Heavy metal migration in soils and rocks at historical smelting sites

The vertical migration of metals through soils and rocks was investigated at five historical lead smelting sites ranging in age between 220 and 1900 years. Core samples were taken through metal-contaminated soils and the underlying strata. Concentration profiles of lead and zinc are presented from which values for the distances and rates of migration have been derived. Slag-rich soil horizons contain highly elevated metal concentrations and some contamination of underlying strata has occurred at all sites. However, the amounts of lead and zinc that have migrated from soils and been retained at greater depths are comparatively low. This low metal mobility in contaminated soils is partly attributed to the elevation of soil pH by the presence of calcium and carbonate originating from slag wastes and perhaps gangue minerals. Distances and rates of vertical migration were higher at those sites with soils underlain by sandstone than at those with soils underlain by clay. For sites with the same parent material, metal mobility appears to be increased at lower soil pH. The mean migration rates for lead and zinc reach maxima of 0.75 and 0.46 cm yr^–1 respectively in sandstone at Bole A where the elements have moved mean distances of 4.3 and 2.6 m respectively. There is some evidence that metal transport in the sandstone underlying Bole A and Cupola B occurs preferentially along rock fractures. The migration of lead and zinc is attenuated by subsurface clays leading to relatively low mean migration rates which range from 0.03 to 0.31 cm yr^–1 with many values typical of migration solely by diffusion. However, enhanced metal migration in clays at Cupola A suggest a preferential transport mechanism possibly in cracks or biopores.     

小黄磷生产企业磷矿渣的综合利用

某县化工厂小黄磷矿渣＾２２６Ｒａ比活度较高，＾２３２Ｔｈ及＾４０Ｋ比活度相对偏低。用于生产农用硅肥投资较小，不会造成放射性污染；用于生产磷渣硅酸水泥投资较大，但也不会造成放射性污染；用于生产废渣砖投资不大，利用率高，但有一定放射性污染风险。     

环保型高效胶结材——高炉渣微粉的制造与应用

本文介绍了高炉渣微粉的性质、特点、生产工艺及粉磨设备的选择和应用前景分析。     

从工业废料制取化学建材石膏的研究

研究了以造纸白泥、电石渣及工业废硫酸为原料化学建材石膏的原料二水石膏的工艺条件和影响因素，同时采用废水闭路循环回用工艺流程，防止二次污染的产生。实验表明，将废渣配成１０％浓度的浆液与低浓度废硫酸进行反应，控制一定的反应时间及终点ＰＨ值可制得含量达９０％以上的优质二水石膏。     

钢渣直接熔制高档陶瓷产品

钢渣是目前排放量较大的一种典型工业废渣 ,我国有效利用率仅 10 % ,对环境造成极大的危害。在此介绍一种利用排放热态钢渣直接熔制高档陶瓷产品的新技术 ,并对产品的显微结构和经济性进行了分析。结果表明 ,钢渣热态资源化技术是一项具有广阔应用前景的钢渣资源化技术     

硅锰渣理化性质的分析与表征

硅锰渣是冶炼硅锰合金时排放的一种工业废渣。文章借助于SEM/EDS、XRD等现代测试方法,对其理化性质进行分析和表征,结果表明:硅锰渣是由一些形状不规则的多孔非晶质颗粒组成,粒径主要集中在250μm以上,其化学成分主要是SiO2和CaO,其次是Al2O3、MnO。硅锰渣中微量元素未超过排放标准、放射性符合装修材料的技术要求。硅锰渣经高温煅烧后,生成一些新的晶相。     

矿渣对废水中铅,铬的吸附去除试验

进行了矿渣去除废水中铬、铅离子的试验研究，探讨了接触时间、金属离子初始浓度、废水酸度等因素对吸附性能的影响。结果表明，有较宽的ｐＨ范围内矿渣对铬、铅离子有较强的吸附能力，基本符合Ｆｒｅｕｎｄｌｉｃｈ吸附等温式，铅离子的吸附容量略大于价铬离子。     

铁屑微电解法处理农药废水的研究

铁屑微电解法能有效去除农药 (三唑磷、田安、杀虫双和单杀虫 )生产废水中的CODCr、色度、As、氨氮、有机磷和总磷。去除率分别可达 76 .2 %、80 %、6 9.2 %、5 5 .7%、82 .7%和 6 2 .8% ;与铁盐混凝法相比 ,微电解法能更有效地去除污染物 ,提高废水的可生化性     

液态高炉渣热量回收利用方法及问题

钢铁冶金行业生产会产生大量的高炉渣。高炉渣由于自身温度比较高，含热量丰富，对能源工业来说是一种很好的二次资源。世界上已有一些国家对高炉渣热量的回收利用进行了一定的研究，而国内这方面的研究却很少。详细介绍了近几年国内外对高炉渣热量回收利用的情况，在此基础上，阐述了高炉渣热回收技术需要解决的关键问题和发展趋势。     

液态高炉渣热量回收利用方法及问题

钢铁冶金行业生产会产生大量的高炉渣.高炉渣由于自身温度比较高,含热量丰富,对能源工业来说是一种很好的二次资源.世界上已有一些国家对高炉渣热量的回收利用进行了一定的研究,而国内这方面的研究却很少.详细介绍了近几年国内外对高炉渣热量回收利用的情况,在此基础上,阐述了高炉渣热回收技术需要解决的关键问题和发展趋势.