Please read the abstract in the section 00front of this document / Thesis (PhD(Water Resource Management))--University of Pretoria, 2008. / Microbiology and Plant Pathology / PhD / unrestricted

The prolonged challenges and dire consequences of poor sanitation, especially in developing economies, call for the exploration of new sustainable technologies. These need to be: capable of effectively treating human faecal wastes without any health or environmental impacts; scalable to address rapid increases in population and urbanization; capable of meeting environmental regulations and standards for faecal management; and competitive with existing strategies. Further and importantly, despite its noxiousness and pathogenic load, the chemical composition of human biowaste (HBW) indicates that it may be considered to be a potentially valuable, nutrient-rich renewable resource, rather than a problematic waste product. This doctoral study therefore investigated microwave hydrothermal carbonization (M-HTC) as a sanitation technology for processing HBW - to convert it into a safe, pathogen-free material, while also recovering inherent value and providing an economic base to sustain the technology. To this end, the products of M-HTC treatment of sewage sludge, human faecal sludge, synthetic faecal simulant and human faeces were characterized with a suite of techniques and tests to demonstrate pathogenic deactivation, and the intrinsic value of the resultant solid char and liquor.

This diploma paper deals with contemporary practice in dispose of biodegradable waste, especially biodegradable communal waste (biowaste) in the Czech Republic. It explains fundamental terms, points out relevant legal rules and describes methods of biowaste handling. It evaluates collection and utilization systems in two cities in the way of comparison method. It compares them from cost and benefits (economic, environmental) points of view. The main purpose of the diploma paper is general introduction into the issue, pointing out negative effect of biowaste landfilling and presentation of actual systems of utilization. Also the work points out contemporary trend consisting in raising separation and reducing biodegradable communal waste landfilling.

<p>The main project Dry preservation of food waste from households includes a new technique concerning drying and storage of dried biowaste as well as a study of the sorting of household waste and further usage of the dried biowaste. A question asked in the project is, can the dried biowaste be used as a soil amendment? If organic waste is used as a soil amendment, precaution concerning hygienic safety risks has to be accounted for. The objective of this M. Sc. Thesis Work was to first find a suitable method to attain hygienic safety through a literature study, to test and evaluate the method and to test if a method changes the composition or structure of the material. An existing recipe for food waste was developed and used throughout the work.</p><p>Heating of the dried biowaste is probably the most suitable method to reach and attain a hygienically safe product. Three time-temperature proportions were tested, 55, 70 and 80°C. The results show that a raise in temperature lead to a change in the composition of the dried biowaste, most distinctively for the highest temperature. Nitrogen losses of 21% of the total nitrogen content were noticed. A composting experiment showed that the biowaste heated to the highest temperature was decomposed to a higher degree. It does not, however, seem like a heating process will decrease the possibility to use dried biowaste as a soil improvement.</p> / <p>Projektet Torrkonservering av matavfall från hushåll innefattar en ny teknik för torkning och lagring av bioavfall, hushållens sortering och vidare användning av det torkade materialet. För att sluta det naturliga kretsloppet utreds om det torkade bioavfallet kan användas som ett jordförbättringsmedel. När organiskt avfall ska användas som ett jordförbättringsmedel ställs krav på hygienisk säkerhet. Examensarbetets syfte var att, genom litteraturstudier, utreda lämplig hygieniseringsmetod att vidare testa praktiskt, samt att testa om en hygieniseringsprocess medför några förändringar på det torkade bioavfallets materialegenskaper. Ett befintligt standardrecept på matavfall vidareutvecklades och användes.</p><p>Resultaten tyder på att upphettning av det torkade bioavfallet förmodligen är den mest lämpliga hygieniseringsmetoden. Tre olika tid- temperaturförhållanden testades, 55, 70 och 80°C. Laborationer och analyser tyder på att det torkade bioavfallet genomgår en viss förändring av den kemiska sammansättningen vid upphettning, vilket är tydligast för den högsta hygieniseringstemperaturen. Bland annat sker kväveförluster på upp till 21 % av totalkvävet. Komposteringstester visar på att nedbrytningsgraden är högst för bioavfall som hygieniserats vid den högsta temperaturen. Det verkar inte som om hygienisering, genom upphettning, minskar möjligheten att använda torkat bioavfall som ett jordförbättringsmedel.</p>

<p>The main project Dry preservation of source-separated organic household wastes involves a new technique for treatment of biowaste through drying. Investigations are going on to determine how the dried biowaste best can be used to close the natural circular flow of nutrients. The objective of this degree project is to determine if the dried biowaste can be used as a soil conditioner. By restoring the nutrients in the material to the ground, the natural circular flow is closed. A declaration of contents, including the nutrient levels, C/N ratio, pH and the electrical conductivity of the dried biowaste, was constructed and a germination test was done to make sure that the material did not inhibit sprouting. Further on a method was developed to study the decomposition process, and in particular the nitrogen mineralization of the dried biowaste. This method was then used practically.</p><p>The results of this degree project indicate that the decomposition capacity of the dried biowaste is very good. The germination test showed that the material in a diluted form (up to 50 % dried biowaste) did not inhibit sprouting. The examination of the nitrogen mineralization showed a fast liberalisation of nutrients available to plants, with only a shorter period of nitrogen immobilization. Together these results imply that the dried material could function well as a soil conditioner.</p> / <p>Projektet Torrkonservering av matavfall från hushåll innefattar en helt ny teknik för behandling av bioavfall genom torkning. Undersökningar pågår angående hur det torkade bioavfallet bäst kan användas för att sluta det naturliga kretsloppet. Examensarbetets huvudsyfte var, som ett led i dessa undersökningar, att utreda om det torkade bioavfallet kan användas som ett jordförbättringsmedel. Genom att tillföra bioavfallet till jord så återförs näringen i materialet till marken och kretsloppet sluts. En varudeklaration, med materialets näringshalter, C/N-kvot, pH och elektrisk konduktivitet, togs fram och ett groningstest utfördes för att kontrollera att bioavfallet inte var groningshämmande. Vidare utvecklades en metod för att studera det torkade bioavfallets nedbrytningsegenskaper i form av dess kvävemineralisering. Denna metod användes därefter praktiskt.</p><p>Resultatet av detta examensarbete tyder på att torkat bioavfall har mycket goda nedbrytningsegenskaper. Groningsförsöket visade att materialet i utspädd form (upp till 50 % torkat bioavfall) inte är groningshämmande, och mineraliseringsförsöket visade på en snabb frigörelse av växttillgängligt kväve, och en immobiliseringsperiod på ett par veckor. Tillsammans indikerar dessa resultat att det torkade materialet kan fungera väl som ett jordförbättringsmedel.</p>

<p>ABSTRACT</p><p>Anaerobic digestion is one way of handling biowaste and generating energy in the form of methane, biogas.</p><p>This study shows that spore forming bacterias survive the process of pasteurisation and anaerobic digestion in biogas plants. It has also been established that both the nonpasteurised-and digestion- waste contains pathogen spore forming bacterias. Two Swedish full-scale</p><p>commercial biogas plants were sampled before pasteurisation, after pasteurisation and after digestion on 10 occasions with one week intervals. The samples were analysed quantitatively</p><p>and qualitatively, with biochemical methods, for Clostridium spp and Bacillus spp.</p><p>Polymerase Chain Reaction, a biomolecular method, was used for</p><p>C. chauvei analysis, with C. chauvei specific primers. For this analyse the biogas plants were sampled at 11 occasions.</p><p>Survival of pathogenic spore forming bacteria in digestion residue may be a health risk for both humans and animals. The digested residue may be used as fertiliser on arable land and the risk of contamination by pathogenic Clostridium spp and Bacillus spp is hard to assess, but can not be neglected.</p>

The main project Dry preservation of source-separated organic household wastes involves a new technique for treatment of biowaste through drying. Investigations are going on to determine how the dried biowaste best can be used to close the natural circular flow of nutrients. The objective of this degree project is to determine if the dried biowaste can be used as a soil conditioner. By restoring the nutrients in the material to the ground, the natural circular flow is closed. A declaration of contents, including the nutrient levels, C/N ratio, pH and the electrical conductivity of the dried biowaste, was constructed and a germination test was done to make sure that the material did not inhibit sprouting. Further on a method was developed to study the decomposition process, and in particular the nitrogen mineralization of the dried biowaste. This method was then used practically. The results of this degree project indicate that the decomposition capacity of the dried biowaste is very good. The germination test showed that the material in a diluted form (up to 50 % dried biowaste) did not inhibit sprouting. The examination of the nitrogen mineralization showed a fast liberalisation of nutrients available to plants, with only a shorter period of nitrogen immobilization. Together these results imply that the dried material could function well as a soil conditioner. / Projektet Torrkonservering av matavfall från hushåll innefattar en helt ny teknik för behandling av bioavfall genom torkning. Undersökningar pågår angående hur det torkade bioavfallet bäst kan användas för att sluta det naturliga kretsloppet. Examensarbetets huvudsyfte var, som ett led i dessa undersökningar, att utreda om det torkade bioavfallet kan användas som ett jordförbättringsmedel. Genom att tillföra bioavfallet till jord så återförs näringen i materialet till marken och kretsloppet sluts. En varudeklaration, med materialets näringshalter, C/N-kvot, pH och elektrisk konduktivitet, togs fram och ett groningstest utfördes för att kontrollera att bioavfallet inte var groningshämmande. Vidare utvecklades en metod för att studera det torkade bioavfallets nedbrytningsegenskaper i form av dess kvävemineralisering. Denna metod användes därefter praktiskt. Resultatet av detta examensarbete tyder på att torkat bioavfall har mycket goda nedbrytningsegenskaper. Groningsförsöket visade att materialet i utspädd form (upp till 50 % torkat bioavfall) inte är groningshämmande, och mineraliseringsförsöket visade på en snabb frigörelse av växttillgängligt kväve, och en immobiliseringsperiod på ett par veckor. Tillsammans indikerar dessa resultat att det torkade materialet kan fungera väl som ett jordförbättringsmedel.

The main project Dry preservation of food waste from households includes a new technique concerning drying and storage of dried biowaste as well as a study of the sorting of household waste and further usage of the dried biowaste. A question asked in the project is, can the dried biowaste be used as a soil amendment? If organic waste is used as a soil amendment, precaution concerning hygienic safety risks has to be accounted for. The objective of this M. Sc. Thesis Work was to first find a suitable method to attain hygienic safety through a literature study, to test and evaluate the method and to test if a method changes the composition or structure of the material. An existing recipe for food waste was developed and used throughout the work. Heating of the dried biowaste is probably the most suitable method to reach and attain a hygienically safe product. Three time-temperature proportions were tested, 55, 70 and 80°C. The results show that a raise in temperature lead to a change in the composition of the dried biowaste, most distinctively for the highest temperature. Nitrogen losses of 21% of the total nitrogen content were noticed. A composting experiment showed that the biowaste heated to the highest temperature was decomposed to a higher degree. It does not, however, seem like a heating process will decrease the possibility to use dried biowaste as a soil improvement. / Projektet Torrkonservering av matavfall från hushåll innefattar en ny teknik för torkning och lagring av bioavfall, hushållens sortering och vidare användning av det torkade materialet. För att sluta det naturliga kretsloppet utreds om det torkade bioavfallet kan användas som ett jordförbättringsmedel. När organiskt avfall ska användas som ett jordförbättringsmedel ställs krav på hygienisk säkerhet. Examensarbetets syfte var att, genom litteraturstudier, utreda lämplig hygieniseringsmetod att vidare testa praktiskt, samt att testa om en hygieniseringsprocess medför några förändringar på det torkade bioavfallets materialegenskaper. Ett befintligt standardrecept på matavfall vidareutvecklades och användes. Resultaten tyder på att upphettning av det torkade bioavfallet förmodligen är den mest lämpliga hygieniseringsmetoden. Tre olika tid- temperaturförhållanden testades, 55, 70 och 80°C. Laborationer och analyser tyder på att det torkade bioavfallet genomgår en viss förändring av den kemiska sammansättningen vid upphettning, vilket är tydligast för den högsta hygieniseringstemperaturen. Bland annat sker kväveförluster på upp till 21 % av totalkvävet. Komposteringstester visar på att nedbrytningsgraden är högst för bioavfall som hygieniserats vid den högsta temperaturen. Det verkar inte som om hygienisering, genom upphettning, minskar möjligheten att använda torkat bioavfall som ett jordförbättringsmedel.

Kyoto University (京都大学) / 0048 / 新制・課程博士 / 博士(工学) / 甲第17542号 / 工博第3701号 / 新制||工||1563(附属図書館) / 30308 / 京都大学大学院工学研究科都市環境工学専攻 / (主査)教授 高岡 昌輝, 教授 田中 宏明, 教授 米田 稔 / 学位規則第4条第1項該当

Orientador: Prof. Dr. Dácio Roberto Matheus / Coorientadora. Profª. Drª. Neusa Serra / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Ciência e Tecnologia Ambiental, Santo André, 2018. / No Brasil, menos de 0,5% da fração orgânica dos resíduos sólidos urbanos (FORSU) é reciclada. O primeiro capítulo revisa sistematicamente estudos que comparam o ciclo de vida da FORSU quando destinada para a compostagem e a digestão anaeróbia. A revisão aponta lacunas metodológicas na análise do ciclo de vida (ACV) dos subsistemas energético e agrícola e a ausência de discussão sobre a FORSU em ambientes tropicais. No subsistema energético não se tem atentado para a dinâmica de geração e regulação de energia ao avaliar as substituições de diferentes matrizes. A redução das emissões de uso no solo dos fertilizantes substituídos é a principal lacuna do subsistema agrícola, que tem se limitado a análise do estoque de carbono e da redução da produção de fertilizantes. O segundo capítulo analisa o ciclo de vida da FORSU considerando as condições de ambiente tropical. Para tanto, cenários de manejo e gestão foram construídos para compostagem (doméstica e centralizada) e digestão anaeróbia (geração elétrica e biometano), a partir das características de gestão dos RSU e climáticas da Região Metropolitana de São Paulo, considerando as lacunas de análise identificadas no capítulo primeiro. Os cenários resultaram em potencial de aquecimento global de 220,0 a -480,7 kg CO2eq, acidificação de 1,7 a -4,3 kg SO2eq e eutrofização de 0,6 a -4,6 PO43-eq por tonelada destinada a compostagem e 215,6 a -510,2 kg CO2eq, 3,3 a -24,7 kg SO2eq e 0,3 a 3,0 PO43-eq para digestão anaeróbia. Os principais ganhos estão na substituição de ureia e estoque de carbono no solo para compostagem e substituição de carvão na produção elétrica para digestão anaeróbia. No cenário realista de gestão, 3,57 a 3,93 milhões de toneladas de CO2eq ao ano são reduzidas se comparado ao aterramento. Os potenciais de acidificação e eutrofização podem ser reduzidos com a redução no uso de ureia visto que, mesmo na maior metrópole da América Latina, cerca de 70% do composto produzido pode ser aplicado na RMSP e o restante aplicado a menos de 100 km. A integração do setor de resíduos com outros setores, como agrícola e energético ainda é um desafio para a gestão de RSU. Todavia, nesta integração se encontra a maior parcela de ganhos ambientais da destinação da FORSU para compostagem ou digestão anaeróbia. / Less than 0.5% of organic fraction of municipal solid waste (OFMSW) is recycled in Brazil. First chapter systematically reviews studies comparing composting and anaerobic digestion of OFMSW in life cycle approaches. The review points out some methodological gaps in life cycle assessment of energetic and agricultural subsystems and absence of discussion about OFMSW in tropical environments. In energetic subsystem, studies have not observed power generation and regulation dynamics for choosing energy source substitution. The absence of reduction of emissions due to use on land of substituted fertilizers is the main gap in agricultural subsystem, limited to carbon storage and reduction in production of fertilizers. Second chapter assesses the life cycle of OFMSW considering tropical conditions. Therefore, technical and management scenarios were developed for composting (domestic and industrial) and anaerobic digestion (power generation and biomethane) based on climatic and management context of São Paulo's Metropolitan Region, considering the identified gaps in first chapter. The scenarios resulted in potentials of global warming 220,0 to 480,7 kg CO2eq, acidification 1,7 a -4,3 kg SO2eq and eutrophication 0,6 a -4,6 PO43eq per ton treated by composting and 215,6 a -510,2 kg CO2eq, 3,3 a -24,7 kg SO2eq e 0,3 a -3,0 PO43-eq by anaerobic digestion. The main benefits are substitution of urea and carbon storage in soil for composting and substitution of power from coal for anaerobic digestion. For a realistic management scenario 3.57 to 3.93 million tons CO2eq by year might be saved compared to landfilling. Acidification and eutrophication potentials might be reduced with urea use on land diminishment, as even in largest metropolis of Latin American, more than 70% can be applied in agriculture inside metropolis area and the rest transported to less than 100 km. Waste management sector integration with other sectors, as agriculture and energy still poses a challenge to MSW management in Brazil. Although, in this integration we found the greatest environmental benefits of composting and anaerobic digestion of OFMSW.