aquacultural system can be estimated using an equation presented in this paper, which shows total suspended solids (TSS) is the major pollutant of the sludge produced.
Abstract: Waste discharge from recirculating aquacultural systems is typically in the form of sludge composed of partially stabilized excreta, uneaten food particles, and bacterial growth. The amount of solids produced can be estimated using an equation presented in this paper. In a typical recirculating system, total suspended solids (TSS) is the major pollutant of the sludge produced. The production of TSS ranges from 10 to 30% of the feeding rate on a dry weight basis. The ratio of 5-d biochemical oxygen demand to total suspended solids (BODS/TSS) of the sludge ranges from 0.10 to 0.2, the total Kjeldahl nitrogen (TKN) content of the TSS ranges from 4 to 6%, and total phosphorus ranges from 0.2 to 2%.
The nature of the waste and the economics of the treatment processes dictate the disposal of aquacultural sludge. Effective clarification of aquacultural waste is critical in reducing sludge volume. Using lagoons for stabilization and storage is the most practical option. While direct disposal by land application seems feasible for rural areas with dry climates, additional stabilization/storage in a lagoon with eventual disposal through land application seems most feasible for a variety of conditions. The effluent produced from the sludge treatment processes can be used for irrigation or for direct discharge after further polishing (treatment).
TL;DR: In this paper, the authors evaluated the treatability of raw sewage in a temperate climate (wintertime around 10-20°C) using an upflow anaerobic sludge blanket (UASB) reactor and the hanging sponge cubes process.
TL;DR: In this article, a single tank Sequencing Batch Reactor (SBR) was used for abattoir (slaughterhouse) effluent treatment and the results from the laboratory work have been excellent but have to be confirmed in the pilot plant studies.
TL;DR: In this paper, the effluent generated by the Chilean fishmeal industry during hydraulic unloading of fish from ships is assayed as anaerobic inocula to purify this saline effluent.
TL;DR: A new Moving Bed Biofilm Reactor (MBBR) has been developed, where the biomass is attached to small plastic elements that move freely along with the water in the reactors as mentioned in this paper.
TL;DR: In this paper, the results from a new technique are presented in which the vinasse from beet molasses is treated by electrolysis, and the results obtained have shown that the treatment depends on the catalytic activity of the anode used, the COD loading rates and the pH of the solution.
TL;DR: In this paper, the authors describe the design, construction and the monitoring of a vertical-flow Reed Bed Treatment System (RBTS) which achieves tertiary nitrification of the effluent from a biological filter, treating the sewage flow from a population of about 200 people.
TL;DR: In this article, the effects of dairy, pig, or sewage effluent and other materials containing phosphorus (P) on their P sorption characteristics, using the Langmuir equation to estimate values of both sorption capacity and sorption strength.
Abstract: Two groups of soils were examined to determine the effects of dairy, pig, or sewage effluent and other materials containing phosphorus (P) on their P sorption characteristics, using the Langmuir equation to estimate values of both sorption capacity and sorption strength. There were 19 soils (0-15 cm) from 6 sites in the Williams River catchment and 3 soils (0-100 cm) from Bermagui, all from coastal New South Wales. Effluent usually decreased P sorption capacities of the Williams River soils, and in 3 soils the capacities were reduced to zero. Sorption strength was reduced substantially by effluent treatment in all soils except one, which had received effluent for only 3 years. Sorption strength, but not necessarily capacity, was also lower after treatment with poultry manure or chicken litter than after treatment with superphosphate only. Where effluent did not decrease sorption capacity there was a substantial increase in total carbon and iron, both of which could increase sorption capacities. After 3 years of effluent treatment of the Bermagui soil, sorption capacities had been reduced in the top 70 cm depth, the extent of the reduction varying from 17% at 0-7 · 5 cm depth to 38% at 40-70 cm depth. Sorption strength was reduced in the top 40 cm depth only. After 12 years of effluent treatment, sorption capacities and strength had also decreased at the deeper sampling depths (to 100 cm), and the average reduction in capacity was about 40%. These results suggest that P leaching will begin well before the total sorption capacity has been saturated. There was a direct and significant correlation between the sorption strength of the untreated soil and the percentage saturation reached before leaching began. Further saturation of the sorption complex appears to be slow after this degree of saturation has been reached, and it seems that P leaching exceeds adsorption during this phase. There was also a negative correlation between sorption strength and KCl-soluble P in all soils, suggesting that soil P solubility and potential saturation are both controlled by this characteristic.
TL;DR: In this article, leachates from a municipal solid waste landfill were treated by anaerobic filter (AF) and two-stage activated sludge (AS) for the removal of ammonia.
TL;DR: In this paper, two methods were tested to achieve denitrification also in both systems, one is a one-stage system, system B has two stages operated in series, and the results showed that the highest elimination rates could be achieved with system B (dosage of methanol) during experimental stage 1 (intermittent loading four times a day).