EFFECT OF BLENDING VARIOUS COLLECTORS AT BULK FLOTATION OF COPPER AND COBALT SULPHIDE ORES FROM NKANA CONCENTRATOR

Abstract

Nkana Concentrator under the ownership of the then Zambia Consolidated Copper Mines Ltd (ZCCM) had been using Sodium Ethyl Xanthate (SEX) mainly as a collector, but with the coming of new Mopani Copper Mines Plc (M.C.M), it was felt that there was a need to test alternative collectors in an attempt to improve the production of the copper and cobalt concentrates. This work reports a series of laboratory testworks which were conducted on four other collectors which included, Potassium Amyl Xanthate (PAX), Sodium Isopropyl Xanthate (SIPX), Phosphorodithioic acid, O,Odiethyl ester, sodium salt or Ethyl - dtp-Na (DANAFLOAT 123) and Phosphorodithioic acid, O,O-bis (2-methylpropyl) ester, Sodium salt or i-butyl-dtp-Na (DANAFLOAT 245). The parameters considered in the evaluation were grade and recovery of both copper and cobalt minerals. Bulk float was characterised by an improvement in grades and recoveries by use of both individual collectors and their blends. Most collectors performed well except for SIPX and SEX: SIPX for the 20:80 ratio which did not give improved grades. Cobalt grades at bulk float were very poor, well below that obtained from the plant practice. It was established that the use of the other reagents such as PAX, SIPX, DANFLOAT123, DANAFLOAT 245 would be costly as compared to SEX. Cost of DANFLOAT 245 and 123 are $1.28 and $1.33 per kg respectively as compared to SEX at $1.23 per kg whereas SIPX and PAX are also slightly higher than SEX making them less favourable. Keywords : Collectors, recovery, grade, flotation. African Journal of Science and Technology Vol.5(1) 2004: 57-66