ABSTRACT
The heap leaching technology has several steps: firstly, leaching agent is intermittently automatic sprayed, sprinkled or weir minerals poured in oreheap which has been exploited and broken to a certain size or pelletized and pilled up in the yard where paved with a leak proof layer. Secondly, leaching agent dissolves the useful metal through capillary action and chemical reaction when it goes through the ore. Thirdly, leaching agent, precisely the leaching solution, will be collected when it steams from the pile bottom. Lastly, the leaching solution is sent by pump to the factory to recycle valuable metals (Li 2005). The technology is widely used because of its short process flow, easy operation, less investment, low production cost and the considerable economic benefits. The thesis attempts to advance a comprehensive evaluation index system to evaluate the technical economical effect of the technology.
