调理剂种类对贮存污泥生物干化的影响研究

Effect of bulking agents on biodrying of storage sludge

采用自主设计的贮存污泥生物干化试验装置,研究了不同调理剂(啤酒糟、稻壳、木屑、塑料环)对贮存污泥生物干化效果的影响,试验过程中设置了C1(稻壳)、C2(木屑)、C_(3)(啤酒糟)、C4(塑料环)、C5(对照)共5个试验堆体,试验采用10 min开、20 min关的间歇通风方式,通风量为1.4 L/(min·kg干物质),试验周期为18 d,结果表明C_(3)堆体的生物干化效果最佳,其温度最高可达62.5℃,含水率可由70.98%降至56.36%,挥发性固体(Volatile Solid,VS)由64.01%降至50.11%,溶解性有机物(Dissolved Organic Matter,DOM)下降幅度最大,其中溶解性有机碳(Dissolved Organic Carbon,DOC)由63.35 g/kg降至24.25 g/kg,溶解性有机氮(Dissolved Organic Nitrogen,DON)由14.92 g/kg降至8.67 g/kg;其次为C1、C2、C4及C5,说明贮存污泥生物干化过程中需添加调理剂,啤酒糟作为调理剂的效果最好,稻壳、木屑次之,塑料环等无机调理剂不适合作为调理剂。此外,不同调理剂作用下生物干化系统的w(DOC)/w(DON)均逐渐降低,如C1堆体w(DOC)/w(DON)由4.29降至2.63,C_(3)堆体w(DOC)/w(DON)由4.24降至2.52,C4堆体w(DOC)/w(DON)由4.25降至3.93,说明生物干化可在一定程度提高干化物料的稳定性。

A self-designed experimental device was used to study the effects of different bulking agents(beer lees,rice husk,sawdust,and plastic ring)on the biodrying of storage sludge.Five experimental reactors were set up in the experimental process,including C1(rice husk),C2(sawdust),C_(3)(beer lees),C4(plastic ring),and C5(control).During the experiment,the ratio of storage sludge to bulking agent was 5∶1(w/w,wet weight),the ventilation mode was intermittent ventilation with 10 min on,20 min off and the ventilation rate was 1.4 L/(min.kg DM).The period of biodrying was 18 days,and the sampling frequency was 3 days.The results show that the effect of C_(3) reactor is the best,the maximum temperature can reach 62.5℃,the moisture content reduces from 70.98%to 56.36%,the volatile solid(VS)reduces from 64.01%to 50.11%,and the decrease range of dissolved organic matter(DOM)is the largest,in which dssolved organic carbon(DOC)decreases from 63.35 g/kg to 24.25 g/kg and dissolved organic nitrogen(DON)decreases from 14.92 g/kg to 8.67 g/kg,followed by C1,C2,C4 and C5,indicating that bulking agents are needed in the process of biodrying of storage sewage.The results reveal beer lees are more suitable for the biodrying of storage sluage,followed by rice husk and sawdust.Inorganic conditioner such as plastic ring is not suitable as bulking agent.Additionally,the w(DOC)/w(DON)of different biodrying systems decreases gradually under the action of different bulking agents.For example,the w(DOC)/w(DON)of C1 decreases from 4.29 to 2.63,the w(DOC)/w(DON)of C_(3) decreases from 4.24 to 2.52,and the w(DOC)/w(DON)of C4 decreases from 4.25 to 3.93,indicating that biodrying can improve the stability of dried materials to a certain extent.The results demonstrate that the inorganic bulking agent is not suitable as a bulking agent,and beer lees are more suitable as bulking agents.