Advanced swine manure treatment and utilization in Brazil

Animal production has changed from subsistence to an industrial model, lowering production costs but giving rise to higher potential environmental impact. When the effluents are not correctly managed, serious pollution events can occur. In Brazil liquid manure is commonly stored in reception pits or covered lagoons (biodigestors), followed by land application as a biofertilizer. In some regions there is an excess of manure due to low soil support capacities, and in these cases new technologies have to be adopted to export or treat the excess effluent. Manure storage time in pits/covered lagoons and new polymers to separate the solid fraction have been studied in Brazil. Treatment technologies, like swine manure treatment systems (SMTS), have been developed from a technical and economical point of view to optimize the processes and give a technological alternative to pork producers increasing production while reducing environmental impact.     

Rural and Urban Streams: Anthropogenic Influences and Impacts on Water and Sediment Quality

The Pirapó river watershed (Paraná State, Brazil) compounds a relatively industrialized and urbanized region, undergoing great pressure from the discharge of industrial, agricultural and domestic wastes. We evaluated the environmental quality of ten streams belonging to this watershed in April and June 2008 by performing acute and chronic toxicity tests with Daphnia similis and Ceriodaphnia silvestrii from water and sediment samples. We tested the hypothesis that the streams located in urban areas are more exposed to the influence of pollutants, than those outside the city limits. In addition, we obtained the measures of physical and chemical parameters, and identified the main polluted sources. Contrary to what was expected, the rural streams were more toxic than those located in urban area. These results demonstrate that the water bodies located in rural areas are being affected by the pollution of aquatic ecosystems as far as those found in urban areas, requiring the same attention of environmental managers in relation to its monitoring. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)     

Isolation and Characterization of Chromium(VI)-Reducing Bacteria from Tannery Effluents

Two chromium-resistant bacteria (IFR-2 and IFR-3) capable of reducing/transforming Cr(VI) to Cr(III) were isolated from tannery effluents. Isolates IFR-2 and IFR-3 were identified as Staphylococcus aureus and Pediococcus pentosaceus respectively by 16S rRNA gene sequence analyses. Both isolates can grow well on 2,000 mg/l Cr(VI) (as K₂Cr₂O₇) in Luria-Bertani (LB) medium. Reduction of Cr(VI) was found to be growth-associated in both isolates and IFR-2 and IFR-3 reduced 20 mg/l Cr(VI) completely in 6 and 24 h respectively. The Cr(VI) reduction due to chromate reductase activity was detected in the culture supernatant and cell lysate but not at all in the cell extract supernatant of both isolates. Whole cells of IFR-2 and IFR-3 converted 24 and 30% of the initial Cr(VI) concentration (1 mg/l) in 45 min respectively at 37°C. NiCl₂ stimulated the growth of IFR-2 whereas HgCl₂ and CdCl₂ significantly inhibited the growth of both isolates. Optimum temperature and pH for growth of and Cr(VI) reduction by both isolates were found to be between 35 and 40°C and pH 7.0 to 8.0. The two bacterial isolates can be good candidates for detoxification of Cr(VI) in industrial effluents.     

FAHP ranking and selection of pretreatment module for membrane separation processes in textile cluster

Recent development in membrane manufacturing and extensive application of membranes in effluent treatment has opened up a new water resource. The effluent pretreatment module plays a critical role in membrane performance. Appropriate selection of conventional and advanced pretreatment modules in membrane separation processes (MSP) is significant to the success of zero effluent discharge (ZED). This study addresses performance assessment of eight conventional and advanced pretreatment modules implemented for wastewater management in a textile cluster in South India. The comparative pollutant reduction, capital, operation and maintenance (OM) cost of pretreatment modules are discussed. The ranking and interdependence of the pretreatment modules were analyzed through fuzzy analytical hierarchy process (FAHP) with MATLAB software.The pretreatment module IV ranked third with a composite weight of 15.46%. The integrated study of performance assessment and FAHP resulted in an optimum pretreatment module IV comprising the sequence of chemical precipitation, bio-oxidation processes (activated sludge processes) followed by chemical precipitation, to achieve the ZED. This study provides a techno-economically feasible solution for selection of an effective pretreatment module for MSP in the textile cluster.     

Photochemical Enzyme Immobilization on Textile Carrier Materials

The catalase (E.C. 1.11.1.6) enzyme was covalently immobilized on textile carrier fabrics made of poly(ethylene terephthalate) or polyamide 6.6 by a new photochemical process in the presence of cross‐linking agents. The enzyme and the bifunctional organic compound (diallylphthalate or cyclohexane‐1,4‐dimethanoldivinylether) were emulated in water using a non‐ionic surfactant. After wetting, the textile carrier materials were irradiated with a monochromatic excimer UV lamp (222 nm) in an inert atmosphere. Depending on the support and the cross‐linking agent used 20 – 30 mg enzyme per gram carrier could be fixed durably, which can be quantitatively analyzed by atomic absorption spectroscopy due to the iron content of the catalase. The efficiency of the immobilization products was investigated by measuring the enzymatic decomposition of hydrogen peroxide compared to the free enzyme. The relative activity of the catalase after the immobilization reached 10–20 % of the free, non‐fixed catalase. Even after 20 applications, the immobilized enzyme showed a distinct activity and the integral activity trough the period of all applications was higher by a factor of around 3.5 than the activity of the free catalase, which could be used only once in technical processes. Summing up the results, fabrics of a high protein load and a distinct activity can be produced with low preparative and economic expense by irradiating the materials by means of excimer UV lamps in the presence of cross‐linking agents.     

Phytoremediation potential of Lemna minor L. for heavy metals

Phytoremediation potential of L. minor for cadmium (Cd), copper (Cu), lead (Pb), and nickel (Ni) from two different types of effluent in raw form was evaluated in a glass house experiment using hydroponic studies for a period of 31 days. Heavy metals concentration in water and plant sample was analyzed at 3, 10, 17, 24, and 31 day. Removal efficiency, metal uptake and bio-concentration factor were also calculated. Effluents were initially analyzed for physical, chemical and microbiological parameters and results indicated that municipal effluent (ME) was highly contaminated in terms of nutrient and organic load than sewage mixed industrial effluent (SMIE). Results confirmed the accumulation of heavy metals within plant and subsequent decrease in the effluents. Removal efficiency was greater than 80% for all metals and maximum removal was observed for nickel (99%) from SMIE. Accumulation and uptake of lead in dry biomass was significantly higher than other metals. Bio-concentration factors were less than 1000 and maximum BCFs were found for copper (558) and lead (523.1) indicated that plant is a moderate accumulator of both metals. Overall, L. minor showed better performance from SMIE and was more effective in extracting lead than other metals.     

Binding of textile azo dyes byMyrothecium verrucaria

Summary A strain ofMyrothecium verrucaria that showed a high capacity for rapid decolorization of textile dye solutions was isolated from soil. As much as 70%, 86%, and 95% of Orange II, 10B (blue) and RS (red) dyes (color index no. 15510, 20470, 23635), respectively, were adsorbed from solutions of approximately 0.2 g dye per liter in 5 h by approximately 4.5 g dry weight of cells per liter of dye solution. Intact cells showed a higher adsorption capacity than disrupted cells for Orange II and RS but not for 10B. Dye bound to cells was recoverable by extraction with methanol and methanol-treated cells were able to be recycled, albeit with a slightly diminished dye-binding capacity. The Tween detergents were shown to reduce dye adsorption. Dyes strongly bound to the fungal biomass required sonication in dH₂O or in Triton X-100 or extraction with methanol for their removal. These results suggest that hydrophobic/hydrophilic interactions are important in dye binding.     

The role of ecotoxicity testing in assessing water quality

Abstract Ecotoxicology provides a basis for making decisions on the likely impact of a chemical or effluent on the aquatic environment. It encompasses laboratory ecotoxicity tests of various types to explore relationships between exposure and effect under controlled laboratory conditions, through to studies of the effects of chemicals or effluents under a variety of ecological conditions in complex field ecosystems. This paper will focus on the value of laboratory ecotoxicity tests as a tool in assessing water quality. Laboratory tests are valuable (i) in deriving and assessing water quality criteria, (ii) for screening and ranking chemicals and predicting their hazard and risk, (iii) for establishing dilution levels of chemicals or effluents prior to discharge into water bodies, (iv) in determining cause-effect relationships in post-impact studies, and (v) for establishing and validating field bioindicators. Both the advantages and deficiencies of using ecotoxicological testing for these purposes are illustrated from research with pesticides, metals and sediments. Use of a combination of both laboratory- and field-based ecotoxicology studies is important to gain a full understanding of the effects of chemicals at the ecosystem level.     

Codigestion of olive oil mill wastewaters with manure, household waste or sewage sludge

Combined anaerobic digestion of oil mill effluent(OME) together with manure, household waste (HHW) orsewage sludge was investigated. In batch experimentsit was shown that OME could be degraded into biogaswhen codigested with manure. In codigestion with HHWor sewage sludge, OME dilution with water (1:5) wasrequired in order to degrade it. Using continuouslystirred lab-scale reactors it was shown thatcodigestion of OME with manure (50:50 and 75:25 OMEto manure ratios) was successful with a theoreticalOME utilization of 75% and with approx. 87%reduction of the lipids content in OME. An OMEutilization of approx. 55%, and lipid reduction of73% was reached in codigestion with HHW (50:50 and75:25 OME to HHW ratios). The results showed thatthe high buffering capacity contained in manure,together with the content of several essentialnutrients, make it possible to degrade OME withoutprevious dilution, without addition of externalalkalinity and without addition of external nitrogensource.     

Carcinogenicity of chrysotile asbestos: A case control study of textile workers

Chrysotile is the predominant type of asbestos used in the United States and thus represents the most important source of exposure to asbestos already in place. While the steepest exposure-response observed for lung cancer has been in workers exposed to chrysotile in textile operations, some argue that chrysotile is less carcinogenic than amphibole asbestos types. Mineral oil exposures have been hypothesized to be responsible for the highly elevated lung cancer risk seen in textile workers. A lung cancer case-control analysis among a cohort of South Carolina chrysotile asbestos textile workers was conducted. Only a modest reduction in the slope of the lung cancer exposure-response relationship was observed after controlling for mineral oil exposures. These data do not support mineral oil exposure as a plausible explanation for the elevated lung cancer risk seen in chrysotile asbestos textile workers. The possible role of longer, thinner, more carcinogenic fibers in textiles is one plausible hypothesis needing further investigation.