【摘要】 用氨水和硫酸铵浸出废水处理渣中的钴铜,考察了浸出时间、反应温度、液固比、硝酸铵加入量和氨水浓度对钴铜浸出率的影响。结果表明,含钴铜废水处理渣的最佳浸出条件为:浸出时间5 h,浸出温度50℃,氨水浓度3 mol/L,硫酸铵浓度1 mol/L,液固比8∶1。在此条件下钴和铜的浸出率分别为70%~80%和60%~70%。更多还原

【Abstract】 This paper is aimed at investigating the leaching behaviors of cobalt and copper from the sewage treatment sludge by using ammonium salts systematically. For the above purposes,we have combined the study of sewage with the slag added by a certain amount of ammonium sulfate,in hoping to find the effects of leaching time,the reaction temperature,the liquid-to-solid ratio,addicting of ammonium nitrate and ammonium sulfate concentration on the leaching rate of cobalt and copper,respectively. The results gained from our experiment and investigation show that their leaching rate can be made improved with the prolonging of leaching time,reaching its maximum limit with the premium leaching time increased to 5 h. Based on the theory of leaching kinetics,proper leaching temperature can be regulated to the range from 50 ℃ to 70 ℃ in benefit of the leaching process. The most appropriate ratio for the leaching process tends to be that of 8: 1. What is more,we have also found that the presence of ammonium nitrate proves to be helpful to enhance the leaching ratio both of cobalt and copper,with the maximum value attained by adding 2 g NH4NO3to the process. At the same time,the ammonium concentration can also be found having noticeable influence on the said leaching rate,which implies that the leaching rate tends to be promoted by increasing the ammonium concentration. For example, when the concentration was set at 3 mol / L,the said leaching rate could be expected to reach 80. 33% and 68. 99%. The results also indicate that the optimum leaching conditions for such sewage treatment sludge containing cobalt-copper can be laid out as follows: the leaching time: 5 h; the reaction temperature: 50 ℃; the concentration of ammonia and ammonium sulfate 3. 0 mol / L and 1. 0 mol / L, and,the liquid-to-solid ratio 8: 1. Under such conditions,the leaching rate of cobalt and copper can be expected to reach 70%-80% and 60%-70%,respectively.更多还原