Membrane‐Based Treatment of Pulp and Paper Industry Wastewaters

Abstract

In this article, the use of pressure‐driven membrane filtration processes in the treatment of pulp and paper mill process and wastewaters is discussed. The article describes the characteristics of the waters and presents information relevant to optimal membrane and module choice in pulp and paper mill applications. Practical examples of membrane processes that are currently used at mill sites are also reviewed. The literature survey reveals that the pressure‐driven membrane processes have secured their position as a key technology in the treatment of pulp and paper industry process and wastewaters. They have been adopted with the aim of decreasing water consumption, recovering and recycling valuable compounds, and reducing the environmental impact of pulp and paper mills. It also seems that the use of pressure‐driven membrane processes will increase as the pulp and paper industry seeks to produce new products from compounds present in process and waste streams. Recovery, fractionation, and concentration of these compounds by membrane processes have proven to be very effective. Moreover, the tightening requirements for improved environmental protection will increase a need to close water cycles and increase the use of membrane processes at pulp and paper mills. The examples of industrial‐scale membrane applications show that membranes can already be used cost‐effectively. To further improve cost‐efficiency, one of the most significant future research needs is the development of novel membranes with lower fouling tendency, improved fractionation capacity, and improved resistance to conditions prevailing in pulp and paper mills and in wood‐based biorefinery processes.