ABSTRACT
Wastewater from the wood and pulp industry is of environmental concern. It contains high concentrations of organic and inorganic matter. In this work a combined method of coagulation, adsorption and nanofiltration/reverse osmosis (NF/RO) was investigated in the purification of biologically treated wastewater from wood processing. Coagulation with 0.8 g dm(-3) AlCl3 x 6H2O and adsorption on 2.5 g m(-3) modified clinoptilolite tuff resulted in removal efficiencies of total carbon (TC), total organic carbon (TOC) and inorganic carbon (IC) up to 67.1%, 77.4% and 49.5%, respectively. Almost complete removal of solutes was achieved after NF/RO treatment. The TOC removal efficiency with RO membrane (CPA-3, LFC-1, XLE) and tight NF membrane (NF90) was 98% and with highly porous NF membrane (DK), 88%. After the proposed treatment the purified water stream can be recycled into the process or safely disposed to the river.
