STUDI PENURUNAN KADAR LOGAM BERAT PADA LIMBAH CAIR DARI INDUSTRI PELAPISAN LOGAM DENGAN PROSES KOAGULASI-FLOKULASI

Abstract

ABSTRACT Electroplating process aims to provide rust protection and gives a shiny effect on iron and steel in a way to give a protective layer of metal such as chromium, manganese or copper. This electroplating process produces a lot of waste water containing heavy metals such as chromium (Cr), copper (Cu), manganese (Mn) and iron (Fe) exceeds the quality standard specified in KepMen LH no 51 th 1995. In this study, the treated electroplating wastes contains high levels of chromium, iron, copper and manganese in a row by 92 ppm, 46 ppm, 44 ppm, 9 ppm and pH 2 where the content of the waste has exceeded the quality standard for chromium, iron, manganese and copper successive a row of 0.5 mg/l, 5mg/l, 2mg/l and 2mg/l. Electroplating wastewater treatment process is carried out through a chemical treatment process with coagulant addition of Ca(OH)2 (lime) and Al2(SO4)3 (alum). In addition, prior to the addition of coagulants, is also undergoing a process of waste reduction prior to the end that reduces Cr +6 to Cr +3 by adding a reducing agent KI. Percentage of allowance for optimal content of chromium, iron, copper and manganese for treatment of electroplating waste derived from processing the results of using coagulant Ca(OH)2 (lime), which is preceded by the reduction process using KI. The optimum mass of limes and the reducing agent KI used successively by 4 g and 7 g of producing chromium removal efficiency, iron, copper and manganese in a row for 99.646%, 99.234%, 99.998% and 99.684%. Keyword : Koagulation, floculation, heavy metal, lime, tawas, electroplating