Rational use of residential digesters for sewage treatment with Carbon Credits

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The competitive challenge for Brazilian industry

Includes bibliography

The North-South dimension of the environmental and cleaner technology industries

Includes bibliography

The ideas of young Prebisch

Includes bibliography

A proposal for unitary taxes on the profits of transnational corporations

Includes bibliography

Caracterização geofísica em aterro de resíduos sólidos para avaliação de condicionantes de instabilidade geotécnica

The disposal of solid waste can create environmental problems, in addition to the potential risk of instability even in planned geotechnical works, such as provisions in stacks or high ends of the landfill, because they represent mere adjustments in civil engineering works. The Leme city, SP, generates about 35 t/day of municipal waste, that are deposited in a landfill located in the Barro Preto neighborhood. This work conducted a geophysical survey, based on geotechnical instability evidence in area, for analysis of the conditioners that cause on the sides leachate resurgence landfill and its relationship to mass movements and ravines installation in cover soil, with consequent waste exposure. The results indicate horizons of low resistivity connected with resurgence points generated by the organic matter decomposition contained in the waste. Such horizons result in leachate concentration in some places, which, in turn, may lead to loss of cohesion of the materials constituting the residues mass. The results are areas with mass flow by rotational movements, which, together with the surface flow of rainwater, evolves into ravines and exposed residues, preferably at the resurgence point. The leachate flow on the surface affects areas beyond the limits at landfill with direct impact on local agriculture and risk to pedestrians using the highway bordered by the landfill beyond the soil and the local aquifer.

Assessment of the genotoxicity of two agricultural residues after processing by diplopods using the Allium cepa assay

Agroindustrial by-products and residues from treatment of sewage sludge have been recently recycled as soil amendments. This study was aimed at assessing toxic potential of biosolid, obtained from a sewage treatment plant (STP), vinasse, a by-product of the sugar cane industry, and a combination of both residues using Allium cepa assay. Bioprocessing of these samples by a terrestrial invertebrate (diplopod Rhinocricus padbergi) was also examined. Bioassay assembly followed standards of the Brazilian legislation for disposal of these residues. After adding residues, 20 diplopods were placed in each terrarium, where they remained for 30 days. Chemical analysis and the A. cepa assay were conducted before and after bioprocessing by diplopods. At the end of the bioassay, there was a decrease in arsenic and mercury. For the remaining metals, accumulation and/or bioavailability varied in all samples but suggested bioprocessing by animals. The A. cepa test revealed genotoxic effects characterized by different chromosome aberrations. Micronuclei and chromosome breaks on meristematic cells and F1 cells with micronuclei were examined to assess mutagenicity of samples. After 30 days, the genotoxic effects were significantly reduced in the soil + biosolid and soil + biosolid + vinasse groups as well as the mutagenic effects in the soil + biosolid + vinasse group. Similar to vermicomposting, bioprocessing of residues by diplopods can be a feasible alternative and used prior to application in crops to improve degraded soils and/or city dumps. Based on our findings, further studies are needed to adequately dispose of these residues in the environment. © 2013 Springer Science+Business Media Dordrecht.

Concentrations of Cu, Fe, Mn, and Zn in tropical soils amended with sewage sludge and composted sewage sludge

Sewage sludge may be used as an agricultural fertilizer, but the practice has been criticized because sludge may contain trace elements and pathogens. The aim of this study was to compare the effectiveness of total and pseudototal extractants of Cu, Fe, Mn, and Zn, and to compare the results with the bioavailable concentrations of these elements to maize and sugarcane in a soil that was amended with sewage sludge for 13 consecutive years and in a separate soil that was amended a single time with sewage sludge and composted sewage sludge. The 13-year amendment experiment involved 3 rates of sludge (5, 10, and 20 t ha-1). The one-time amendment experiment involved treatments reflecting 50, 100, and 200 % of values stipulated by current legislation. The metal concentrations extracted by aqua regia (AR) were more similar to those obtained by Environmental Protection Agency (EPA) 3052 than to those obtained by EPA3051, and the strongest correlation was observed between pseudo(total) concentrations extracted by AR and EPA3052 and bioavailable concentrations obtained by Mehlich III. An effect of sewage sludge amendment on the concentrations of heavy metals was only observed in samples from the 13-year experiment. © 2012 Springer Science+Business Media B.V.

Efeito do lodo de esgoto e do nitrogênio nos fatores produtivos do girassol

In Brazil, among the various alternatives for final disposal of sewage sludge, agricultural use is notable for its economy and environmental compatibility. The objective of this study was to evaluate the effect of composted sewage sludge and N parameters on sunflower production after the sixth application of sewage sludge in different doses. The experiment was conducted at the Experimental Farm São Manuel-SP, belonging to the Faculty of Agronomic Sciences, UNESP, Botucatu-SP. The experimental design adopted was randomized blocks, consisting of six treatments and four replications defined as follows: T0 - without nitrogen fertilization; T1 - chemical nitrogen fertilizer in accordance with the recommendation for the crop; T2 - 50% nitrogen derived from sewage sludge and 50% in mineral form; T3 - 100% nitrogen from sewage sludge; T4 - 150% nitrogen from sewage sludge; T5 - 200% nitrogen from sewage sludge. Increasing the dose of sewage sludge and N provided an increase in grain yield, oil and dry matter. The N influenced the increase in the weight of thousand grans.

Efeito do manejo e de níveis de lodo de esgoto na fertilidade do solo após tres aplicações

The agricultural use of sewage sludge as organic fertilizer is considered nowadays as on alternative of disposal, in the end of the residue in addition to possible environmental problems, it's using can decrease the mineral fertilizers and avoid provide organic matter to the soil. The objective of this study it was to evaluate the parameters of soil fertility under different managements and doses of sewage sludge after the third application of the residue. The experiment was carried out in São Manuel - SP, with the cultivation of sunflower in two consecutives cycles, followed by wheat and triticale without application of the residual, and in the following year with the application of sewage sludge and cultivated the black oats. It was adopted a randomized complete block design, consisting of six treatments and five repetitions defined as follows: T0 - without fertilization; T1 - mineral fertilizer nitrogen according to crop need, T2 - 50% of N from sewage sludge and 50% in mineral form, T3 - 100% of N from sewage sludge, T4 - 150% of N from sewage sludge, T5 - 200% of N derived from sewage sludge. Soil samples were collected in the end of the trial of oats. There were an increase in the levels of P, H + Al, CEC and OM, B, Cu, Fe, Mn, Zn as a function of increasing dose of sewage sludge. To V% and pH were decreased the values in the proportional soil to the increase of sludge dose until 24 and 22 t ha-1, respectively and after increasing the pH and V%.

Evaluation of metals in water and sediments of micro-basins in the city of Americana, São Paulo state, Brazil

Water pollution found in major rivers in Brazil has its origin from urban sewage discharges and industrial effluent, carried out by small streams and rivers crossing cities. Therefore, studies related to hydrographic micro-basins offer the opportunity to establish environmental management strategies for restoring water resources, based on diagnosis of the water quality. Despite this understanding, few studies in urban and rural areas have been performed in a systematic manner in Brazilian micro-basins. The main goal of this research was to diagnose the water resources in micro-basins in the region of the district of Americana, São Paulo state, Brazil, through the quantification of metals in water and sediment. The methodology was based on the investigation of metals (Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn), in four micro-basins, determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The most significant result showed high concentration levels of chromium (969 μg L-1), downstream of the discharge of sewage from the city of Nova Odessa. This concentration in the river was above the allowed limit of Brazilian regulation agency (50 μg L-1 for Cr). Also high levels of Cr were found in the sediment (98.9 μg g-1) collected at the same monitored site. These results are important indicators of environmental performance and anthropogenic activities to help the government establish environmental management strategies aimed at the reduction of water pollution. © 2013 WIT Press.

Sintering of porous alumina obtained by biotemplate fibers for low thermal conductivity applications

In this research report, a sintering process of porous ceramic materials based on Al2O3 was employed using a method where a cation precursor solution is embedded in an organic fibrous cotton matrix. For porous green bodies, the precursor solution and cotton were annealed at temperatures in the range of 100-1600°C using scanning electron microscopy (SEM) and thermogravimetric (TG) analysis to obtain a porous body formation and disposal process containing organic fibers and precursor solution. In a structure consisting of open pores and interconnected nanometric grains, despite the low porosity of around 40% (calculated geometrically), nitrogen physisorption determined a specific surface area of 14m2/g, which shows much sintering of porous bodies. Energy dispersive X-ray (EDX) and X-ray diffraction (XRD) analytical methods revealed a predominant amount of α-Al2O3 in the sintered samples. Thermal properties of the sintered Al2O3 fibers were obtained by using the Laser Flash which resulted in the lower thermal conductivity obtained by α-Al2O3 and therefore improved its potential use as an insulating material. © 2012 Elsevier Ltd.

Analysis of hybrid waste-to-energy for medium-sized cities

Urban centers have a huge demand for electricity and the growing problem of the solid waste management generated by their population, a relevant social and administrative problem. The correct disposal of the municipal solid waste (MSW) generated in cities is one of the most complex engineering problems that involves logistics, safety, environmental and energetic aspects for its adequate management. Due to a national policy of solid wastes recently promulgated, Brazilian cities are evaluating the technical and economic feasibility of incinerating the non-recyclable waste. São José dos Campos, a São Paulo State industrialized city, is considering the composting of organic waste for biogas production and mass incineration of non-recyclable waste. This paper presents a waste-to-energy system based on the integration of gas turbines to a MSW incinerator for producing thermal and electric energy as an alternative solution for the solid waste disposal in São José dos Campos, SP. A technical and economic feasibility study for the hybrid combined cycle plant is presented and revealed to be attractive when carbon credit and waste tax are included in the project income. © 2013 Elsevier Ltd.

Potentially hazardous waste produced at home

Background: The purpose of this study was to identify the sources of waste generation household consisting of biological material and to investigate the knowledge presented by those responsible for the generation of waste in the home environment on the potential health risk human and environmental. Method. It is a quantitative survey performed in Parque Capuava, Santo André (SP). The questionnaire was administered by the community employers and nursing students during the consultation with nursing supervision through interview question/answer. The exclusion criteria were patients who were not in the area served by the Basic Health Unit which covers the area of Pq Capuava. The sample was consisted of 99 persons and the data collection a questionnaire was used. Results: We observed that 63.3% of people said to use disposables, with the majority (58.7%) of these use the public collection as the final destination of these materials. It was reported that 73.7% of those surveyed reported having knowledge about the risk of disease transmission. Public awareness of the importance of proper packaging and disposal of potentially hazardous household waste may contribute significantly to the preservation of human and environmental health and this procedure can be performed and supervised by professional nurses. Conclusion: We suggest implementation of workshops for community health workers and the general population in order to enhance their knowledge about the storage and disposal of potentially infectious waste generated at home, thereby reducing the potential risk of disease transmission by improper management. © 2013 Chaves et al.; licensee BioMed Central Ltd.

PLA and Organoclays Nanocomposites: Degradation Process and Evaluation of ecotoxicity Using Allium cepa as Test Organism

In this study, nanocomposites of PLA and organoclays Cloisite 20A and Cloisite 30B were prepared by the melt intercalation method and the obtained samples were characterized by transmission electron microscopy (TEM). Since composting is an important proposal to the final disposal of biopolymers, the influence of clays on the hydrolytic degradation process of PLA was evaluated by visual analysis and monitoring of molecular weight after periods of 15 and 30 days of degradation in compost. After degradation of the materials in composting environment, the evaluation of cytotoxic, genotoxic and mutagenic effects of compost aqueous extract was carried out using a bioassay with Allium cepa as test organism. The TEM micrographs permitted the observation of different levels of dispersion, including exfoliated regions. In the evaluation of hydrolytic degradation it was noted that the presence of organoclays can decrease the rate of degradation possibly due to the barrier effect of clay layers and/or the higher degree of crystallinity in the nanocomposite samples. Nevertheless, even in the case of nanocomposites, the molecular weight reduction was significant, indicating that the composting process is favorable to the chain scission of PLA in studied materials. In the analysis performed by the bioassay using A. cepa as test organism, it was found that after degradation of the PLA and its nanocomposites the aqueous extract of compost samples induced a decreasing in the mitotic index and an increasing in the induction of chromosomal abnormalities. These results were statistically significant in relation to the negative control (distilled water). By comparing the results obtained for the nanocomposites in relative to pure polymer, there were no statistically significant differences. The types of the observed chromosomal aberrations indicated a possible genotoxic effect of the materials, which may be related to an aneugenic action of PLA degradation products. © 2013 Springer Science+Business Media New York.