Treatment of industrial wastewater using constructed wetland : removal of chemical oxygen demand (COD) and total suspended solid (TSS)

Wastewaters from industrial places are very complex and lead to water pollution if discharged untreated. Palm oil mill effluent (POME) contain high amount of Chemical Oxygen Demand (COD), Total Suspended Solid (TSS) and nutrients. Therefore, wastewater treatment such as constructed wetland is needed to decrease the effect of contamination. Constructed wetland is a wetland that specifically constructed to control pollution from wastewater. The objective of this research is to study the efficiency of constructed wetland to treat pollutant in POME. Parameters concerns are COD and TSS. In this study, lab scale of constructed wetland had been constructed by using water lettuce (Pistia stratiotes) as wetland plant and gravel as filter. This experiment consists of two systems which are without and with cycle. Each system was conducted on four stages; first and third stage used gravel as a filter while second and fourth stage used constructed wetland to remove the pollutant. This experiment was conducted with different concentrations of sample which are 100% concentration and 80% concentration. For the System 1 (without cycle) which is 10 days of treatment, 96.89 % of COD and 96.21% of TSS had been removed from 100% sample concentration while 95.06% of COD and 84.59% of TSS had been removed from 80% of sample concentration. For the System 2 (with cycle) which is 20 days of treatment, the results showed removal of 98.32% of COD and 98.02% of TSS from 100% sample concentration whereas 98.01% of COD and 95.77% of TSS removed from 80% sample concentration. As a conclusion, constructed wetland can be used as industrial waste treatment and also gives high efficiency in removal of contaminant in POME.