Simulation Experiment of the Anaerobic Degradation Law of Municipal Solid Waste

Using four sets of self-designed devices, the simulation experiment was carried out, which lasted 11 months. By monitoring the content of volatile solid, fats, crude fiber and humic acid, the anaerobic degradation law of the organic fraction of municipal solid waste (OFMSW) was studied. The results show that: (1) OFMSW degradation amount takes up 82.3% of the total at the acidification stage, so the acidification stage is the main period of OFMSW degradation. (2) Methanation inhibits the degradation of fats strongly, and the fats degradation rate decreases from 4.4 g-kg^-1-d^-1 to 0.4 g-kg^-1-d^-1 rapidly at the methanation stage. (3) There is great difference among the degradation degree of hemicellulose, cellulose and lignin, and their degradation rates are 66.9%, 51.6% and 7.3% respectively. Hemicellulose/lignin and cellulose/lignin decrease linearly with degradation time, which can be used as a stabilization evaluation index in the process of OFMSW degradation. (4) LFG disturbance action and pH increase are two possible reasons to lead the total extractable hymatomelanic acid and humus acid decrease rapidly along with LFG production increase.