Constructed Wetland to Treat Biological Oxygen, Chemical, Total Soluble Salts and Chlorinated Phenol of Pulp and Paper Mill Effluent

摘要

This study evaluated the effectiveness of constructed wetlands for secondary treatment of pulp and paper mill effluent. Three microcosm-scale wetlands were integratively designed and constructed to investigate colour, pollutant and phenol removal to provide future design parameters for pilot - scale constructed wetlands. Each wetland consisted of a 35 cm hydrosoil depth with different layers consist of Pebbles: 6 cm; Gravel: 6 cm; Coarse sand: 7 cm; Fine sand: 7 cm; Soil: 9 cm with 10 cm of water and planted with weeds, Phragmitis australis, Typha latifolia and Cyperus pangorei (25rnshoots m~(-2) individually. Inflow rates to the bench-scale wetlands were controlled by approximately 8 ml min~(-1) to achieve nominal 48 h hydraulic retention time. By using the weed species the BOD of the pulp and paper mill effluent decreased by 77, 74 and 64 per cent, respectively in Phragmitis australis, Typha latifolia and Cyperus pangorei planted wetlands. The COD was decreased 62, 55 and 49 per cent, respectively. The TSS of the effluent decreased by 77, 72 and 67 per cent, respectively. The overall chlorinated phenol degradation of Phragmitis australis, Cyperus pangorei and Typha latifolia planted tubs was 87, 81 and 72 per cent, respectively.