Solubility of ion and trace metals from stabilized sewage sludge by fly ash and alkaline mine tailing

Stabilized sewage sludge （SS） by fly ash （FA） and alkaline mine tailing as artificial soil, to be applied on the ecological rehabilitation at mining junkyards, offers a potentially viable utilization of the industrial by-product, as well as solves the shortage of soil resource in the mine area. An incubation experiment with different ratios of SS and FA was conducted to evaluate the solubility of ions and trace elements from stabilized sewage sludge. Results showed that fly ash offset a decrease in pH value of sewage sludge. The pH of （C） treatment （FA：SS = 1：1） was stable and tended to neutrality. The SO4^2- and Cl^- concentrations of the solution in the mixture were significantly decreased in the stabilized sewage sludge by alkaline fly ash and mine tailing, compared to the single SS treatment. Stabilized sewage sludge by FA weakened the nitrification of total nitrogen from SS when the proportion of FA in the mixture was more than 50%. The Cr, Ni, and Cu concentrations in the solution were gradually decreased and achieved a stable level after 22 days, for all treatments over the duration of the incubation. Moreover stabilized sewage sludge by fly ash and/or mine tailing notably decreased the trace metal solubility. The final Cr, Cu, and Ni concentrations in the solution for all mixtures of treatments were lower than 2.5, 15, and 50 μg/L, respectively.     

铬渣钡渣代替天然砂制作混凝土的研究

用铬渣、钡渣代替部分天然砂制作强度等级为C15的普通混凝土,混凝土的强度等级与钡渣、铬渣的加入量关系较大.用PO32.5标号水泥,铬、钡渣的质量代替砂子质量的50%时,混凝土的抗压强度达到18.9MPa,比普通混凝土设计的抗压强度提高26%,混凝土的收缩量为1/300,优于国家标准,对混凝土作浸出毒性试验,Cr6+和Ba2+都远小于国家规定的标准值.     

细菌解毒铬渣及其选择性回收铬的新技术通过鉴定

2005年9月19日，中南大学与湖南正元环保科技有限公司共同推出的“细菌解毒铬渣及其选择性回收铬的新技术”获得了中国工程院院士张杰为首的专家鉴定委员会的一致通过，并获得“填补了空白、居国际领先水平”的高度评价。     

硫铁矿烧渣综合利用研究进展

通过对硫铁矿制硫酸产生的烧渣，用于建筑材料，化工产品，净水剂等方面的综合利用研究进展情况进行了论述，对综合回收金，银等矿物资源研究状况进行了讨论，并介绍了应用实例。     

熔融还原解毒后铬渣的稳定性研究

着重阐明了铬渣经旋风炉附烧有炉外水淬处理后生成的玻璃体粒化解毒性的安定性问题，通过对解毒渣的物相结构，浸溶性和高温稳定性等试验分析，最终判明解毒渣在小于或等于５００℃条件下没有反玻璃化倾向，在自然环境中储放和用作建材，都是安定和安全的。     

硫铁矿烧渣制备硫酸亚铁及效益估算

本文将硫铁矿烧渣熟化处理后得到酸性硫铁铁溶液。正交实验说明影响铁回收率的熟化因素强弱依次为硫酸浓度〉熟化时间〉熟化温度〉硫酸用量，最佳条件下，铁回收率可达９０％，利用废铁还原上述有够制备得到含ＦｅＳＯ４．７Ｈ２Ｏ９８％以上的产品，用这种方法充酸亚铁具产品质量好、环境效益和经济效益佳。