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Sequential Anaerobic-Aerobic Digestion: A new process technology for biosolids product quality improvementKumar, Nitin 11 May 2006 (has links)
Anaerobic digestion is widely used for stabilization of solids in sewage sludges. Recent changes in the priorities and goals of digestion processes are focusing more attention on the efficiency of these processes. Increasing hauling cost and restrictions for land applications are two factors which are driving the increased attention to digestion efficiency. Noxious odor production from the land applied biosolids is another important issue related to digestion efficiency. Existing anaerobic digestion or aerobic digestion processes failed to provide simultaneous solution to biosolids related problems i.e. simultaneous VS reduction, better dewatering of biosolids and lesser odors from the biosolids.
Studies done by Novak et al. (2004) using different activated sludges show that anaerobic-aerobic digestion and aerobic-anaerobic digestion both increase volatile solids reduction compared to a single digestion environment. They proposed that there are 4 VS fractions in sludges: (1) a fraction degradable only under aerobic conditions, (2) a fraction degradable only under anaerobic conditions, (3) a fraction degradable under both anaerobic and aerobic conditions, and (4) a non degradable fraction. It has also been found (Akunna et al., 1993) that anaerobic-aerobic sequential treatment of wastewater can help in achieving substantial nitrogen removal. These results suggest that sequential anaerobic-aerobic digestion can address multiple biosolid related problems.
This study was designed to understand the effect of sequential anaerobic-aerobic digestion on the properties of resulting effluent biosolids. The study was carried out in two operation phases and during both phases one digester was maintained at thermophilic conditions and the other at mesophilic temperature conditions. In first operation phase (Phase-I) thermophilic digester was operating at 20 day SRT and mesophilic anaerobic digester was at 10 day SRT. The aerobic digesters following anaerobic digesters were operating at 6 day SRT. In second operation phase (Phase-II), both thermophilic and mesophilic anaerobic digesters were operating at 15 day SRT and both had two aerobic digesters operating in parallel at 3 day and 6 day SRTs.
In addition, batch experiments were also conducted to measure the performance of aerobic-anaerobic digestion sequence. Another study was carried out to understand the nitrogen removal mechanism during aerobic digestion of anaerobic digested sludge. The feed sludge was spiked with four different concentrations of nitrate and nitrite.
It was observed during the study that aerobic digestion of anaerobic sludge helps in achieving higher Volatile solid reduction (~65% vs ~ 46% for mesophilic digestion and ~52% for thermophilic digestion). This result supports the hypothesis concerning the different fractions in volatile solids. Experimental results also show that the increase in VSR upon increasing anaerobic digestion SRT (more than 15 days) is less than the increase in the VSR due to the same increment of aerobic digestion SRT. Reduction in COD and VFA were also measured to be more than 50% during aerobic digestion.
Investigation of nitrogen fate during the sequential anaerobic-aerobic digestion show more than 50% total nitrogen removal. Higher nitrogen removal was in thermophilic anaerobic – aerobic digester combination than that in mesophilic anaerobic–aerobic combination. The most probable reason for the removal was simultaneous nitrification and denitrification. Higher concentration of readily available VFA from thermophilic anaerobic digested sludge provide advantage in denitrification in following aerobic digester.
The resulting biosolids produced during sequential digestion process were also analyzed for dewatering properties and odor production. Proteins and polysaccharides concentrations were observed to decrease during aerobic digestion for thermophilic anaerobic - aerobic digestion combination, while in another combinations polysaccharide concentrations increases at aerobic phase with 3 day digestion. The concentration of polysaccharides decreases at higher digestion period of 6 and 9. The result of decrease in polysaccharide and protein was reflected by the reduction in the polymer dose consumption and decrease in the optimum CST for the biosolids resulting from the sequential anaerobic aerobic digestion.
Experimental results from odor experiments show that odor production potential of the biosolids decreases with increase in both anaerobic phase SRT and aerobic phase SRT. Thermophilic biosolids produces comparatively low odors but for longer periods, while mesophilic biosolids produces higher magnitude of odors during storage but only for comparative shorter period. Aerobic digestion of anaerobic sludge helps in reducing more than 50% odor production, but freeze-thaw cycle experiment shows that in both anaerobic and sequential anaerobic – aerobic digested sludges have higher potential for odor production. Higher aerobic digestion SRTs (6 days and above) shows more potential of reducing odors, but more experimental work is required to be done. / Master of Science
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Developing an integrated concept for sewage sludge treatment and disposal from municipal wastewater treatment systems in (peri-)urban areas in Vietnam / Entwicklung eines ganzheitlichen Konzeptes zur Behandlung und Entsorgung von Klärschlamm aus kommunalen Abwasserbehandlungsanlagen in (peri-)urbanen Gebieten VietnamsKarius, Ralf 23 August 2011 (has links) (PDF)
The study took place in Vietnam at Hanoi University of Science in the framework of the DAAD (German Academic Exchange Service) – “An advancement of the German-Vietnamese University partnerships”. The research has been supported by the program: “Wastewater and Solid Waste Management in Provincial Centers” and belongs to its technical component.
The present diploma thesis elaborates the current situation of sewage sludge management in Vietnam and is dealing with sludge characteristics from both domestic sewage treatment facilities and septic tanks. During the research, different treatment components and treatment facilities have been analyzed to carry out a comprehensive survey of sewage sludge types. In this thesis, a guideline (draft) was developed as a main result, which can be helpful to bridge the legislative gap for sewage sludge re-use in Vietnam.
In conclusion, an integrated concept has been developed, which recommends the application of selected proceeding elements to treat sewage sludge and the further utilization of re-useable materials in agriculture in a controlled and environmentally-safe manner. / Die Diplomarbeit wurde im Rahmen des Deutsch-Vietnamesischem Auslandsaustauschprogramms an der „Hanoi University of Science“ verfasst. Dieses Vorhaben wurde unterstützt von dem DAAD (Deutschen Akademischen Austausch Dienst), und ist im technischem Bereich des Programms “Wastewater and Solid Waste Management in Provincial Centers“ einzugliedern.
Die vorstehende Diplomarbeit beschäftigt sich mit dem aktuellen Klärschlammmanagement in Vietnam und liefert dabei detaillierte Resultate zu verschiedenen Klarschlammtypen aus kommunalen Abwasserbehandlungsanlagen. Bei den Untersuchungen wurden verschiedene Abwasser- und Klärschlammbehandlungsanlagen untersucht, um einen Überblick zu den gebräuchlichen Behandlungsmethoden in Vietnam zu erarbeiten. Zusätzlich wurden die institutionellen und rechtlichen Rahmenbedingungen überprüft. Der Entwurf einer Verordnung zur Verwertung von Klärschlamm in der Landwirtschaft wurde vorgelegt, um eine bestehende rechtliche Lücke in Vietnam zu schließen.
Mit dieser Arbeit wurde ein integriertes Konzept entwickelt, welches mittels verschiedene verfahrenstechnische Elemente den Klärschlamm behandelt und darauffolgend das verwertbare Material in ausgewählten landwirtschaftlichen Flächen in einer kontrollierten und umweltschonenden Weise verwertet.
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Avaliação do potencial do lodo oriundo de fossas/tanques sépticos domiciliares da Região Metropolitana de Cuiabá (RMC) para disposição final em solo agrícolaSilva, Joab Almeida da 04 November 2014 (has links)
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Previous issue date: 2014-11-04 / O lodo de esgoto é um resíduo perigoso de acordo com a NBR 10.004/04, e quando mal gerenciado, pode afetar de modo adverso não apenas o meio ambiente como a saúde pública, por ser agente de propagação de doenças. Por outro lado, o biossólido obtido a partir do lodo de esgoto doméstico é considerado um ótimo biofertilizante devido à sua composição, por ser rico em matéria orgânica, nitrogênio e fósforo. Este trabalho teve como objetivo avaliar o potencial do lodo oriundo de fossas/tanques sépticos domiciliares da Região Metropolitana de Cuiabá (RMC) para disposição final em solos agrícolas. O experimento de leito de secagem natural foi desenvolvido em um laboratório terceirizado com o objetivo de avaliar a qualidade do lodo coletado em fossas sépticas dos bairros Dom Aquino, Coxipó da Ponte, Morada da Serra, Boa Esperança e Jardim Universitário e lodo transportado por veículos limpa-fossa. O experimento seguiu o mesmo procedimento de tratamento do lodo nas estações de tratamento de esgoto. Após esse processo, o material foi higienizado com cal virgem a 50% da base seca e submetido a um período de maturação de 30 dias, posteriormente foram submetidas a análises laboratoriais. Os parâmetros analisados foram com relação à estabilidade, a metais pesados e organismos patogênicos resistentes. Os resultados foram comparados com os padrões da legislação vigente. Também foram utilizadas técnicas de geoprocessamento e sistemas de informações geográficas (SIG) com objetivo de identificar as áreas potencialmente aptas para recebimento de biossólido. De acordo com os resultados obtidos, o leito de secagem de exposição natural apresentou eficiência na desidratação e estabilização do lodo, atingindo níveis menores que 10% de umidade e a relação entre sólidos voláteis e totais menores que 0,10; com relação às concentrações de elementos-traços de metais analisadas, todas as amostras de biossólidos apresentaram teores inferiores aos valores máximos permitidos pela Resolução CONAMA 375/06, inclusive a amostra do caminhão limpa-fossa, que apresentou os teores mais elevados dos parâmetros analisados; após a higienização do lodo, o material apresentou qualidade de biossólido classe A em relação à concentração de organismos patogênicos; por fim, o estudo do meio físico viabilizou a disposição do biossólido em pelo menos 75,30% (2.664,23 km²) da área do município, enquanto que 24,70% (873,93km²) apresentam restrições por se tratar de locais não recomendados para à aplicação desse tipo de material. / The sewage sludge is a hazardous waste according to NBR 10004/04, and when poorly managed, can adversely affect not only the environment and public health, to be the spread of disease agent. On the other hand, the sludge obtained from the sewage sludge is considered a great biofertilizer due to its composition, to be rich in organic matter nitrogen and phosphorus. This study aimed to evaluate the potential of the sludge coming from tanks / household septic tanks in the metropolitan region of Cuiabá (RMC) for final disposal on agricultural soils. The experiment of natural drying bed was developed in an outsourced laboratory with the aim of evaluating the quality of the sludge collected in pits neighborhoods Dom Aquino, Coxipó da Ponte, Morada da Serra, Boa Esperança and Jardim Universitário of septic tanks and transported by vehicles clean-pit. The experiment followed the same procedure in the treatment of sludge from sewage treatment plants. After this process, the material was sanitized with quicklime to 50% dry basis and undergo a maturation period of 30 days, then were subjected to laboratory analysis. The parameters were analyzed with respect to stability, the trace elements of metals and resistant pathogens. The results were compared with the current legislation standards. GIS techniques and geographic information systems (GIS) in order to identify potentially suitable for areas receiving biosolids were also used. According to the results, the drying bed natural exposure showed efficiency in dewatering and sludge stabilization, reaching levels lower than 10% humidity, the ratio between volatile and less than 0.10 total solids; with respect to the concentrations of trace elements of metals analyzed, all samples showed lower levels of biosolids to the maximum values allowed by CONAMA Resolution 375/06, including sample clean-truck fossa, which showed the highest levels of the analyzed parameters; after cleaning the sludge, the material presented quality Class A biosolids in relation to the concentration of pathogenic organisms; Finally, the study of the physical environment facilitated the disposal of biosolids at least 75.30% (2664.23 km ²) of the municipal area, while 24.70% (873,93km²) have restrictions because it is not local recommended for the application of this type of material.
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Developing an integrated concept for sewage sludge treatment and disposal from municipal wastewater treatment systems in (peri-)urban areas in VietnamKarius, Ralf 06 July 2011 (has links)
The study took place in Vietnam at Hanoi University of Science in the framework of the DAAD (German Academic Exchange Service) – “An advancement of the German-Vietnamese University partnerships”. The research has been supported by the program: “Wastewater and Solid Waste Management in Provincial Centers” and belongs to its technical component.
The present diploma thesis elaborates the current situation of sewage sludge management in Vietnam and is dealing with sludge characteristics from both domestic sewage treatment facilities and septic tanks. During the research, different treatment components and treatment facilities have been analyzed to carry out a comprehensive survey of sewage sludge types. In this thesis, a guideline (draft) was developed as a main result, which can be helpful to bridge the legislative gap for sewage sludge re-use in Vietnam.
In conclusion, an integrated concept has been developed, which recommends the application of selected proceeding elements to treat sewage sludge and the further utilization of re-useable materials in agriculture in a controlled and environmentally-safe manner.:Abbreviations .......................................................................................................................... 4
List of Figures ......................................................................................................................... 5
List of Tables .......................................................................................................................... 6
Acknowledgement .................................................................................................................. 7
Abstract .................................................................................................................................. 8
1 Introduction ................................................................................................................... 10
2 Legal framework for sewage sludge management in Vietnam ................................. 13
2.1 Background ........................................................................................................... 13
2.2 Institutional framework .......................................................................................... 13
2.3 Legal framework.................................................................................................... 15
2.4 Standards .............................................................................................................. 18
2.4.1 Technical standards ...................................................................................... 18
2.4.2 National standards ........................................................................................ 19
2.5 Current situation .................................................................................................... 20
3 Theoretical basis for the concept ................................................................................ 22
3.1 Sewage sludge ...................................................................................................... 23
3.1.1 Sewage sludge types .................................................................................... 27
3.1.2 Quantity .......................................................................................................... 30
3.1.3 Sludge volume ............................................................................................... 30
3.1.4 Sludge composition ....................................................................................... 34
4 Municipal wastewater treatment plants ...................................................................... 47
4.1 DEWATS ............................................................................................................... 47
4.2 Waste water management program .................................................................... 48
4.2.1 Results of sludge analysis ............................................................................ 50
4.3 Learned outcomes ................................................................................................ 54
5 Sludge treatment and disposal options ...................................................................... 56
5.1 Goals of sludge treatment .................................................................................... 56
5.2 Processing elements ............................................................................................ 58
5.2.1 Pre-treatment ................................................................................................. 59
5.2.2 Transportation................................................................................................ 60
5.2.3 Stabilization.................................................................................................... 60
5.2.4 Disinfection .................................................................................................... 65
5.2.5 Removal of water .......................................................................................... 65
5.2.6 Drying ............................................................................................................. 70
5.2.7 Agricultural uses and landscape measures ................................................ 70
5.2.8 Biological re-uses .......................................................................................... 71
5.2.9 Thermal disposal (energy recovery) ............................................................ 74
5.2.10 Land-filling ...................................................................................................... 76
6 Sewage sludge management concept ....................................................................... 78
6.1 Avoidance .............................................................................................................. 79
6.2 Treatment .............................................................................................................. 79
6.2.1 Proposed treatment concept ........................................................................ 81
6.3 Re-use or Disposal ............................................................................................... 84
6.3.1 Small-scale concept ...................................................................................... 85
6.3.2 Medium- and large-scale concept ................................................................ 85
6.4 Conclusion ............................................................................................................. 86
7 Guideline (draft) ............................................................................................................ 88
7.1 Formulation of a guidance document .................................................................. 88
8 Conclusion .................................................................................................................... 89
9 References .................................................................................................................... 92
10 Appendices ................................................................................................................ 97
a) Calculation of sludge amount .................................................................................. 97
b) Guideline (draft) ........................................................................................................ 99
Declaration .......................................................................................................................... 106 / Die Diplomarbeit wurde im Rahmen des Deutsch-Vietnamesischem Auslandsaustauschprogramms an der „Hanoi University of Science“ verfasst. Dieses Vorhaben wurde unterstützt von dem DAAD (Deutschen Akademischen Austausch Dienst), und ist im technischem Bereich des Programms “Wastewater and Solid Waste Management in Provincial Centers“ einzugliedern.
Die vorstehende Diplomarbeit beschäftigt sich mit dem aktuellen Klärschlammmanagement in Vietnam und liefert dabei detaillierte Resultate zu verschiedenen Klarschlammtypen aus kommunalen Abwasserbehandlungsanlagen. Bei den Untersuchungen wurden verschiedene Abwasser- und Klärschlammbehandlungsanlagen untersucht, um einen Überblick zu den gebräuchlichen Behandlungsmethoden in Vietnam zu erarbeiten. Zusätzlich wurden die institutionellen und rechtlichen Rahmenbedingungen überprüft. Der Entwurf einer Verordnung zur Verwertung von Klärschlamm in der Landwirtschaft wurde vorgelegt, um eine bestehende rechtliche Lücke in Vietnam zu schließen.
Mit dieser Arbeit wurde ein integriertes Konzept entwickelt, welches mittels verschiedene verfahrenstechnische Elemente den Klärschlamm behandelt und darauffolgend das verwertbare Material in ausgewählten landwirtschaftlichen Flächen in einer kontrollierten und umweltschonenden Weise verwertet.:Abbreviations .......................................................................................................................... 4
List of Figures ......................................................................................................................... 5
List of Tables .......................................................................................................................... 6
Acknowledgement .................................................................................................................. 7
Abstract .................................................................................................................................. 8
1 Introduction ................................................................................................................... 10
2 Legal framework for sewage sludge management in Vietnam ................................. 13
2.1 Background ........................................................................................................... 13
2.2 Institutional framework .......................................................................................... 13
2.3 Legal framework.................................................................................................... 15
2.4 Standards .............................................................................................................. 18
2.4.1 Technical standards ...................................................................................... 18
2.4.2 National standards ........................................................................................ 19
2.5 Current situation .................................................................................................... 20
3 Theoretical basis for the concept ................................................................................ 22
3.1 Sewage sludge ...................................................................................................... 23
3.1.1 Sewage sludge types .................................................................................... 27
3.1.2 Quantity .......................................................................................................... 30
3.1.3 Sludge volume ............................................................................................... 30
3.1.4 Sludge composition ....................................................................................... 34
4 Municipal wastewater treatment plants ...................................................................... 47
4.1 DEWATS ............................................................................................................... 47
4.2 Waste water management program .................................................................... 48
4.2.1 Results of sludge analysis ............................................................................ 50
4.3 Learned outcomes ................................................................................................ 54
5 Sludge treatment and disposal options ...................................................................... 56
5.1 Goals of sludge treatment .................................................................................... 56
5.2 Processing elements ............................................................................................ 58
5.2.1 Pre-treatment ................................................................................................. 59
5.2.2 Transportation................................................................................................ 60
5.2.3 Stabilization.................................................................................................... 60
5.2.4 Disinfection .................................................................................................... 65
5.2.5 Removal of water .......................................................................................... 65
5.2.6 Drying ............................................................................................................. 70
5.2.7 Agricultural uses and landscape measures ................................................ 70
5.2.8 Biological re-uses .......................................................................................... 71
5.2.9 Thermal disposal (energy recovery) ............................................................ 74
5.2.10 Land-filling ...................................................................................................... 76
6 Sewage sludge management concept ....................................................................... 78
6.1 Avoidance .............................................................................................................. 79
6.2 Treatment .............................................................................................................. 79
6.2.1 Proposed treatment concept ........................................................................ 81
6.3 Re-use or Disposal ............................................................................................... 84
6.3.1 Small-scale concept ...................................................................................... 85
6.3.2 Medium- and large-scale concept ................................................................ 85
6.4 Conclusion ............................................................................................................. 86
7 Guideline (draft) ............................................................................................................ 88
7.1 Formulation of a guidance document .................................................................. 88
8 Conclusion .................................................................................................................... 89
9 References .................................................................................................................... 92
10 Appendices ................................................................................................................ 97
a) Calculation of sludge amount .................................................................................. 97
b) Guideline (draft) ........................................................................................................ 99
Declaration .......................................................................................................................... 106
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PERFLUOROALKYL ACIDS AND OTHER TRACE ORGANICS IN WASTEDERIVED ORGANIC PRODUCTS: OCCURRENCE, LEACHABILITY, AND PLANT UPTAKERooney Kim Lazcano (7038074) 14 August 2019 (has links)
<p>Waste-derived organic products are nutrient-rich materials often applied to agricultural land as a fertilizer to enhance agricultural production and soil quality. Commercially available biosolid-based products, which are sold and distributed in bags or bulk, are rapidly gaining popularity for urban and suburban use. Although biosolid-derived products have many benefits, they may contain trace organic contaminants such as per- and polyfluoroalkyl acids (PFAAs) and pharmaceutical and personal care products (PPCPs), in varying levels, depending on waste source composition. These organic compounds have been used in a variety of consumer and industrial products and are known to accumulate in biosolids due to their recalcitrance in conventional wastewater treatment processes. Thus, the application of commercially available biosolids-based products on urban and suburban gardens may lead to transfer and accumulation of organic contaminants into food crops, raising food safety concerns. Most studies to date have focused on municipal biosolids application on agricultural lands with very few studies focused on commercial products available for home and urban gardens. For the latter, the evaluations of bioavailability and subsequent plant uptake of organic contaminants from biosolids have also often been conducted by adding organic contaminants to the growing media (e.g., soil or hydroponic) at a concentration that greatly exceed environmentally relevant concentrations. Moreover, there are currently no studies evaluating leaching and plant uptake potential of contaminants from commercially available (e.g., local stores) biosolids. The research described in this dissertation 1) assessed the occurrence of PFAAs and representative PPCPs in commercially available biosolid-based products and their porewater concentrations in saturated media as a measure of bioavailability and leachability; 2) investigated how heat-treatment, composting, blending and thermal hydrolysis processes on biosolids to convert them to commercial biosolid-based products affect PFAA concentrations in the production of commercial biosolid-based product; and 3) assessed the bioavailability and plant uptake of PFAAs and targeted PPCPs by kale and turnips grown in soil-less potting media amended with Milorganite (a commercially available biosolids-based fertilizer product) at the recommended rate and four times the recommended rate.</p><p>The biosolid-based products displayed varying levels of organic contaminants. Higher PFAA concentrations were detected in biosolid-based products compared to nonbiosolid-based products. The common treatment processes used in taking biosolids to commercially available products were ineffective in reducing PFAA levels in the products except for blending with other essentially PFAA-free materials, thus served as a simple dilution. Porewater concentrations of PFAAs and PPCPs as an indicator of leachability and bioavailability were higher for the less hydrophobic compounds (e.g., short-chain PFAAs and diphenhydramine and carbamazepine with lower octanol-water partition coefficient). Leachability alone did not explain the observed plant uptake potential of PFAAs and PPCPs. With similar leachability and molecular weight/size between diphenhydramine and carbamazepine, higher uptake was observed with a positively charged compound (diphenhydramine compared to a neutral compound (carbamazepine). However, not all positively charged compounds were taken up by the plant. Azithromycin, a positively charged compound, had lower uptake than other contaminants which may be due to its large molecular size compared to diphenhydramine. Higher concentrations of miconazole, triclosan, and triclocarban were found in the biosolids-fertilizer; however, these compounds had low leachabilities and limited uptake by plants. Also, for PPCPs, the application rates of biosolid-based products did not necessarily correlate with the higher uptake and translocation of contaminants to the above-ground portion of plants. </p><p>This study provides an evaluation of commercially available waste-derived organic products under condition comparable to home and urban garden setting. Although biosolids-based products can serve as alternatives to synthetic fertilizers, they contain higher levels of trace organic contaminants than nonbiosolid-organic products. Common biosolids treatment processes are ineffective for reducing the levels of trace organic contaminants in biosolids, particularly for PFAAs. Thus, it is critical to control the sources contributing to the higher level of these contaminants in biosolids-based products. Also, regulations (e.g., triclosan and triclocarban) and replacements (e.g., longer-chain PFAAs to short-chain PFAAs) of persistent trace organic chemicals have led to a reduction in their levels in biosolids-based products. Although longer chain PFAAs are more likely to bioaccumulate and persistent than the replacement short-chain alternatives, the current study has shown that the short-chain PFAAs are more readily taken up to edible parts of plants than longer-chain PFAAs even when applying at the recommended fertilizer rate. Thus, the current movement to replace longer chain PFAAs with short chains has the potential to result in higher total PFAA concentrations being bioavailable for plant uptake, thus increasing the risk of food contamination by PFAAs. </p>
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Avaliação quantitativa do risco microbiológico em águas e biossólidos: estado da arte / Quantitative microbial risk assessment: state of the art in water and biosolidsIgnoto, Raquel de Fátima 22 October 2010 (has links)
A avaliação quantitativa de risco microbiológico é o processo utilizado para estimar a probabilidade de infecção, doença ou morte após exposição a microrganismos patogênicos presente em águas, biossólidos, alimentos e ar. Essa pesquisa tem como objetivo descrever o estado da arte da avaliação qualitativa de risco microbiológico associadas a águas e biossólidos, bem como descrever as abordagens e etapas utilizadas na condução do processo, relatar a aplicabilidade e discutir as dificuldades e necessidades na condução da AQRM. Sendo uma pesquisa de caráter descritivo-explicativo, realizou-se revisão de literatura sobre a temática nas seguintes bases de dados: Scielo, LILACS, DEDALUS, MEDLINE e PUBMED e nos documentos produzidos pela Organização Mundial de Saúde e U.S. Environmental Protect Agency. Na literatura consultada verificou-se que a AQRM vem sendo utilizada desde o início da década de 1980 para estimar os riscos à saúde humana. Existem diferentes abordagens utilizadas na condução da ferramenta, diferem na forma de organizar e sistematizar as informações, porém são similares. A abordagem mais utilizada é a proposta pela NRC e consta de quatro etapas: identificação do perigo, avaliação de exposição, avaliação de dose-resposta e caracterização do risco. Constatou-se que a avaliação de exposição apresentase como a etapa mais complexa da AQRM, devido a: i) limitações metodológicas na determinação da concentração e viabilidade dos patógenos em águas e biossólidos e ii) escassez de dados de exposição e de consumo. Verificou-se que a utilização da ferramenta é proeminente na avaliação dos riscos decorrentes da exposição à patógenos presentes em águas de consumo, recreacionais e residuárias, bem como os decorrentes da exposição a solos e cultivos agrícolas fertilizados com biossólidos. É uma ferramenta que assume relevância no cenário internacional vem se consolidando no estabelecimento de valores-limite de patógenos presentes em diversas fontes, no desenvolvimento de normas, guias e legislações, bem como para discussões e implementação de planos de segurança da água e alimentar. Porém, é uma ferramenta pouco conhecida e empregada em nosso país que pode vir a atender às demandas atuais relacionadas a águas e biossólidos, tais como: i) estabelecimento de valores-limite e risco tolerável para patógenos, ii) proposição de métodos de tratamento e controle, iii) criação e revisão de normas, regulamentações e leis e iv) implementação de políticas públicas que visem a promoção e proteção da saúde humana / The quantitative microbial risk assessment is the process used to estimate the probability of infection, disease or death after exposure to pathogenic microorganisms present in water, biosolids, food and air. This research aims to describe the state of the art of quantitative microbial risk assessment associated with water and biosolids, and to describe the approaches and steps used in conducting the proceedings, report the applicability and discuss the difficulties and needs in the conduct of QMRA. As a search with a descriptive-explanatory character, there was a literature review on the subject on the following databases: SciELO, LILACS, DEDALUS, MEDLINE, PUBMED and in documents produced by the World Health Organization and the U.S. Environmental Protection Agency. In literature it was found that the QMRA has been used since the early 1980s to estimate the risk to human health. There are different approaches used in the conduct of the tool, they differ in the way of organizing and systematizing the information, but they are similar. The most used approach is the one proposed by the NRC and consists of four steps: hazard identification, exposure assessment, doseresponse assessment and risk characterization. It was found that the exposure assessment is presented as the most complex steps of QMRA due to: i) methodological limitations in determining the concentration and viability of pathogens in water and biosolids, and ii) lack of exposure data and consumption. It was verified that the use of the tool is prominent in assessing the risks from exposure to pathogens in drinking water, recreational water and wastewater, as well as from exposure to soils and crops fertilized with biosolids. It is a tool that is relevant in the international arena and has been consolidated in the establishment of limit values of pathogens present in different sources, in developing standards, guidelines and laws, as well as for discussion and implementation of plans for water and food security. However, it is a relatively unfamiliar tool used in our country that can come to attend current demands related to water and biosolids, such as: i) establishment of limit values for pathogens and tolerable risk, ii) proposition of methods of treatment and control, iii) creation and revision of standards, regulations and laws and iv) implementation of public policies for promotion and protection of human health
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Ciclagem de nutrientes e metais pesados em plantios de Eucalyptus grandis adubados com lodos de esgoto produzidos em diferentes estações de tratamento da região metropolitana de São Paulo / Nutrient and heavy metal cycling in Eucalyptus grandis plantations fertilized with sewage sludge from different sewage treatment plants in metropolitan region of Sao Paulo, BrazilFerraz, Alexandre de Vicente 26 January 2010 (has links)
A produção de lodo de esgoto vem aumentando exponencialmente com a multiplicação das estações de tratamento de esgoto (ETEs) e a sua disposição final tem se tornado um problema sanitário preocupante. Por ser um resíduo rico em matéria orgânica e nutrientes, muitas pesquisas vêm sendo desenvolvidas na busca de alternativas ecologicamente mais adequadas para o seu descarte. Este trabalho teve como objetivo verificar as diferenças entre lodos de esgoto (biossólidos), produzidos em três diferentes Estações de Tratamento de Esgotos da região metropolitana de São Paulo, quando utilizados como adubo em plantações de Eucalyptus grandis. Procurou-se também avaliar a influência deste resíduo sobre a ciclagem de nutrientes e sobre a dinâmica de metais pesados no ecossistema florestal. O estudo foi realizado na Estação Experimental de Ciências Florestais da ESALQ/USP em Itatinga-SP, cujo solo é predominantemente arenoso e de baixa fertilidade natural. O delineamento experimental utilizado foi em blocos aleatorizados, com 4 repetições e cinco tratamentos, sendo eles: 1)Testemunha Absoluta (TA), sem nenhuma adubação; 2) Fertilização mineral convencional (FM); 3) Aplicação de 15 Mg ha-1 de lodo de esgoto da ETE de Barueri (LB); 4) 15 Mg ha-1 de lodo de esgoto da ETE de São Miguel (LSM); 5) 15 Mg ha-1 de lodo de esgoto da ETE do Parque Novo Mundo (LPNM). Todos os tratamentos com lodo de esgoto foram complementados com potássio mineral (KCl), visto que o lodo é deficiente neste nutriente. O LB e o LSM foram condicionados com polieletrólitos, mas o LPNM foi condicionado com cal hidratada e cloreto férrico. O efeito dos diferentes tratamentos sobre os eucaliptos foi avaliado através de: inventários florestais semestrais, nutrição foliar, estimativa do folhedo produzido mensalmente, estimativa semestral de folhedo acumulado sobre o solo, avaliação da decomposição do folhedo no campo através de bolsas decompositoras, reflexo dos lodos sobre a fertilidade do solo, estimativa da biomassa e do estoque de nutrientes e metais pesados nos componentes do tronco (Lenho+Casca), nas folhas e nas raízes finas dos eucaliptos. Observou-se que a adubação dos eucaliptos com os lodos propiciou, em média, um incremento do volume de madeira da ordem de 65%, superior à testemunha (sem adubação) e similar ao observado no tratamento com fertilização mineral. A concentração dos nutrientes nas folhas dos eucaliptos tratados com os lodos, aos 6 meses de idade, apresentou uma elevação significativa dos nutrientes N, P, Ca, Cu, Fe e Zn em relação à testemunha. Mas, aos 42 meses, observou-se a tendência geral de redução da concentração de todos os nutrientes nas folhas, independente dos tratamentos. A adição dos lodos estimulou em 75% a produção de folhedo pelos eucaliptos, bem como um maior acúmulo de folhedo sobre o piso florestal. Conseqüentemente, houve uma maior transferência de nutrientes, via folhedo, das copas dos eucaliptos para a camada de serapilheira. De maneira geral, a aplicação da FM e dos lodos de esgoto melhorou a fertilidade do solo na linha de plantio (ponto de aplicação), principalmente na camada entre 0 e 5 cm de profundidade. Todavia, poucas mudanças foram observadas na produção de raízes finas em função dos diferentes tratamentos. O lodo de esgoto, quando condicionado na ETE com cal hidratada, tende a elevar o estoque de cálcio em todos os componentes do sistema solo-planta-serapilheira, podendo a longo prazo causar desbalanço nutricional e impactos prejudiciais ao ecossistema. Nos tratamentos com lodo de esgoto, foi observada uma maior concentração de metais pesados, em comparação à testemunha, nas folhas: Cu, Zn e Ni; no folhedo: Cu e Zn; no solo: Cu e Zn (na linha de plantio) e Zn (na entrelinha de plantio), apenas na camada de 0-5 cm de profundidade e nas raízes finas: Zn e Ni. É imprescindível, portanto, se conhecer previamente a concentração dos diferentes elementos no lodo de esgoto, antes de sua aplicação em plantios florestais. O monitoramento nutricional das árvores e da ciclagem dos nutrientes são práticas de fundamental importância para o bom manejo deste resíduo e do empreendimento florestal. / The production of sewage sludge increased exponentially with the enlargement of sewage treatment plants (ETEs, by its acronym in Portuguese). The final disposal of this product has always been a sanitary problem. Since it is a residue rich in organic matter and nutrients, several researches have been carried out, looking for adequate ecological alternatives for its disposal. This study aims to verify the differences among the sewage sludge (biosolids) from three different sewage treatment plants in the metropolitan region of Sao Paulo when used as fertilizers in Eucalyptus grandis plantations. Moreover it seeks to assess the influence of this residue in the nutrients cycling and in the heavy metals dynamic in forestry ecosystems. This research was carried out in the Experimental Station of Forestry Sciences of ESALQ/USP in Itatinga, Sao Paulo, where the soil is mainly sandy and of low natural fertility. The experimental delineation was of randomized blocks, with 4 replications and 5 treatments: 1) control (TA) without fertilization; 2) mineral conventional fertilization (FM); 3) application of 15 Mg ha-1 of sewage sludge from Barueri ETE (LB); 4) 15 Mg ha-1 of sewage sludge from Sao Miguel ETE (LSM); 5) 15 Mg ha-1 of sewage sludge from Parque Novo Mundo ETE (LPNM). Since the sewage sludge lacks mineral potassium (KCl), it was added to all the treatments. The LB and the LSM were conditioned with polyelectrolyte, but the LPNM was conditioned with CaOH and with FeCl3. The sewage sludge was applied in the planting rows. The effect of the different treatments on the eucalyptus trees was assessed by: six-monthly forestry inventories, leafs nutrition, estimation of monthly production of leaf fall, six-monthly estimation of leaf fall stocked in the soil, assessment of the decomposition of leaf fall in the field with decomposition bags, reflex of the sludge over the soil fertility, estimation of the biomass and the stock of nutrients and heavy metals in the trunk (stem wood + bark), in the leaves and in the fine roots of the eucalyptus trees. It was observed that the fertilization with sludge favored in average the increase of the wood volume around 65%, higher that the control (without fertilization) and similar to what observed in the treatment with mineral fertilization. The concentration of N, P, Ca, Cu, Fe and Zn in the leaves of the eucalyptus treated with the sludge, when six months old, increased significantly compared with the control. When the trees, of all the treatments were 42 months old, there was a decrease in the concentration of all nutrients in the leaves. The addition of sludge stimulated in 75% the production of leaf fall, as well as its high accumulation in the forestry soil. Consequently, the nutrients transfer was high, by the leaf fall, from the top of the trees to the litter. In general, the application of FM and of sewage sludge improved the soil fertility in the inter row (application place), mainly in the depth 0-5 cm. However, few changes were observed in the fine roots production regarding the different treatments. The sewage sludge, when conditioned in the ETE with CaOH, tends to increase the calcium stock in all the components of the system soil-plantlitter, what in long term may cause a nutritional imbalance and harmful impacts to the ecosystem. In the treatments with sewage sludge, a higher concentration of heavy metals in the leaves was observed in comparison with the control: Cu, Zn and Ni; in the leaf fall: Cu and Zn; in the soil: Cu and Zn (in the planting rows) and Zn (between-tree rows), only in the depth 0-5cm and in the fine roots: Zn and Ni. Therefore, before the application of sewage sludge in forestry plantations it is essential to know the concentration of the different elements present in it. The nutritionalmonitoring of the trees and the nutrients cycling are fundamental practices of essential importance for the good management of this residue and for the forestry farmer
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Lodo de esgoto em plantações de eucalipto: carbono, nitrogênio e aspectos da fotossíntese / Sewage sludge in eucalypt plantation: carbon, nitrogen and photosynthesis aspectsLira, Ana Cláudia Silva de 14 September 2006 (has links)
O tratamento de esgoto gera um resíduo, o lodo de esgoto, que tem potencial para promover o crescimento de plantas e aumentar a produtividade de cultivos. O objetivo geral do trabalho desenvolvido foi avaliar como esse resíduo aplicado em plantações de eucalipto altera os estoques de C e N, aspectos do processo fotossintético, da área e nutrientes foliares. O estudo foi conduzido na estação experimental de Itatinga - ESALQ/USP, com aplicação de doses até 40 t/ha de biossólido para cultivo de Eucalyptus grandis. Considerando a biomassa total acima do solo, os eucaliptos que receberam 10 t/ha de biossólido + K e P mineral (10+KP) e adubação mineral completa (AD) produziram, em média, 107,5 t/ha, 63% a mais do que a testemunha; além de maiores valores de conteúdo de C e N na biomassa. Não houve diferenças significativas entre os tratamentos para os conteúdos totais de C (F = 1,3450; p = 0,3096), N (F = 1,2183; p = 0,3536) e conteúdo de N mineral (F = 0,5192; p = 0,7218) no solo. Apenas o C do solo determinado por oxidação úmida foi alterado. A dose de 10 t/ha propiciou aumentos no C Walkley e Black em relação às maiores doses, mostrando que o desenvolvimento das árvores é mais importante para propiciar entradas de material orgânico no sistema do que a própria aplicação do biossólido. A utilização de biossólido alcalino, em superfície, propiciou baixas taxas de decomposição aos 5 anos após aplicação e não contribuiu para aumentar os estoques totais de C e N no solo. Os eucaliptos que receberam nutrientes, seja pela adubação mineral, seja pela aplicação de biossólido apresentaram maior área foliar. A diferença entre o maior IAF (4,3), do tratamento 40+K, e o controle superou uma unidade. As doses de biossólido polimerizado foram correlacionadas positivamente com os teores foliares de N, P, S, e Zn e com a clorofila do eucalipto com 3 meses de idade. Esse biossólido pode aumentar a fotossíntese líquida, quando as medições são realizadas no período da manhã, sendo também capaz de promover aumentos na eficiência do uso da água e no desenvolvimento de eucaliptos jovens. / The wastewater treatment generates a residue, the sewage sludge, that has potential to promote plants growth and to increase its productivity. The general aim of this research was to evaluate how the applied residue in eucalypt plantations modify C and N stocks, aspects of the photosynthetic process, leaf area and leaf nutrients. The study was developed at the experimental station of Itatinga - ESALQ/USP. The experiment was installed with application of rates up to 40 t/ha of biosolids in Eucalyptus grandis plantation. Considering the total biomass above the soil, the eucalypts that received 10 t/ha of biosolids + K and P mineral (10+KP) and complete mineral fertilization (AD) produced, on average, 107.5 t/ha, which represents 63% more than control treatment and larger values of C and N contents in the biomass. There were not significant differences among the treatments for total contents of C (F = 1.3450; p = 0.3096), N (F = 1.2183; p = 0.3536) and mineral N (F = 0.5192; p = 0.7218) in the soil. Just the soil carbon content, determined by wet oxidation, was altered. The 10 t/ha biosolids rate increased the Walkley and Black C in relation to the largest doses, showing that trees development is more important to input organic material in the system than the biosolids application. The alkaline biosolids application to the soil surface resulted in low decomposition rates, 5 years after application, and did not contribute to increase C and N total stocks in the soil. The eucalypts that received nutrients even by mineral fertilization or by biosolids application, presented larger leaf area. The difference between the higher LAI (4.3) observed (treatment 40+K) and the control treatment was one unit. The polymeric biosolids rates were positively correlated with N, P, S, and Zn concentrations and with chlorophyll in eucalypts leaves at 3 months of age. The studied biosolid can increase net photosynthesis, being also capable to promote the water use efficiency and young eucalypts development.
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Avaliação da matéria orgânica de solos tratados com lodo de esgoto: uso de ferramentas quantitativas e espectroscópicas / Evaluation of organic matter from soils treated with sewage sludge: use of quantitative and spectroscopic toolsAvalhães, Cintia Carla 09 April 2014 (has links)
A reciclagem agrícola do lodo de esgoto devidamente tratado é uma boa opção, pois transforma o resíduo orgânico em um importante insumo agrícola. Entretanto, a aplicação do lodo de esgoto pode alterar a quantidade e a estabilidade da matéria orgânica do solo. Com a presente pesquisa, objetivou-se avaliar os efeitos de doses de lodo de esgoto na matéria orgânica de dois solos (um Latossolo Vermelho distrófico sob floresta de eucalipto e um Latossolo Vermelho distroférrico sob cultivo de milho) por meio de técnicas quantitativas e espectroscópicas. O experimento I, sob cultivo de milho, foi instalado em Jaguariúna-SP, constituiu-se de 5 doses acumuladas de lodo de esgoto da ETE de Barueri, aplicadas de 1999 a 2005: 0; 30; 60; 120 e 240 t ha-1 (em base seca). O experimento II, sob floresta de eucalipto, foi instalado em dezembro de 2004, em área comercial da empresa da Suzano Papel e Celulose, em Angatuba - SP. Aplicou-se, uma única vez, 4 doses de lodo de esgoto da ETE de Jundiaí (0; 7,7; 15,4 e 23,1 t ha-1 em base seca). Nas amostras de solo foram determinados os conteúdos de carbono, por meio de análise elementar (CHN), e então, calculou-se o grau de humificação da matéria orgânica utilizando a Fluorescência Induzida por Laser (FIL). Com base nesses resultados, foram selecionadas algumas amostras para o fracionamento químico da matéria orgânica do solo e, por meio de técnicas espectroscópicas (FTIR, UV-vis, RMN e Fluorescência de UV-vis), foi realizado um estudo aprofundado da influência do lodo de esgoto nas substâncias húmicas do solo, bem como, em seu estágio de humificação. Pode-se verificar um aumento na concentração de carbono no solo com a aplicação do lodo de esgoto em ambos experimentos, bem como um aumento da alifaticidade e, conseqüentemente, diminuição da aromaticidade das substâncias húmicas, resultado da incorporação de matéria orgânica fresca, não compostada / Agricultural recycling of sewage sludge treated properly is a good option, since it transforms organic waste into a major agricultural input. However, the application of sewage sludge can alter the amount and stability of soil organic matter. The present work aimed to evaluate the effects of sewage sludge levels on organic matter from two different soils (an Oxisol under eucalyptus forest and an Oxisol under corn) through quantitative and spectroscopy techniques. The experiment, under corn, was installed in Jaguariuna-SP, consisted of 5 accumulated levels of sewage sludge from ETE Barueri, implemented from 1999 to 2005: 0, 30, 60, 120 and 240 t ha-1. Experiment II, in eucalyptus forest, was installed in December 2004, the commercial company Suzano Papel e Celulose, in Angatuba - SP. Applied only once, 4 doses of sewage sludge from Seawater Sewage Treatment from Jundiai (0, 7.7, 15.4 and 23.1 t ha-1 on a dry basis). Soil samples were determined carbon content by means of elemental analysis (CHN), and then calculated the degree of humification of organic matter using Laser Induced Fluorescence (LIF). Based on these results, we selected some samples for chemical fractionation of soil organic matter, and by means of spectroscopic techniques (FTIR, UV-vis, NMR and Fluorescence UV-vis), was conducted a detailed study of the influence of sludge sewage humic substances on the ground as well as on their stage of humification. One can observe an increase in the amount of carbon in the soil application of sewage sludge in both experiments, as well as an increase in aliphaticity and consequently decreased aromaticity of humic substances, resulting from the incorporation of fresh organic matter, noncomposted
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Caracterização microbiológica, química e presença de poluentes orgânicos em amostras de lodo de esgoto de São Paulo / Microbiological and chemical characterization and presence of organic pollutants in sewage sludge samples from São PauloNascimento, Altina Lacerda 04 April 2016 (has links)
Objetivou-se com este trabalho avaliar o potencial agrícola do lodo de esgoto produzido no estado de São Paulo, bem como, verificar a possibilidade de interação entre a composição química e a abundância relativa de bactérias no lodo. Foram realizadas coletas de amostra de lodo de esgoto em 19 estações de tratamento de esgoto, em três épocas distintas. Nas amostras provenientes das três épocas foram determinados as concentrações dos 16 hidrocarbonetos policíclicos aromáticos (HPAs) listados como prioritários no monitoramento ambiental pela USEPA (acenafteno, acenaftileno, antraceno, benzo(a)antraceno, benzo(a)pireno, benzo(b)fluoranteno, benzo(ghi)perileno, benzo(k)fluoranteno, criseno, dibenzo(a,h)antraceno, fenantreno, fluoranteno, fluoreno, indeno(1,2,3-cd)pireno, naftaleno e pireno). Nas amostras da segunda época de coleta, além da presença de HPAs, determinou-se as concentrações de poluentes orgânicos emergentes (hormônios, produtos farmacêuticos e produtos de uso industrial), realizou-se a caracterização completa segundo a Resolução CONAMA 375/2006 (umidade, pH, N-Kjeldahl e inorgânico, carbono orgânico, cálcio, potássio, fósforo, magnésio, enxofre, boro, cobre, ferro, níquel, manganês, molibdênio, selênio, zinco, alumínio, arsênio, bário, cádmio, cromo, chumbo, mercúrio e sódio) e a caracterização da comunidade bacteriana através de metodologia independente de cultivo (sequenciamento illumina). Os macronutrientes em maiores concentrações no lodo de esgoto são: N > Ca > S > P > Mg > K. Os elementos inorgânicos Ni e Zn apresentaram concentração superior à máxima permitida para utilização agrícola pela resolução Conama 375/2006 em 1 e 3 amostras, respectivamente. A substância inorgânica que mais limita o enquadramento do lodo de esgoto como adubo orgânico (Instrução Normativa 27/2006) é o Hg. Os compostos benzilparabeno, bisfenol AF (BPAF), ácido perfluorooctanoico (PFOA) e tetrabromobisfenol A (TBBPA) não foram detectados. Por outro lado, cimetidina, metilparabeno, bisfenol A (BPA) e triclocarban foram detectados nas 19 amostras avaliadas. O composto presente em maior concentração é o triclocarban. As concentrações de hidrocarbonetos policíclicos aromáticos são baixas, de acordo com a norma Europeia. Os filos Proteobacteria e Bacteroidetes estão presentes em maior abundância relativa. Existe uma comunidade bacteriana núcleo nas estações de tratamento de esgoto do estado de São Paulo, composta por 81 gêneros, presentes nas 19 ETEs avaliadas, dos quais, os que estão em maior abundância relativa são Treponema, Clostridium, Propionibacterium, Syntrophus e Desulfobulbus. A elevação do pH a valores próximos de 12 reduz a diversidade microbiana. Considerando a abundância relativa e a composição química do lodo de esgoto, as estações podem ser agrupadas em três grupos distintos, sendo que um deles é influenciado principalmente pelos teores de Ca, Zn e Cu, o outro pelos teores de Fe e S e o terceiro grupo que foi influenciado pelos demais fatores avaliados. / The aim of this work was to evaluate the agricultural potential of sewage sludge produced in the São Paulo state - Brazil, as well as to verify the possibility of interaction between the chemical composition and sewage sludge bacterial abundance. Samples were collected from 19 wastewater treatment plants in three different periods. On the samples from the three times were determined the presence and concentrations of 16 polycyclic aromatic hydrocarbons (HPAs) that are listed as priorities in environmental monitoring by the USEPA (acenaphthene, acenaphthylene, anthracene, benzo (a) anthracene, benzo (a) pyrene, benzo (b) fluoranthene, benzo (ghi) perylene, benzo (k) fluoranthene, chrysene, dibenz (a, h) anthracene, phenanthrene, fluoranthene, fluorene, indeno (1,2,3-cd) pyrene, naphthalene and pyrene). On the samples of the second collect time, besides HPAs, were determined the concentrations of emerging organic pollutants (hormones, pharmaceuticals and industrial products). It was performed the complete characterization according to CONAMA 375/2006 (moisture, pH, Kjeldahl and inorganic Nitrogen, organic carbon, calcium, potassium, phosphorus, magnesium, sulfur, boron, copper, iron, nickel, manganese, molybdenum, selenium, zinc, aluminum, arsenic, barium, cadmium, chromium, lead, mercury and sodium); and characterization of bacterial communities through cultivation-independent methods (Illumina sequencing). Macronutrients in higher concentrations in sewage sludge are: N > Ca > S > P > Mg > K. The inorganic elements Ni and Zn showed up in higher concentration than the maximum allowable for agricultural use by CONAMA Resolution 375/2006, at 1 and 3 samples, respectively. The inorganic element that most limits sewage sludge usage as organic fertilizer (MAPA, 2006) is the Hg. The compounds benzylparaben, bisphenol AF (BPAF), perfluorooctanoic acid (PFOA) and tetrabromobisphenol A (TBBPA) were not detected. On the other hand, methylparaben, cimetidine, bisphenol A (BPA) and triclocarban were detected in all 19 samples. The compound present in highest concentration is triclocarban. The concentrations of polycyclic aromatic hydrocarbons are low, according to the European standard. Proteobacteria and Bacteroidetes phyla are present in greatest relative abundance. There is a bacterial core in the sewage sludge treatment plants of the São Paulo State, comprising 81 genera present in all WWTPs evaluated. Those who are at a higher relative abundance are Treponema, Clostridium, Propionibacterium, Syntrophus and Desulfobulbus. The elevation of pH to values close to 12 reduces the microbial diversity. Considering the relative abundance and chemical composition of sewage sludge, the stations can be grouped into three distinct groups, one of which is influenced mainly by Ca, Zn and Cu, the other by Fe and S and the third group that was influenced by the others evaluated factors.
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