卧式球磨机处理高浓度HCHs污染土壤工艺参数优化

为了对自主研发的卧式机械化学球磨设备的工艺参数进行优化，为设备的完善、放大及应用积累基础数据，以某有机氯农药污染地块高浓度六六六(HCHs)污染土壤为供试土壤，利用普通生石灰作为球磨药剂进行机械化学脱卤，以不同球磨时间土壤中HCHs的去除率为指标，通过正交试验对球料比和物料比两个影响球磨效果的重要参数进行优化. 结果表明:①卧式机械化学球磨设备处理HCHs的最佳工艺参数组合为球料比10∶1、物料比1∶2，且物料比1∶5和1∶2两种水平对去除率的影响无显著差异，因此实际应用时物料比可选择1∶5，以减少药剂添加量. 验证试验得出，在球料比10∶1、物料比1∶5的工艺参数组合下，0.5 h的HCHs去除率平均值为91.1%，1.0 h时为96.04%，表明优选的工艺参数组合稳定可行. ②球磨0.5 h后，正交试验的各组处理中HCHs的去除率为65.21%~99.94%，1.0 h后为72.44%~99.98%，证实自主研发的球磨机能有效处理污染土壤中的HCHs. 研究显示，卧式球磨设备可高效处理HCHs污染场地土壤，并且具有操作简单、处理流程短等优势，具有较大的应用潜力，可进一步放大设备体积，优选的工艺参数可进行实际应用. 

Optimization of Operating Parameters for Treatment of Hexachlorocyclohexane (HCH) Heavily Contaminated Soil by Horizontal Ball Mill

In order to optimize the operating parameters of an independently developed horizontal ball mill and to provide basic data for the improvement, scale-up, and application of the equipment, we conducted a quicklime-based mechanochemical destruction (MCD) study using HCHs heavily contaminated soil from an organochlorine pesticide factory. Taking the removal rate of HCHs over time as an index, charge ratio and material ratio, the two important parameters controlling the performance of MCD treatment were optimized by orthogonal experiments. The results showed: (1) Charge ratio of 10∶1 and material ratio of 1∶2 were the optimal operating parameters for the treatment of HCHs in the plant. Because there was no significant difference in the effect of two levels of the material ratio of 1∶5 and 1∶2 on the removal rate, the charge ratio of 10∶1 and material ratio of 1∶5 were selected as the optimal operating parameters for the sake of cost and other practical considerations. Under the conditions of charge ratio of 10∶1 and material ratio of 1∶5, the average HCHs removal rate reached 91.1% in 0.5 h and 96.04% in 1.0 h, indicating that the optimized parameters were viable. (2) HCHs removal rates reached 65.21%-99.94% and 72.44%-99.98% in 0.5 h and 1.0 h, respectively. It confirms that the horizontal ball mill is able to treat HCHs in contaminated soil efficiently. The horizontal ball mill presented in this study has great potential for scaling up and application in MCD treatment of HCHs contaminated soil. The optimized process parameters may be applied in practice.