电渗析在含氰金矿废水资源化处理中的应用研究

发布时间：2018-01-30 10:07

本文关键词： 电渗析(ED) 单价阴离子交换膜氰化物铜金矿废水膜污染　出处：《中国海洋大学》2015年硕士论文　论文类型：学位论文

【摘要】：自1887年MacArthur实现氰化提金的商业化应用以来,由于氰化物浸金工艺稳定成熟,氰化法作为黄金提取的主要方法沿用至今。然而,在氰化法提取黄金的过程中,会产生含有氰化物和重金属铜的金矿废水。许多国家和地区的环境保护部门都设定了严格的含氰废水排放标准,去除(或者回收)金矿废水中的氰化物和重金属铜等有毒物质势在必行。但目前的一些方法或由于试剂消耗高、或由于技术壁垒、或由于操作步骤复杂、或由于对设备有特殊要求等原因而难以简单高效地处理含氰金矿废水中的氰化物和重金属铜。因此,开发一种去除效率高、试剂消耗少、无二次污染排放的方法势在必行。在苦咸水淡化、锅炉补给水生产、食物产品去矿化、食盐生产、电镀废水处理等方面的工业应用中,电渗析(Electrodialysis，ED)已经被证明是一种有效、环保的技术。然而，在利用电渗析技术处理金矿废水方面的研究较少,而且处理过程中的离子交换膜污染问题还没有被报道。另外,传统的三隔室电渗析虽然可以去除废水中的氰化物,但浓室出水中更高浓度的有毒物质依然难以处理。因此传统的电渗析方法并不能够有效实现废水中氰化物的资源化,新的电渗析技术还有待开发。本文针对以上问题,以山东省招远市黄金冶炼厂的金矿废水为处理对象,考察电渗析技术处理含氰金矿废水的可行性。具体内容及结论如下：利用有效面积为88 Cm2的三隔室电渗析分别对模拟和实际含氰金矿废水中的氰化物和重金属铜进行去除。通过FTIR、SEM-EDX、膜电阻和静态接触表测量等方法对运行前后的离子交换膜污染问题进行了分析探究。研究了操作电压、初始浓度和操作流量对铜和氰化物的去除率的影响。结果表明：最佳操作条件分别为操作电压25V,初始浓度C2(其中氰化物和铜的含量分别为242 mg/L和47mg/L),流量4.17 mL/s氰化物和铜的最佳的去除率分别为99.83%和99.41%。经过处理后的实际金矿废水中氰化物(0.48 mg/L)和铜(0.44 mg/L)、锌(0.34 mg/L)等重金属的含量都可以达到国家的排放标准(铜0.5 mg/L,氰化物0.5 mg/L,锌2.0 mg/L)。膜污染物中存在CuCN, [Cu(CN)3]2-，，Cu(OH)2和Zn(OH)2等物质；而且通过合理调节溶液的pH可以明显减轻阴离子交换膜的膜污染情况。提出了新型五隔室电渗析对含氰金矿废水进行处理。共设计了两个实验模式,在模式1中,分别利用均相离子交换膜和异相离子交换膜对金矿废水中的氰化物进行去除处理：在模式2中,利用均相单价阴离子交换膜(1-AEMs)和均相阳离子交换膜(CEMs)对废水中的氰化物进行回收。对其中的重要工艺参数(操作压力)进行优化以提高氰化物的去除和回收效率。另外,还初步探究了处理过程中的pH变化。结果表明：在模式2中,CN-的提取率最高可达到87.14%,此时的操作电压为30 V,能耗为8.33 kWhm-3。在模式1中,当采用均相离子交换膜时,氰化物的去除率最高可达到97.90%,此时的操作电压为38V,远高于使用异相离子交换膜的74.02%。与此同时,在设备运行过程中,两种模式都能实现碱溶液的回收,并能将其回用于电渗析过程的pH调节中。该研究在工业应用方面对氰化物的资源回收提供了新思路。
[Abstract]:Since the commercial application of cyaniding since 1887 to achieve MacArthur, the gold leaching process is stable and mature, as the main method of cyanidation gold extraction used today. However, in the extraction of gold cyanidation process, will produce gold mine wastewater containing cyanide and heavy metal copper. Many countries and regions have set up environmental protection department the cyanide wastewater discharge standard with strict, remove (or recovery) of copper cyanide and heavy metals and other toxic substances in wastewater is imperative. But some current methods or due to high reagent consumption, or due to technical barriers, or because of the complicated operation steps, or because of the special requirements of the reason to simple and efficient processing equipment cyanide containing wastewater of cyanide and heavy metals. Therefore, the development of a high removal efficiency, less reagent consumption, no two pollution emissions is imperative. In the desalination of brackish water, boiler water supply production, food products to mineralization, salt production, industrial application of electroplating wastewater treatment in the electrodialysis (Electrodialysis, ED) has been proved to be an effective and environmentally friendly technologies. However, less research in the use of dialysis treatment and the electric wastewater, treatment in the process of ion exchange membrane pollution problem has not been reported. In addition, the traditional three compartment electrodialysis can be the removal of cyanide, but the concentrated chamber has a higher concentration of toxic substances in the water is still difficult to deal with. So the traditional electrodialysis method can not effectively realize resoureilization of cyanide in wastewater, electrodialysis the new technology has yet to be developed. In order to solve this problem, Shandong city of Zhaoyuan Province in the wastewater gold smelter as treatment object, investigation of electrodialysis treatment of cyanide containing wastewater is feasible. The specific contents and conclusions are as follows: using the effective area of 88 Cm2 three compartment electrodialysis were simulated and actual wastewater containing cyanide in cyanide and heavy metal removal. By FTIR, SEM-EDX, ion membrane resistance and static contact measurement method of operation before and after the exchange membrane pollution problems are analyzed research of the operating voltage, initial concentration and operation flow of copper and cyanide removal rate were investigated. The results show that the optimum operating conditions were operating voltage of 25V, the initial concentration of C2 (the content of cyanide and copper were 242 mg/L and 4.17 mL/s 47mg/L), the flow of cyanide and copper removal rates were the best 99.83% and 99.41%. after the actual gold cyanide in the waste water after treatment (0.48 mg/L) and copper (0.44 mg/L), zinc (0.34 mg/L) content of heavy metals can reach the national emission standards (Cu 0.5 mg/L, Cyanide is 0.5 mg/L, 2 mg/L). The presence of CuCN zinc pollutants, [Cu (CN) 3]2-, Cu (OH) 2 and Zn (OH) 2 and other substances; membrane fouling can significantly reduce the anion exchange membrane by adjusting the pH of the solution was put forward. The new five compartment electrodialysis for cyanide gold mine wastewater treatment. A total of two experiments were designed, in model 1, respectively by using homogeneous ion exchange membrane and heterogeneous ion exchange membrane of gold cyanide removal in wastewater treatment: in mode 2, using homogeneous monovalent anion exchange membrane (1-AEMs) and homogeneous cation exchange membrane (CEMs) the recovery of cyanide in Wastewater. The important parameters of the (operating pressure) is optimized to improve the removal efficiency and recovery of cyanide. In addition, preliminary explored the pH changes during the treatment process. The results showed that: in mode 2, CN- extraction rate can reach 87 .14%, the operating voltage is 30 V, the energy consumption is 8.33 kWhm-3. in mode 1, when using the homogeneous ion exchange membrane, the cyanide removal rate reached 97.90%, the operating voltage is 38V, much higher than the use of heterogeneous ion exchange membrane of 74.02%. at the same time, the equipment operation process, two a model can realize the recovery of alkali solution, and can be used in the electrodialysis process in the regulation of pH. This study provides a new idea in the industrial application of cyanide recycling.

【学位授予单位】：中国海洋大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X753

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