Experimental Research On Biomass Pyrolysis Liquefaction

The exploitation and utilization of biomass energy is an effective method for relieving the pressure from conventional energy shortage and environment and establishing the sustainable energy system. The technology of biomass pyrolysis can convert low-quality biomass energy into bio-oil that has the character of high-quality, high energy density, cleanness and zero carbon dioxide emission. This not only can solve the problem of unreasonable energy utilization and environmental pollution during the townified course and enhance the utilization efficiency of biomass energy in Chinese rural area, but can improve the unstable condition in energy and economy which is caused by abundant petroleum import in China.This paper summarized the research status in biomass pyralysis liquefication all over the world, and on this basis, set up one single-tower fast pyralysis liquefication system and debugged it; examined and improved the transporting unit, made experimental analysis on the accumulation characteristic of biomass materials and on this foundation, studied the characteristic of biomass transporting system and presented one prediction method of biomass transportation capacity; carried on the visible experimental research on biomass fluidization characteristic inside the pyrolysis reactor, established one gas-solid excursion flow model, provided one method of calculating the relative velocity between biomass grains and the fluid (minimum carry-away velocity for short) and analyzed the influence laws of various parameters (grain diameter, grain density, fluid temperature, average interspace ratio, etc.) on the minimum carry-away velocity theoretically; studied the fluidization characteristic of the quartz sand and several biomass materials by experiment and found that the experimental value and theoretical value of minimum carry-away velocity approximate well, which indicates that the drifting flow model presented in this paper can better describe the flow state in the reactor tower; analyzed the heat transfer process inside the tower and simplified the complicated multiphase heat transfer (among biomass grain, quartz sand, fluidization gas, etc.) into the two-phase heat transfer between biomass grain and the environment around it, finally finding out the calculation method of heat transfer time during which the center of biomass grain can reach full pyrogenation (temperature); according to the analysis results of the fluidization characteristic and heat transfer process, determined the experimental parameters of biomass pyralysis liquefication; carried on the heat...