Experimental study of microbial desulphurisation of sulphide ores combined with gel foam retardants to prevent spontaneous combustion

Abstract

ABSTRACT The purpose of this study was to reduce the propensity for spontaneous combustion of sulfide ores through the combined action of microorganisms and inhibitors and to assess the flame retardant effect. The sulfide ore samples were first pretreated with biodesulphurisation. The samples were then sprayed with a foam blocker to prevent re-oxidation of the ore and further reduce the spontaneous combustion tendency of the sulfide ore. The experimental results showed that the highest desulfurization rate of 24.26% was achieved for ore samples with a particle size between 140–160 mesh. A combination of 0.05% hexadecyltrimethylammonium bromide (CTAB), 0.11% lauramidopropyl betaine (LAB-35), 0.13% sodium alcohol ether sulfate (AES), 0.11% propanetriol foam stabilizer, 7% water glass and 3% sodium bicarbonate arresting agent was the most effective. The oxidation weight gain of the desulphurised ore sprayed with the resist was only 3.16%. The oxidation weight gain of the desulphurised ore without the addition of the resist was 3.98% and the oxidation weight gain of the undesulphurised ore was 6.01%. This method is effective in reducing the tendency of spontaneous combustion of sulfide ores.