Avaliação da auto-suficiência energética de reatores anaeróbios no tratamento de esgoto sanitário e água cinza

The anaerobic treatment of sewage is widely employed in Brazil and it is an appreciated way for the treatment of effluents, helping to reduce the environmental impact in rivers. The methane gas obtained from the process can be applied to improve the energetic efficiency of the system, reducing the amount of waste and the cost of the treatment process. This work presents the net energy balance of anaerobic reactors applied to the treatment of sewage. The analysis was performed considering full-scale and laboratory-scale treatment systems. In laboratory scale, the results from three kinds of systems were compared regarding the biological treatment of greywater. Two of them (UASB7 and UASB12) were anaerobic and the other one was a combined anaerobic-aerobic system (UASB7/SBR6). Greywater methanization (compared to theoretical maximum) was calculated considering 100% removal (g BOD/day), the literature percentage removal and the anionic surfactant presence in the effluentt. For each of these three cases, the efficiencies were, respectively, 16.9%, 43.6% and 51.3% in UASB7 reactor, 25.6%, 50.3% and 59.2% in UASB12 reactor and 30.6%, 61.2% and 71.9% in UASB7/SBR6 reactor. The energetic potential was found to be 4.66x10-4, 7.77x10-4 and 5.12x10-4 kWh/L for the UASB7, UASB12 and UASB7/SBR6 reactors, respectively. The pumping system, the aeration (in the anaerobic-aerobic system) and the temperature controlled heating system were considered to calculate the energetic consumption. However, the third one was not employed since tropical regions like Brazil do not need heating systems and also because of its high energetic consumption. The calculated net energy balance in the reactors was negative in the case of greywater, respectively -0.16, -0.28 and -0.18 kWh/L for the reactors UASB7, UASB12 and UASB7/SRB6. In full scale (ETE Jardim das Flores - Rio Claro, SP), the average energy... (Complete abstract click electronic access below)

Projeto de um sistema anaeróbico para estabilização de lodo e recuperação de energia

The treatment of domestic and industrial effluents through Wastewater Treatment Plants (WTPs) generates a residue termed sewage sludge, rich in organic matter, high-volume, occasionally containing pathogens and heavy metals. The sludge generation can minimize the benefits brought by the treatment of sewage, because this residue does not always receive appropriate treatment before final disposal. The disposal is another problem related to sludge. Landfills generally does not have physical space and alternatives such as the use in agriculture requires an intense treatment that could be in many cases operational or economic unfeasible. The objective of this work is the theoretical research about the processes of stabilization of the sludge by anaerobic digestion and the methanogenic activity during the process. Through analysis of each step and contemplating each relevant factor in anaerobic digestion process in order to optimize them, we proposed a theoretical model of reactors capable of stabilize the sludge, reduce its volume and eliminate pathogens. The obtained configuration consists of two anaerobic reactors connected in series. The first one operates in the range mesophilic temperature (35 ° C) and has higher hydraulic retention time (25 days) working primarily in the stabilization of organic matter present in the sludge and producing biogas, whereas the second one operates in the thermophilic range (55 ° C) in order to eliminate pathogens, and to reduce the volume. The hydraulic retention time in the second reactor is lower (10 days). Both mesophilic and thermophilic processes were efficient in what was proposed, promoting the stabilization of organic matter present in the sludge and significant reduction of pathogens. As a final step with the sludge previously digested, it is indicated a final dehydration... (Complete abstract click electronic access below)

Aproveitamento energético de resíduos de esgotamento sanitário

This paper presents alternatives for waste energy recovery from the sewage of cities. Through a review of the literature it is observed that the technologies studied are usually turbines, microturbines, and engines adapted to the use of biogas. For project design analyzes the technologies found in some sewage treatment plants in Brazil and the world, compared with those found in the literature. With this study it can be concluded that the most used technologies are microturbines and motor generator sets, which are already implemented in some locations in the USA, Europe and even Brazil. It can also be concluded that the energy recovery of waste from sewage can enable design of wastewater treatment plants thereby contributing to improved quality of life

Degradação ambiental e qualidade de vida na microbacia do Córrego do Gramado – Presidente Prudente/São Paulo

The late industrialization, together with other factors, ended up directing much of the rural population to cities, without adequate planning, resulting in high density and irregular settlements in risk areas to low-income population. The man settled in the urban site to break environmental laws that eventually causing an imbalance in the natural environment, causing or exacerbating the shortage in availability of water resources. This situation also happened in Presidente Prudente, especially in the east, the focus of this research. Therefore, this study aims to understand the causes of degradation of waterways in urban areas, focusing on society's relationship with nature and its consequences on environmental quality and quality of life of urban population located in the watershed of stream of Gramado, Presidente Prudente - São Paulo. In this catchment there is the irregular deposition of solid waste in the valley, remnants of old pollution release of domestic sewage and industrial (currently collected and intended for treatment), accelerated processes of erosion in some areas of intensive use of the relief and consequently, the bed siltation of streams that are part of the basin. The quality of urban life was seen through socioeconomic and environmental indicators, which were identified through questionnaires to residents, according to local residence in the landscape, divided into three segments: the tops 60 residents, 90 residents and 112 residents in the areas in valley bottoms. With these data we can relate them to the degradation of the basin and aggregate them to the quality of life of residents. Field studies were needed to visualize the changes that occurred in the watershed over the past three years, with the implementation of works aimed at improvements to the community as the conduit stream of Gramado and construction and operation of Sewage Pumping Stations... (Complete abstract click electronic access below)

Análise morfológica de brânquias de peixes Oreochromis niloticus (tilápia) expostos ao níquel

Water is an essential factor in maintaining the vital functions of living beings. We have observed a growing commitment of quality, are due to pollution from many sources and even entire watersheds, whether for industrial waste, sewage, or for substances used in farming such as pesticides, herbicides and fertilizers. Nickel is the 24th most abundant element on earth, is a heavy metal that, in the form of chloride, is a proven genotoxic and mutagenic. Due to its industrial use, there was considerable increase of its concentration in surface sediments. Fish combine characteristics that make them excellent experimental models for aquatic toxicology studies, which are particularly usable as warn about the potential danger of chemicals or the possibility of environmental pollution. Due to impaired water quality and the few published studies relating the nickel with the tissue change, this study aimed at assessing the consequences of the presence of nickel in the aquatic environment. For this analysis, we used individuals of Oreochromis niloticus, exposed for 96 hours at three different concentrations of nickel dissolved in water compared to a control group. After exposure, the gills were removed and these were analyzed by ultramorphological, histological and histochemical analysis. The results indicate that all concentrations used in the experiment altered the histophysiology of exposed individuals. We observed the following changes: rupture of paviment cells, thus resulting in bleeding, loss of microridges surface of these cells and epithelial loss in the gills of all animals in all treatments with nickel chloride, the histochemical analysis showed non-proliferation of chloride cells. However, there was a dose-dependent increase of mucus cells in all animals. Therefore, nickel has toxic potential to fish, from the smallest concentration used up to twice as permitted by law, indicating... (Complete abstract click electronic access below)

Resolução de problema de valor no contorno associado ao projeto de reatores de fluxo disperso empregados no tratamento de efluentes

The objective of this work was to develop a numerical method to solve boundary value problems concerning to the use of dispersion model for describing the hydraulic behavior of chemical or biological reactors employed in the wastewater treatment. The numerical method was implemented in FORTRAN language generating a computational program which was applied to solve cases involving reaction kinetics of both integer and fractional orders. The developed method was able to solve the proposed problems evidencing to be a useful tool that provides more accurate design of wastewater treatment reactors

Propostas de Adequação Ambiental para a Cidade da Criança de Presidente Prudente - SP

The environmental issue has been considered of fundamental importance for the well being of the present and future generations and is inserted into the commitment of political parties at federal, state and municipal government programs, into the interests of popular organizations and business planning. The Parque Ecológico Cidade da Criança is one of the most sought after places for visitation at Presidente Prudente – SP. Located outside the Raposo Tavares Highway, next to the exhibition grounds and beside the agricultural school, has more than 30 acres of area with an infrastructure designed for recreation and leisure activities for all ages and has received new investment of the public power. Given the importance of the ecological aspects, the objective of this work is to perform an environmental diagnosis in order to be able to submit proposals for solving the problems encountered and improve the use of the environmental resources. Therefore, the study was divided into three foci: sewage disposal, erosion process and control of the stormwater drainage system. It was checked the discharge of sewage from the restaurant on exposed soil, erosion processes that develop at the camel and llama cages ground and erosion processes resulting from the convergence of the stormwater in the highest region of the park. Based on these studies, proposals of solution were made for each case, having considered the effectiveness of the project

Estudo sobre a condição de coleta e tratamento de esgoto sanitário do município de Ubatuba-SP

The actual work broaches a study about the collection and treatment of sanitary sewage from the municipality of Ubatuba in its operational aspects and the tariff policy from the service. Themes related to the subject like the history of collection and treatment of sewage, its development in Brazil and its importance for public health and environmental preservation, as well as historical and geographical aspects of Ubatuba/SP, are present in the literature review. The methodology consists in guided visit in the colletion and treatment of sewage facilities and interview with technical managers. With the technical data obtained, it is made a discussion of the results and possible recommendations

Estudo da qualidade da água do Ribeirão Guaratinguetá

This paper conducts to water quality study of Stream Guaratinguetá from its source to its confluence with the River Paraiba, through the analysis of some physical, chemical and biological parameters. All tests were performed according to Standard Methods for Examination of Water and Wastewater 20th edition and compared to the CONAMA Resolution No. 357 (2005). Coliforms was the most critical parameter found in samples. The results lead to the conclusion that the biggest problem of water quality in the stream in study is the aquatic rice (rice field) and the launch “fresh” sewage

Variação espacial e temporal da qualidade da água de três córregos tributários do Rio Bauru: respostas ao processo de recuperação de nascentes

Este trabalho objetivou analisar a qualidade da água de três córregos tributários do rio Bauru, levando em conta a poluição causada por produtos orgânicos e industriais que vinham sendo descartados nos mesmos e as eventuais melhorias conseqüentes das medidas paliativas assumidas pelo DAE-Bauru, mediante a instalação de interceptores-coletores de águas residuárias ao longo Daqueles corpos de água, até que a Estação de Tratamento de Esgotos do município seja construída e se dê início ao seu funcionamento. O monitoramento destes corpos de água durante o período de estiagem e de cheias proposto nesta pesquisa, incluiu investigações sobre as variáveis químicas e físicas de amostras das águas, obtidas mensalmente em 7 pontos de coleta, localizados a montante e a jusante dos pontos de instalação dos emissários, ao longo dos córregos. As amostras de água foram posteriormente analisadas para fossem obtidas informações sobre a eficácia da instalação dos interceptores com relação ao processo de recuperação da saúde dos corpos aquáticos em questão. Os resultados obtidos mostraram que, de um modo geral, as águas de todos os sistemas estudados ainda sofrem impactos, até porque ainda há aquelas que recebem o esgoto descartado “in natura”. No entanto, como ja era esperado, nos pontos de coleta localizados em segmentos dos córregos nos quais os emissários já foram instalados, o impacto ambiental é menor. Mediante a comparação dos resultados obtidos das análises das características físicas e químicas das águas dos sistemas estudados realizadas durante esta investigação com aqueles obtidos nos mesmos corpos de água, em 2007, pudemos observar melhorias da água em alguns dos pontos de coleta

Comparação de eficiências do uso de sistemas construídos de áreas alagadas (Constructed Wetland Systems - CWS), tipos ascendente e descendente, para tratamento de efluentes

Water is an essential element for life. The use of this element, to support the community, defines it as water resource. This feature is being misused and degraded by the dumping of highly contaminated effluents. The impoverishment of its quality poses a risk to human consumption. The necessity to manage this resource, treating the wastewater properly, requires the constant improvement of treatment systems. Another need is to adjust the cost of systems to the demands of communities with less financial clout. This study aimed to adapt and understand the systems of wetlands, improving its efficiency, in an attempt to collaborate with the enrichment of this technology. The practical evidence, with lab-scale prototypes, assembled in ETE Piracicamirim with urban sewage effluent contributed to highlight the problems and operating system design. The bibliographic review showed that several studies had effectiveness for treatment. But it was evident the need for better understanding of dimensioning definitions that better attempted to the answers into the project. Moreover, standardization of system conditions for the specific wastewater treatment is an interesting field, identified, for future studies yet contribute to environmental engineering and sanitation

Avaliação da auto-suficiência energética de reatores anaeróbios no tratamento de esgoto sanitário e de água preta

The purpose of this project is to verify whether anaerobic reactors applied to sewage treatment are energetically self-sufficient. This evaluation can be made by balancing the methane produced through the anaerobic transformation stages (hydrolysis, acidogenesis, acetogenesis and methanogenesis) and the reactor energy consumption requirements. The original project included methanogenic activity tests, which could not be performed due to setbacks in the installation of an analytical instrument. Scientific articles about bench- and full-scale anaerobic reactors were investigated instead. An average substrate-to-methane conversion efficiency of 58,2±18,6% was found for the bench-scale reactors and higher efficiencies (89,2%) were found for the cases which had higher Organic Loading Rates (OLRs) values. The average energy output was 0,013 kWh/Lsewage, value unable to meet the energy needs for the reactor operation, considering equipments normally used such as temperature controller. This balance can become positive if few hypotheses are made, for example (i) to eliminate the use of temperature controller (ii) to alter the operation pattern from continuous to intermittent. Based on energy balance assessment of eight bench-scale reactors, it was observed that the implementation of a system for biogas utilization is not energetically feasible. However, interesting results were found for a full-scale sewage treatment plant, ETE Ouro Verde – Foz do Iguaçu, PR, Brazil. Even though its substrate-tomethane conversion efficiency was about 10% only, the energy balance was quite positive, with energy consumption of 68 kWh/month and energy production of 660 kWh/month. This analysis leads us to conclude that energy recovery from full-scale sewage treatment plants should be practiced by other plants

Prevalência das enteroparasitoses em escolares após Programa de Saneamento Ambiental (Bahia Azul) realizado em Salvador, BA

Introduction: The intestinal parasites continue to represent a significant public health problem, due to the large number of infected people and the various organic changes that can cause. The intestinal parasites become more prevalent in villages with high population density absence or inadequacy of sanitation and adequate, and personal hygiene practices and inadequate housing. Objective: To determine the prevalence of intestinal parasites Ascaris lumbricoides, Trichuris trichiura and Giardia duodenalis in children of school age (7-14 years) living in the city of Salvador, Bahia, which were part of the Environmental Sanitation Program (Bahia Azul) covering eight different sewage basins in the years 1997/1998 and 2003/2004. Methods: Data were collected pre-coded questionnaire administered to the parents of students, collecting information socioeconomic, environmental and housing conditions. Stool samples were analyzed for each school in the Laboratory of Parasitology of the ISC, UFBA. The database was built and analyzed by Epi Info program (version 3.5.1/2008) were built where overall prevalence rate and Basin depletion of parasites. We compared the overall prevalence rates (at least one parasite) before and after the intervention health, as well as species of parasite. Results: The overall prevalence before the intervention was 56,2% (N = 729) and 42,5% after the intervention (N = 890), down -24,5%. The prevalence observed for each species A. lumbricoides, T. trichiura and G. duodenalis before intervention was respectively 31,4%, 35,8% and 9,9% respectively after the intervention and 24,4%, 28,8% and 6,0%. In relation to variations in prevalence were found to decrease A. lumbricoides, T. Trichiura and G. duodenalis respectively -22,4%, -19,7% and -39,7%. When the results were compared by Basin exhaustion, it was observed that the greatest variation with reduction occurred among students Basin M. Camurujipe to at least one parasite (-51,4%), ...

Planejamento ambiental da bacia hidrográfica do córrego Embirí – UGRHI Pontal do Paranapanema – São Paulo: inventário e diagnóstico

This study aimed to contribute to the environmental planning of the watershed Embirí stream - UGRHI Pontal Paranapanema (belonging to the Paranapanema Management unit) in the cities of Presidente Prudente and Regente Feijó, São Paulo. This basin is located in the area of the Santo Anastácio river source, responsible for supplying water to about 30% of the population of Presidente Prudente. The methodological procedures based on Leal (1995) and Rodriguez et al. (2004), and the steps include inventory and diagnosis of the basin. We conducted extensive literature review, cartographic and documentary on the subject area of research, field work, preparation of thematic maps and summary chart of physical units and environmental use and land cover, participatory mapping of environmental risks, quality analysis of water. Most of the basin of the stream of twine had a high environmental fragility and the main problems found were lack of riparian vegetation, erosion, siltation of water bodies, irregular disposal of debris and the dumping of sewage. The results were summarized in the diagnosis and can identify the most important environmental impacts, environmental and spatial weaknesses of the legislation, and thus draw up proposals for action to the area that is substantially degraded

Avaliação da atenuação da toxicidade de lodo de esgoto por associação com resíduo vegetal da indústria sucro-alcooleira

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)