在金矿开采中作为Merrill-Crowe工艺副产品产生并从含汞废物中回收的废液汞必须稳定,以便安全储存或处置。这项研究开发了一种稳定汞的程序。使用容量为0.5m3且转速为43rpm的球磨机来用硫稳定残留的汞。以1.0、0.8和0.67的汞:硫摩尔比进行处理30、60和90分钟。球加载比为7.0,有残留汞,温度低于40℃。通过使用毒性特征浸出程序(TCLP)测量汞和其他金属的浓度来评估处理效率。通过X射线衍射检查稳定的残留汞,并对大型水蚤和苜蓿进行生物测定。对上述变量进行主成分分析(PCA)。90分钟的治疗,与其他处理相比,汞与硫的摩尔比为0.67,主要以朱砂的形式稳定汞,渗滤液汞值低于检测限<0.003。来自处理的渗滤液也显示出21.28-38.44毒性单位的值,归类为剧毒,并产生毒性,特别是对于麦格纳博士来说,由于铝等其他金属的存在,Ba,B,Ca,Cu,Cr,Fe,Mn,Ni,和Zn。PCA分析中残留物的可变性可以通过处理效果和残留汞中其他金属的存在来解释。获得的稳定的残留汞被归类为非危险物质,可以作为普通废物储存或处置在安全垃圾填埋场。
Waste liquid mercury generated as a by-product of the Merrill-Crowe process in gold mining and recovered from mercury-containing waste must be stabilized for secure storage or disposal. This study developed a procedure for mercury stabilization. A ball mill with a 0.5 m3 capacity and a rotational speed of 43 rpm was used to stabilize the residual mercury with sulfur. The treatments were conducted for 30, 60, and 90 min at mercury: sulfur molar ratios of 1.0, 0.8, and 0.67. The ball loading ratio was 7.0 with residual mercury, and the temperature was below 40 °C. The treatment efficiency was evaluated by measuring the concentrations of mercury and other metals using the Toxicity Characteristic Leaching Procedure (TCLP), examining the stabilized residual mercury by X-ray diffraction, and conducting
bioassays on Daphnia magna and Lactuca sativa. Principal component analysis (PCA) was performed on the aforementioned variables. The 90-min treatment, with a mercury-to-sulfur molar ratio of 0.67, stabilized mercury mainly as cinnabar compared with the other treatments and presented leachate mercury values below the detection limit <0.003. The leachate from the treatments also showed values of 21.28-38.44 toxic units, classified as very toxic, and generated toxicity, particularly for D. magna, because of the presence of other metals such as Al, Ba, B, Ca, Cu, Cr, Fe, Mn, Ni, and Zn. The variability of the residues in the PCA analysis was explained by the treatment effect and the presence of other metals in the residual mercury. The stabilized residual mercury obtained was classified as non-hazardous and could be stored or disposed of as ordinary waste in a security landfill.