Evaporators for BCTMP Liquor

The liquor from a BCTMP plant has a high COD (Chemical Oxygen Demand) value of 15 to 22 kg/t of water and the specific water consumption of around 10 m³/t of pulp.

It is economically  and environmentally justified to replace the conventional biological effluent water treatment plant with an evaporation system and concentrate combustion in a recovery boiler.

Benefits

• Condensate from evaporation can be used as washing water in the BCTMP process
• Recovery of chemicals
• COD is converted into steam in the recovery boiler

Key features

• Up to 8-effect trains with falling film evaporators
• High DS possible with up-flow falling film concentrator
• Low steam consumption due to flashing of the liquor and condensate from effect to effect
• Excellent condensate segregation

Options

• On-stream washing system for each effect
• MVR falling film evaporators as pre-evaporator