Innovative Use of Minerals Processing Technologies for Remediation of Contaminated Soils and Other Wastes

摘要

Most recent developments in environmental management have resulted in public and scientific attention being focused on 'contamination' of industrial sites and on hazardous waste disposal in general. The consequence has been the growth of what might be termed the 'environmental remediation industry'. Scrutiny of the types of 'remediation' being undertaken and the types of process flowsheets being developed reveals that many, if not all, of the unit operations being employed are commonplace minerals processing operations that have been used for years in the mining and minerals processing industries. It appears that these flowsheets are being designed by engineers or others with limited experience of minerals processing or metallurgy. The drawbacks that result from this inexperience are compounded by the fact that many new advances or innovations in mineral technology are being overlooked and the technologies are not being transferred to the modern remediation strategies as they should be. A derived generic flowsheet that incorporates many of the published remediation flowsheets has been used as a commencement point for the present investigation. Common sources of some contaminants are reviewed as part of a simple environmental risk analysis model. Some of the unit operations employed in typical remediation plants and three specific contaminant separation processes are highlighted. These methods are described in more detail and the potential future impact that these innovations may have is noted, including: 1. particle-size classification in the low-micrometre size range; 2. very fine particle flotation, including the identification of a potentially exciting new method of 'ion flotation'; 3. the flotation of chemical precipitates; and 4. a review of the future possibilities of ion-exchange technology in the remediation industry. It is reflected that the expertise possessed by minerals processing/metallurgical professionals provides an opportunity for them to transfer some of their know-how and technology to a new and growing industry.