天津市铬渣处理及利用途径

国外铬渣主要是经无害化处理后堆存、填海和垫地.我国对铬渣的处理仍以贮存为主.全国铬盐厂排出铬渣量约10万t/a堆存量达100万t,在铬渣综合利用技术方面我国在国际上占有领先地位.天津同生化工厂应主要考虑工艺的改进和废渣的综合利用.     

离子色谱法测定水溶性铬（Ⅵ）

自然界中的铬主要以铬(Ⅲ)和铬(Ⅵ)的形式存在.铬(Ⅲ)在生物体中少量存在,用以维持新陈代谢.铬(Ⅵ)在工业生产中具有极其广泛的应用,但是对环境造成了严重的污染,特别是对人体本身危害极大.美国Dionex(戴安)公司采用双官能基的 CS5分离柱可以同时检测铬(Ⅲ)和铬(Ⅵ),但灵敏度不是很高.鉴于铬(Ⅵ)的毒性,作为环境治理的主要目标,应该针对其特性进一步提高检测灵敏度和抗基体干扰的能力.     

城市污染河流沉积物中铬的形态与释放

本文着重探讨河流沉积物中铬的化学形态与溶出规律。用静态模拟与动态模拟实验研究了武昌巡司河底泥中铬的释放主要影响因素,测得其释放速率为5.44mg/m~2·d,即使污染河段中铬的几何均值高达344.4mg/kg,在正常水体条件下尚未构成二次污染威胁。     

酵母融合菌对铬离子的吸附特性研究

酵母融合菌的完整细胞、细胞壁、细胞内含物富集水体中的铬,比较了各组分对铬离子的吸附能力差异,并进行了模型拟合.结果表明:细胞壁的去除率和吸附量都明显高于完整细胞;完整细胞及细胞壁对铬的吸附均符合Freundlich和Langmuir热力学方程,且细胞壁对Cr6 的最大吸附量和吸附亲和力都大于完整细胞,说明细胞壁是该吸附剂吸附重金属离子的主要部位.同时利用多种分析手段研究了各组分对铬的吸附行为:酵母细胞壁的特殊结构以及AFM图显示细胞壁可以为活性基团吸附、络合或螯合金属离子提供更为广阔的空间;X-射线衍射和FTIR分析检测表明吸附剂对铬的吸附并未破坏其本身的结构.     

生物吸附处理含Cr废水的研究进展

综述了生物吸附法处理含铬废水的现状、生物吸附的机理以及各因素对吸附效率的影响,得出了微生物对废水中铬的良好去除效率.目前的研究集中于考察各因素对吸附效率的影响,并取得了一定的进展,但对吸附机理的研究不透彻,对多组分离子共存时的吸附过程和工程化应用研究的欠缺,是阻碍生物吸附剂发展的主要因素.     

Laboratory scale studies on removal of chromium from industrial wastes

Chromium being one of the major toxic pollutants is discharged from electroplating and chrome tanning processes and is also found in the effluents of dyes,paint pigments,manufacturing units etc.Chromium exists in aqueous systems in both trivalent(Cr^3 )and hexavalent (Cr^6 )forms.The hexavalent form is carcinogenic and toxic to aquatic life,whereas Cr^3 is however comparatively less toxic.This study was undertaken to investigate the total chromium removal from industial effluents by chemical means in order to achieve the Pakistan NEQS level of 1 mg/L by the methods of reduction and precipitation.The study was conducted in four phase Ⅰ,the optimum pH and cost effective reducing agent among the four popular commercial chemicals was selected.As a result,pH of 2 was found to be most suitable and sodium meta bisulfate was found to be the most cost effective reducing agent respectively.Phase Ⅱ showed that lower dose of sodium meta hisulfate was sufficient to obtain 100% efficiency in reducing Cr^6 to Cr^3 ,and it was noted that reaction time had no significance in the whole process.A design curve for reduction process was established which can act as a tool for treatment of industrial effluents.Phase Ⅲ studies indicated the best pH was 8.5 for precipitation of Cr^3 to chromium hydroxide by using lime.An efficiency of 100% was achievable and a settling time of 30 minutes produced clear effluent.Finally in Phase Ⅳ actual waste samples from chrome tanning and electroplating industries,when precipitated at pH of 12 gave 100% efficiency at a settling time of 30 minutes and confirmed that chemical means of reduction and precipitation is a feasible and viable solution for treating chromium wastes from industries.     

对工业含铬废水、铬渣处理的新方法和综合利用的新思路

本文以可靠的数据和化学原理,针对工业铬渣和含铬废水的实际情况提出处理的新方法和新思路,并应用于实践.     

硫酸亚铁还原法除地下水中六价铬

研究了受铬污染地下水的治理方法和技术，发现地下水中六价铬在中性条件下很容易用亚铁除去，Ｆｅ（Ⅱ）／Ｃｒ（Ⅵ）（摩尔比）为３，六价铬去率达１００％，反应速度快，可数分钟内完成，Ｆｅ（Ⅱ）还原Ｃｒ（Ⅵ）可采用接触过滤，不需反应池，投资少，运行费用低。