Applications of microwave heating in mineral processing

Many minerals are effective absorbers of microwave energy, whereas in general gangue materials are not. This suggests applying microwave heating to mineral processing to effect selective heating of minerai phases. Many mineral processing applications have been tested only on a laboratory scale; the engineering realities of large-scale operations have largely been overlooked. Of particular concern are the modest power outputs of industrial magnetrons relative to the power requirements in mineral processing operations, the high capital cost of microwave equipment and the poor penetration depth of microwaves. Review of these applications, and comparison with guidelines developed for successful microwave technology transfer, suggests that niche areas for microwave heating are in the processing of low-throughput concentrates, especially where volumetric heating leads to enhanced rates of energy transfer. The use of combined heating sources should be Investigated.