| With the rapid development of livestock production, livestock waste is becoming a big concern of China as well as in the world. Currently there are very narrow choice of waste treatment technologies, some technologies even cause second pollution. The pyrolysis technology can produce bio-oil, pyrolysis gas, and carbon while environment load from livestock wastes was relieved. The thesis was conducted to investigate the pyrolysis characteristics of livestock waste based on the measurement of chemical ingredients of livestock manure, a bench-scale fluidized bed reactor was designed to pyrolyze livestock manure, the effects of pyrolysis temperature, partical size of swine manure, and feeding speed on pyrolysis product were studied. Results showed:Cellulose contents of oven-dried manure ranged from 3.75% to 20.92%, which were lower than those of straw. The herni-cellulose content of livestock manure was similar to that in straw. The lignin contents were 7.57%±4.09%, 13.39%±2.57%, 23.72% and 26.28% for swine manure, chicken manure, cattle manure and goat manure, respectively, with the reference lignin content of 16.70%～11.90% for straw. The volatile content, fixed carbon and ash in air-dried livestock manure averaged 63.31%, 13.00% and 20.97%, respectively. The low heating value of swine manure was 17.12MJ·kg-1, which was slightly higher than that of corn stalks, the heating values of cattle, chicken and goat manure were lower than straw, but all the heating values were over 11 MJ·kg-1. The above data showed that air-dried livestock manure could be used as a raw material for pyrolysis liquefaction.The thermo-gravimetric balance coupled with a Fourier Transform Infrared spectrometry (TG-FTTR) experiments revealed a same trend for pyrolysis processes with different livestock manure: the pyrolysis process was slow when the temperature was lower than 200°C, fierce reaction happened when temperature rose between 200 to 450°C, then the pyrolysis process slowed down again when temperature exceeded 500°C, the mass loss accounted for 63.13%～76.13% between temperature range of 225～345°C. The activation energy values and frequency factor varied with different livestock manure, the activation energy values ranged from 65 to 180kJ·mol-1 while the frequency factor varied from 104min-1 to 10-1min-1 The pyrolysis gases, mainly H2O, CO, CO2和CH4, were produced when temperature was in between 250500°C with the highest production in 350°C for swine manure, chicken manure, goat manure and 500°C for cattle manure.The fast pyrolysis experiments results revealed that temperature was an important parameter for pyrolysis of swine manure. The carbon yield decreased while gases products increased with temperature rise. The bio-oil product showed maximum value in the temperature of 450°C. When the particle size of swine manure were no more than 1 mm, no significant effects on bio-oil production was observed, but increasing feed speed could raise bio-oil production. The N content in solid product was pretty lower than that in raw material, but solid product contained most of the K, P, Cu and Zn.
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