The Study On The Recycle Treatment Of Electroplating Sludge In Chongqing Fenghuang Electroplating Industrial Park

Electroplating plays an important role on industrial production. However, attentions are paid to the three kinds of pollutants of the electroplating process for electroplating waste water, plating waste gas and electroplating sludge, which pollute the environment seriously. Heavy metals could transfer from electroplating waste water to the electroplating sludge, thus, the harm is lager in electroplating sludge than in waste water. Fenghuang Electroplating Industrial Park, which is belonged to Chongqing Apollo Company,is plating processing zones. There are several serious problems in industrial parks such as waste, resources and energy consumption, and electroplating sludge treatment is not effective. Therefore, it is practical significance to solve electroplating sludge treatment problem in Industrial Park.In this dissertation, the importance of the study of electroplating sludge's recovery is introduced. The development of electroplating sludge treatment and its recovery were overviewed. The property and treatment process of electroplating sludge were studied by field surveys and sample analysis. The constituents of electroplating sludge is Cu (8.34%), Ni (14.37%), Cr (8.83%); minor components for the Zn (1.76%), Fe (1.87%) ; 84.07% moisture content. Cr content is higher in summer and lower autumn (less than 2%); Cu, Ni, Zn and Fe content is stable.Appropriate copper, nickel leaching conditions were identified as follows: electroplating sludge feed fineness of 100 heads, liquid-solid ratio of 5, 8mL sulphate acid per gram was added in sludge, mixing at 30℃, extraction time was 1hr. Under these conditions, copper, nickel leaching rate can reach more than 98%Identified precipitation of Cu2+ suitable pH value range of 4~8. In the pH value of 4 and 8, the copper deposition rate was 1.0% and 99% respectively. N902 was used to extract of copper and conditions were as follows: extraction equilibrium time of 2min, the solution pH value of 1.6 ~ 1.8, extrication concentration of 30%, compared to 1:1. Copper extraction rate of 98.1 percent. Remove impurity ions by Adjust solution pH and temperature control methods. Rough nickel sulphate was obtained by concentrated, crystallization and dehydration dry. The recovery rate of nickel is up to 85%.