摘要
通过柱淋溶实验,分别研究不同离子强度或不同流速作用下,生物炭在石英砂柱中的迁移特征及驱动机制.结果表明,淋溶结束时,在高离子强度条件下,生物炭从生物炭层向石英砂柱中迁移的总质量最大,与1号柱(CK)相比,迁移质量提高了62%;主要驱动力为界面化学作用,高离子强度抑制了生物炭内部碱性物质的释放,颗粒表面双电层被压缩,降低了ζ电位,更多生物炭颗粒滞留在不稳定的第二极小势能处,易迁移出炭层.在高流速条件下,生物炭在石英砂柱中径向迁移深度最大,最大迁移深度为3.5—4 cm.主要驱动力为水力学作用,流速的增加,产生的水动力剪切力促使生物炭大聚体分散成小聚体,有利于生物炭随水流向径向深处迁移.
The migration characteristics and driving mechanism of biochar in quartz sand column were studied through column leaching experiment under different ionic strength or flow rate.The experiment results showed that,at the last stage of the leaching process,the total mass of biochar migration from biochar layer to quartz sand column under the condition of high ion strength was the largest,which was 62%higher than that of column 1(CK).The main driving force was interface chemistry,and the high ionic strength inhibited the release of internal alkaline substances from the biochar.In addition,the particle surface electric double layer was compressed,and zeta potential was reduced,so more biochar particles were stranded in the instability of the minimum potential energy,making it easier to migrate out of the carbon layer.Under the condition of high flow rate,the maximum radial migration depth of biochar in quartz sand column was 3.5—4 cm,for which the main driving force was hydraulics.With the increase of the flow rate,the generated hydrodynamic shear force promoted the large polymer of biochar to disperse into small polymer,this made the migration of biochar to the radial depth along with the water flow easier.
作者
李星燃
高鹏
祝妍华
梁媛
LI Xingran;GAO Peng;ZHU Yanhua;LIANG Yuan(School of Environmental Science and Engineering,Suzhou University of Science and Technology,Suzhou,215009,China;Suzhou National Hi-Tech District Environmental Monitoring Brigade,Suzhou,215009,China)
出处
《环境化学》
CAS
CSCD
北大核心
2020年第5期1410-1419,共10页
Environmental Chemistry
基金
“十三五”国家水体污染控制与治理科技重大专项(2017ZX07205002)
国家自然科学基金(青年)(21507097)
江苏省自然科学基金(BK20150288)
苏州科技发展支撑(社会发展)计划(SS2019027)资助
关键词
生物炭
柱淋溶
迁移
界面化学
水力学
biochar
column leaching
migrate
interface chemistry
hydraulics
作者简介
通讯联系人:梁媛,E-mail:liangyuan@usts.edu.cn
