电解锰渣的水泥固化与浸出毒性研究  

On the solidification of electrolytic manganese residue with cement and its leaching toxicity

作　　者：方选进[1] 王智[1] 钱觉时[2] 蒋小花[2] 侯鹏坤[2] 

机构地区：[1]重庆大学化学化工学院,重庆400044 [2]重庆大学材料科学与工程学院,重庆400045

出　　处：《安全与环境学报》2010年第5期46-49,共4页Journal of Safety and Environment

基　　金：国家863项目(2008AA031206)

摘　　要：针对电解锰渣产量大且渣中水溶性锰严重超标的问题,采用水泥作为固化剂对电解锰渣进行处理,研究了水泥掺量对破碎固化体(颗粒粒径d<5 mm)浸出毒性的影响,模拟了酸雨对固化体表面浸出率和破碎固化体浸出毒性的影响,并采用XRD分析了电解锰渣固化前后的矿物组成。结果表明,水泥质量分数为15%～45%的破碎固化体中锰的浸出质量浓度低于国家标准(2 mg/L);水泥质量分数为45%的固化体在pH>3.0的酸雨中的早期表面浸出率数量级仅为10^(-5)g(cm^2·d),后期则检测不到;水泥质量分数为25%～45%的破碎固化体在pH=1.0的酸性环境中的锰浸出浓度均不超标。电解锰渣水泥固化前后的矿物组成结果显示,电解锰渣水泥固化后的锰浸出率减小是由于其中的水溶性锰被水泥水化产物包容吸附,且固化后水溶性Mn^(2+)转化为不溶、低毒性的MnO_2也有利于消除锰对环境的危害。Electrolytic manganese residue （EMR） is a kind of harm- ful solid waste existing in great amounts in the manganese refining in- dustry, which comes from the production of manganese when its ore is used to produce the electrolytic manganese powder, particularly when the water-soluble manganese in EMR has greatly exceeded the limit. The solidification of EMR with cement was experimentally studied and the relation between the cement content and leaching toxicity of the broken solidified body （particle size d 〈 5 mm） was revealed so as to find their superficial leaching rate R and their leaching toxicity of broken solidified body under the acidic condition. Then the crys- talline phases of EMR before and after solidification were analyzed by means of X-ray Diffraction （XRD） spectra. The results of the experi- ments show that Mn mass concentration in the broken solidified body leaching was smaller than that in the national standard （2 mg/L） with the cement mass fraction being 15% - 45% of the mixture. When the mass fraction of cement was up to 45 %, the R of the solidified broken body would be of the order of 10 5 g. cm- 2. d- 1 in the acidic condition （pH 〉 3.0） in the early age, and the R can not be detect- ed in the old age. The result also indicated that the leaching concen- tration of Mn did not exceed the limit when the broken solidified body （with the cement mass fraction of 25 % - 45 % ） was detected in acid condition （pH = 1.0）. The crystalline phase analysis of EMR before and after stabilization shows that tile cause of R getting lower after solidification is the stabilization and adsorption of Mn2＋ by the cement hydrates. Besides, the conversion of water-soluble Mn2＋ into insolu- ble and lower toxic MnO2 can also contribute to the elimination of its pollution to the environment. Thus, it can be seen that the above in- vestigation and analysis help to lay a trustful foundation for pollution prevention and rational disposal for EMR.

关 键 词：环境工程学 电解锰渣 水泥固化 浸出毒性 表面浸出率 

分 类 号：X506[环境科学与工程—环境工程]