3MW集中式热电肥联产沼气工程设计与建设

Design and construction of 3MW centralized biogas plant combined with heat,power and fertilizer production

山东民和牧业股份有限公司利用所属23家养殖场的鸡粪和污水作为沼气发酵原料,投资建设大型畜禽养殖场集中式沼气发电工程。原料经水解除砂工艺将鸡粪中的砂砾除去,保证发酵效率;采用中温(38℃)发酵工艺,产沼气30 000 m3/d;采用高效率低运行成本的生物脱硫工艺,将沼气中的H2S含量降至200×10-6以下;经净化的沼气在双膜干式贮气柜中贮存,供给热电联产的发电机组使用,发电量60 000 kWh/d,机组余热用于冬季发酵系统自身增温;发酵后的沼液用作周围葡萄、苹果及玉米地的有机肥料。项目实现了温室气体减排84 882 t CO2当量。文章介绍了该沼气发电工程的工艺特点和技术要点,为同类型沼气发电工程设计和建设提供参考。

Shandong Minhe Poultry Co., Ltd is a large-scale enterprise for breeding, foodstuff and fertilizer production. Minhe has built a large-scale centralized biogas plant, which utilizes the chicken manure and waste water from their 23 chicken farms to produce biogas since the year 2007. The sand in the manure can be removed by hydrolysis process to guarantee a higher digestion rate. Around 30000 m3/d of hiogas can be gained by mid-temperature （38 ℃） mesophilic digestion. And the biological desulphurization featured by high efficiency and low cost can reduce H2S in the biogas to a level below 200 ppm. Besides, after purification, the biogas stored in the double membrane biogas tank will be utilized for power generation. Around 60 000 kWh/d of power can be produced by the CHP engine, while the excess heat can be used for heating the digesters. The bio- liquid can be used as organic fertilizer for grape, apple and corn farmland. Meantime, this project can reduce all together 84 882 tons of CERs for our environment. This paper will introduce the characteristics of these processes and the key points in this plant, which also can be the reference for other similar cases.