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In this paper, water hyacinth was taken as the only substrate for anaerobic fermentation under the principles of dry anaerobic fermentation with the aim to find the superiority of dry anaerobic fermentation than the wet-phase. Then, an independent experiment of dry anaerobic fermentation was studied, so as to find the principle, gas production and gas quality standards. Explore the process route and a new method of comprehensive utilization of water hyacinth.In the experiment, the basic properties of the raw material of water hyacinth including elemental analysis, main ingredients analysis, determination of calorific value,etc were measured. Then, wet and dry anaerobic fermentation comparative experiment study were taken under the same experimental conditions. The results shows that: start-up time of dry anaerobic fermentation than wet anaerobic digestion delay 3~5 days, dry anaerobic fermentation can match the level to wet anaerobic digestion in the aspect of gas production level, gas quality, average methane concentrations. However, dry anaerobic fermentation have higher superiority than wet anaerobic digestion in the aspect of raw material utilization, cumulative biogas production for 30 days, Chi Yung rate, respectively, 1.5, 10, 5 times than the wet. Whar’s more, biogas slurry residue displacement is just 10% of the wet anaerobic digestion. Taken together, dry anaerobic fermentation have relatively high compared advantages. Finally, an independent experiment of dry anaerobic fermentation was studied, The results shows that: start-up time of dry anaerobic fermentation is about 7days, alkaline pretreatment can effectively avoid the phenomenon of fermentation severe acidification in early stage which can improve the stability of the fermentation system, feed rate and temperature have positively effects the result on the actual gas production. The optimum pH value is 7.8, optimum C / N is 20, the actual gas production level is 403mL/gTS.This subject obtain results that the main impact factors affect the fermentation process of water hyacinth dry anaerobic methane fermentation. Take 100m3/d program to simulate actual water hyacinth biogas project, it’s process steps, approach routes, and design ideas. Provide real templates support and basic datas for its engineering application, as well as a new method of comprehensive utilization of water hyacinth.
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