欢迎访问《环境科学学报》编辑部网站！

快速检索			高级检索

研究报告

Evaluation of high-solids anaerobic digestion process for converting excess sludge to biogas

摘要：应用高固体浓度厌氧消化工艺在中温(35±1)℃条件下,考察了进料总固体(TS)含量为17%的污泥在5L反应器中批式厌氧消化产沼气的发酵过程,并探讨了高固体浓度厌氧消化工艺转化污泥产沼气的可行性.结果表明,沼气和CH₄的累积产量在整个厌氧消化期间(73d)经历产气高峰、相对稳定和结束3个阶段,累积产气量分别达121.3L和80.3L,且在产气相对稳定阶段,CH₄的含量保持相对稳定,平均为70.7%;虽然总酸、乙酸、丙酸和氨氮在消化阶段最高分别达9.5g·L^-1、4.8g·L^-1、2.6g·L^-1和3653mg·L^-1,但沼气和甲烷的产量在厌氧消化过程中并未受到明显的影响.同时,应用高固体浓度厌氧消化工艺可显著提高有效容积沼气产率和有效容积CH₄产率,它们在厌氧消化期间的产率平均分别可达0.498L·L^-1·d^-1与0.330L·L^-1·d^-1,且厌氧消化结束后总固体和有机质(VS)去除率分别为44.2%和67.3%.

Abstract：Laboratory-scale evaluation of a high-solids anaerobic digestion process for converting excess sludge to biogas was performed in this study.The batch experiment was carried out in a developed anaerobic reactor(5.0 L),which operated at mesophilic(35±1)℃ and high-solids(17% total solids) conditions.Excess sludge exhibited a methanogenic pattern including fast biogas production phase,relatively stable phase and final phase through the whole experimental period(73 days) and this gave cumulative biogas of 121.3 Land cumulative bio-methane of 80.3 L.The content of bio-methane stayed relatively stable during the relatively stable operation phase,and its mean value accounted for 70.7%.Although total volatile fatty acids,acetic acid,propionic acid and ammonia nitrogen significantly increased to 9.5 g·L^-1,4.8 g·L^-1,2.6 g·L^-1 and 3653 mg·L^-1,respectively,they had no obvious impact on the production of biogas and bio-methane during the anaerobic digestion.The production rate of biogas and bio-methane expressed as the space-time yield(gas volume/reactor volume/time) could be significantly enhanced with the high-solids anaerobic digestion process;and they respectively reached 0.498 L·L^-1·d^-1 and 0.330 L·L^-1·d^-1 with 44.2% reduction of total solids and 67.3% reduction of total volatile solids after the anaerobic digestion.