Showing papers on "Effluent published in 2008"

Reproductive disruption in fish downstream from an estrogenic wastewater effluent.

Abstract: To assess the impact of an estrogenic wastewater treatment plant (WWTP) effluent on fish reproduction, white suckers (Catostomus commersoni) were collected from immediately upstream and downstream (effluent site) of the city of Boulder, CO, WWTP outfall. Gonadal intersex, altered sex ratios, reduced gonad size, disrupted ovarian and testicular histopathology, and vitellogenin induction consistent with exposure to estrogenic wastewater contaminants were identified in white suckers downstream from the WWTP outfall and not at the upstream site. The sex ratio was female-biased at the effluent site in both the fall of 2003 and the spring of 2004; the frequency of males at the effluent site (17–21%) was half that of the upstream site (36–46%). Intersex white suckers comprised 18–22% of the population at the effluent site. Intersex fish were not found at the upstream site. Chemical analyses determined that the WWTP effluent contained a complex mixture of endocrine-active chemicals, including 17β-estradiol (E2) 1...

Handbook of Water and Wastewater Treatment Plant Operations

Abstract: Water and Wastewater Operations: An Overview Current Issues in Water and Wastewater Treatment Operations Water/Wastewater Operators Upgrading Security Water/Wastewater References, Models, and Terminology Water/Wastewater Operations: Math and Technical Aspects Water/Wastewater Math Operations Blueprint Reading Water Hydraulics Fundamentals of Electricity Hydraulic Machines: Pumps Water/Wastewater Conveyance Characteristics of Water Basic Water Chemistry Water Microbiology. Water Ecology Water Quality Biomonitoring, Monitoring, Sampling, and Testing Water and Water Treatment Potable Water Source Watershed Protection Water Treatment Operations Wastewater and Wastewater Treatment Wastewater Treatment Operations Appendix A. Answers to Chapter Review Questions Appendix B. Formulae Index

Analysis of ecologically relevant pharmaceuticals in wastewater and surface water using selective solid-phase extraction and UPLC-MS/MS.

Abstract: A rapid and sensitive method has been developed for the analysis of 48 human prescription active pharmaceutical ingredients (APIs) and 6 metabolites of interest, utilizing selective solid-phase extraction (SPE) and ultraperformance liquid chromatography in combination with triple quadrupole mass spectrometry (UPLC-MS/MS). The single-cartridge extraction step was developed using a mixed mode reversed-phase/cation-exchange cartridge (Oasis MCX) and validated in both wastewater effluent and surface water. Recoveries for the majority of compounds ranged from 80% to 125%, with relative standard deviations generally below 15%. Analytes were quantified using a multiple injection analysis with four chromatographic runs, with a combined run time of 48 min and SPE-UPLC-MS/MS method detection limits ranging from 1.0 to 51 ng/L. The analysis of seven wastewater effluents and one surface water sample revealed at least one detection for 38 of the 54 compounds, with effluent concentrations ranging from 7 to 2950 ng/L and surface water concentrations ranging from 10 to 140 ng/L. This initial data demonstrates that a significant number of the selected target analytes are present in wastewater treatment plant discharges.

Simultaneous nitrification, denitrification, and phosphorus removal from nutrient‐rich industrial wastewater using granular sludge

Abstract: The biological removal of nitrogen and phosphorus from nutrient-rich abattoir wastewater using granular sludge has been investigated. A lab-scale sequencing batch reactor, seeded with granular sludge developed using synthetic wastewater, was operated for 13 months under alternating anaerobic and aerobic conditions. It is demonstrated that the granules could be sustained and indeed further developed with the use of abattoir wastewater. The organic, nitrogen, and phosphorus loading rates applied were 2.7 gCOD L-1 day-1, 0.43 gN L-1 day-1, and 0.06 gP L-1 day-1, respectively. The removal efficiency of soluble COD, soluble nitrogen and soluble phosphorus were 85%, 93%, and 89%, respectively. However, the high suspended solids in the effluent limited the overall removal efficiency to 68%, 86%, and 74% for total COD, TN, and TP, respectively. This good nutrient removal was achieved through the process known as simultaneous nitrification, denitrification, and phosphorus removal, likely facilitated by the presence of large anoxic zones in the center of the granules. The removal of nitrogen was likely via nitrite optimizing the use of the limited COD available in the wastewater. Accumulibacter spp. were found to be responsible for most of the denitrification, further reducing the COD requirement for nitrogen and phosphorus removal. Mineral precipitation was evaluated and was not found to significantly contribute to the overall nutrient removal. It is also shown that the minimum HRT in a granular sludge system is not governed by the sludge settleability, as is the case with floccular sludge systems, but likely by the limitations associated with the transfer of substrates in granules. Biotechnol. Bioeng. 2008;100: 529-541. © 2007 Wiley Periodicals, Inc.

Treatment of paper pulp and paper mill wastewater by coagulation–flocculation followed by heterogeneous photocatalysis

Abstract: In this work is investigated the combined treatment of post-bleaching effluent from a cellulose and paper industry. The biodegradability index determined by the biochemical oxygen demand (BOD)/chemical oxygen demand (COD) ratio of in natura sample was 0.11, which implies little biodegradability and that it may not be discharged to the environment without previous treatment. First, the effluent was submitted to the coagulation–flocculation treatment applying FeCl 3 as the coagulating agent and chitosan as an auxiliary. In sequence, the aqueous soluble phase obtained from the first treatment was submitted to a UV/TiO 2 /H 2 O 2 system using mercury lamps. The optimized coagulation experimental conditions were chosen: pH 6.0, 80 mg L −1 of FeCl 3 ·6H 2 O, and 50 mg L −1 of chitosan. The optimized photocatalysis conditions were: pH 3.0 in 0.50 g L −1 of TiO 2 and 10 mmol L −1 of H 2 O 2 . COD values for the in natura sample was 1303 mg L −1 and after the optimized conditions of coagulation without chitosan and in chitosan presence were 545 and 516 mg L −1 , respectively. Effluent turbidity decreased sharply after coagulations (from 10 FTU of in natura samples to 2.5 FTU without chitosan and 1.1 FTU with chitosan). Similarly, a decrease was observed for concentrations of N-ammoniac, N-organic, nitrate, nitrite, phosphate, and sulfate ions after coagulation. Additionally, it was observed an absorbance reduction of 90% at the wavelength of 500 nm and of 70–80% in regions corresponding to aliphatic and aromatic groups (254, 280, and 310 nm). The use of chitosan for quantitative purposes was not so efficient; however, it improves sedimentation and compaction. COD results of photolyzed samples by UV/H 2 O 2 were 344 mg L −1 , UV/TiO 2 326 mg L −1 , and UV/TiO 2 /H 2 O 2 246 mg L −1 . The reduction in absorbance intensity was approximately 98% for aliphatic and aromatic chromophores, and 100% for chromophores absorbing at 500 nm with color disappearance. During photodegradation, SO 4 2− was formed (∼340 mg L −1 for the coagulated sample to ∼525 mg L −1 ) suggesting again the mineralization of the pollutant. The combined method (coagulation followed by photocatalysis) resulted in a biodegradability index of 0.71, transparency, and absence of color and odor in the treated water, suggesting again good water quality. This result is reinforced by the toxicity studies employing Artemia salina bioassay, which showed that an expressive decrease in toxic pollutants in effluents after treatment, mainly by combined processes. The wastewater treatment carried out in association at optimized experimental conditions provided good results.

Ozonation and Advanced Oxidation Treatment of Emerging Organic Pollutants in Water and Wastewater

Abstract: A vast number of persistent organic pollutants have been found in wastewater effluent, surface water, and drinking water around the world. This indicates their ineffective removal from water and wastewater using conventional treatment technologies. In addition to classical persistent organics such as organochlorine insecticides, solvents, and polychlorinated biphenyls, a growing number of emerging pollutants of both synthetic and natural origins have been identified as major environmental pollutants in recent years. A variety of advanced and conventional treatment options have been suggested for the removal and/or destruction of these persistent organics in water and wastewater, such as chemical oxidation, activated carbon adsorption, and membrane filtration. Of these options, chemical oxidation using ozone, alone or in combination with additional physical/chemical agents (i.e., advanced oxidation), has been proved a highly effective treatment process for a wide spectrum of emerging aqueous organic pollut...

Energy production from agricultural residues: High methane yields in pilot-scale two-stage anaerobic digestion

Abstract: There is a large, unutilised energy potential in agricultural waste fractions. In this pilot-scale study, the efficiency of a simple two-stage anaerobic digestion process was investigated for stabilisation and biomethanation of solid potato waste and sugar beet leaves, both separately and in co-digestion. A good phase separation between hydrolysis/acidification and methanogenesis was achieved, as indicated by the high carbon dioxide production, high volatile fatty acid concentration and low pH in the acidogenic reactors. Digestion of the individual substrates gave gross energy yields of 2.1–3.4 kWh/kg VS in the form of methane. Co-digestion, however, gave up to 60% higher methane yield, indicating that co-digestion resulted in improved methane production due to the positive synergism established in the digestion liquor. The integrity of the methane filters (MFs) was maintained throughout the period of operation, producing biogas with 60–78% methane content. A stable effluent pH showed that the methanogenic reactors had good ability to withstand the variations in load and volatile fatty acid concentrations that occurred in the two-stage process. The results of this pilot-scale study show that the two-stage anaerobic digestion system is suitable for effective conversion of semi-solid agricultural residues as potato waste and sugar beet leaves.

Assessment of heavy metal accumulation in macrophyte, agricultural soil, and crop plants adjacent to discharge zone of sponge iron factory

Abstract: The present study deals with the characterization of effluent released from sponge iron industries and distribution of heavy metals in soil and macrophytes near to effluent discharge channel. Apart from this, accumulation of heavy metals in nearby soil and vegetation system irrigated with effluent-contaminated water is also the subject of this study. Physico-chemical analysis of effluent reveals that the concentration of total suspended solids (TSS), total hardness (TH), iron (Fe2+), and oil and grease are greater than the IS (1981) norms for discharge of water into inland water body. The soil along the sides of the effluent channel also shows higher concentration of heavy metals than the background soil. The enrichment of the heavy metals are in the order of Chromium (Cr) > Iron (Fe) > Manganese (Mn) > Zinc (Zn) > Copper (Cu) > Cadmium (Cd). Macrophytes growing along the sides of the effluent channel also show significant accumulation of heavy metals almost in the same order as accumulated in soil. Higher uptake of heavy metals by these varieties reveals that these species can be used for future phytoremediation. The effluent as well as contaminated water is extensively used for irrigation for growing vegetables like tomato (Lycopersicon esculatum) in the surrounding areas. Heavy metal accumulation in this agricultural soil are in the sequence of Cr > Fe > Mn > Zn > Cu > Cd. More or less similar type of accumulation pattern are also found in tomato plants except Fe and Zn exceeding Cr and Mn. Transfer Factor of heavy metals from soil to tomato plants (TFS) shows average value of <1, suggesting less uptake of heavy metals from soil. Among the plant parts studied, fruit shows least accumulation. Although tomato plants show some phenotypic changes, the survival of tomato plants as well as least accumulation of metals in fruit reveals their tolerance to heavy metals. Therefore it may be suggested that this plant can be grown successfully in the heavy metal contaminated soil. Further research work on in situ toxicity test will be necessary in order to identify the most resistive variety on this particular type of contaminated site.

Environmental performance of wastewater treatment plants for small populations

Abstract: Life cycle assessment (LCA) is an environmental tool which allows the calculation of all the environmental loads related to a process/product/service. In the present work, LCA was applied to analyze the environmental impact of different technologies for wastewater treatment in small populations. In this study, 13 wastewater treatment plants (WWTPs) of less than 20,000 population equivalent (p.e.) located in Galicia (NW Spain) were inventoried. The results of the evaluation of the environmental impact are expressed in terms of diverse impact categories. Normalization identified eutrophication, mainly as P-PO43−, N-NH4+ and organic load as chemical oxygen demand (COD) in the treated effluent, and terrestrial ecotoxicity, due to the heavy metals content in the sludge, as the most significant categories for all WWTPs. Electricity use plays an important role in five of seven impact categories and presents the highest importance in four of them. When comparing technologies, secondary treatment technologies such as biodenipho and aerobic–anoxic treatment resulted in a lesser environmental impact than extended aeration. The operation of the plants has large contribution on the impact, especially for those that make use of extended aeration.

Decolorization, cytotoxicity, and genotoxicity reduction during a combined ozonation/fungal treatment of dye-contaminated wastewater.

Abstract: In view of compliance with increasingly stringent environmental legislation imposed by regional, national, and supranational (e.g., European Union) authorities, innovative environmental technologies for the treatment of dye-contaminated effluents are necessary in the color industry. In this study, effluents of an industrial dye producer were subjected to distinct treatment trains following an initial qualitative characterization. The effectiveness of ozonation and a treatment using white rot fungi (WRF) and their enzymes were compared with respect to parameters such as residual color, toxicity on human cells, and genotoxicity. A combined ozonation/WRF process was also investigated. The effluent exhibited significant toxicity that was reduced by only 10% through ozonation, whereas the fungal treatment achieved a 35% reduction. A combined treatment (ozone/WRF) caused an abatement of the toxicity by more than 70%. In addition, the initial genotoxicity of the effluent was still present after the ozone treatment, while it was completely removed through the fungal treatment.