The effectiveness of used plastic bottles as media in the biofilter for reducing BOD5 and COD in laundry waste

Abstract

Abstract

Used plastic bottles can be used for biofilter media, as microorganisms may attach in the bottle surface. To understand the effectiveness of the number of plastic bottles in the anaerob tank in reducing BOD₅ and COD in laundry waste, a research has been done in October-December 2019. There were 3 treatments applied, namely P₁ (25 bottles,  11.540 cm² surface area),  P₂ (50 bottles, 23.080 cm² surface area) and  P₃ (75 bottles,  34.619 cm²  surface area), with 3 replications in each treatments. The seeding time of the biofilm was 25 days and the retention time of the water was 12 hours. The effectiveness of BOD₅ decrement was 48.4%, 61.1% dan 69.4% in P₁, P₂, and P₃ respectively. While the effectiveness of COD decrement was 44.5%, 50% and61.8% in P₁, P₂, and P₃ respectively. Based on data obtained, it can be concluded that the biofilter that was completed with plastic bottleswas able to reduce the BOD₅ and COD in the laundry liquid waste and P₃ provided the best result.

Keywords: anaerob, bacteri, waste management, plastic bottle re-use