Recent advances in industrial water reuse: techno-economic insights into selective reuse and brine segregation in the pulp and paper sector

ABSTRACT

Graphical abstract shows a high level representation of the loops from the main industriewater Eerbeek industrial wastewater treatment plant and the water reuse pilot. it depicts the brine loop 1 recirculation and the minimum liquid discharge of brine loop 2.

Growing pressure on freshwater resources in the Netherlands has increased the need for industrial water reuse, particularly in the water-intensive pulp and paper sector. Conventional end-of-pipe systems based on ultrafiltration (UF) and reverse osmosis (RO) are reliable but remain sensitive to fouling, scaling and variable intake quality. This study evaluates the techno-economic feasibility of a more selective and flexible treatment train. A pilot system combining hollow fibre nanofiltration (HFNF), granular activated carbon (GAC) polishing and electrodialysis reversal (EDR) was operated for 180 days on wastewater from the Industriewater Eerbeek Industrial Wastewater Treatment Plant (IWE WWTP). High removal of colour, chemical oxygen demand (COD) and sulphate was observed at the HFNF system, whilst the EDR showed great flexibility in desalination. Reuse water met all paper mill specifications at the 99th percentile. Selective treatment enabled segregation of organic-rich HFNF concentrate and salt-rich EDR brine. The HFNF concentrate was treated by coagulation and flocculation and recirculated over the WWTP, while the EDR brine was further concentrated and allowed for more research on brine management. Techno-economic comparison showed a total expenditure (TOTEX) of 1.85 EUR/m3 for the innovative system versus 2.14 EUR/m3 for the conventional system. These findings demonstrate a cost-effective pathway toward effective water reuse in end-of-pipe configurations.