Micorwave Energy Aided Mineral Comminution

Abstract

Mineral liberation during beneficiation is essentially through comminution. However, the fact that the major slice (up to 50 percent) in the pie for total energy requirements during beneficiation is occupied by comminution, dictates us to look into various possi-bilities to render comminution more energy-efficient. In the early 1900s, efforts for reduction in the crushing and grinding energies based on the concept, 'thermally assisted liberation' (T A L) were made but could not be commercially exploited. With the advent of microwave energy and applications in different commercial operat-ions based on its property of heat generation in materials encouraged it in utilizing as an aid during comminution. Microwave energy heats individual phases in an ore matrix to different heat levels as per individual microwave absorption characteristics. Exposure to microwave energy over discrete time intervals prior to comminution results in development of micro fractures due to differential heating. Weakening of interspatial bonding in the ore matrix helps in lesser energy requirements. Numerous studies on microwave energy applications in the field of mineral processing and extractive metallurgy are under-taken in many parts of the world in recent years.