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The object of this work is to reduce carbon dioxide emission and produce renewable liquid fuel (bio-oil) from locally produced rice husk by pyrolysis in a discontinuity feeding and fluidized bed reactor. The experiments are carried on at different temperatures ranging from 723K to 923K. At 773K, the yields of bio-oil, solid and non-condensable are 53.8wt‫1.91ޔ‬ wt and 27.1wt%, respectively based on rice husk. The elemental analysis, density, PH, viscosity and lower heating value of bio-oil are determined, and then the chemical composition of the pyrolysis oil is studied using GC-MS techniques. To speed up bio-oil's commercialization, the proportion and physicochemical property of the production of emulsions from bio-oil and diesel fuel are investigated. The result shows that emulsion method is a more convenient and cheaper bio-oil utilization approach.

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In-depth understanding and analysis of turbulent convection heat transfer of supercritical water under semicircular heating conditions play a major role in system design and security. The inaccurate numerical results on simulating the buoyancy effect under deterioration heat transfer cases are partly attributed to the invalidity of the turbulent model. An improved turbulence model, which is validated suitable to three-dimensional model, is adopted in the present paper to numerical simulated flow and heat transfer in a vertical tube under semicircular heating condition. Heat transfer deterioration phenomenon occurs under semicircular heating condition, while the degree of deterioration is weakened due to the influence of variable physical properties and buoyancy effect. The velocity profile is distorted into “M-shape” in the heating side and present parabolic distribution in the adiabatic side, leading to different deterioration mechanisms under semicircular heating condition compared with uniform heating. The larger density difference between the heating side and the adiabatic side increases the shear stress production of turbulent kinetic energy; turbulent development is much faster recovery than the phenomenon in uniform heating condition. The results show that the semicircular heating condition can effectively alleviate the degree of heat transfer deterioration in a vertical tube.

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Pyrolysis processes of typical biomass, such as corn stalk and birch chips, were investigated by thermogravimetric analysis (TGA). The apparent activation energy and pre-exponential factor were calculated with the adoption of the improved Coats-Redfern integral method, 46 types of common mechanism functions, and the least square and iterative methods. By applying basic parameters of biomass pyrolysis, a reaction rate constant, activation entropy and activation enthalpy, activation Gibbs free energy, and the steric-hindrance factor were all calculated. Results showed that biomass pyrolysis can be divided into two primary reaction zones (Event 3 and Event 4). Event 3 is focused by cellulose and hemicellulose. Event 4 is oriented by lignin and cellulose. The thermogravimetric curves of the two biomass types under carbon dioxide and nitrogen atmospheres were roughly similar. The reaction mechanism function is 1 -. It is possible to use activation entropy to represent the pre-exponential factor and to use the steric hindrance factor to predict the reaction rate.