| This paper was investigated on anaerobic digestion(AD) of Eupatorium adenophorum Spreng(ES) to produce biogas and focus on the potential and change of harmful substances on the dry fementation process, simultaneously, preparation biochar by anaerobic digestion residue(ADR) to implementation of terminal resource processing. According to experiments results are as follow:1) Effects of ratio of dung to straw, digestion concentration and inoculum concentration on biogas yield were investigated by orthogonal experiment. The results showed that the factor order of primary-secondary was following:digestion concentration>inoculum concentration>ratio of dung to straw. The optimum conditions of dry digestion to producing biogas for ES mixed cow dung was ratio of dung to straw 2:1, digestion concentration 20% and inoculum concentration 30%. Under the optimum technological conditions, the gas production rate of TS and VS was 123.05mL·g-1 and 164.56 mL·g-1, respectively. The average content of methane was 57.13%, the highest removal rate of TS and VS was 61.65% and 49.57%.2) Production biogas by four drying processes ES mixed pig manure(PM) with ratio of dung to straw 2:1, digestion concentration of 20%, inoculum concentration of 30%. The results manifested that XZ can be use with PM to produce biogas on account of it short digestion time and running well, TS and VS potential was 194.96 mL·g-1 and 240.11 mL·g-1 higher than other groups. The average methane content was up to 65%. The cumulative VFAs content decreased with ammonia nitrogen content. It was conducive to the production of methane when ammonia nitrogen content up to 4980 mg·L-1. Tannins decreased but coumarins were rising after AD and tannins degradation rate maximum value was 84.46%, coumarins growth 9.6 times.3)ES batch AD to produce biogas with digestion concentration was 8% results were as follows:TS and VS degradation rate is greatly higher than DF can reach 81.12% and 44.31% but daily production was poor and unstability. The SEM shows that ES structure changes were minor and lignin decreased most. The highest ammonia nitrogen content was 1056 mg·L-1. It was beneficial for AD to produce biogas. Tannins and coumarins decreased after AD and decline of 89.39% and 94.12%, respectively.4) Preparation biochar at low temperature pyrolysis from ADR turned out that: The highest biochar yield was 60.01%, while the highest caloric value was19.76MJ·kg- 1 at 400℃. Scanning Electron Microscope (SEM)-Energy Dispersive Spectrometer(EDS) analysis directly shows content of C and O elements in biochars. Fourier-Transform Infrared Spectroscopy(FTIR) analysis in the range of 400～4000cm-1 results show that water and semicellulose and other substances first carbonation, lignin carbonization began in 350℃ on account of AD reduce the carbonization temperature, a large number of C was accumulation in the stage. The curves of DTA with different heating rate (5℃/min,10℃/min,20℃/min) indicated that pyrolysis biochar through two stages mainly which low boiling point substances pyrolysis at 240～350℃ and thermal absorption to pyrolysis high boiling point matter above 450℃ Therefore,400℃ was ideal temperature to preparation biochar at low temperature pyrolysis from ADR.Above all, this paper showed an effective way to realize ES resource utilization that produce biogas by anaerobic digestion mixed livestock manure. Preparation biochar at low temperature pyrolysis from ADR reduce negative effect on environment and convert waste to energy.
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