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BiomassComposition and Conversion TechnologiesLe Cao Nhien2015-02-271

Biofuel classificationBioethanol, butanol from starch, sugarBiodiesel from plant oilsBiomethane, Bioethanol, butanol, biodiesel from lignocelluloseBioethanol, biodiesel, hydrogen from algae#2 major subdivisions:Crop: corn, sugarcane, soybean, wheatcontain carbohydrates, glucose, starchWood: composed cellulose, hemicellulose, ligninStarch+cellulose: polymetric forms of glucose, C6 sugarHemicellulose: polymer of xyloseLignin: phenolic polymersOils: triglyceridesBiomass classification and composintionRef. integrating bioprocesses into..2012

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Polymer of glucose, 10%30% -amylose and 70%90% amylopectinThe -1,4-glycosidic linkages are bent and prevent the formation of sheets and subsequent layering of polymer chains.Starch is soluble in water and relatively easy to break down into utilizable sugar units.Starch

#GlycogenThis is similar in structure to amylopectin. It is poly (1-4) glucose with 9% (1-6) branches.

It is made by animals as their storage polysaccharide, and is found mainly in muscle and liver. Because it is so highly branched, it can be mobilised (broken down to glucose for energy) very quickly. It is broken down to glucose by the enzyme glycogen phosphorylase.

#Contains 30%50% cellulose, 20%30% hemicellulose, and 20%30% ligninConsidered to be an abundant resource for the future bioindustryCellulosic biomass comprises 35%50% of most plant materialPolymer of glucose with degree of polymerization of 1,00010,000It is poly (1-4) glucose, but with a different isomer of glucose. Lignocellulosic

#Whereas the 14 glucose polymer in starch coils up to form granules, the 14 glucose polymer in cellulose forms straight chains. Hundreds of these chains are linked together by hydrogen bonds to form cellulose microfibrils. These microfibrils are very strong and rigid, and give strength to plant cells, and therefore to young plants and also to materials such as paper, cotton and sellotape.

Starch and Cellulose

#coils (cun) up to form granules (ht nh), 7Comparison between Starch, Glycogen and Cellulose

#Containing primarily five-carbon sugars such as xylose and arabinose with some glucose and mannose dispersed throughoutIt forms a short-chain polymer that interacts with cellulose and lignin to form a matrix in the plant wall.More easily hydrolyzed than celluloseMuch of the hemicellulose in lignocellulosic materials is solubilized and hydrolyzed to pentose and hexose sugars during the pretreatment stage.Hemicellulose

#Helps to bind the cellulose/hemicelluloses matrix while adding flexibility to the mixtureThe molecular structure of lignin polymers is very random and disorganized and consists primarily of carbon ring structures (benzene rings with methoxyl, hydroxyl, and propyl groups) interconnected by polysaccharides (sugar polymers).The ring structures of lignin have great potential as valuable chemical intermediates, mainly aromatic compoundsLignin

Separation and recovery of the lignin is difficult. Pyrolysis can be used to convert the lignin polymers to valuable products, but separation techniques to recover the individual chemicals are lacking#

#Oils can be obtained from oilseeds like soybean, canola, etc. Vegetable oils are composed primarily of triglycerides, also referred to as triacylglycerols.Triglycerides contain a glycerol molecule as the backbone with three fatty acids attached to glycerols hydroxyl groupsOils

#Biomass conversion technology

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#The cellulose and hemicellulose in the biomass are broken down to their monomeric form.Produce a solid pretreated biomass residue that is more amenable to enzymatic hydrolysis by cellulases and elated enzymes than native biomassRemoves the lignin in biomassHot wash pretreatment: Responsible for solubilization of the hemicellulose fraction. Depends on temperature and flow rate, requiring about 816min. About 46% of lignin is removed at high rates and temperatures.Acid hydrolysis:A chemical reaction or process where a chemical compound reacts with waterBreak complex polymer structures into its component monomersEnzymatic hydrolysisAcid hydrolysis explained earlier has a major disadvantage where the sugars are converted to degradation products like tars. This degradation can be prevented by using enzymes favoring 100% selective conversion of cellulose to glucoseBiomass Pretreatment (1/5)

#Fermentation process where pretreated biomass containing five-carbon and six-carbon sugars is catalyzed with biocatalysts to produce desired productsFermentation refers to enzyme-catalyzed, energy-yielding chemical reactions that occur during the breakdown of complex organic substrates in the presence of microorganisms (Klass, 1998)The microorganisms can be yeast or bacteriaEthanol is produced by the bacteria Zymomonous mobilis or the yeast Saccaromyces cervisiae.Succinic acid is produced in high concentrations by Actinobacillus succinogens obtained from rumen ecosystemFermentation (2/5)

#The fermentation process begins by adding yeast to a mixture of grain, flavoring agents, and water,which are prepared to maximize their available sugar. Inside the fermentation tank the yeast converts sugarinto alcohol, carbon dioxide, and other products through a natural process known as fermentation.16How to ferment beer?

#The treatment of biomass with a mixed culture of bacteria to produce methane (biogas) as a primary productAnaerobic Digestion (3/5)

#Anaerobic Digestion (3/5)

#The reaction of an alcohol with natural oil containing triglycerides to produce monoalkyl esters and glycerolThe alcohols that can be used for transesterification depend on the type of esters desired. Methanol (CH3OH) gives methyl esters and ethanol (C2H5OH) produces ethyl estersA wide variety of vegetable oils and natural oils can be used for transesterification.Transesterification (4/5)

#Transesterification (4/5)Haas et al. (2006) describe an industrial-scale transesterification process for the production of methyl esters from the transesterification of soybean oil.

#Transesterification (4/5)Retrofit of distillation columns in biodiesel production plants, 2010, Nghi Nguyen

#Thermal conversion processes such as gasification and pyrolysis can be used to convert biomass to synthesis gas, a mixture of carbon monoxide and hydrogen (1:1)Pyrolysis is the direct thermal decomposition of the organic components in biomass in the absence of oxygen to yield an array of useful products like liquid and solid derivatives and fuel gases (Klass, 1998).In the 1800s, coal gasification was used to provide syngas used for lighting and heating.With the development of the petroleum industry in the 1940s, the economics of many of these syngas routes became unfavorable and these were replaced by petroleum-based processes.Commercial biomass gasification facilities started worldwide in the 1970s

Gasification (5/5)#Gasification (5/5)

#The direct thermal decomposition of the organic components in biomass in the absence of oxygen to yield an array of useful products like liquid and solid derivatives and fuel gasesConocoPhillips has funded a $22.5 million and 8 year research program at Iowa State University to develop new technologies for processing lignocellulosic biomass to biofuels (C&E News, 2007b). The company wants to investigate routes using fast pyrolysis to decompose biomass to liquid fuels.Pyrolysis (5/5)

#Biomass particles are fed near the bottom of the pyrolysis reactor together with an excess flow of hot heat carrier material such as sand, where it is being pyrolysed. The produced vapours pass through several cyclones before entering the condenser, in which the vapours are quenched by re-circulated oil. The pyrolysis reactor is integrated in a circulating sand system composed of a riser, a fluidized bed char combustor, the pyrolysis reactor, and a down-comer. In this concept, char is burned with air to provide the heat required for the pyrolysis process. Oil is the main product; non-condensable pyrolysis gases are combusted and can be used e.g. to generate additional steam. Excess heat can be used for drying the feedstock.25Thank You for your Attention!Le Cao Nhien, Ph.D. StudentProcess Systems Design and Control LaboratorySchool of Chemical Engineering, Yeungam UniversityDae-dong 214-1, Gyeongsan 712-749, South KoreaEmail: nhienle10@gmail.comWebsite: http://psdc.yu.ac.kr

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