摘要
为降低生活污泥中重金属迁移性和有效性,提高其利用率,以某市生活污水处理厂剩余污泥为研究对象,设置污泥单独堆肥为对照组,添加蚯蚓和不同比例玉米秸秆炭(0%、2%、4%、6%和8%),探究秸秆炭协助蚯蚓堆肥条件下污泥中重金属浓度及其有效态的时间变化规律。结果表明,随堆肥时间增加(0~30 d),污泥pH和总氮(TN)浓度先升高后降低,总有机碳(TOC)浓度逐渐降低,电导率(EC)先降低后升高,总磷(TP)和总钾(TK)浓度逐渐增加,堆肥结束时,pH、TOC浓度和TN浓度分别较初始值平均降低6.38%、20.24%和13.44%;重金属Cd、Zn和Pb浓度先降低后升高,Cu、Ni和Cr浓度先升高后降低;重金属Cd、Cu、Ni和Zn有效态浓度先降低后升高,Cr和Pb有效态浓度先升高后降低,堆肥10 d时,Cd、Cu、Ni和Zn有效态浓度较初始值降低最多,平均降低40.99%、30.65%、16.23%和3.17%。秸秆炭的添加能改善污泥弱酸性环境,提高TK浓度,降低EC和TOC、TN、TP浓度;污泥中重金属(除Pb外)浓度及其有效态(除Cu和Pb外)浓度均随秸秆炭添加比例的增加而降低。通过相关性和逐步回归分析得出,秸秆炭协助蚯蚓堆肥主要通过改变污泥pH及EC与TOC、TP浓度影响重金属有效态浓度,且添加8%玉米秸秆炭时污泥中重金属浓度和有效态浓度降低效果最佳。
In order to reduce the migration and availability of heavy metals in domestic sludge and improve its utilization rate,the residual sludge of a municipal domestic sewage treatment plant was taken as the research object,the sludge by composting alone was set as the control group,and the earthworms and different proportions of corn straw charcoal(0%,2%,4%,6%and 8%)were added,to study the time variation of heavy metal concentrations and their effective state in sludge under the condition of straw charcoal assisted earthworm composting.The results showed that with the increase of composting time(0-30 d),the pH and TN concentrations of sludge first increased and then decreased,the TOC concentration gradually decreased,the EC concentration first decreased and then increased,and the TP and TK concentrations gradually increased.At the end of composting,the pH,TOC and TN concentrations decreased by 6.38%,20.24%and 13.44%on average compared with the initial values,respectively.The concentrations of heavy metals Cd,Zn and Pb decreased first and then increased,while the concentrations of Cu,Ni and Cr increased first and then decreased.The effective concentrations of heavy metals Cd,Cu,Ni and Zn decreased first and then increased,and the effective concentrations of Cr and Pb increased first and then decreased.After 10 days of composting,the effective concentrations of Cd,Cu,Ni and Zn decreased the most compared with the initial values,with an average decrease of 40.99%,30.65%,16.23%and 3.17%,respectively.The addition of straw carbon could improve the weak acid environment of sludge,increase the concentration of TK,and decrease the concentrations of EC,TOC,TN and TP.The concentrations of heavy metals in sludge(except Pb)and their effective state concentrations(except Cu and Pb)decreased with the increase of the proportion of carbon added to straw.Through correlation and stepwise regression analysis,it was concluded that straw charcoal assisted earthworm composting mainly affected the effective concentration of heavy metals by changing the sludge pH and the concentrations of EC,TOC and TP,and the addition of 8%corn straw charcoal had the best effect on reducing the concentrations and effective concentrations of heavy metals in the sludge.
作者
王兴明
章珍
储昭霞
董鹏
梁淑英
邓瑞来
WANG Xingming;ZHANG Zhen;CHU Zhaoxia;DONG Peng;LIANG Shuying;DENG Ruilai(School of Earth and Environment,Anhui University of Science and Technology;Collaborative Innovation Center of Recovery and Reconstruction of Degraded Ecosystem in Wanjiang Basin Co-founded by Anhui Province and Ministry of Education,Anhui Normal University;Anhui Province Engineering Laboratory of Water and Soil Resources Comprehensive Utilization and Ecological Protection in High Groundwater Mining Area,Anhui University of Science and Technology;Key Laboratory of Bioresource and Environmental Biotechnology of Anhui Higher Education Institutes,School of Biological Engineering,Huainan Normal University;School of Metallurgy and Energy Engineering,Kunming University of Science and Technology;Chuzhou Municipal Ecology and Environment Bureau;Anhui Open Source Landscaping Engineering Co.,Ltd.)
出处
《环境工程技术学报》
CAS
CSCD
北大核心
2024年第2期528-537,共10页
Journal of Environmental Engineering Technology
基金
国家自然科学基金项目(51878004)
国家重点研发计划项目(2020YFC1908601,2019YFC1803501)
安徽省高校协同创新项目(GXXT-2020-075)
安徽省重点研究与开发计划项目(202104a06020027)
安徽省高校优秀人才重点支持计划项目(gxyqZD2021129)
安徽省高潜水位矿区水土资源综合利用与生态保护工程实验室开放课题项目(2022-WSREPMA-04)
安徽理工大学芜湖研究院研发专项(ALW2020YF08)
安徽开源园林绿化工程有限公司研发专项。
关键词
城市生活污泥
蚯蚓堆肥
玉米秸秆炭
重金属
urban domestic sludge
earthworm compost
corn straw charcoal
heavy metal
