盖着帆布的板很容易被油穿透，但石蜡不能穿透，这样，油就从帆布滴至压滤机下面的槽内。

The canvas covering the plates is easily penetrated by oil, but is impenetrable to the wax, so that the oil drips down from the canvas into a trough beneath the press.

youdao

从油中分离石蜡的过程，首先进行冷冻(帮助生成石蜡晶体)，然后用板框式压滤机在压力下进行过滤。

The process of separating wax from oil by first chilling (to help form wax crystals) and then filtering under pressure in a plate and frame press.

youdao