摘要
以燃煤电厂脱硫石膏为研究对象,对脱硫石膏中的主要成分和重金属进行分析,主要成分为硫酸钙,占比超过样品整体量的 90%,且主要存在形式为二水硫酸钙,其余主要杂质为SiO2、Al2O3、MgO,占比分别为2.93%,1.94%,0.77%.同时脱硫石膏中含有一定量的重金属,主要有Cu、Zn、Cr、Pb、Ba、Ni、As、Mn、Cd,含量分别为 3.12,47.22,18.76,2.14,0.14,7.12,1.23,31.41,0.37 mg/kg.同时采用硫酸硝酸浸出方法考察脱硫石膏重金属浸出毒性,发现该脱硫石膏中重金属浸出量不超标,但仍有一定的浸出量,对环境和后续资源化利用有着一定的影响.
Abstract
Taking desulfurization gypsum from coal-fired power plants as the research object,the main components and heavy metals in desulfurization gypsum were analyzed.The main component was calcium sulfate,accounting for more than 90%of the total sample amount,and the main form of existence was calcium sulfate dihydrate.The other main impurities were SiO2,Al2O3,and MgO,accounting for 2.93%,1.94%,and 0.77%,respectively.Meanwhile,desulfurization gypsum contains a certain amount of heavy metals,mainly Cu,Zn,Cr,Pb,Ba,Ni,As,Mn,and Cd,with contents of 3.12,47.22,18.76,2.14,0.14,7.12,1.23,31.41,0.37 mg/kg,respectively.At the same time,the sulfuric acid nitric acid leaching method was used to investigate the toxicity of heavy metal leaching in desulfurization gypsum.It was found that the heavy metal leaching amount in the desulfurization gypsum did not exceed the standard,but there was still a certain amount of leaching,which had a certain impact on the environment and subsequent resource utilization.