Treatment of Selected CTMP And BCTMP Effluents By Ultrafiltration, 1992 Environmental Conference Proceedings

In the past few years, the pulp and paper industry has experienced a rapid growth in the application of Chemi-Thermo-Mechanical Pulping processes (CTMP), most notably the Bleached Chemi-Thermo-Mechanical Pulping process (BCTMP). During the same period, effluent limitation guidelines have become increasingly stringent. Consequently, the CTMP and BCTMP mills are now faced with a critical technical and economical challenge: to substantially reduce the discharge of pollutants into the receiving environment without compromising theircompetitiveness. To meet this challenge, researchers are presently evaluating innovative water management schemes involving both end of pipe effluent treatment technologies and internal process modifications. Significant research efforts are currently being directed towards the integration of new separation processes into the wastewater and process water circuits of the mills. Such processes will be necessary for the closed-cycle scenarios, anticipated by industry for the medium term future in the CTMP/BCTMP sectors. Among the separation processes being evaluated, ultrafiltration (UF) and nanofiltration (NF) ate attracting significant interest.