Quantitative/Qualitative Analysis And Application Of Main Products Formed From Deoxy-decomposition Of Biomass

The energy consumption in the world has been increased in these years, as the development of this world. However, the fossil resource is limited, whose amount is decreasing as the increasing requirement of human. Several researchers have been working on the sustainable and renewable bio-energy with high efficiency. In this study, most of jobs were operated on the bio-energy with high efficiency and technology on the bio-energy in the industry.The wet-decomposition of lignocellulose with high efficience was carried out in the first section of the present study. During the decomposition of biomass, the main problems were focused on the low conversion, the higher residue yield and the higher requirement of operation temperature and pressure, respectively. Therefore, the synergistic solvent was introduced into the wet-decomposition system. It was shown by the results that the residue yield was reduced in the1,4-dioxane-water mixture. In that mixture, water played as a nucleophile and reacts with some active centers in the protolignin. Meanwhile, The1,4-dioxane solvent solubilizes the cellulose and semi-cellulose, and impregnates the plant tissue, carrying the reagents to the protolignin and the resulting lignin fragments from the inner part of the cell to the solution. After then, several reactions were improved.During the wet-decomposition of biomass, intermediate products and free radicals were reacted as polymerization and repolymerization. The solid products, named as residue, were the main products, when the runs were operated at low temperature. The decomposition of lignin was enhanced with increasing the reaction temperature. The phenoxy radicals were produced from the decomposition of lignin, while other kinds of radicals were produced from the the decomposition of cellulose and hemicellulose. They always polymerized with the intermediate products from the redecomposition of decomposition products. After then, the final products were produced. The solubility and mass transfer ability of mixture were significantly improved, and consequently enhanced the wet-decomposition of rice straw, which improved the formation of light fractions.The wet-decomposition system of lignocellulose was received hydrogen from hydrogen-donor. Several properties of final products could be improved by the hydrogen-transfer process. The effects of hydrogen-donor on the wet-decomposition of lignocellulose were investigated in this study. The wet-decompositions of lignocellulose in the ethanol-water mixture and2-proponal-water mixture were carried out, in order to identify the properties of hydrogen-donor during the wet-decomposition process. Several parameters were involved in this study, such as temperature, holding time and mixture ratio.The hydrogen in biomass and α-hydrogen from hydrogen-donor were combined with the oxygen in the system, and then produced water during the hydrogenation. Meanwhile, the carbon in the system was combined with oxygen, and then produced carbon monoxide and carbon dioxide. Those two processes are the main oxygen removal routes during the wet-decomposition. The higher heating values of liquid products were enhanced by the removal of oxygen. The mixture of alcohol and water could play as synergistic solvent as the nucleophilicity of water and hydrogenation of alcohol. The wet-decomposition of biomass could be improved by the synergistic solvent.The formation of light fraction was improved with temperature increasing as removal of oxygen. The removal of oxygen was due to the formation of carbon dioxide/carbon monoxide and water during the wet-decomposition of rice straw in mixture of ethanol-water or2-proponal-water mixture. The intermediate products were further decomposed, which produced smaller compounds and volatiles. Therefore, the yield of light fraction was increased. The hydrogen from ethanol and2-proponal could stabilize the free radicals and fragments from decomposition of lignocellulose via the polymerization. Therefore, the formations of smaller compounds and volatiles were enhanced.More and more kinds of waste were produced as human activities. The ideal situation is that most of the waste can be converted into energy or other useful products. The feedstock should be picked up around local area or somewhere with low transportation cost. As the development of maniple waste water plants, the treatment of sludge is one of the importants fields for scientists. The conversion of sludge into energy or other useful products with high efficiency is one of the hot fields. As there are few lignocelluloses in sludge, the decomposition process is much easier compared with typical biomass. Compared with typical biomass, similar situation can be indicated that the deoxygenation and decarboxylation was still one of the main reactions in the wet-decomposition of sludge. Solvent filling ratio affected the wet-decomposition of sludge significantly. The repolymerization reaction was improved with higher solvent filling ratio. Polymerized products were extracted into the liquid and solid fraction, resulting in the increment of oil and residue yields. The oxygen was introduced into those products with repolymerization. Therefore, the higher heating values of oil fractions were decreased.The wet-decomposition process can be catalyzed by several metals involved in the sludge, such as Ni, Ca, Cr, Cu, Fe, Zn, and alkaline-earth metal, etc. The addition of catalysts didn’t improve the wet-decomposition process significantly. The liquid products were analyzed by the GC-MS and FTIR, which indicated that the esters were the main compounds. It was shown by those results that the wet-decomposition of sludge could be a promising route for the production of bio-diesel. Howver, it should be noted that nitrogenous and metal compounds must be removed before wet-decomposition, which could limit the application of that technology.The economic advantage of biomass wet-decomposition is that the raw material doesn’t need be dried before operation. However, presently, that process cann’t be operated continuously as the high pressure inside. A continue procedure was required by the industrial application. In this study, a new technology was investigated for industrial research, including torrefaction in fluidized bed and torrefied sawdust pelletization. The advantage of that technology is that the fluidized bed is a potential reactor which can be operated continuously with great mass and heat transfer ability. The typical batch fluidized bed was modified in this study. The sawdust could be fluidized in that reactor. The properties of torrefied sawdust were investigated under different torrefaction temperature and residence time, including weight loss, heating value, energy yield, energy density, particle size distribution, bulk density, and moisture absorption, etc. It was shown by the results that the weight loss and heating values of torrefied sawdust could be increased with increasing temperature and residence time, while energy yield and moisture absorption had the opposite trend. The energy density was enhanced with increasing residence time. The lowest bulk density was obtained at the condision with higher temperature and shorter residence time. The reasons for most results were focused on the decomposition of hemicellulose and lignin during the torrefaction. Hemicellulose is the active compound in sawdust. Most of hemicellulose was decomposed in the first30minutes of the torrefaction. However, lignin is a less active compound compared with hemicellulose. The slow decomposition of lignin was operated in the whole process of torrefaction.The torrefied sawdust should be compressed into small pellets, which can be transported, reserved and application more easily. The pelletization energy consumption, moisture absorption and hardness of pellets were investigated in this studv. During the pelletization, the compression energy consumption was increased with increasing the decomposition of lignin. Lignin is the natural stiffener in sawdust. Lignin was decomposed into char in the torrefaction. Meanwhile, the densities of pellets were reduced with increasing the torrefaction temperature and residence time. It was shown by those results that the further torrefied sawdust became more brittle and less plastic.However, according to the further results, the moisture absorptions of pellets from torrefied sawdust were significantly lower that those of raw sawdust pellets. The moisture absorptions of pellets from torrefied sawdust were decreased with increasing torrefaction temperature and torrefaction residence time. Hemicellulose with high moisture absorption ability was decomposed further at higher torrefaction temperature with longer torrefaction residence time. The natural structure of lignocellulose was destroyed, resulting in the decrement of moisture absorption.Meanwhile, compared with the moisture absorption of torredied sawdust, the moisture absorptions of pellets made of torredied sawdust with same torrefaction condition were lower. It was indicated that the structure of sample affected the moisture absorption. The moisture absorption was reduced during the compression.The Meyer hardnesses of pellets of torrefied sawdust were lower than those of raw sawdust pellets, as the decrement of lignin amount during the torrefaction. The Meyer hardnesses of pellets, which made of torrefied sawdust at higher torrefaction temperature and shorter residence time, were lower than those made of torrefied sawdust at lower torrefaction temperature and longer residence time. It can be due to that torrefaction temperature is the primary parameter compared with residence time.In this study, the wet-decomposition and dry-decomposition of biomass were investigated, in order to identify the effects of key parameters and mechanism in the decomposition process. The roles of synergistic solvents and hydrogen-donor were shown with the comparisons of the effects of key parameters. Different wet-decomposition products can be obtained from different feedstocks with different wet-decomposition solvents. In this study, several basic results were provided for the future industrial application. The fluidized bed was introduced into the production of biomass solid products without procedure of solid products separation. The scope of torrefaction was expanded for the industrial application in the near future.