铸造废砂的环境毒性研究  

Environmental Toxicity of Waste Foundry Sand

作　　者：张海凤[1] 王玉珏[1,2] 王劲璘[3] 黄天佑[4] 熊鹰 

机构地区：[1]清华大学环境学院,北京100084 [2]清华大学环境模拟与污染控制国家重点联合实验室,北京100084 [3]昆明理工大学管理与经济学院,昆明650093 [4]清华大学机械系,北京100084 [5]重庆长江造型材料(集团)有限公司,重庆400700

出　　处：《环境科学》2013年第3期1174-1180,共7页Environmental Science

基　　金：国家自然科学基金项目(51008175);国家高技术研究发展计划(863)项目(2009AA06A417-08)

摘　　要：采用毒性特性浸出程序、顶空气相色谱技术检测了5种铸造废砂中的重金属与有机污染物,采用发光细菌毒性检测技术和土壤酶活性实验研究了废砂的生物效应.结果表明,由于浇注金属与造型材料的不同,5种铸造废砂中的金属与有机污染物成分和浓度均有较大差异.其中,铸铁与铸钢废砂浸出液中的铁离子,铸铝废砂中的As离子超出了《地表水环境标准》规定的最大允许检出浓度.5种废砂中的有机污染物种类十分复杂,对发光细菌表现出不同程度的抑菌活性,发光强度的抑制率在30%～95%之间.此外,土壤酶活性实验结果表明,废砂中的金属污染物可能会抑制土壤中微生物的活性,而有机物则对土壤微生物的活性有一定的促进作用.因此,铸造废砂的随意排放将会对环境造成较严重的威胁.The metal leaching characteristics and volatile organic compounds （VOCs） of five different types of waste foundry sands were analyzed with the toxicity characteristic leaching procedure （TCLP） and head space-gas chromatography （HS-GC）. MicrotoxTM and soil dehydrogenase activity （DHA） tests were then used to evaluate the bio-effects of these waste sands. The results showed that due to the different metals poured and casting materials used to make the sand molds, there was significant difference among the five waste foundry sands in the compositions and concentrations of metal and organic pollutants. The concentrations of Fe in the leachates of iron and steel casting waste foundry sand exceeded the maximal allowable concentrations specified in the National Standard of Drinking Water Quality, whereas the As concentration in the leachate of aluminum casting waste foundry sand exceeded the standard. The five waste foundry sands had quite different compositions and levels of VOCs, which resulted in different levels of inhibition effects on the luminescent bacteria （30% and 95% ）. Additionally, the soil DHA tests suggested that metal pollutants in waste foundry sands may inhibit the soil microbial activity, whereas organics in the sands may slightly promote the microbial activity. The results of this study indicated that the waste foundry sands may pose considerable threat to the environment when improperly disposed.

关 键 词：铸造废砂 毒性特性浸出程序 挥发性有机物 发光细菌 重金属 

分 类 号：X171.5[环境科学与工程—环境科学]