膜覆盖好氧堆肥的冷凝液和渗滤液二次污染防治设计

为提高膜覆盖好氧堆肥系统在南方潮湿多雨地区推广的适用性，解决冷凝液、渗滤液污染，本文对不同批次牛粪-秸秆混合物膜覆盖好氧堆肥的冷凝液进行了检测，对常规膜覆盖好氧堆肥发酵槽进行了二次污染防治优化设计。分析了常见做法的优缺点，设计了U型导流护套、组合式HDPE膜防渗底板、雨污分流系统，优化了并列槽渗滤液导排系统，提出了系统运行期间污染防治措施建议。结果表明，牛粪-秸秆混合物膜覆盖好氧堆肥冷凝液的PH为8.6~9.2，氨氮含量为17.9~196 mg·L-1、COD为102~230mg·L-1，硫化物含量为0.046~0.178 mg·L-1，PH、氨氮、COD指标超过了污水综合排放标准限值，不能直接排放。优化设计后的系统经工程实施检验可基本杜绝系统露天运行时的冷凝液、渗滤液的二次污染问题。但当堆肥处理量大、系统使用频繁时，建议设置遮雨棚以提高效率，降低劳动强度。

Design of secondary pollution prevention in aerobic compost system of membrane covering for condensate water and leachate

In order to improve the applicability of the aerobic compost system of membrane covering in the humid and rainy areas of the south, solve the pollution of condensate water and leachate. In this paper, the condensate of different batches of cow dung-straw mixture film-covered aerobic compost was tested, the conventional membrane covering fermentation tank has been optimized for the prevention of secondary pollution. analyzed the advantages and disadvantages of common practices, designed U-shape diversion sheath, combined HDPE film impervious baseplate, rain and sewage diversion system , optimized the method of diversion and drainage of leachate when multiple systems are set up in parallel, proposed pollution prevention measures during the operation of the system. The results showed that the pH of the aerobic composting condensate covered with the cow dung-straw mixture film was 8.6~9.2, the ammonia nitrogen content was 17.9~196 mg·L-1, the COD content was 102~230 mg·L-1, and the sulfide content was 0.046~0.178 mg·L-1. The PH, ammonia nitrogen, and COD indicators exceeded the comprehensive sewage discharge standard limit. Therefore, it cannot be discharged directly. The optimized design of the system can basically eliminate the secondary pollution problem of condensate and leachate during open-air operation of the system through project implementation inspection. However, when the amount of composting is large and the system is used frequently, it is recommended to set up a canopy to improve efficiency and reduce labor. intensity