改性膨胀蛭石覆盖对沼液贮存氨气和温室气体排放影响  

Ammonia and greenhouse gas mitigation from biogas slurry storage using a modified expanded vermiculite cover

作　　者：王悦[1] 刘婧怡 张佳男 郭赫 朱志平[3] 李新荣[1] 邹国元[1] WANG Yue;LIU Jing-yi;ZHANG Jia-nan;GUO He;ZHU Zhi-ping;LI Xin-rong;ZOU Guo-yuan(Institute of Plant Nutrition and Resources,Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097,China;Urban Construction School,Beijing City University,Beijing 101399,China;Institute of Environment and Sustainable Development in Agriculture,Chinese Academy of Agricultural Sciences,Beijing 100081,China)

机构地区：[1]北京市农林科学院植物营养与资源研究所,北京100097 [2]北京城市学院城市建设学部,北京101399 [3]中国农业科学院农业环境与可持续发展研究所,北京100081

出　　处：《农业环境科学学报》2021年第4期902-912,共11页Journal of Agro-Environment Science

基　　金：国家重点研发计划项目(2018YFC0213303);北京市农林科学院创新能力建设专项项目(KJCX20200433);北京城市学院2019年度实培计划项目;北京市新世纪百千万人才工程(2019A08);中国农业科学院国际农业科学计划(CAAS-ZDRW202110)。

摘　　要：畜禽养殖污水贮存是重要的氨气(NH_(3))和温室气体(GHG)排放源,本文以奶牛场沼液贮存气体排放为研究对象,探索采用不同酸性盐溶液改性膨胀蛭石后再覆盖对气体减排效果的影响。研究比较了硫酸铜改性蛭石(CuSO_(4)-VM)、氯化锌改性蛭石(ZnCl_(2)-VM)、未改性蛭石(UN-VM),以及不加覆盖(CK)4种条件下奶牛场沼液贮存32 d过程中NH3、甲烷(CH_(4))、二氧化碳(CO_(2))和氧化亚氮(N2O)排放情况,分析了不同改性处理蛭石覆盖对各气体排放的影响及其原因。研究发现,改性处理后可使蛭石覆盖对NH3和CH4的减排效果增强,ZnCl_(2)-VM、CuSO_(4)-VM和UN-VM对NH3减排效果分别为90%、81%和34%;对CH4减排效果分别为58%、21%和14%;对于CO_(2)的减排效果分别为-8%、2%和20%。蛭石改性后呈酸性,其覆盖后对污水的酸化是NH3减排效果提高的关键因素;而蛭石改性后产生的对污水有机物的絮凝作用以及形成的良好覆盖是促使CH4减排效果提高的主要原因。但是酸性的提高会降低改性蛭石覆盖对CO_(2)的减排效果。研究中较低的温度条件造成N2O排放较低,不能判断改性对N2O排放的影响。研究表明,改性膨胀蛭石覆盖可能是一种有效的污水贮存NH_(3)和CH_(4)的减排方法。Animal slurry storage is an important source of ammonia(NH_(3))and greenhouse gas emissions.This study aimed to explore the effects of modified vermiculite covers on gas mitigation from dairy slurry storage.Four treatments of dairy biogas slurry storage were set in this study,including two treatments using expanded vermiculite modified with acid-metal solutions,namely copper sulfate-modified vermiculite(CuSO4-VM)and zinc chloride-modified vermiculite(ZnCl_(2)-VM),and an unmodified vermiculite cover(UN-VM)and the control with no cover(CK).The emission concentrations of NH_(3),methane(CH_(4)),nitrous oxide(N2O),and carbon dioxide(CO_(2))from 32 d of slurry storage were measured continuously.The mitigation effects(MEs)for each specific gas under different cover treatments were compared,and the reasons were analyzed.The results showed that the modification of vermiculite enhanced the MEs on NH_(3)and CH_(4).ZnCl_(2)-VM,CuSO4-VM,and UN-VM reduced the NH_(3)emissions by 90%,81%,and 34%,respectively;the corresponding MEs on CH_(4)were 58%,21%,and 14%,and those on CO_(2)were-8%,2%,and 20%.The modified vermiculite became acidic,which resulted in a slurry acidification effect when applied to the slurry surface,thereby contributing to the high ME on NH_(3).The flocculation of the organic matter in the slurry owing the added modified vermiculite and the good coverage formed on the slurry surface led to the increased reduction in CH_(4)emissions.However,the increase in acidity after the modification reduced the ME on CO_(2),and the CO_(2)emissions in ZnCl_(2)-VM increased.The low temperature conditions in the study resulted in little N2O emissions during the storage period;therefore,the effect of modification on N2O emissions could not be judged in this study.In summary,the covering of slurry using modified vermiculite may be an effective NH_(3)and CH_(4)mitigation method.

关 键 词：氨气 温室气体 减排 改性膨胀蛭石 覆盖 

分 类 号：X71[环境科学与工程—环境工程]