Dissertations / Theses on the topic 'Feedstock pretreatment'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 17 dissertations / theses for your research on the topic 'Feedstock pretreatment.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Burkhardt, Sabrina Jane. "Forest residues as a potential feedstock for a biorefinery : material balance and pretreatment strategies." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/45019.
Full textHu, Zhoujian. "Utilization of switchgrass as a biofuel feedstock." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44088.
Full textSrinivasan, Narayanan. "Pretreatment of Guayule Biomass Using Supercritical CO2-based Method for Use as Fermentation Feedstock." University of Akron / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=akron1289782016.
Full textChang, Chen-Wei. "Bioconversion of sugarcane bagasse and soybean hulls for the production of a generic microbial feedstock." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/bioconversion-of-sugarcane-bagasse-and-soybean-hulls-for-the-production-of-a-generic-microbial-feedstock(0144bdd8-5444-468d-9f0f-50613a79be67).html.
Full textDu, Bowen Chambliss C. Kevin. "Effect of varying feedstock-pretreatment chemistry combinations on the production of potentially inhibitory degradation products in biomass hydrolysates." Waco, Tex. : Baylor University, 2009. http://hdl.handle.net/2104/5319.
Full textBaral, Nawa Raj. "Techno-economic Analysis of Butanol Production through Acetone-Butanol-Ethanol Fermentation." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1480501106426567.
Full textHosseini, Majid. "Sustainable Pretreatment/Upgrading of High Free Fatty Acid Feedstocks for Biodiesel Production." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1386749821.
Full textGuragain, Yadhu Nath. "Sustainable bioprocessing of various biomass feedstocks: 2,3-butanediol production using novel pretreatment and fermentation." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/20426.
Full textGrain Science and Industry
Praveen V. Vadlani
Lignocellulosic biomass feedstocks are a sustainable resource required for rapid growth of bio-based industries. An integrated approach, including plant breeding, harvesting, handling, and conversion to fuels, chemicals and power, is required for the commercial viability of the lignocellulosic-based biorefineries. Optimization of conversion processes, including biomass pretreatment and hydrolysis, is a challenging task because of the distinct variations in composition and structure of biopolymers among biomass types. Efficient fermentation of biomass hydrolyzates comprising of different types of sugars is challenging. The purpose of this doctoral research was to evaluate and optimize the various processing steps in the entire the biomass value chain for efficient production of advanced biofuels and chemicals from diverse biomass feedstocks. Our results showed that densification of bulky biomass by pelleting to better streamline the handling and logistic issues improved pretreatment and hydrolysis efficiencies. Alkali pretreatment was significantly more effective than acid pretreatment at same processing conditions for grass and hardwood. The ethanol-isopropanol mixture, and glycerol with 0.4% (w/v) sodium hydroxide were the promising organic solvent systems for the pretreatment of corn stover (grass), and poplar (hardwood), respectively. None of the pretreatment methods used in this study worked well for Douglas fir (softwood), which indicates a need to further optimize appropriate processing conditions, better solvent and catalyst for effective pretreatment of this biomass. The brown midrib (bmr) mutations improved the biomass quality as a feedstock for biochemicals production in some sorghum cultivars and bmr types, while adverse effects were observed in others. These results indicated that each potential sorghum cultivar should be separately evaluated for each type of bmr mutation to develop the best sorghum line as an energy crop. Development of an appropriate biomass processing technology to generate separate cellulose and hemicellulose hydrolyzates is required for efficient 2,3-butanediol (BD) fermentation using a non-pathogenic bacterial strain, Bacillus licheniformis DSM 8785. This culture is significantly more efficient for BD fermentation in single sugar media than Klebsiella oxytoca ATCC 8724. Though K. oxytoca is a better culture reported so far for BD fermentation from diverse sugars media, but it is a biosafety level 2 organism, which limits its commercial potential.
Agbor, Valery. "Processing of lignocellulosics feedstocks for biofuels and co-products via consolidated bioprocessing with the thermophilic bacterium, Clostridium thermocellum strain DSMZ 1237." Biotechnology Advances / ELSEVIER, 2011. http://hdl.handle.net/1993/30647.
Full textOctober 2015
Liu, Enshi. "FRACTIONATION AND CHARACTERIZATION OF LIGNIN STREAMS FROM GENETICALLY ENGINEERED SWITCHGRASS." UKnowledge, 2017. http://uknowledge.uky.edu/bae_etds/49.
Full textWang, Jui-Tzu, and 王瑞慈. "Impact of Feedstock Pretreatment on Characteristic of Cellulose Films." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/2gfcn9.
Full text國立臺灣大學
森林環境暨資源學研究所
106
The objective of this experiment is to obtain the eco-friendly and well-aligned cellulose film. The experiment divide into two parts. First, we use three materials (BEK, Avicel and bacterial cellulose) treated with pretreatment and use N-methylmorpholine-N-oxide (NMMO) to produce regenerated cellulose films. Second, bacterial cellulose is cultivated on different condition. We use statistic method, POM, SEM, profilometer, and AFM to determine the morphology of cellulose films and use GPC and DP to determine the properties of cellulose. The pretreatment used in this research is phosphorylation and polyelectrolytes. Phosphorylation and polyelectrolytes help cellulose dissolve in NMMO which decrease the roughness of thin films.Bacterial cellulose is cultivated in different condition, such as substrate, tilt height and condition mode. The result shows that tilt height,substrate and condition mode can''t influence the roughness of bacterial cellulose. However, the alignment of bacterial cellulose can be influenced by fluid direction. Pretreatment can obtain well-aligned cellulose film which can be applied in many different field.
Xaba, Nqobile. "Use of amaranth as feedstock for bio-ethanol production / Nqobile Xaba." Thesis, 2014. http://hdl.handle.net/10394/12230.
Full textMSc (Engineering Sciences in Chemical Engineering), North-West University, Potchefstroom Campus, 2014
Moisan, Maxime. "Ultrasonic Pretreatment for Anaerobic Digestion: a Study on Feedstock, Methane Yield, and Energy Balance." Thesis, 2012. http://hdl.handle.net/10214/5091.
Full textMITACS
Schabort, Cornelis Johannes. "Evaluation of suitability of water hyacinth as feedstock for bio-energy production / Cornelis JohannesJ. Schabort." Thesis, 2014. http://hdl.handle.net/10394/11969.
Full textMIng (Chemical Engineering), North-West University, Potchefstroom Campus, 2014
"Effect of pretreatment on the breakdown of lignocellulosic matrix in barley straw as feedstock for biofuel production." Thesis, 2014. http://hdl.handle.net/10388/ETD-2014-10-1609.
Full textRobinson, Jamie. "Pretreatment and fermentation of Douglas-fir whitewood and bark feedstocks for ethanol production." Thesis, 2003. http://hdl.handle.net/2429/15073.
Full textPereira, Ana Rita Pontes. "Optimizing the scale up biochemical platform biorefinery for lactic acid production from lignocellulosic biomass." Doctoral thesis, 2021. http://hdl.handle.net/10316/96395.
Full textLignocellulosic biomass, such as forest and agriculture residues or dedicated energy crops, is a promising renewable feedstock for the production of advanced biofuels and chemical building blocks. Lactic acid (LA) has been identified as one with high potential, playing an essential role in industrial applications ranging from the food industry to life-sciences. Moreover, LA is widely used for producing green, biodegradable and biocompatible polylactic acid polymers (PLA). In order to develop an efficient process for the production of LA from lignocellulosic biomass, complementary to the selection of the biomass, process optimization must be carried out. For this, three main operations have to be considered - (1) biomass pretreatment, (2) enzymatic saccharification to obtain fermentable sugar by cellulases and (3) the fermentation of sugars by suitable microorganisms to lactic acid. The selection of the raw material as well as the development of the main process operations are the focus of this work. The selection of the raw material was focused on evaluating two mixtures of lignocellulosic biomass (M1-4 and M2-3), forest ecosystems and biological resources from marginal land, in order to co-produce oligosaccharides, solid fuel and glucose under a biorefinery concept. The selection of mixtures was based on different criteria, namely, territorial distribution, fire risk during summer months and total sugar content. The two mixtures were submitted to autohydrolysis pretreatment under non-isothermal conditions (in the range of 190 ºC - 240 ºC corresponding to severity of 3.71 to 4.82). Both mixtures were compared in terms of fractionation (cellulose and lignin recoveries and hemicellulose solubilization) and for enzymatic susceptibility of cellulose. The highest xylan recoveries (62 and 69 %), as xylose and xylooligosaccharides, were achieved for both mixtures in the liquid phase at 206 ºC. Moreover, enzymatic susceptibility of these pretreated mixtures was also improved from 45 to 90 % of glucose yield by increasing pretreatment severity and at 206 ºC glucose yield from enzymatic hydrolysis resulted in 60.1 % and 73.7 % for M1-4 and M2-3, respectively, these results led to the selection of the mixture M2-3 for further processing. The solid fraction of M2-3 resulted from autohydrolysis (AM2-3) at 206 ºC was subsequently delignified by uncatalyzed ethanol-organosolv process to recover hemicellulose, cellulose and lignin in separate streams. Three factors were evaluated in the experimental design of organosolv process: ethanol concentration (30–80%), temperature (160–200 ºC) and time (20–60 min). Organosolv process showed that the best compromise between lignin removal and cellulose preservation was obtained at highest temperature and ethanol concentration (p-value of 0.05). Maximal delignification (49.40%) was obtained at the highest severity condition (200ºC, 60 min, 80 % EtOH). Moreover, 35.32 g/L glucose, corresponding to a glucose yield of 49.65 %, was produced from enzymatic hydrolysis of delignified biomass. FTIR analysis of the isolated lignins (OL1–OL10) showed that the main lignin structure was not changed, while thermal analysis revealed Tg values from 73 to 85 ºC. All OL presented radical scavenging activity as high as the commercial antioxidant BHT. Considering the glucose yield of solid fraction from AM2-3 and from organosolv, the last one did not increased enzymatic susceptibility and for this reason the following processes did not include this step. Whereas enzymatic susceptibility improved by increasing pretreatment severity, M2-3 was presented to autohydrolysis pretreatment at 226 ºC .The solid fraction (AM2-3) obtained was submitted to separated hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) for LA production. LA yield on glucose obtained for both assays was 1 g/g, although the volumetric productivity of SSF (2.5 g/Lh) was higher than SHF (0.8 g/Lh). Therefore, the SSF process was optimized through a factorial design to evaluate the effect of independent variables, solids load and enzyme-substrate ratio (ESR), on LA production. The maximum concentration of LA was obtained using the highest solids load (16 %) and with the highest ESR (54 FPU/g). Finally, scale up of LA was performed in a bioreactor under the optimized conditions in Erlenmeyer flasks, being obtained 61.74 g/L of LA at 44 h which corresponds to LA yield of 0.97 g/g. In order to present a quantitative evaluation of the environmental loads associated with LA production from M2-3, it was compared with the lactic acid production from non-renewable resources and modeled using the Life Cycle Assessment method through SimaPro®. The life cycle approach took into account the raw material, transport, pretreatment, saccharification and fermentation and LA recovery considering 1 tonne of LA as the functional unit. The major environmental savings obtained by replacing one tonne of fossil-based LA by biobased LA are : 4056.60 kg CO2 eq. of global warming potential; 193.03 kBq U235 eq. of ionizing radiation potential; 3.78 kg C2H4 eq of photochemical oxidation potential; 0.73 kg PO4 3- eq freshwater eutrophication potential; 9569.40 kg 1,4-DB eq. of terrestrial ecotoxicity potential; 99.32 kg 1,4-DB eq. of fresh water aquatic ecotoxicity potential; 137.69 kg 1,4-DB eq. of marine aquatic ecotoxicity potential; 94.89 human toxicity potential and 126.63 m2 of land use. Auxiliary chemicals, electricity and enzyme used in the biobased LA production are most relevant to the total environmental impacts. Biobased LA production significantly reduces the impact on the environment, giving 60 % environmental savings compared to fossil-derived LA. The results obtained in this work demonstrate the potential of lignocellulosic biomass as an unexploited raw material for an economical and environmental viable solution to produce lactic acid by fermentation.
A biomassa lenhocelulósica, como resíduos florestais e agrícolas ou culturas energéticas dedicadas, é uma matéria-prima renovável promissora para a produção de biocombustíveis avançados e químicos de plataforma. O ácido láctico (LA) foi identificado como um de elevado potencial, desempenhando um papel essencial em aplicações industriais, que vão desde a indústria alimentar até às ciências da vida. Além disso, o ácido láctico é amplamente utilizado na produção de polímeros de ácido poliláctico (PLA) verdes, biodegradáveis e biocompatíveis. A fim de desenvolver um processo eficiente de produção de LA a partir de biomassa lenhocelulósica, complementar à seleção da biomassa, a otimização do processo deve ser realizada. Assim, três operações principais devem ser consideradas: (1) pré-tratamento da biomassa, (2) sacarificação enzimática para obter açúcares fermentáveis através de celulases e (3) fermentação de açúcares por microrganismos adequados ao ácido láctico. A seleção da matéria-prima, bem como o desenvolvimento das principais operações do processo são o foco deste trabalho. A seleção da matéria-prima centrou-se na avaliação de duas misturas de biomassa lenhocelulósica (M1-4 e M2-3), ecossistemas florestais e vegetação natural, com o objetivo de coproduzir oligossacarídeos, combustível sólido e glucose sob um conceito de biorrefinaria. A seleção das misturas foi baseada em diferentes critérios, nomeadamente a distribuição territorial, risco de incêndio durante os meses de Verão e teor total de açúcar. As duas misturas foram submetidas a um pré-tratamento de autohidrólise em condições não isotérmicas (na gama de 190 ºC - 240 ºC correspondente a uma severidade de 3.71 a 4.82). Ambas as misturas foram comparadas em termos de fracionamento (recuperações de celulose e lenhina e solubilização de hemicelulose) e de suscetibilidade enzimática da celulose. As maiores recuperações de xilanos (62 e 69 %), como xilose e xilooligossacarídeos, foram obtidas para ambas as misturas na fase líquida a 206 ºC. Além disso, a suscetibilidade enzimática destas misturas pré-tratadas foi também melhorada de 45 a 90 % em rendimento da glucose, com o aumento da severidade do pré-tratamento e, a 206 ºC, o rendimento de glucose da hidrólise enzimática resultou em 60.1 % e 73.7 % para M1-4 e M2-3, respectivamente, esses resultados levaram à seleção da mistura M2-3 para os processos posteriores. A fração sólida resultante da auto-hidrólise (AM2-3) a 206 ºC foi subsequentemente delignificada pelo processo de etanol-organosolv não catalisado para recuperar hemicelulose, celulose e lenhina em fluxos separados. Foram avaliados três fatores no desenho experimental do processo organosolv: concentração de etanol (30-80 %), temperatura (160-200 ºC) e tempo (20-60 min). O processo organosolv mostrou que o melhor compromisso entre a remoção da lignina e a preservação da celulose foi obtido nas condições extremas de temperatura e concentração de etanol (p-value de 0.05). A delignificação máxima (49.40%) foi obtida na condição de maior severidade (200 ºC, 60 min, 80 % EtOH). Além disso, 35.32 g/L de glucose, correspondendo a um rendimento de glucose de 49.65 %, foi produzida a partir da hidrólise enzimática da biomassa delignificada. A análise FTIR das lenhinas isoladas (OL1-OL10) mostrou que a estrutura principal da lenhina não foi alterada, enquanto que a análise térmica revelou valores de Tg de 73 a 85 ºC. Todas as lenhinas (OL1-OL10) apresentavam atividade antioxidante tão elevada quanto o antioxidante comercial BHT. Considerando o rendimento de glucose da fração sólida do AM2-3 e do organosolv, este último não aumentou a suscetibilidade enzimática e por esse motivo os processos a seguir não incluíram esta etapa. Considerando que a suscetibilidade enzimática melhorou com o aumento da severidade do pré-tratamento, M2-3 foi submetido ao pré-tratamento de auto-hidrólise a 226 ºC. A fração sólida (AM2-3) obtida foi submetida a hidrólise e fermentação em separado (SHF) e sacarificação e fermentação em simultâneo (SSF) para produção de LA. O rendimento de LA em glucose obtido para ambos os ensaios foi de 1 g/g, embora a produtividade volumétrica de SSF (2.5 g/Lh) tenha sido superior a SHF (0.8 g/Lh). Portanto, o processo SSF foi otimizado através de um desenho fatorial para avaliar o efeito das variáveis independentes, carga de sólidos e relação enzima-substrato (ESR), na produção de LA. A concentração máxima de LA foi obtida com a maior carga de sólidos (16 %) e com a maior ESR (54 FPU/g). Por fim, o aumento de escala do LA foi realizado em biorreator nas condições otimizadas nos frascos Erlenmeyer, sendo obtido 61.74 g/L de LA às 44 h que corresponde a rendimento de LA de 0.97 g/g. Para apresentar uma avaliação quantitativa das cargas ambientais associadas à produção de LA a partir de M2-3, esta foi comparada com a produção de ácido láctico a partir de recursos não renováveis e foi modelada utilizando o método de Avaliação do Ciclo de Vida através do SimaPro®. A abordagem do ciclo de vida teve em conta a matéria-prima, transporte, pré-tratamento, sacarificação e fermentação e recuperação de LA, considerando 1 tonelada de LA como a unidade funcional. As maiores poupanças ambientais obtidas através da substituição de uma tonelada de LA de base fóssil por LA de base biológica são : 4056.60 kg CO2 eq. de potencial de aquecimento global; 193.03 kBq U235 eq. de potencial de radiação ionizante; 3.78 kg C2H4 eq de potencial de oxidação fotoquímica; 0.73 kg PO43- eq de potencial de eutrofização de água doce; 9569.40 kg 1,4-DB eq. de potencial de ecotoxicidade terrestre; 99.32 kg 1,4-DB eq. de potencial de ecotoxicidade aquática de água doce; 137.69 kg 1,4-DB eq. de potencial de ecotoxicidade aquática marinha; 94.89 potencial de toxicidade humana e 126.63 m2 de uso da terra. Os produtos químicos auxiliares, eletricidade e enzimas utilizados na produção de LA de base biológica são os mais relevantes para os impactos ambientais totais. A produção de LA de base biológica reduz significativamente o impacto sobre o ambiente, proporcionando 60 % de poupança ambiental em comparação com o LA de origem fóssil. Os resultados obtidos neste trabalho demonstram o potencial da biomassa lignocelulósica como matéria-prima inexplorada para uma solução económica e ambientalmente viável para a produção de ácido lático por fermentação.
BLC3 Evolution Lda