This study investigated the fuel properties, engine performances, and emissions of two biodiesels and diesel. The fuels examined were D100 (ultra-low sulfur diesel), B20 (20% palm biodiesel +80% ultra-low sulfur diesel) and B100 (palm biodiesel). The fuel properties analysis results showed that the benefits of biodiesel were high cetane value, extremely low sulfur and aromatic contents, and good lubricity. While the defects of biodiesel were high pour point. The particulates emitted from the burning of D100, B100, B20 were mainly fine particulates, also known as young aerosols. Particles smaller than 2.5 µm easily enter the trachea and bronchus via the upper respiratory tract, finally deposit on the alveolus, which could cause severe injury to human health. The emission of soluble organic fraction (SOF) from diesel engine using D100, B100 and B20 were 23.2%, 19.9% and 20.2%, respectively. The SOF of D100 is slightly higher than B100 and B20. It suggested that adding biodiesel into diesel can decrease SOF and thus reduce the potential danger to human health. The original total PAHs concentration of tail gas emitted from engines using D100, B100 and B20 were 241, 50.6 and 98.8 µg/m3, respectively. Adding 20% biodiesel into D100 could reduce 59.0% of PAHs emission. Moreover, the original total BaPeq concentration of tail gas emitted from diesel engines using D100, B100 and B20 were 0.714, 0.509 and 0.570 µg/m3, respectively. Adding 20% biodiesel into D100 could also reduce 20.2% of total BaPeq emission. Hence, adding biodiesel into diesel can effectively reduce the emission of PAHs and the potential danger to human health. The emission factors of carbonyl compounds from diesel engines using D100, B100 and B20 were 395, 1,170 and 326 mg/BHP-hr, respectively. carbonyl compounds of B100 were obviously higher than D100 and B20. The results indicated that using pure palm biodiesel in diesel engine can increased the emission of carbonyl compounds. However, adding 20% biodiesel into D100 can effectively reduce 17.5% of carbonyl compounds emission. Keyword: ultra-low sulfur diesel, palm biodiesel, fuel properties¡BThe emission of soluble organic fraction (SOF)¡BPAHs¡Bcarbonyl compounds¡C

The effect of ammonia on anaerobic digestion of the organic fraction of municipal solid wastes (OFMSW) was investigated in this study. This study involved two sets of experiments. First set involved the investigation of ammonia toxicity on AD of synthetic OFMSW only (SW), at three different phases and pH 7.5, 8.0 and 8.5. Phase 1 was the Batch Methane Potential (BMP) phase. BMP tests were conducted under ammonia concentration of 2500 mg/L, 5000 mg/L, 7500 mg/L and 10,000 mg/L and at pH 7.5, 8.0, and 8.5, using 500 mL Kimax® glass bottles. The total working volume of the mixture was 300 mL comprising 120 mL of mesophilic anaerobically digested inoculums, 30 g of OFMSW, various TAN concentrations ranging from 2,500, 5,000, 7,500 to 10,000 mg/L, and equal portions of buffer in form of NaHCO3 and KHCO3. The second phase of the experiment examined whether the tolerance of the bacteria to high ammonia concentration would improve by acclimating the microbes to high ammonia concentrations, through gradual TAN loading. TAN concentration was increased gradually at pH 7.5, 8.0 and 8.5 weekly. The third phase of the experiment was Semi-continuous batch phase. This phase examined the possibility of reducing the inhibitory effect of ammonia on AD, batch reactors at pH values of 8.0 and 8.5 containing initial TAN concentrations of 7500 mg/L and 10,000 mg/L. 3 g of the digestate containing high ammonia concentration(s) was replaced with fresh substrate at every 4 days, 7 days and 15 days. The second set of experiment involved study of the effects of ammonia on anaerobic digestion of OFMSW with real landfill leachate (SW+L). Phase 1 was BMP in which the effect of ammonia was examined at TAN concentrations of 7,500 and 10,000 mg/L. The phase 2 of the (SW+L) gradual TAN TAN loading. The possibility of adapting mesophilic bacteria to high ammonia concentration was examined. The results of the study confirmed that ammonia is toxic to AD, at high concentrations. Biogas production reduced with increase in TAN concentration. Reduction in Cumulative Biogas Production (CBP) compared with control reactors was as much as 43 %, 64 % and 77 % in reactors containing 7500 mg/L TAN at pH 7.5, pH 8.0 and pH 8.5. CBP reduced to 80-85 % in reactors containing 10,000 mg/L TAN across the pH examined. Also, replacing 3g of digestate containing high TAN concentrations of 7500 mg/L and 10,000 mg/L with 3 g fresh substrate improved the activity of the mesophilic bacteria as seen in the surges in biogas production when fresh substrate was injected into the reactors. Similar results were obtained on effect of ammonia on AD of OFMSW mixed with real landfill leachate to simulate an anaerobic bioreactor landfill. CBP reduced as the TAN concentration increased. Compared with control reactors, reactors containing 7500 mg/L TAN at pH 8.0 and pH 8.5 had 61 % and 80 % reduction in CBP. Likewise, reactors containing 10,000 mg/L TAN at pH 8.0 and pH 8.5 had 68 % and 85 % reduction in CBP, compared with control reactors. Study confirmed that pH influenced the toxicity and composition of Total Ammonia Nitrogen (TAN). At high pH (i.e. 8.5), FAN component of TAN was about 26 % and was inhibitory to the methanogens. Results also showed that mesophilic bacteria could be adapted to a TAN concentration of about 5000 mg/L at pH 7.5 through gradual TAN loading. Similar results were obtained on effect of ammonia on AD of OFMSW mixed with real landfill leachate to simulate an anaerobic bioreactor landfill. CBP reduced as the TAN concentration increased. Compared with control reactors, reactors containing 7500 mg/L TAN at pH 8.0 and pH 8.5 had 61 % and 80 % reduction in CBP. Likewise, reactors containing 10,000 mg/L TAN at pH 8.0 and pH 8.5 had 68 % and 85 % reduction in CBP, compared with control reactors. Study confirmed that pH influenced the toxicity and composition of Total Ammonia Nitrogen (TAN). At high pH (i.e. 8.5), FAN component of TAN was about 26 % and was inhibitory to the methanogens. Results also showed that mesophilic bacteria could be adapted to a TAN concentration of about 5000 mg/L at pH 7.5 through gradual TAN loading.

The production of municipal solid waste has continued to grow in recent years. In Italy, municipal solid waste production reaches about 29 million tons per year. The organic fraction of municipal solid waste (OFMSW), which accounts for 30-40% of the total waste, usually undergoes biological treatments such as anaerobic digestion or composting, or is incinerated or landfilled. Biological treatments are considered not economically viable due to the long processing time (20-30 days), while incineration and landfilling are considered as low cost but polluting processes. In contrast, Hydrothermal Carbonization (HTC) is a cost-effective process to treat organic waste especially for the shorter processing time (0.5-8 h) and the possibility to treat directly wet heterogeneous materials. This thesis aims to investigate the potential use of HTC to upgrade OFMSW and other biomasses to biofuels or valuable byproducts. Chapter 1 gives an overview on the state of the art of HTC technology applied to organic wastes, focusing both on mechanisms and on the characteristics of reaction products. Chapter 2 investigates the potential use of HTC to upgrade the organic fraction of municipal solid waste (OFMSW) into biofuel and byproducts. The impact of process conditions (process time, temperature and solid load) on the formation, chemical and energy properties of hydrochar was deeply investigated. To analyze the behavior of hydrochar as a solid biofuel, the combustion (oxidation) of hydrochar and the co-firing (co-oxidation) of hydrochars and coals was also investigated. The results show that, especially at HTC harsher conditions, hydrochar is a “coal-like” material, that can be used as a valuable solid biofuel. The results evidenced that hydrochar is composed of primary char and secondary char. Primary char (non-extractable with organic solvents) has characteristics similar to coal and could be recovered for combustion, while secondary char is an amorphous and more volatile solid, easily extracted with organic solvents, which found possible application as a source of biochemicals and liquid bio-fuel. Chapter 3 investigates the use of HTC as a promising pre-treatment to enhance the biomethane potential during anaerobic digestion of OFMSW. Anaerobic digestion experiments were carried out using the HTC process liquid and the entire HTC reaction mixtures. Results proved that, when compared to the raw OFMSW, the use of HTC liquid and HTC mixture into AD lead to an increase of biomethane production of up to 37% and 363% by volume, respectively. Chapter 4 reports an HTC kinetics study and a kinetic model, which accounted for reactions leading to the production of primary and secondary char, as well as the liquid and gas phases. The model was optimized using experimental data performed on a lignocellulosic feedstock (olive trimmings) and validated on two other types of biomasses (grape marc and Opuntia Ficus Indica) and was used as a reliable tool to predict the carbon distribution among HTC products. In this chapter an in-depth analysis was also carried out to understand the evolution of feedstock characteristics during the heat-up transient phase before reaching the HTC set-point temperature. The results show that during heat up, the feedstock carbonized to a considerable extent at 220-250 °C. Tests clearly show evidence of the transition between thermal hydrolysis and HTC. Chapter 5 presents a study conducted to evaluate the economic feasibility and the detailed energy and cost analyses of a hypothetical HTC plant transforming wet biomass into pelletized dry hydrochar. To achieve these goals, a model was developed on the basis of experimental results obtained previously on two other organic materials (grape marc and off-specification compost). The results show that, when operating the HTC plant with grape marc at the optimal HTC conditions (T=220 °C, t=1 h, dry biomass to water ratio=0.19), the production cost of hydrochar were determined to be 157 €/ton, competitive with the price of wood pellets (150-200 €/ton). This makes HTC a promising process for a large development at the industrial scale.

The UK buries about 100 million tonnes of waste a year, of which 25% is municipal solid waste (refuse). The environmental impacts from gas and leachate releases are known and direct risks to health from landfill are reported. Europe has agreed to a Landfill Directive which has set targets for the stepwise reduction in biodegradable municipal waste going to landfill. The anaerobic digestion of municipal solid waste in controlled bioreactors is an area that could play an important role in overall evolution towards sustainability by recovering biogas and organic matter. Separated hydrolysis and subsequent anaerobic codigestion was demonstrated from the literature review to have the best potential for biodegradable municipal waste diverted from landfill. The rate of hydrolysis of solids wastes remains an outstanding problem. In this research, firstly the codigestion of industrial effluent (coffee wastewater), food wastes and garden wastes were investigated for their impact on hydrolysis and digestion. The results show that there were no treatability problems for coffee wastes up to 37.5% of volume feed per day at the HRT of 9 days. The results supported the view that dilute biodegradable streams such as coffee waste may improve digestion by promoting mixing. Fruit and vegetable wastes were highly biodegradable and can have a major improvement in biogas production of the whole codigestion process, whereas garden waste was not as successful as a cosubstrate, probably because of the predominant celluloses and lignocelluloses with a low biodegradability. The literature review also revealed that washing or elutriation can remove organic matter from municipal waste. This is an important hydrolytic process in which a solubilised acidic organic matter is obtained. The codigestion of refuse hydrolysate with sewage sludge was therefore studied. A control digester treating sewage sludge only was compared with an experimental reactor fed mixed refuse hydrolysate with sewage sludge. It was possible to add the solubilised hydrolysate to existing anaerobic digesters designed at a standard sludge solids loading rate without causing overloading. (Continues...).

O tratamento de resíduos sólidos orgânicos, como lodos de estação de tratamento de esgotos e a fração orgânica de resíduos sólidos urbanos, são desafios atuais da engenharia sanitária e ambiental. Os processos biológicos são os mais apropriados para o tratamento desses resíduos. Acordos recentes como o Protocolo de Kyoto e os mecanismos de desenvolvimento limpo (MDL) estão contribuindo para o crescimento da digestão anaeróbia de resíduos sólidos orgânicos em todo o mundo. Nesta pesquisa foi investigado o efeito da adição de lodo anaeróbio ao lixiviado de aterro sanitário empregado como inóculo de reator anaeróbio híbrido sólido-líquido tratando a fração orgânica de resíduos sólidos urbanos. Foi verificado que a adição de lodo melhorou a digestão anaeróbia, acelerando a degradação de ácidos graxos voláteis, antecipando a geração de biogás, aumentando a composição percentual de metano e promovendo maior variabilidade e presença de microrganismos. A adição de lodo também aumentou a eficiência de conversão de sólidos totais e sólidos totais voláteis e sólidos totais fixos / Treatment of organic solid wastes like wastewater treatment plant sludges and organic fraction of municipal solid wastes are current issues in environmental engineering. Biological processes are more appropriate to treat these wastes. Recent trends like Kyoto protocol and clean development mechanisms (CDM) are improving anaerobic digestion of organic solid wastes. It was investigated the effect of adding anaerobic sludge to bioreactor landfill leachate applied like seed in hybrid anaerobic solid-liquid bioreactor treating organic fraction of municipal solid wastes. It was verified that sludge addition improved anaerobic digestion, accelerating volatile fatty acids degradation, anticipating biogas generation, increasing methane percentile composition and promoting more variability and presence of microorganisms. Sludge addition also increased total solids, total volatile solids and total fixed solids conversion

O tratamento de resíduos sólidos orgânicos, como lodos de estação de tratamento de esgotos e a fração orgânica de resíduos sólidos urbanos, são desafios atuais da engenharia sanitária e ambiental. Os processos biológicos são os mais apropriados para o tratamento desses resíduos. Acordos recentes como o Protocolo de Kyoto e os mecanismos de desenvolvimento limpo (MDL) estão contribuindo para o crescimento da digestão anaeróbia de resíduos sólidos orgânicos em todo o mundo. Nesta pesquisa foi investigado o efeito da adição de lodo anaeróbio ao lixiviado de aterro sanitário empregado como inóculo de reator anaeróbio híbrido sólido-líquido tratando a fração orgânica de resíduos sólidos urbanos. Foi verificado que a adição de lodo melhorou a digestão anaeróbia, acelerando a degradação de ácidos graxos voláteis, antecipando a geração de biogás, aumentando a composição percentual de metano e promovendo maior variabilidade e presença de microrganismos. A adição de lodo também aumentou a eficiência de conversão de sólidos totais e sólidos totais voláteis e sólidos totais fixos / Treatment of organic solid wastes like wastewater treatment plant sludges and organic fraction of municipal solid wastes are current issues in environmental engineering. Biological processes are more appropriate to treat these wastes. Recent trends like Kyoto protocol and clean development mechanisms (CDM) are improving anaerobic digestion of organic solid wastes. It was investigated the effect of adding anaerobic sludge to bioreactor landfill leachate applied like seed in hybrid anaerobic solid-liquid bioreactor treating organic fraction of municipal solid wastes. It was verified that sludge addition improved anaerobic digestion, accelerating volatile fatty acids degradation, anticipating biogas generation, increasing methane percentile composition and promoting more variability and presence of microorganisms. Sludge addition also increased total solids, total volatile solids and total fixed solids conversion

This study was carried out to evaluate the potential of high-rate anaerobic digestion of high-solids organic fraction of municipal solid waste (OFMSW) for the production of organic acids and alcohols in leaching bed reactors (LBRs). For this purpose, two different experimental set-ups, namely Set-1 and Set-2, were operated. In the Set-1, only OFMSW without paper was studied in two identical LBRs, whereas, four identical LBRs, fed with OFMSW with paper and cow manure in different proportions, were operated in the Set-2. In this study, 50-60% of hydrolysis efficiency was achieved in the LBRs of Set-1, whereas this value was decreased to 20-25% in the LBRs of Set-2 / which was resulted from OFMSW containing cellulose and less volume of water addition in the Set-2. The mass of total volatile fatty acids (tVFA) production was found as 7000-9000 mg at the end of 80 days in the LBRs of Set-1, fed with OFMSW without paper, whereas it was 3000 mg at the end of 40 days in the LBR of Set-2, containing only OFMSW with paper. It was also observed that cow manure addition increased the amount of tVFA production in the LBR of Set-2. In conclusion, LBRs were found as alternative reactors for the degradation of OFMSW compared to completely stirred tank reactors (CSTRs) in terms of rapid hydrolysis and acidification, which can result in high hydrolysis yield and tVFA production.

The National Solid Waste Policy recommends that, in adequate final disposal, only unserviceable waste should be released, which it is not the case of organic waste that accounts more than half of the municipal solid waste generation in the country. In this context, this research aimed to develop a proposal for a selective collection of the organic fraction of household solid waste (OFHSW) in Pici neighborhood, Fortaleza-CE, aiming its use for the generation of biogas from the anaerobic digestion. This research occurred in 05 (five) steps, namely: the development of the environmental education (EE) program; physical characterization of household solid waste (HSW); the implementation of a selective collection program of OFHSW; the physical and chemical characterization of OFHSW; and the anaerobic biodegradability tests. Initially, a socio-environmental questionnaire was applied to a total of 175 residences, in which most of its residents presented favorable socioeconomic characteristics for the development of this project. The HSW sampled showed a high average of per capita generation (0.93 Kg/hab.dia), low apparent specific weight (average of 156 Kg/mÂ) and high percentage of organic matter (average of 55.9%). In regard to the participation in the selective collection program, there was a potential participation of 61% of the residences, from which 33% effectively donated a clean OFHSW. The OFHSW showed slightly acidic characteristics, consisting of 74% moisture and 26% of TS, being basically composed of putrescible organic matter (VS = 92.15% TS on average) and rich in nutrients (average of TP= 0.68% and TKN = 1.43%). In biodegradability tests to analyze the effect of operating conditions, better results were found of SMA, biogas production and composition and COD removal in the flasks incubated at a speed of 150 rpm and with addition of 1 g/L of alkalizing. The pretreatment type that provided a higher biodegradability of OFHSW was the thermal one, in which the matter was exposed to a 30 minutes process of autoclaving, where were identified the largest removals of VS (41% removed), COD (56% removed) and value of SMA (1.0777 gCOD-CH4/gVS.d). It is also emphasized that in all the biodegradability tests, about 60% or more of the biogas composition was methane. It was observed that EE actions were able to provide a representative participation of the population in the OFHSW segregation / A PolÃtica Nacional de ResÃduos SÃlidos preconiza que na disposiÃÃo final adequada somente os rejeitos devem ser lanÃados, nÃo sendo o caso dos resÃduos orgÃnicos, que constituem mais da metade dos resÃduos sÃlidos urbanos gerados no paÃs. Diante desse contexto, esta pesquisa teve como principal objetivo desenvolver uma proposta de coleta seletiva da fraÃÃo orgÃnica dos resÃduos sÃlidos domiciliares (FORSD) no bairro Pici, Fortaleza-CE, visando sua utilizaÃÃo para a geraÃÃo de biogÃs a partir da biodigestÃo anaerÃbia. Esta pesquisa ocorreu em 05 (cinco) etapas, sendo elas: o desenvolvimento do programa de educaÃÃo ambiental (EA); a caracterizaÃÃo fÃsica dos resÃduos sÃlidos domiciliares (RSD); a implantaÃÃo do programa de coleta seletiva da FORSD; a caracterizaÃÃo fÃsica e quÃmica da FORSD; e, os ensaios de biodegradabilidade anaerÃbia. Inicialmente, aplicou-se questionÃrio socioambiental, abordando-se um total de 175 residÃncias, com um pÃblico que possuiu, em sua maioria, caracterÃsticas socioeconÃmicas favorÃveis ao desenvolvimento deste projeto. O RSD amostrado apresentou uma geraÃÃo per capita mÃdia elevada (0,93 Kg/hab.dia), baixo peso especÃfico aparente (156 Kg/mÂ, em mÃdia) e percentual de matÃria orgÃnica elevada (mÃdia de 55,9%). Quanto à participaÃÃo no programa de coleta seletiva, registrou-se uma participaÃÃo em potencial de 61% das residÃncias e com 33% doando efetivamente a FORSD limpa. A FORSD apresentou caracterÃsticas ligeiramente Ãcidas, constituÃda de 74% de umidade e 26% de ST, sendo basicamente composta por matÃria orgÃnica putrescÃvel (STV = 92,15% dos ST, em mÃdia) e rica em nutrientes (mÃdia de PT = 0,68% e de NTK = 1,43%). Nos ensaios de biodegradabilidade, para anÃlise da influÃncia das condiÃÃes operacionais, foram encontrados melhores resultados de AME, produÃÃo e composiÃÃo de biogÃs e remoÃÃo de DQO nos frascos incubados a uma rotaÃÃo de 150 rpm e com adiÃÃo de 1g/L de alcalinizante. O tipo de prÃ-tratamento que proporcionou maior biodegradabilidade da FORSD foi o tÃrmico submetido a 30 minutos no processo de autoclavagem, em que foram registrados as maiores remoÃÃes de STV (41% removido), DQO (56% removida) e valor de AME (1,0777 gDQO-CH4/gSTV.d). Ressalta-se tambÃm que nos ensaios de biodegradabilidade cerca de 60% ou mais da composiÃÃo do biogÃs era gÃs metano. Observou-se que as aÃÃes de EA proporcionaram uma participaÃÃo representativa da populaÃÃo na segregaÃÃo da FORSD.

Orientadora: Profa. Dra. Juliana Tófano de Campos Leite Toneli / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, Santo Amdré, 2017. / A limitação das fontes não renováveis de energia tem propiciado o desenvolvimento e o aprimoramento de tecnologias de conversão energética a partir de fontes renováveis. Neste cenário de necessidade de diversificação da matriz energética brasileira, a biomassa apresenta potencial elevado de produção, sobretudo no que diz respeito aos Resíduos Sólidos Urbanos. Este trabalho teve como objetivo o estudo do potencial de produção de biometano a partir de composições de fração orgânica de Resíduos Sólidos Urbanos do município de Santo André por meio do processo de biodigestão anaeróbia em um biodigestor em batelada do tipo Automatic Methane Potential Test System (AMPTS II). O estudo foi realizado para amostras da fração orgânica de resíduos oriundos de diferentes setores domiciliares do município de Santo André (Composição A : setores da região central/comercial ; Composição B : setores da região residencial/urbana ; Composição C : setores da região industrial/suburbana), da Companhia Regional de Abastecimento Integrado de Santo André (CRAISA) e de feiras livres. Os resultados obtidos ao longo deste trabalho foram comparados e relacionados. Os valores médios obtidos foram : o teor de umidade para todas as composições foi superior a 55% : A (55,85 ± 15,41)% , B(63,80 ± 2,36)% e C(67,94 ± 7,29)%, Feiras (71,88 ± 14,70)% e CRAISAS (81,61 ± 2,18)% e o teor de sólidos voláteis foi superior a 64% : A (64,78 ± 1,49)% , B(79,26 ± 0,89)% e C(72,60 ± 1,61)%, Feiras (87,66 ± 1,79)% e CRAISAS (84,38 ± 0,78)%. De acordo com a razão C/N obtida, as composições formadas pela fração orgânica da CRAISA e dos setores centrais/comerciais apresentaram, respectivamente, valores dentro da faixa ideal (20<C/N<30), 27,9 e 25,6. Da composição centesimal, o teor de lipídios variou de 2,07 a 5,62%, o teor médio de carboidratosfoi de 85,81% e o teor de proteínas apresentou valor médio de (10,28 ± 2,86)%. O potencial teórico de produção de metano das frações orgânicas do RSU com base na composição elementar variou entre 376,83 ml de CH4/g de SV (composição CRAISA) e 699,46 ml de CH4/g de SV (Composição A) e com base na composição centesimal, entre 435,45 ml de CH4/g de SV (composição CRAISA) e 457,12 ml de CH4/g de SV (composição C). As composições que apresentam maior produção de metano experimentalmente foram as composições B(203,31 ml de CH4/g de SV) e a composição A (264,83 ml de CH4/g de SV). / The limitation of non-renewable sources of energy has led to the development and improvement of energy conversion technologies from renewable sources. In this scenario of the need for diversification of the Brazilian energy matrix, biomass presents a high production potential, especially with regard to Municipal Solid Waste. The objective of this work was to study the potential of biomethane production from organic fractions of municipal solid waste in the municipality of Santo André by means of the anaerobic biodigestion process in a batch biodigestor of the Automatic Methane Potential Test System (AMPTS II). The study was carried out for samples of the organic fraction of residues from different domiciliary sectors of the municipality of Santo André (Composition A: sectors of the central/commercial region; Composition B: sectors of the residential/urban region; Composition C: industrial/ uburban region), of the Regional Company of Integrated Supply of Santo André (CRAISA) and of free markets. The results obtained during this work were compared and related. The mean values obtained were: moisture content for all compositions was higher than 55%: A (55,85 ± 15,41)%, B (63,80 ± 2,36)% and C (67,94 ± 7,29)%, Free Markets (71,88 ± 14,70)% and CRAISAS (81,61 ± 2,18)% and the volatile solids content was greater than 64%: A (64,78 ± 1,49 )%, B (79,26 ± 0,89)% and C (72,60 ± 1,61)%, Free Markets (87,66 ± 1,79)% and CRAISAS (84,38 ± 0,78)% . According to the obtained C/N ratio, the compositions formed by the organic fraction of the CRAISA and of the central/commercial sectors presented, respectively, values within the ideal range (20<C/N<30), 27,9 and 25,6. From the centesimal composition, the lipid content varied from 2,07 to 5,62%, the average carbohydrate content was 85,81% and the protein content presented an average value of (10,28 ± 2,86)%. The theoretical methane production potential of the RSU organic fractions based on the elemental composition ranged from 376,83 ml CH4/g of SV (composition CRAISA) to 699,46 ml CH4/g of SV (Composition A) and based on the centesimal composition, between 435,45 ml of CH4/g of SV (composition CRAISA) and 457,12 ml of CH4/g of SV (composition C). The compositions having the highest methane production experimentally were compositions B (203,31 ml of CH4/g of SV) and composition A (264,83 ml of CH4/g of SV).

The aim of the diploma thesis was to optimize the sequential fractionation method of organic matter to be used for physico-chemical characterization of extracted fractions. Humic acid isolated from oxidized brown coal of Leonardite was used as a source matrix of organic matter. An eluotropic series was assembled and sequential fractionation was performed by extraction on a Soxhlet apparatus. The original humic acid and fractions were characterized by elemental analysis (EA) and thermogravimetric analysis (TGA), followed by Fourier transform infrared spectrometry (FTIR), molecular absorption spectrometry (UV/VIS), fluorescence spectrometry and potentiometric titration. Atomic ratios were determined from the results of the elemental analysis. From the measured UV/Vis and fluorescence excitation and emission spectra, the absorption coefficients, resp. fluorescence coefficients. Used fractionation method proved to be a suitable method for studying HA structure. A total of 62 wt. % of initial materiál was extracted, indiivdual fraction amounted from 0.36–30.92 wt. %. From the results of the structural analysis, it is clear that with increasing polarity of the organic solvent, fractions with long aliphatic chains were first isolated and their aromaticity graddualy increased. Non-polar organic solvents were suitable for the extraction of lipid-like coumpounds, while the most polar organic fractions were rich in polar groups and their structual parameters were close to the original humic acid. The fraction extracted with acetonitrile was the most unique fraction. This fraction was rich on nitrogen and amine groups and was similar to protein-like structures. In the last two fractions, extracted with alcohols, a significant bathochromic shift typical of fluorophore type V was observed. Among other things, they were also characterized by a higher content of plant carbohydrate residues.