| The disposal and treatment of wasted computers become a hot—topic in solid waste research field increasingly, and the wasted computer circuit boards is one of the most primary study objects. For some limitation, this paper mainly discusses the recovery of the valuable components from waste computer circuit boards and presents some suggests on the recovery of the most important valuable metal copper.This paper studies the equipments and techniques of the recovery of wasted computer circuit board through physical method including the fragmentation and separation of wasted circuit board, separate metals and nonmetals through dry and wet method, etc. Wasted circuit boards are crashed by pulverizer, metals and nonmetals can be separated through filter and liquid floatation. The distribution of the objects on each granularity and the liberation degree of metals are studied on different parameters. The recovery status of copper among metals is studied by chemical method after the metals has been liquid floated.The feasible broken time and rotate speed of pulverizer is achieved by accumulative efficiency curve of the filtered objects on each granularity on condition of different broken time and rotate speed. The liberation degree of copper among each granularity on different parameters is reckoned by observe the objects through microscope. The liberated condition between metals and nonmetals is analyzed quantitatively through liquid floatation. The percentage of copper in metal deposition is determined by iodine quantity method. The result of experiment suggests: when the rotate speed is over 2000rpm and the broken time is 120 seconds, the outcomes filtered through liquid tribromomethane(CHBr3) floatation, the highest recovery rate of copper is 97.89% between 0.84-0.42mm granularities; the copper in circuit board mainly enriches in medium granularity, and there are most nonmetals such as fiberglass and carborundum etc. when the objects' granularity are below 0.074mm.
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