Studies On The Influencing Factors Of Two-phase Anaerobic Digestion Of Food Waste And Sewage Sludge

With the development of economic and improvement of the sewage treatment requirements, a lot of food waste and sewage sludge generated. How to treatment the two kinds of solid wastes in an efficient and low-cost way become an important research projects in domestic and overseas. Combined with the characteristics of food waste and sewage sludge and on the basis of previous studies, proposed a two-phase mesophilic anaerobic digestion of food waste and sewage sludge. The process can make full use of the organic in food waste and the active microorganisms in sewage sludge to achieve high speed and efficiency. The results show that:1) The mixed ratio of1:4works well in the two-phase mesophilic anaerobic digestion of food waste and sewage sludge, Effectively producing the hydrolysis reaction and methanogenic reaction. It shows that a two-phase mesophilic anaerobic digestion of food waste and sewage sludge process methane is feasible.2) The dosing rate has some influences on the secondary fermentation reaction. Under the condition mixed ratio of1:4,8%,10%and12%secondary dosing rate the SCODcr removal rates are71.49%、73.22%and69.46%; the total removal rates of VS are60.50%、73.17%and59.79%; methane production are181.18mLCH4/(gVS-d)、570.58mLCH4/(gVS·d)�'�213.73mLCH4/(gVS·d). It can be drawn that under the mixed ratio of1:4, the dosing rate of10%is best.3) The research of the mixed ratio of1:3and1:4under10%secondary dosing rate shows that:when the mixed ratio is1:4, SCODcr is removed at the day of40, the removal rate of VS is73.17%, the gas production of secondary reaction is697.65mL/(gVS·d), the gas in the first reaction is mainly H2, and CH4in the secondary reaction. When the mixed ratio is1:3, SCODcr is not removed through the fermentation, the removal rate of VS is49.74%, the gas production of second reaction is469.60mL/(gVS·d), the gas in the first and second reactions is almost H2. It can be drawn that under10%secondary dosing rate, the mixed ratio of1:4is best.4) The research of comparing the mesophilic digestion and thermophilic digestion shows that:under the mixed ratio of1:4, secondary dosing rate of10%, the digestion effection of mesophilic digestion is similar with thermophilic digestion and the needed heat of degradation of1gVS is less. So the mesophilic digestion is better under1:4mixed ratio and10%secondary dosing rate.