原位固氮剂在污泥堆肥过程中保氮机制  

Nitrogen retention mechanism of in-situ nitrogen fixing agent in sludge composting process

作　　者：李云蓓 刘婷婷 姜继韶 吕景花 LI Yunbei;LIU Tingting;JIANG Jishao;LYU Jinghua(School of Environment,Henan Normal University,Xinxiang 453007,Henan,China;Key Laboratory of Yellow River and Huai River Water Environment and Pollution Control,Ministry of Education,Xinxiang 453007,Henan,China;Henan Key Laboratory for Environmental Pollution Control,Xinxiang 453007,Henan,China)

机构地区：[1]河南师范大学环境学院,河南新乡453007 [2]黄淮水环境与污染防治教育部重点实验室,河南新乡453007 [3]河南省环境污染控制重点实验室,河南新乡453007

出　　处：《化工进展》2020年第7期2876-2883,共8页Chemical Industry and Engineering Progress

基　　金：国家自然科学基金(51508167,41805123);河南省高等学校重点科研项目(16A560022,17B61006);河南师范大学博士科研启动课题(5101219170108,5101219170113);河南师范大学青年科学基金(2016QK18)。

摘　　要：高温好氧堆肥技术虽然可有效处理有机固体废物,但常常会释放大量的氨气和造成氮素损失。本文以硫酸镁、磷酸二氢钾、硫酸镁+磷酸二氢钾(分别记为MgSO4、KP和KPM处理组)为原位固氮剂,污泥和木屑为原料,进行高温好氧堆肥试验,研究以上原位固氮剂对污泥堆肥过程中的氨气挥发和氮素损失的影响。结果表明,硫酸镁(MgSO4)对物料pH有显著的降低效应,添加硫酸镁使堆体高温期pH降低至8.17,低于硫酸镁+磷酸二氢钾(KPM)组(8.55)和对照(CK)组(8.90)。与CK相比,MgSO4和KPM的NH3累积释放量分别降低了34%和28%,反而KP组增加了35%。对比不同条件下XRD图谱可知,MgSO4的固氮效应并不是由于MgNH4PO4·6H2O的生成,而是由于其对pH的降低效应造成的。堆肥结束后,除了KP组,各处理条件下的种子发芽率值(germination index,GI)均不会对后续使用带来不利影响。Although high-temperature aerobic composting technology can effectively treat organic solid waste,it often releases a large amount of ammonia and causes nitrogen loss.In the present study,magnesium sulfate,potassium dihydrogen phosphate and magnesium sulfate+potassium dihydrogen phosphate(marked as MgSO4,KP and KPM treatments)were used as nitrogen fixing agents during sewage sludge composting with sawdust as bulking agent.The effects of the above nitrogen fixing additives on ammonia volatilization and nitrogen loss during sludge composting were investigated.The results showed that magnesium sulfate(MgSO4)could significantly reduce pH value.The pH value of thermophilic stage in MgSO4 treatment was 8.17,which was lower than that of the KPM(8.55)and the control treatment(CK)(8.90).Compared with CK treatment,addition of MgSO4 reduced the total NH3 emission by 34%and 28%in the KPM treatment.However,the total NH3 emission increased by 35%compared with CK treatment.However,according to the result of XRD,no struvite was formed during the present composting process.The nitrogen retention mechanism of MgSO4 in the present study was mainly caused by the decrease in pH value.After composting,the GI values of all treatment can meet the need for agricultural use except for KP treatment.

关 键 词：污泥 固氮剂 好氧堆肥 氨气 氮素损失 

分 类 号：X703[环境科学与工程—环境工程]