Constructed Wetland to Treat Tapioca Starch Wastewater in Indonesia

Abstract

The tapioca wastewater normally is discharged directly into the surface water without treatment processes causing pollution and harmful to the surface water. A constructed wetland to treat wastewater from tapioca starch factory has been built in tapioca factory Sumedang Regency, Indonesia, in December 2015. Every nine days, water samples from both influent and effluent were taken and analysed for COD, BOD₅, O₂, cyanide and total settleable solids. The objective of this study was to find out whether combination of pre-treatment and constructed wetland planted with Phragmiteskarka can meet the discharge requirements corresponding to 150 mg l^–1 biochemical oxygen demand (BOD₅), 300 mg l^–1 chemical oxygen demand (COD), 100 mg l^–1 TSS and 0.3 mg l^–1 cyanide according to Indonesian standard for tapioca industry.The results of this experiment from period from July 2016 to March 2017 showed that the treatment efficiency of BOD₅, COD and total settleable solids were 99.07%, 98.99% and 92.54% respectively, whereas the average concentration in effluent was 17 mg l^–1for BOD₅, COD was 22 mg l^–1and total settleable solids was 51 mg l^–1. The overall results show that BOD₅ and COD concentration in effluent were already far lower than the Indonesian standard for tapioca factory wastewater.