Implementation of Anaerobic Process on Wastewater from Tapioca Starch Industries

The objective of this research is to study the effect of tapioca starch wastewater industries as substrate on an anaerobic fixed bed digester to the biogas production and to study the performance of 2.25 m fixed bed digester. The research was conducted from February-November 2000 in Situraja, Sumedang, West-Java the benefit of this research is to obtain environmentally sound technologiest in the tapioca starch production-utilizing cassava roots as raw material and to supply additional energy within tapioca starch industries. Method used in this research is the utilization of a fixed bed polyethylene bioreactor of 2.25 m capacity. Support materials/media used was PVC pipe with the dimension of 65.5 mm length, 75 mm diameter, 1.5 mm wall thickness, and have surface area per volume/specific surface area of 45.32 m/m with void volume of 93.5%. The inoculum utilized was filtered cow dung. The performance anaerobic process was done by Chemical Oxygen Demand (COD) controlling, biogas production measurement and methane content measurement. Chemical analyses was done in terms of pH, COD and biological analyses was done in terms of Biochemical Oxygen Demand (BOD). The research results showed that the value of organic substance in the influent was in average of 10,062 ppm and 5,649 ppm in terms of COD and BOD respectively. Maximum organic loading rate applied was 7.8 kg COD/m day. The efficiency degradation reached in average of 76% and 95.8% in terms of COD and BOD respectively. Methane content in the biogas was in the range of 53.5% to 71%. The average biogas productivity was 1.2 m /m of wastewater. Significantly increasing of pH value has been proven from around 4 in the influent and 7.04 to 7.13 in the effluent.