| 摘要 |
<p>A grinding machine 1 incorporating means, such as a moving band filter 10 comprising a strip 9 of filter paper, for separating metallic and abrasive particles from an oily coolant liquid for the grinding operation, further includes a pair of counter-rotating rollers 15 to which the separated solid is fed and which squeeze further liquid therefrom, the separated liquids being combined and recycled. The squeezing comprises the first stage in a separation process further including extraction of remaining liquid with a solvent in the vapour phase, reduction of iron oxides in the solid by heating in a reducing atmosphere, crushing and magnetic separation of ferrous material from non-ferrous impurities. <IMAGE></p> |
