摘要
为探究生物炭对发酵过程理化特性、水溶性有机物(DOM)组分以及重金属形态变化的影响机制,以猪粪和秸秆为原料,添加不同比例生物炭作为钝化材料开展好氧发酵试验。结果表明:发酵结束后生物炭添加量为0、5%、15%和25%处理的腐殖质类物质分别增加了22.69%、24.49%、25.32%和25.45%;各处理对重金属Cu、Zn、Pb、Cd的钝化效率分别为25.80%~47.00%、16.73%~31.34%、31.81%~57.68%和20.00%~71.47%,均使活性相对较高的吸附态向较为稳定的络合态和沉淀态转化;DOM组分、温度、pH、EC和含水率变化对重金属形态均有较大影响,其中富里酸和胡敏酸对可交换态Cu、Zn、Cd和Pb的影响显著,胡敏酸对重金属的络合起主要作用,pH对促进生物炭与重金属离子交换、共沉淀及重金属配合物的稳定性等具有较大的影响。研究表明,在猪粪好氧发酵过程中添加生物炭可促进DOM组分中的富里酸向胡敏酸转化,进而提高了腐殖质的稳定性和重金属的钝化效率。
The physical and chemical characteristics of the fermentation process,changes in the composition of dissolved organic matter(DOM),changes in the binding form of heavy metals,and the influence mechanism of biochar were investigated.Pig manure and straw were used as raw materials to which different proportions of biochar-used as a passivation material-were added to carry out aerobic fermentation experiments to analyze the physical and chemical properties associated with different fermentation times and DOM components and the influencing factors and mechanisms of heavy metal forms.Results showed that the contents of the humic substances in the 0,5%,15%,and 25%treatment groups increased by 22.69%,24.49%,25.32%,and 25.45%,respectively;they showed varying degrees of passivation effect on Cu,Zn,Pb,and Cd.The passivation rates were 25.80%~47.00%,16.73%~31.34%,31.81%~57.68%,and 20.00%~71.47%.The relatively more active adsorption state transformed to a more stable complex form and precipitation form.The change in DOM,temperature,pH,EC,and moisture content had significant effects on the form of heavy metals.Among them,fulvic acid and humic acid had significant effects on the exchangeability of Cu,Zn,Cd,and Pb.Humic acid played a major role in the complexation of heavy metals,and pH had a greater impact on promoting biochar and heavy metal ion exchange and co-precipitation and the stability of heavy metal complexes.These results indicated that adding biochar during the aerobic fermentation of pig manure can promote the conversion of fulvic acid to humic acid in the DOM component,thereby promoting the formation of stable humic substances and increasing the efficiency of heavy metal passivation.
作者
王鑫宇
张曦
丁京涛
沈玉君
孟海波
周海宾
程红胜
王健
李冉
WANG Xinyu;ZHANG Xi;DING Jingtao;SHEN Yujun;MENG Haibo;ZHOU Haibin;CHENG Hongsheng;WANG Jian;LI Ran(Academy of Agricultural Planning and Engineering,Ministry of Agriculture and Rural Affairs,Beijing 100125,China;Key Laboratory of Technology and Model for Cyclic Utilization from Agricultural Resources,Ministry of Agriculture and Rural Affairs,Beijing 100125,China)
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2021年第11期2372-2382,共11页
Journal of Agro-Environment Science
基金
北京市科委“北京市科技新星计划”项目(Z191100001119063)。
