高频气力分选机的风量和给料速度对PCB中多种金属回收率的影响

INFLUENCE OF AIR VOLUME AND FEEDING RATE OF HIGH-FREQUENCY VIBRATION SEPARATOR ON DISTRIBUTION AND RECOVERY RATE OF METALS IN PCB

采用自制高频气力分选机分选废旧电路板粉末(0.125~0.75 mm),通过ICP-AES测定分选产品,研究了风量、给料速度对分选废旧电路板中金属回收率的影响。结果表明:风量对铜、铅、铂、锌、锡的回收率的影响较大。在实际分选回收时,需要选择合适的风量,以免造成金属损失。给料速度存在一个最优区间,在这个区间内,可以得到铜回收率最大值。给料速度对铅、锡、铂的回收率影响较大,在实际分选回收铅、锡、铂的过程中,需结合铜回收率的最优区间选择合适的给料速度,以免造成金属损失;不管研究风量还是给料速度对金属回收率的影响,轻金属铝、镁的回收率都不理想,所以若要分离富集铝、镁须对选后产品进行二次分选,以及在分选过程中选择合适的风量及给料速度,避免其损失。

A self-made high-frequency vibration separator was utilized to separate waste printed circuit board( PCB) powder with the particle size ranging from 0. 125 to 0. 75 mm. The effects of air volume and feeding rate on the recovery rate of different metals in waste PCB were investigated. The separated products were tested by employing ICP-AES. Results illustrated that air volume had great influence on the recovery rate of Cu,Pb,Pt,Zn,Sn and a suitable air volume value was needed to reduce the metal loss in the actual separation. The maximum recovery rate of Cu was obtained in an optimal range of feeding rate,which had great effect on the recovery rates of Pb,Sn,Pt. The optimal range of feeding rate for Cu recovery rate should be considered to avoid metals loss in the actual separation. The recovery rate of light metals( Al,Mg) was not ideal in all the conditions concerned. Therefore, a re-separation was needed for concentrating the light metals( Al, Mg) effectively.Meanwhile,the optimal values of air volume and feeding rate were also needed to avoid their weight losses.