化学制浆工段提出的浓黑液和稀黑液中含有较多纤维悬浮物，在进入碱回收工段之前，经过黑液过滤机转鼓上的滤网过滤出来，以免影响蒸发效率。本机设有黑液加温装置，以降低黑液粘度，保证过滤机高效正常工作。

Deep Black liquor and dilute black liquor ,that is taken out from chemical pulping section ,enter into black filter press before the alkali recycle section ,to prevent the fibers black liquor suspended objects to affect evaporation efficiency through the turn drum net. The machine has black liquor heating device to reduce viscosity in order to ensure filter press to efficient work normally