MgCl_(2)和脱水矿泥对赤泥盐碱性的调控  

Conditioning of salinity and alkalinity in red mud by MgCl_(2) and dehydrated mineral slime

作　　者：张宇玲 成官文[1] 韦桥权 徐晓宇 岳远隋 徐敏 冯杰 农国武[2] ZHANG Yuling;CHENG Guanwen;WEI Qiaoquan;XU Xiaoyu;YUE Yuansui;XU Min;FENG Jie;NONG Guowu(College of Environmental Science and Engineering,Guilin University of Technology,Guilin 541006,China;Guangxi Branch of Aluminum Corporation of China Limited,Baise 531499,China)

机构地区：[1]桂林理工大学环境科学与工程学院,桂林541006 [2]中国铝业股份有限公司广西分公司,百色531499

出　　处：《环境工程学报》2022年第3期937-945,共9页Chinese Journal of Environmental Engineering

基　　金：中国铝业股份有限公司科技攻关项目(gxzz201903);广西重点研发计划(桂科AB20297039)。

摘　　要：针对赤泥盐碱性过高造成资源化利用难的问题,采用MgCl_(2)和氧化铝工业固体废物脱水矿泥对赤泥进行盐碱性调控,并依据赤泥的pH、电导率、碱性阴离子(OH^(-)、CO_(3)^(2-)、HCO3-、AlO_(2)^(-))和可溶性盐分阳离子(K^(+)、Ca^(2+)、Na^(+)、Mg^(2+))质量分数以及黑麦草种子发芽率结果表征盐碱性调控效果。结果表明,当赤泥投加7‰MgCl_(2),并与脱水矿泥按1∶4质量比混合处置时,其pH从11.36降至8.43,电导率从1.557mS·cm^(-1)降至1.166 mS·cm^(-1),黑麦草种子发芽率达到99.67%。赤泥pH、电导率以及OH^(-)、CO_(3)^(2-)、AlO_(2)^(-)、K^(+)、Ca^(2+)、Na^(+)、Mg^(2+)质量分数随着MgCl_(2)投加量和脱水矿泥混合比例的增加而降低,黑麦草种子发芽率因此而随之增加,显示了良好的盐碱性调控效果。本研究结果可为氧化铝工业固废赤泥盐碱性调控提供参考。In order to solve the problem of difficulty in resource utilization caused by excessive salinity and alkalinity of red mud,MgCl_(2)and dehydrated mineral slime of alumina industrial solid waste were used to control salinity and alkalinity of red mud.The effect of salinity and alkalinity regulation of red mud was characterized by pH,conductivity,mass fraction of alkaline anions(OH^(-),CO_(3)^(2-),HCO3-,AlO_(2)^(-)),mass fraction of soluble salt cations(K^(+),Ca^(2+),Na^(+),Mg^(2+))and germination rate of ryegrass seeds.The results showed that when red mud added with 7‰MgCl_(2)and mixed with dehydrated mineral slime at a mass ratio of 1∶4,pH decreased from 11.36 to 8.43,conductivity decreased from 1.557 mS·cm^(-1) to 1.166 mS·cm^(-1),and germination rate of ryegrass seeds reached 99.67%.The pH,conductivity and mass fractions of OH^(-),CO_(3)^(2-),AlO_(2)^(-),K^(+),Ca^(2+),Na^(+)and Mg^(2+)of red mud decreased with increase of MgCl_(2)addition and mixture ratio of dehydrated mineral slime,thus germination rate of ryegrass seeds increased,which showed a good effect on salinity and alkalinity regulation.The results of this study can provide the basis for control salinity and alkalinity of solid waste red mud in alumina industrial.

关 键 词：赤泥 MgCl_(2) 脱水矿泥 盐碱性调控 种子发芽率 

分 类 号：X705[环境科学与工程—环境工程]