中文摘要：

为了提高沼气反应器对发酵原料利用率，缩短发酵周期，提高产气率，该文试验研究了镁离子添加量分别对以莴笋皮和马铃薯皮为发酵原料的抗结壳沼气反应器产气性能的影响。结果表明：以莴笋皮为发酵原料，每升沼液中镁盐最佳添加量为0．30g，池容产气率为0．398m3／（m^3·d），发酵后期甲烷浓度稳定在70％左右，总产气量提高了71．4％；以马铃薯皮为发酵原料，每升沼液中镁盐最佳添加量为0．10g，池容产气率达到O．804m^3／（m^3·d），发酵后期甲烷浓度稳定在68％左右，总产气量提高了41．6％。因此适量的镁离子添加量能缩短沼气反应器的发酵启动时间，促进甲烷合成，显著提高反应器的产气性能。

英文摘要：

In order to improve utilization rate of raw materials, shorten period of fermentation and increase gas production rate, the effects of magnesium sulfate on biogas production performances were investigated in an anaerobic digester with anti-scum device using asparagus lettuce peelings and potato peelings. Results showed that the optimal addition amount of magnesium ions with the asparagus lettuce peelings and potato peelings were 0.30 g and 0.10 g per liter gas slurry, respectively. The cumulative total amounts of biogas were enhanced by 71.4% and 4 1.6%, compared to the comparison. Correspondingly, with the asparagus lettuce peelings and potato peelings the highest volumetric production rate of biogas reached 0.398 mV（m^3·d） and 0.804 m^3/（m^3·d）, and the methane content of biogas maintained at about 70% and 68% in the end of the biogas fermentation, respectively. The results indicated that adequate magnesium ions supplemented could significantly shorten the startup time of fermentation and enhance the daily biogas productivity and methane content ofbiogas.