Дисертації з теми "Digestion of lignocellulosic biomass"
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Liew, Lo Niee. "Solid-state Anaerobic Digestion of Lignocellulosic Biomass for Biogas Production." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306870552.
Повний текст джерелаLin, Long. "Technical, Microbial, and Economic Study on Thermophilic Solid-state Anaerobic Digestion of Lignocellulosic Biomass." The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1500505570855855.
Повний текст джерелаBrown, Dan Lee. "Comparison of Solid-State to Liquid Phase Anaerobic Digestion of Lignocellulosic Biomass for Biogas Production." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1341870854.
Повний текст джерелаXu, Fuqing. "Experimental Studies and Modeling of Solid-State Anaerobic Digestion for Enhanced Methane Production from Lignocellulosic Biomass." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1406143408.
Повний текст джерелаKumi, Philemon James. "Improving the bioconversion of lignocellulosic feedstock to bio-fuels and chemicals." Thesis, University of South Wales, 2015. https://pure.southwales.ac.uk/en/studentthesis/improving-the-bioconversion-of-lignocellulosic-feedstock-to-biofuels-and-chemicals(7088d092-fb93-4d70-ba3d-1abb233e33e3).html.
Повний текст джерелаMancini, Gabriele. "Different approaches to enhance the biogas production from the anaerobic digestion of lignocellulosic materials." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1250/document.
Повний текст джерелаBiogas production via anaerobic digestion (AD) is a long-standing renewable technology and a continuously growing bioprocess worldwide. Lignocellulosic materials (LMs) present several features that make them especially attractive among the organic substrates commonly employed in anaerobic bioreactors. In particular, LMs under the form of agricultural residues have been acknowledged as the most suitable feedstock for biomethane production due to their high availability, low cost, sustainability and no direct competition with food and feed production. However, their recalcitrance to biological conversion hinders their application for full-scale production of biogas and requires a pretreatment step to improve the LM microbial degradability. In addition to the challenges posed by the lignocellulosic structure, the supply of trace elements (TEs) has often been found insufficient within biogas digesters. The microbial growth depends on the availability and optimal amount of several specific TEs, which are essential constituents of cofactors in enzyme systems involved in the biochemistry of methane formation. Different chemical pretreatments, namely the solvent N-methylmorpholine-N-oxide (NMMO), the organosolv process, and an alkaline pretreatment using NaOH, were investigated during several batch experiments to enhance the biogas production yields from different LMs (i.e. rice straw, hazelnut skin, cocoa bean shell and wheat straw). Changes in the cellulose crystallinity, water retention value and chemical composition were assessed to better evaluate the effect of the different pretreatments studied on the lignocellulosic structure. Furthermore, the addition of different doses of Fe, Co, Ni and Se on the AD of rice straw was studied, evaluating the influence of the inoculum origin, as well as the performance and synergistic effect of combining an alkaline pretreatment with the addition of trace elements prior to the AD of rice straw. The bioavailability of TEs during batch biomethane potential tests was also evaluated applying a sequential extraction technique. The three pretreatments investigated were effective methods for enhancing the biomethane production from the employed LMs. The biomethane yield from the AD of rice straw increased by 82 and 41% after the NMMO and organosolv pretreatment, respectively. When compared within the same experiment, the NMMO, organosolv and NaOH pretreatment were able to improve the AD of wheat straw, differently affecting the chemical composition of the raw LM. The cumulative biomethane production yield of 274 mL CH4/g VS obtained with the untreated wheat straw was enhanced by 11% by the NMMO pretreatment and by 15% by both the organosolv and alkaline pretreatment. Hazelnut skin and cocoa bean shell, which were never investigated before as AD substrates, showed a good potential for biogas production, with cumulative biomethane yields of 223-261 and 199-231 mL CH4/g VS, respectively, for the untreated feedstocks. However, both NMMO and organosolv pretreatments did not lead to a significant enhancement of the biomethane production yields from these two LMs. The TE supplementation had only a minor effect compared to the pretreatment methods. The addition of Fe, Co, Ni and Se did not result in a significant improvement of the AD of rice straw, whereas the use of the NaOH pretreatment, during the same batch experiment, caused a considerable enhancement of the AD, increasing the biogas production yield by 21%. The negligible effect observed after TE supplementation on the AD of rice straw could be linked to its complex lignocellulosic structure, which requires an enhancement of the hydrolysis, which, rather than the methanogenesis, is the rate-limiting step
Thomas, Hélène. "Etude de l'impact des pré-traitements alcalins sur la digestion anaérobie du sorgho et du miscanthus." Electronic Thesis or Diss., Montpellier, SupAgro, 2019. http://www.theses.fr/2019NSAM0011.
Повний текст джерелаIn the context of global warming and declining fossil fuel reserves, lignocellulosic biomass can provide a renewable source of energy, materials and chemicals. In particular, biogas production by anaerobic digestion is facing a fast development. This thesis project takes place in this biorefinery concept. Two different lignocellulosic biomasses, which present the advantage of combining high biomass production potential with minimal environmental impact, were studied. For this kind of biomass, it is well known that lignin acts as a barrier to the accessibility of compounds. The objective of this thesis was to study the impact of alkaline pre-treatments, known be efficient in biomass delignification and thus improve its bioaccessibility and its degradation by anaerobic digestion. The study of the impact of these pre-treatments on the biochemical composition of biomasses and their methane production showed that these impacts were different according the biomass and the operating conditions of the applied pre-treatments (reagent, duration, temperature, water content). With the aim of applying it in agricultural anaerobic co-digestion context, the impact of some of these pre-treatments of sorghum and miscanthus was studied in leach bed reactors. Sorghum was found to be an adequate co-substrate for manure. Finally, the original study of the mechanisms of action of these pre-treatments at the biomass anatomical structure scale showed that the pre-treatments act differently depending on the location and type of lignin. This thesis work therefore allows a better understanding of the impact of pre-treatments on different lignocellulosic biomasses
Silva, Vanessa Cristina da. "Obtenção anaeróbia de etanol em reator em batelada a partir de glicose, xilose e celulose em condição termófila." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/18/18138/tde-14082015-142835/.
Повний текст джерелаLignocellulosic biomass is an attractive alternative to increase biofuels proposal, as its composed of cellulose and hemicellulose. These polymers are consisted in individual molecules of glucose and xylose, through some thermophilic bacteria, can metabolize these carbohydrates in ethanol. Therefore, this study reports on using the principals carbon sources of lignocellulosic biomass (cellulose, glucose, and xylose), and producing ethanol through microbial consortium from anaerobic and thermophilic inoculum. The biomass was submitted to variation of pH (2,3,4,5,6, and 7) and two kinds of medium, due to ethanol production in batch reactors. For ethanol production, the optimized pH and medium were 7,0 and Thermoanaerobacter ethanolicus medium, respectively. The enriched culture was being cultivated in pH and medium experiments were used to ethanol production experiments that carried out in batch reactors, from cellulose, glucose and xylose were realized in triplicate and were maintained at 55 °C, in both batches had a control reactor (without these organics substrates). Positive results in ethanol yields were 1,73 mol ethanol/ mol glucose and 1,33 mol ethanol/ mol xylose. In celluloses reactors the microbial consortium was efficient in substrate degradation, however, was obtained lower ethanol yields (1,88 mol ethanol/ g cellulose). In control reactors from glucose, cellulose and xylose, that yeast extract was the unique organic source, ethanol production was 1,27 mmol/L, 0,39 mmol/L e 1,65 mmol/L, respectively. In all reactors were detected acetic, butyric and propionic acids. The acetic acid production was 5,73 mmol/L, 9,73 mmol/L e 14,45 mmol/L in glucose, cellulose and xylose reactors, respectively. For glucoses reactors were observed lower hydrogen production (0,31 mol hydrogen/ mol glucose), in the other reactors did not observed gases production. Instead of the following yields were obtained: 6,6 mmol methane/ g cellulose and 0,68 mol methane/ mol xylose. Taking this into account, microbial consortium enriched had characteristics to degrade cellulose and metabolize glucose and xylose to ethanol.
Pinilla, Maria Juliana. "Comparative Life Cycle Assessments of Lignocellulosic and Algae Biomass Conversion to Various Energy Products through Different Pathways." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3740.
Повний текст джерелаPuthumana, Amal Babu. "Effect of feed ratio and pre-treatment on methane yields during anaerobic co-digestion of sugarcane bagasse and trash with chicken manure." Thesis, Griffith University, 2020. http://hdl.handle.net/10072/393971.
Повний текст джерелаThesis (Masters)
Master of Philosophy (MPhil)
School of Eng & Built Env
Science, Environment, Engineering and Technology
Full Text
Liu, Xun. "Valorisation énergétique de la biomasse lignocellulosique par digestion anaérobie : Prétraitement fongique aérobie." Thesis, Lyon, INSA, 2015. http://www.theses.fr/2015ISAL0099/document.
Повний текст джерелаBioconversion to methane lignocellulosic biomass is one of the most promising alternatives for the production of methane from anaerobic digestion. However, lignocellulosic biomass has various bio-physicochemical characteristics due to their biochemical composition and diverse structural organization. Moreover, their low biodegradability in anaerobic condition requires pretreatment before methanation to optimize methane production. This work aims to evaluate the influence of the characteristics of a wide range of lignocellulosic substrates on their anaerobic biodegradability and correlations between their bio-physical-chemical characteristics and biomethane potential, and study the effects of fungal pretreatment in the presence of Ceriporiopsis subvermispora on the biogas potential of lignocellulosic biomass selected in this study and characterize their changes of their characteristics before and after the fungal pretreatment. The characterization of 36 representative lignocellulosic biomass of a wide range of potentially mobilized deposits allowed to highlight the linear correlations between biomethane potential of biomass and some of their bio-physical-chemical characteristics, of which the lignin content and biochemical oxygen demand. The forest and agricultural biomass exhibited distinct characteristics of the aerobic and anaerobic biodegradability. The results of fungal pretreatment of the 5 biomass indicated that the white rot fungus Ceriporiopsis subvermispora reacts distinctly depending on the pretreated biomass. For some biomass, fungal pretreatment leads to significant increase of methane production and the bioconversion rate of methane. This species presents the ability to selectively degrade lignin on some biomasses, in others, the ability to non-selectively degrade polysaccharides and lignins. In addition, for both strains of Ceriporiopsis subvermispora tested, different metabolisms were highlighted on the same biomass. The results of compositions and those of the structural analysis of biomass (initials, autoclaved, controls, and pretreated with Ceriporiopsis subvermispora) showed that their structure can be modified without observing a significant transformation of their biochemical composition
Girisuta, Buana. "Levulinic acid from lignocellulosic biomass." [S.l. : Groningen : s.n. ; University Library Groningen] [Host], 2007. http://irs.ub.rug.nl/ppn/304751316.
Повний текст джерелаBrandt, Agnieszka. "Ionic liquid pretreatment of lignocellulosic biomass." Thesis, Imperial College London, 2012. http://hdl.handle.net/10044/1/9166.
Повний текст джерелаSamad, Abdul. "SOPHOROLIPID PRODUCTION FROM LIGNOCELLULOSIC BIOMASS FEEDSTOCKs." OpenSIUC, 2015. https://opensiuc.lib.siu.edu/theses/1799.
Повний текст джерелаBorén, Eleonora. "Off-gassing from thermally treated lignocellulosic biomass." Doctoral thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-141921.
Повний текст джерелаCorredor, Deisy Y. "Pretreatment and enzymatic hydrolysis of lignocellulosic biomass." Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/693.
Повний текст джерелаHåseth, Jenny Kristin. "Decrystallization of Lignocellulosic Biomass using Ionic Liquids." Thesis, Norges Teknisk-Naturvitenskaplige Universitet, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-21106.
Повний текст джерелаFrazão, Cláudio José Remédios. "Challenges of ethanol production from lignocellulosic biomass." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13657.
Повний текст джерелаThe present work aimed to tackle two of the major challenges in bioethanol production from lignocellulosic feedstocks: (i) high tolerance of microorganisms to lignocellulosic inhibitors, and (ii) microbial contamination avoidance. Lignocellulosic inhibitors are an important fraction of spent sulphite liquor (SSL), a by-product of the pulp and paper industries. Hardwood SSL (HSSL) is rich in pentose sugars, mainly xylose, which can be converted to ethanol by the yeast Scheffersomyces stipitis. In this work, a population of S. stipitis previously adapted to 60 % (v/v) of HSSL was used, and its stability on the absence of inhibitors during ten sequential transfers was investigated at single-clone level. During the screening trials, all the isolated clones showed higher xylose and acetate uptake rates and lower ethanol productivities than the parental strain. The clone exhibiting higher xylose uptake rate (0.558 g L-1 h-1) was named isolate C4. The effect of short-term adaptation on isolate C4 fermentation performance was evaluated by pre-cultivating the clone in the presence or absence of 60 % (v/v) of HSSL. The uptake rates of glucose and xylose were similar under both conditions, but a higher acetate consumption rate (0.101 g L-1 h-1) and maximum ethanol concentration (4.51 g L-1) were achieved without pre-adaptation step, suggesting the robustness of isolate C4. The industrial bioethanol production is mostly carried out under non-sterile conditions, which favours microbial contamination. In this work, the mechanism that triggers Lactobacillus pentosus contamination in SSL plants was investigated. A simulated synthetic hydrolysate mimicking the average composition of sugars and inhibitors of softwood SSL (SSSL) was used and the impact of different factors in bacterial and Saccharomyces cerevisiae viability was analysed. The presence of yeast extract led to an increase in lactate production (9-fold higher) and L. pentosus viability when only bacteria was inoculated. Using different inoculation ratios of yeast/bacteria, the ethanol production rates were not affected after 48 h, and L. pentosus failed to overtake S. cerevisiae. The presence of inhibitors delayed yeast growth, but the bacteria did not outcompete S. cerevisiae. When the pH was optimal to L. pentosus in co-culture experiments, the bacterial cell viability decreased slower. The results indicate that L. pentosus was unable to overtake S. cerevisiae. The presence of yeast extract and favourable pH to bacteria are important factors that can play a role in the mechanism that triggers the bacterial contamination in ethanol plants.
A presente dissertação tem como objetivo abordar dois dos maiores desafios na produção de bioetanol a partir de biomassa lenhocelulósica: (i) elevada tolerância de microrganismos a inibidores, e (ii) prevenção de contaminação microbiana. Os inibidores lenhocelulósicos são uma fração relevante do licor de cozimento ao sulfito ácido (SSL), um subproduto das indústrias do papel e pastas. O SSL de folhosas (HSSL) é rico em pentoses, principalmente xilose, que podem ser fermentadas em etanol pela levedura Scheffersomyces stipitis. Neste estudo, utilizou-se uma população de S. stipitis previamente adaptada a 60 % (v/v) HSSL, e avaliou-se a sua estabilidade na ausência de inibidores durante dez transferências sequenciais. Comparando com a estirpe original, todos os clones isolados exibiram taxas de consumo de xilose e ácido acético superiores e produtividades em etanol inferiores. O clone que demonstrou a maior taxa de consumo de xilose (0,558 g L-1 h-1) foi designado isolado C4, e o efeito de adaptação de curta duração no seu desempenho fermentativo foi investigado através do seu pré-cultivo na presença ou ausência de 60 % (v/v) HSSL. Nas duas condições, as taxas de consumo de glucose e xilose foram idênticas, contudo, atingiu-se maior taxa de consumo de ácido acético (0,101 g L-1 h-1) e maior concentração máxima de etanol (4,51 g L-1) foram atingidas na ausência do processo de adaptação de curta duração. Tais resultados demonstram a robustez do isolado C4. A maioria dos processos de produção industrial de bioetanol é realizada na ausência de esterilidade, favorencendo a contaminação por microrganismos. Neste estudo, investigou-se o mecanismo responsável pela contaminação com Lactobacillus pentosus na indústria de SSL. Para tal, utilizou-se um hidrolisado sintético mimetizando a composição média de açúcares e inibidores de SSL de resinosas (SSSL) e averiguou-se o impacto de vários fatores na viabilidade de L. pentosus e S. cerevisiae. A presença de extrato de levedura foi responsável pelo aumento da produção de ácido lático (9 vezes) e da viabilidade bacteriana quando L. pentosus foi cultivado na ausência de levedura. Diferentes proporções de inóculo de levedura/bactéria não afetaram a produção de etanol após 48 h de fermentação, e L. pentosus foi incapaz de ser a estirpe dominante durante os ensaios de co-cultura. A presença de inibidores retardou o crescimento da levedura, mas a bactéria foi de novo incapaz de se a espécie dominante. Ajustando o valor de pH para o ótimo de L. pentosus nos ensaios de co-cultura, a viabilidade celular da bactéria diminuiu mais lentamente. Os resultados demonstram que L. pentosus não foi a espécie dominante nos ensaios de co-cultura. A presença de extrato de levedura e de valores de pH favoráveis a L. pentosus podem desempenhar um papel importante no mecanismo responsável pela contaminação bacteriana nas indústrias de produção de bioetanol.
Luccarini, Cristina. "Studio sperimentale dell'effetto di pretrattamenti termici, fisici e chimici sulla digestione anaerobica di biomasse lignocellulosiche." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
Знайти повний текст джерелаGan, Jing. "Hydrothermal conversion of lignocellulosic biomass to bio-oils." Diss., Kansas State University, 2012. http://hdl.handle.net/2097/13768.
Повний текст джерелаDepartment of Biological and Agricultural Engineering
Wenqiao Yuan
Donghai Wang
Corncobs were used as the feedstock to investigate the effect of operating conditions and crude glycerol (solvent) on bio-oil production. The highest bio-oil yield of 33.8% on the basis of biomass dry weight was obtained at 305°C, 20 min retention time, 10% biomass content, 0.5% catalyst loading. At selected conditions, bio-oil yield based on the total weight of corn cobs and crude glycerol increased to 36.3% as the crude glycerol/corn cobs ratio increased to 5. Furthermore, the optimization of operating conditions was conducted via response surface methodology. A maximum bio-oil yield of 41.3% was obtained at 280°C, 12min, 21% biomass content, and 1.56% catalyst loading. A highest bio-oil carbon content of 74.8% was produced at 340°C with 9% biomass content. A maximum carbon recovery of 25.2% was observed at 280°C, 12min, 21% biomass content, and 1.03% catalyst loading. The effect of biomass ecotype and planting location on bio-oil production were studied on big bluestems. Significant differences were found in the yield and elemental composition of bio-oils produced from big bluestem of different ecotypes and/or planting locations. Generally, the IL ecotype and the Carbondale, IL and Manhattan, KS planting locations gave higher bio-oil yield, which can be attributed to the higher total cellulose and hemicellulose content and/or the higher carbon but lower oxygen contents in these feedstocks. Bio-oil from the IL ecotype also had the highest carbon and lowest oxygen contents, which were not affected by the planting location. In order to better understand the mechanisms of hydrothermal conversion, the interaction effects between cellulose, hemicellulose and lignin in hydrothermal conversion were studied. Positive interaction between cellulose and lignin, but negative interaction between cellulose and hemicellulose were observed. No significant interaction was found between hemicelluose and lignin. Hydrothermal conversion of corncobs, big bluestems, switchgrass, cherry, pecan, pine, hazelnut shell, and their model biomass also were conducted. Bio-oil yield increased as real biomass cellulose and hemicellulose content increased, but an opposite trend was observed for low lignin content model biomass.
Lopes, André Miguel da Costa. "Pre-treatment of lignocellulosic biomass with ionic liquids." Master's thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/9521.
Повний текст джерелаO objetivo deste trabalho foi estudar o pré-tratamento de biomassa lignocelulósica, como a palha de trigo, usando líquidos iónicos (LIs) de modo a obter a separação dos principais componentes, nomeadamente, celulose, hemicelulose e lignina. O processo de pré-tratamento foi otimizado com base em duas metodologias descritas na literatura utilizando o líquido iónico acetato de 1-etil-3-metilimidazólio ([emim][CH3COO]). A metodologia otimizada permitiu separar as frações ricas em hidratos de carbono das frações de lignina, ambas com elevada pureza, e com uma recuperação de LIs até um máximo de 97% da sua massa inicial. Desta forma, o LI pode ser reusado confirmando a flexibilidade do processo desenvolvido. A versatilidade do método foi testada com a investigação de três líquidos iónicos diferentes, nomeadamente hidrogenossulfato de 1-butil-3-metilimidazólio ([bmim][HSO4]), tiocianato de 1-butil-3-metilimidazólio ([bmim][SCN]) e dicianamida de 1-butil-3-metilimidazólio ([bmim][N(CN)2]). No processo de dissolução de palha de trigo observou-se uma dissolução completa a nível macroscópico apenas para os líquidos iónicos [emim][CH3COO] e [bmim][HSO4]. O [emim][CH3COO] apresentou maior eficiência no processo de dissolução e regeneração da biomassa. Contrariamente, o [bmim][SCN] demonstrou ser o menos eficiente em todo o processo de pré-tratamento. Um comportamento diferente foi observado para o [bmim][HSO4], cujo pré-tratamento apresentou similaridades a uma hidrólise ácida. Os pré-tratamentos com [bmim][HSO4] e [bmim][N(CN)2] permitiram a obtenção de frações ricas em celulose com um conteúdo em hidratos de carbono de 87 a 90%. Para as frações ricas em celulose provenientes do pré-tratamento com [emim][CH3COO] foram efetuados ensaios de hidrólise enzimática para verificar a potencial aplicação destas frações, bem como, avaliar a eficiência das metodologias de pré-tratamento estudadas. Os resultados obtidos demonstraram elevado índice de digestibilidade da celulose e confirmou o elevado teor de glucose presente na fração celulósica obtida pela metodologia otimizada. A técnica de Espectroscopia de Infravermelho com Transformadas de Fourier (FT-IR) permitiu efetuar análises qualitativas e quantitativas de todas as amostras obtidas nos pré-tratamentos realizados. Para avaliar a pureza dos LIs após os pré-tratamentos utilizou-se a técnica espectroscópica de ressonância magnética nuclear (RMN). Os resultados provenientes dos ensaios de hidrólise enzimática foram obtidos através da técnica cromatográfica de HPLC.
This work is devoted to the pre-treatment of lignocellulosic biomass using ionic liquids (ILs) to separate cellulose, hemicellulose and lignin fractions. Particularly, research was focused on studying the influence of various ILs on the pre-treatment of wheat straw. The pre-treatment procedure was optimised basing on two methodologies presented in the literature. In the optimised method 1-ethyl-3-methylimidazolium acetate ([emim][CH3COO]) IL was used. The developed method is beneficial as allows a separation of highly-purified carbohydrate and lignin-rich samples and permits to recover ILs with a yield of 97wt%. Therefore, the IL could be reused confirming a great flexibility of the developed method. Furthermore, versatility of the method was confirmed by examination of different ILs such as 1-butyl-3-methylimidazolium hydrogensulfate ([bmim][HSO4]), 1-butyl-3-methylimidazolium thiocyanate ([bmim][SCN]) and 1-butyl-3-methylimidazolium dicyanamide ([bmim][N(CN)2]). Only [emim][CH3COO] and [bmim][HSO4] ILs were found to be capable to achieve a macroscopic complete dissolution of wheat straw. Considering dissolution and regeneration process, [emim][CH3COO] was the most efficient among investigated ILs. On the contrary, [bmim][SCN] demonstrated the lowest efficiency either in dissolution and regeneration or fractionation processes. The [bmim][HSO4] showed different behaviour from other ILs exhibiting similarities to acid hydrolysis pre-treatment. Pre-treatments with [bmim][HSO4] and [bmim][N(CN)2] allowed to recover cellulose rich-samples with a carbohydrate content between 87 to 90wt%. In order to verify the potential further applicability of obtained carbohydrate-rich fractions as well as to evaluate the pre-treatment efficiency, the cellulose-rich fraction obtained from treatment with [emim][CH3COO] was applied for the enzymatic hydrolysis. Achieved results showed a high digestibility of cellulose-rich samples and confirmed a high glucose yield for the optimised methodology. Qualitative and quantitative analyses of the pre-treatment with ILs were made using the Fourier-Transform Infrared Spectroscopy (FT-IR). The NMR analysis was used to evaluate the purity of ILs after pre-treatments. Results of enzymatic hydrolysis analysis were controlled by the HPLC.
Busby, David Preston. "The cost of producing lignocellulosic biomass for ethanol." Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-07052007-124350.
Повний текст джерелаTyufekchiev, Maksim V. "Reaction Engineering Implications of Using Water for the Conversion of Lignocellulosic Biomass." Digital WPI, 2019. https://digitalcommons.wpi.edu/etd-dissertations/563.
Повний текст джерелаGupta, Shelaka. "Catalytic conversion of biomass-derived platform molecules : mechanistic insights, fundamental challenges and opportunities for rational catalyst design." Thesis, IIT Delhi, 2019. http://eprint.iitd.ac.in:80//handle/2074/8074.
Повний текст джерелаMu, Wei. "Aqueous phase processing of lignocellulosic biomass for biofuel production." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/53075.
Повний текст джерелаQueirós, Carla Sofia Gonçalves Pereira. "Lignocellulosic biomass for a new generation of thermal fluids." Doctoral thesis, ISA/UL, 2019. http://hdl.handle.net/10400.5/18319.
Повний текст джерелаThe increasing demand for fossil fuels, conjugated with the decreasing in oil reserves, led to a sharp rise of chemicals and materials derived from petroleum. Resulting in an increase desire from industry to seek for sustainable and alternative sources for key commodity chemicals or suitable equivalents Plant biomass represents one of the most important renewable energy sources for Europe, however much of the lignocellulosic biomass is often disposed of by burning, even in the rich and developed countries. Although, in the past years, there have been a strong effort in the research and valorisation of these residues. Therefore, lignocellulosic biomass can potentially be converted into different high value products including bio-fuels, value added fine chemicals, and cheap energy sources for microbial fermentation and enzyme production. The growing awareness of the need for energy efficiency gains requires new approaches for problems that, during the time of cheap energy and unlimited raw materials resources, were not the object of special care for industry and consequently, for research. In the case of heat and mass transfer, the increase in efficiency must be promoted by using new heat transfer fluids. Recently, ionic liquids (ILs) have proven to be suitable alternatives for many applications in industry and chemical manufacturing, even in the field of heat transfer and energy storage. Namely, the suspension of nanomaterials in ionic liquids proved to increase the thermal conductivity of the IoNanofluid in relation to the base ionic liquid. ILs have also being study in several biomass processes, particularly in the dissolution of cellulose
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Samayam, Indira Priya. "Characterization and Saccharification of Ionic Liquid Pretreated Lignocellulosic Biomass." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1313700629.
Повний текст джерелаWood, Brent E. "Improving Klebsiella oxytoca for ethanol production from lignocellulosic biomass." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0011422.
Повний текст джерелаLanigan, Brigid. "Microwave processing of lignocellulosic biomass for production of fuels." Thesis, University of York, 2010. http://etheses.whiterose.ac.uk/1237/.
Повний текст джерелаValenzuela, Mariefel Bayta. "Batch Aqueous-phase Reforming of Lignocellulosic Biomass for Hydrogen Production." Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/11624.
Повний текст джерелаDutta, Baishali. "Assessment of Pyrolysis techniques of lignocellulosic biomass for Biochar production." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95255.
Повний текст джерелаLa pyrolyse de biomasse à des températures excédant 300°C, suivi d'un retour au sol du produit de carbonisation de matériel biologique, s'avère une stratégie permettant de possiblement atténuer le changement climatique et réduire la consommation de combustibles fossiles. Dans la présente étude, nous tentâmes de créer un modèle d'éléments finis (MEF) permettant de coupler le réchauffement thermique et les phénomènes de transfert de chaleur et de masse opérant durant la pyrolyse. Cette démarche de modélisation et simulation numérique améliora notre habilité à visualiser le procédé et à optimiser la production de biochar. Des sections cylindriques de biomasse de bois de bouleau furent soumises à une pyrolyse dans un désorbeur thermique de laboratoire. L'influence de la température finale de pyrolyse, la vitesse d'élévation de température, et l'atmosphère de pyrolyse fut investiguée. Les résultants démontrèrent que tandis que le rendement en produits de pyrolyse diminua avec une augmentation de la température et du temps de la pyrolyse, le contenu en charbon du bois augmenta avec une augmentation ces paramètres, tout autant pour une pyrolyse lente qu'une pyrolyse rapide. A travers cette démarche, nous identifiâmes une technique permettant de maximiser la quantité de charbon dans les produits de pyrolyse ainsi que le rendement global du procédé. Le biochar ainsi généré fut testé par analyse immédiate et analyse calorimétrique à compensation de puissance afin de déterminer ses propriétés thermodynamiques, qui furent analysées et comparées selon les caractéristiques physiques des différents biochars, soit leur porosité et leur réflectance. fr
Maddi, Balakrishna. "Pyrolysis Strategies for Effective Utilization of Lignocellulosic and Algal Biomass." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1418340334.
Повний текст джерелаMaitan-alfenas, Gabriela Piccolo. "Enzymatic hydrolysis of lignocellulosic biomass for second generation ethanol production." Universidade Federal de Viçosa, 2014. http://www.locus.ufv.br/handle/123456789/6684.
Повний текст джерелаMade available in DSpace on 2015-11-16T11:43:38Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3547883 bytes, checksum: d0ecea27278208d99b9477d7546e1251 (MD5) Previous issue date: 2014-11-18
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A produção de etanol de segunda geração apresenta grande potencial para ser uma realidade sustentável, especialmente no Brasil que prossui grandes quantidades de bagaço de cana-de-açúcar. Os maiores obstáculos deste processo são os pré- tratamentos e a hidrólise da biomassa, principalmente esta última etapa visto que as enzimas ainda apresentam custos muito elevados. Assim, esforços têm se concentrado em tornar o processo mais econômico com a descoberta de enzimas mais efetivas. Novas fontes de enzimas são continuamente encontradas e várias estratégias de prospecção e produção enzimática têm sido estudadas. Uma estratégia bastante utilizada na busca por novas enzimas e/ou enzimas mais eficientes é a análise de genômica comparativa de diferentes micro-organismos que permite a seleção de vários candidatos de interesse num curto período de tempo. Além disso, as enzimas podem ser produzidas por fungos quando estes são crescidos em biomassas que apresentam baixo custo e alta disponibilidade. Este trabalho foi dividido em cinco capítulos sendo que o primeiro consiste de uma revisão atual sobre a produção de etanol de segunda geração focada na etapa de sacarificação enzimática. Várias estratégias de prospecção e produção enzimáticas foram discutidas e detalhadas. No segundo capítulo, a sacarificação de bagaço de cana-de-açúcar após pré-tratamentos ácido e alcalino foi comparada usando o extrato enzimático do fungo fitopatógeno Chrysoporthe cubensis e três coquetéis comerciais. Para o bagaço de cana utilizado neste estudo, o pré-tratamento alcalino promoveu os melhores rendimentos de sacarificação sendo o extrato do fungo C. Cubensis o responsável pela maior liberação de glicose e xilose quando comparado às misturas enzimáticas comerciais. Além disso, o extrato de C. cubensis produziu maiores valores de atividade específica comparados aos dos coquetéis comerciais. No terceiro capítulo, o potencial genômico de fungos candidatos foi avaliado e as enzimas mais interessantes para a hidrólise de bagaço de cana-de-açúcar foram expressas em Aspergillus vadensis. Nove enzimas de três fungos diferentes, Aspergillus terreus, Nectria haematoccoca e Phaeosphaeria nodorum, foram viiclonadas e expressas por sistema heterólogo e representam uma nova possiblidade para a melhor degradação do bagaço de cana. Dentre estas enzimas, quatro - xilosidases foram bioquimicamente caracterizadas e apresentaram atividade máxima em valores de pH 4,5-5,0 e em temperaturas 55-60°C. No quarto capítulo, duas xilanases de Aspergillus nidulans previamente clonadas em Pichia pastoris, aqui denominadas Xyn1818 e Xyn3613, foram expressas, purificadas e caracterizadas. Xyn1818 apresentou ótima atividade em pH 7.5 e à 60°C enquanto Xyn3613 alcançou máxima atividade em pH 6.0 e à 50°C. Xyn1818 apresentou-se bastante termoestável à 50°C mantendo 50% de sua atividade original após 49 horas de incubação nesta temperatura. Xyn1818 apresentou maior atividade contra arabinoxilana de trigo enquanto o melhor substrato para Xyn3613 foi xilana beechwood. Testes de sacarificação mostraram que os coquetéis comerciais liberaram mais açúcares (glicose e xilose) quando suplementados com as xilanases Xyn1818 e Xyn3613 de A. nidulans. Finalmente, no quinto capítulo, os fungos Aspergillus niger e Trichoderma reesei foram avaliados quanto à produção de enzimas após crescimento em do e bagaço de cana-de-açúcar. Os fungos produziram diferentes tipos de enzimas (hemi)celulolíticas, o que foi refletido pelo forte efeito sinergístico na liberação de açúcares durante a sacarificação dos substratos utilizando o conjunto de enzimas dos dois microorganismos. Foi constatado que a remoção de monossacarídeos do meio de produção de enzimas é muito importante quando combinações de enzimas de T. reesei and A. niger são utilizadas para aprimorar a hidrólise de biomassas.
Second generation ethanol production has great potential to be a sustainable reality, especially in Brazil due to the large amount of available sugarcane bagasse. Pretreatment methods and biomass hydrolysis continue to be the bottlenecks of the overall process, mainly this second step since the enzymes present high costs. Therefore, efforts have been taken to make the process more cost-effective with regards to the discovery of more effective enzymes. New sources of enzymes are continuously encountered and several strategies of enzyme prospection and production have been studied. One strategy used in the search for new and/or more efficient enzymes is comparative genomic analysis of different microorganisms which allows for the screening of several candidates of interest in a short period of time. Moreover, plant-degrading enzymes can be produced by fungi grown on abundantly available low-cost plant biomass. This work was divided in five chapters being the first chapter a current review about second generation ethanol production focused mainly on the saccharification step. Several strategies of enzyme prospection and production were discussed and detailed. In the second chapter, saccharification of acid- and alkali-pretreated sugarcane bagasse was compared using the enzymatic extract from the pathogen fungus Chrysoporthe cubensis and three commercial enzymatic mixtures. For the sugarcane bagasse studied in this work, the alkaline pretreatment promoted the best saccharification yields, where the C. cubensis extract was responsible for the higher release of glucose and xylose when compared to the commercial enzymatic mixtures Furthermore, the C. cubensis extract was able to produce high specific enzyme activities when compared to the commercial cocktails. In the third chapter, the genomic potential of the candidate fungi was evaluated and the most interesting enzymes for sugarcane bagasse hydrolysis were expressed in Aspergillus vadensis. Nine enzymes from three different fungi, Aspergillus terreus, Nectria haematoccoca and Phaeosphaeria nodorum, were successfully cloned and expressed by heterologous system and these enzymes represent a possibility for a better degradation of sugarcane bagasse. -xylosidases were biochemicallycharacterized and showed maxima activity in the pH range 4.5-5.0 and at temperatures of 55-60°C. In the fourth chapter, two xylanases from Aspergillus nidulans previously cloned in Pichia pastoris, here nominated as Xyn1818 and Xyn3613, were expressed, purified and characterized. The optima pH and temperature for Xyn1818 were 7.5 and 60°C while Xyn3613 achieved maximal activity at pH 6.0 and 50°C. Xyn1818 showed to be very thermostable, maintaining 50% of its original activity after 49 hours when incubated at 50°C. Xyn1818 presented higher activity against wheat arabinoxylan while Xyn3613 had the best activity against xylan from beechwood. Saccharification results showed that the commercial enzymatic cocktails were able to release more sugars (glucose and xylose) after supplementation with the xylanases Xyn1818 and Xyn3613 from A. nidulans. Finally, in the fifth chapter, Aspergillus niger and Trichoderma reesei were substrates: wheat straw and sugarcane bagasse. The fungi produced different sets of (hemi-)cellulolytic enzymes which was reflected in an overall strong synergistic effect in releasing sugars during saccharification using the enzyme blends from both fungi. It was observed that removing monosaccharides from the enzyme production media is very important when T. reesei and A. niger enzyme blends are combined to improve plant biomass saccharification.
Jones, Rudy. "Enhanced ethanol production: In-situ ethanol extraction using selective adsorption." Thesis, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/22658.
Повний текст джерелаDodo, Charlie Marembu. "Ethanol production from lignocellulosic sugarcane leaves and tops." Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1019839.
Повний текст джерелаRicciotti, Federica. "Plasma based pretreatments of lignocellulosic biomass for Biogas and Bioethanol production." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018.
Знайти повний текст джерелаZhu, Li. "Fundamental study of structural features affecting enzymatic hydrolysis of lignocellulosic biomass." Texas A&M University, 2005. http://hdl.handle.net/1969.1/4314.
Повний текст джерелаGourlay, Keith Ian. "The role of amorphogenesis in the enzymatic deconstruction of lignocellulosic biomass." Thesis, University of British Columbia, 2014. http://hdl.handle.net/2429/50850.
Повний текст джерелаForestry, Faculty of
Graduate
Rengel, Ana. "Study of Lignocellulosic Biomass Pyrolysis : State of the Art and Modelling." Thesis, KTH, Industriell ekologi, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-32757.
Повний текст джерелаwww.ima.kth.se
João, Karen Andreína Godinho. "Pre-treatment of different types of lignocellulosic biomass using ionic liquids." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/10386.
Повний текст джерелаThe pre-treatment of biomass by ionic liquid (IL) is a method opening new possibilities of biomass fractionation for further valorisation of low value feedstock. This work is dedicated to study on the pre-treatment and fractionation of different types of lignocellulosic biomass into its major constituent fractions (cellulose, hemicellulose and lignin), using ILs. The biomass tested was: wheat straw, sugarcane bagasse, rice straw and triticale. Initially, the optimised methods were development basing on two methodologies described in the literature. This method allows the separation into high purity carbohydrate-rich (cellulose and hemicellulose) and lignin-rich fractions and permits an efficient IL recovery. The possibility of IL reuse was confirmed, demonstrating the great potential of the established method. The pre-treatment of various biomasses confirms the versatility and efficiency of the optimised methodology since not only the complete macroscopic dissolution of each biomass was achieved but also the fractionation process was successfully performed. Pre-treatment of sugarcane bagasse and triticale allowed to obtained cellulose samples rich in carbohydrate up to 90 wt %. In order to verify the potential further applicability of the obtained carbohydrate-rich fractions, as well as to evaluate the pre-treatment efficiency, the cellulose-rich fraction resulting from 1-ethyl-3-methylimidazolium acetate ([emim][OAc]) pre-treatment was subjected to enzymatic hydrolysis. Results showed a very high digestibility of the cellulose-rich samples and confirmed a high glucose yield for the optimised pre-treatment methodology. The samples obtained after the pre-treatment with ILs were qualitatively and quantitatively analysed by Fourier Transform Infrared Spectroscopy (FTIR). After the pre-treatment, the purity of the recovered ILs was evaluated through Nuclear Magnetic Resonance spectroscopy (NMR). The enzymatic hydrolysis results were analysed by High-Performance Liquid Chromatography(HPLC).
Avery, Greg M. "A Life Cycle Assessment of Ionic Liquid Pretreatment for Lignocellulosic Biomass." University of Toledo / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1481273168926691.
Повний текст джерелаGiuliano, Aristide. "Process optimization of a lignocellulosic multi-product biorefinery." Doctoral thesis, Universita degli studi di Salerno, 2016. http://hdl.handle.net/10556/2364.
Повний текст джерелаA methodology to reduce the complexity of the process optimization was applied to multiproduct biorefinery fed by lignocellulosic biomass. A process superstructure was built to consider alternative process pathways to levulinic acid, succinic acid and ethanol. A Mixed Integer Non-Linear Problem was obtained and transformed in a Mixed Integer Linear Problem by means of a discretization procedure of the non-linear variables. Rigorous design methods accounting for complete kinetics schemes for hydrolysis and fermentation reactors for the production of levulinic acid, succinic acid and ethanol were included in a biorefinery superstructure optimization. A discretization method was applied to obtain a MILP approximation of the resulting MINLP master problem. The optimal flowsheet of a biorefinery with hardwood feedstock, obtained by maximizing the Net Present Value, yields comparable biomass allocation to levulinic acid and succinic acid (more than 40% each) and the its balance to ethanol. A sensitivity analysis highlighted that the optimal flowsheet and the relevant technical and economic performances are significantly dependent on the economic scenario (chemical products selling price, discount rate) and on the plant scale. Finally, process optimization achieved by maximizing two different economic objective functions, Net Present Value and Internal Rate of Return, provided different optimal flowsheets and biomass allocation to chemical products. The effect of the change of the biomass type and composition on the plant was also considered. Results highlight that the composition of the biomass feedstock in terms of cellulose, hemicellulose and lignin has a significant effect on the biomass allocation to the three product production processes and on the relevant optimal flowsheet. Case studies with a combined use of different seasonal biomass types during the year were also studied to provide a methodology to find the optimal biorefinery flowsheet in real scenarios. In the season based scenario studied, product yield distribution and overall productivity of the plant varies during the different periods provided a constant biomass feed rate. [edited by Author]
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Fonoll, Almansa Xavier. "Strategies to improve anaerobic digestion of wastes with especial attention to lignocellulosic substrates." Doctoral thesis, Universitat de Barcelona, 2015. http://hdl.handle.net/10803/379547.
Повний текст джерелаEl incremento de la demanda energética y la consecuente generación de residuos ponen en peligro la sostenibilidad del futuro. Es por eso que la digestión anaeróbica resulta ser una solución factible para mitigar el problema ya que se puede generar electricidad, calor y fertilizante a partir de los residuos orgánicos. El incremento de la producción de metano se consiguió a partir de la co-digestión de residuos con características complementarias. Aun así, no siempre se consigue extraer todo el potencial metanogénico de los residuos, especialmente, en el caso de los sustratos ligno-celulósicos. Los compuestos ligno¬celulósicos son estructuras complejos entre la lignina, la hemicelulosa y la celulosa con enlaces resistentes a la degradación microbiana que se encuentran en los residuos agro-industriales, los residuos municipales y los cultivos energéticos. En la tesis, se ha buscado aumentar la viabilidad económica de las plantas de digestión anaeróbica que tratan residuos con componentes ligno-celulósicos. Se usaron distintas nuevas estrategias para aumentar la degradabilidad de la materia ligno-celulósica como los pretratamientos térmicos de baja temperatura y de ultrasonidos y la integración del rumen, un residuo de la industria cárnica, para aportar bacterias hidrolíticas. Para valorar la opción de separar estos componentes para la formación de sub-productos, se estudió su efecto sobre el rendimiento del digestor en términos de estabilidad, producción de metano y calidad del digerido para así poder implementar la producción se sub-productos. Los estudios realizados en esta tesis doctoral se llevaron a cabo a escala de laboratorio y las conclusiones han supuesto un avance para el aprovechamiento energético de los residuos ligno-celulósicos en el futuro.
Narayana, Swamy Naveen. "Supercritical Carbon Dioxide Pretreatment of Various Lignocellulosic Biomasses." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1269524607.
Повний текст джерелаJackowiak, David. "Prétraitement de biomasses lignocellulosiques par microondes pour l'amélioration du procédé de biométhanisation." Compiègne, 2011. http://www.theses.fr/2011COMP1921.
Повний текст джерелаThe structure and composition of lignocellulosic biomass are known to be critical points to use this material in anaerobic digestion. Indeed, the presence of lignin forms a physical barrier and induces a non-productive adsorption and activity of enzymes. Therefore, this thesis aims at to study the effects of microwave heating of lignocellulosic material, especially on matter solubilisation through soluble COD, and on anaerobic digestion through BMP assays. Experimental studies were carried out on wheat straw and switchgrass, and revealed that their microwave pretreatments led to increase of matter solubilisation and an improvement of their anaerobic digestibility. The best conditions found are the highest heating rate for a final temperature 150°C without any holding time. A temperature beyond 150°C induces an increase of matter solubilisation but decreases the biodegradability of lignocellulosic material. This work studied also the energy balance. The energy calculated from the difference of methane production between treated and untreated sample does not compensate the energy consumed by the microwave pretreatment, at least with the microwave devices used. It therefore appears necessary to study the development of adapted industrial apparatus
Abels, Christian [Verfasser]. "Membrane separations in ionic liquid assisted processing of lignocellulosic biomass / Christian Abels." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://d-nb.info/1059535912/34.
Повний текст джерелаBerg, Heidi Odegård. "Comparison of conversion pathways for lignocellulosic biomass to biofuel in Mid-Norway." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk, 2013. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-22375.
Повний текст джерелаYan, Lishi. "Kinetic characterization of hot water and dilute acid pretreatment of lignocellulosic biomass." Thesis, Washington State University, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3628899.
Повний текст джерелаAcidic aqueous-phase pretreatment is a promising approach that has been directed at maximizing intermediates yields (e.g. sugars, sugar degradation products, and lignin) from biomass for fuel and chemical production. This dissertation explores the kinetic fundamentals of biomass hydrolysis in acidic aqueous-phase with different catalysts (e.g. sulfuric acid, metal chlorides), operating conditions (e.g. temperature, time pressure), and equipment configurations (e.g. batch, flowthough).
The kinetic analysis revealed that crystalline cellulose is insusceptible to hydrolysis compared with agarose at low temperature (e.g.140 °C), while it decomposed rapidly at elevated temperature (e.g. 220 °C). Higher temperature with reduced time was desirable for glucose production whereas lower temperature with prolonged time was preferred for xylose generation. In acidic conditions, furfural and levulinic acid were stable whereas 5-hydroxymethylfurfural was susceptible to decomposition with high rate constant. MgCl2 can promote the cleavage of C-O-C bond in polysaccharides (e.g. agarose) and enhance the subsequent dehydration reaction to 5-hydroxymethylfurfural. Unlike transition metal chlorides and H2SO4, MgCl2 has little ability to induce retro aldol and rehydration reactions to generate byproducts like lactic acid and levulinic acid. Mg2+ possessing hgiher activity than other alkali and alkaline earth metal chlorides (Na+ and Ca2+) resulted in 40.7% yield and 49.1% selectivity of 5-hydroxymethylfurfural.
Dissolution of biomass was significantly enhance using acidic hot water flowthrough pretreatment at 200—280°C. Significant cellulose removal accompanied with the transformation of cellulose I to cellulose II and amorphous cellulose were observed when temperature was above 240 °C for water-only and 220 °C for dilute acid. Approximately100% of the xylan and ∼90% of the cellulose were solubilized and recovered. Up to 15% of the lignin was solubilized, while the remaining lignin was insoluble. Over 90% sugar yields were obtained from pretreated whole slurries using less than 10 FPU/g cellulase plus hemicellulase enzyme.
A kinetic model was developed to depict the biomass degradation in flowthrough system. This model predicted the sugar generation more precisely than the conventional homogeneous first-order reaction models. Mass transfer limitations were minimized using 4mm biomass particle sizes with 4g biomass loading at 25mL/min flow rate, produced hydrolyzate slurries with 13g/L potential sugar concentrations.
Godoy, Jayfred Gaham Villegas. "Sorghum improvement as biofuel feedstock: juice yield, sugar content and lignocellulosic biomass." Thesis, Kansas State University, 2011. http://hdl.handle.net/2097/9254.
Повний текст джерелаDepartment of Agronomy
Tesfaye Tesso
Sorghum [Sorghum bicolor (L.) Moench] is listed as one of the potential feedstock sources for biofuel production. While sorghum grain can be fermented into ethanol in a similar way as maize, the greatest potential of the crop is based on its massive biomass and sugar rich juices. Thus development of the crop as alternative energy source requires improvement of these traits. The objectives of this study were (1) to determine the mode of inheritance of traits related to ethanol production and identify suitable genetic sources for use in breeding programs, and (2) to evaluate the potential of low lignin mutations for biomass feedstock production and assess biotic stress risks associated with deployment of the mutations. The study consisted of three related experiments: (i) estimating the combining ability of selected sweet and high biomass sorghum genotypes for biofuel traits and resistance to stalk lodging, (ii) determine the impact of brown mid-rib mutations on biofuel production and their reaction to infection by Macrophomina phaseolina and Fusarium thapsinum, and (iii) assess the reaction of low lignin mutants to green bug feeding. In the first experiment six sorghum genotypes of variable characteristics (PI193073, PI257602, PI185672, PI195754, SC382 and SC373) were crossed to three standard seed parent lines ATx3042, ATx623 and ATx399. The resulting hybrids and the parents were evaluated at four locations, three replications during 2009 and 2010 seasons. Data were collected on phenology, plant height, juice yield, °brix score and biomass production. In the second experiment, two brown mid-rib mutations (bmr6 and bmr12) and their normal versions were studied in four forage sorghum backgrounds (Atlas, Early Hegari, Kansas Collier and Rox Orange). The experiment was planted in four replications and at 14 d after flowering five plants in a plot were artificially infected with F. thapsinum and another five with M. phaseolina. The plants were harvested and rated for disease severity (lesion length and nodes crossed). Another five normal plants in each plot were harvested and used to determine biofuel traits (juice yield, ºbrix score and biomass). In the third experiment, a subset of entries evaluated in experiment II and three tolerant and susceptible checks were tested for greenbug feeding damage. Biotype K greenbug colony was inoculated to each genotype using double sticky foam cages. Feeding damage was assessed as percent chlorophyll loss using SPAD meter. There was significant general combining ability (GCA) effect among the male entries for juice yield, stem obrix and biomass production indicating that these traits are controlled by additive genes. Lines PI257602 and PI185672 in particular, had the highest GCA for all the traits and should serve as excellent breeding materials. There was no significant difference among the bmr mutants and between the bmr and normal genotypes for both stalk rot and greenbug damage. In conclusion, juice yield, °brix and biomass are largely controlled by additive genes and hence are amenable to genetic manipulation. The bmr mutations despite their impact on lignin content do not increase risk of attack by stalk rot pathogens and greenbugs and thus can be deployed for biofuel production without incurring losses to these factors.
Tyufekchiev, Maksim V. "Reaction Engineering Implications of Using Water for the Conversion of Lignocellulosic Biomass." Digital WPI, 2020. https://digitalcommons.wpi.edu/etd-dissertations/619.
Повний текст джерела