PENURUNAN COD, BOD, TSS, AMONIA DAN KOLIFORM AIR LIMBAH RUMAH POTONG HEWAN DENGAN BIOFILTER AEROBIC FIXED-BED REACTOR DAN KLORINASI

Slaughterhouses produce wastewater containing high organic matter, which has the effect of polluting water and the surrounding environment. Slaughterhouse wastewater treatment can be done biologically, namely biofiltration, by utilizing microorganisms and chlorination. Efforts in wastewater treatment continue to be developed. This study aimed to determine the effectiveness of biofiltration processing techniques with an Aerobic Fixed-Bed Reactor (AFBR) with pumice stone media combined with chlorination to reduce the levels of COD, BOD, TSS, ammonia, and coliform bacteria. The method applied was to use biofilms from the seedings on pumice with variations of with or without the addition of active suspension, aeration system treatment with time variations, and the addition of chlorine with variations of active chlorine doses. The results showed that the addition of active suspension in the process produced the best biofilm, and was effective in reducing the levels of COD, BOD, TSS, and ammonia. The best reduction of COD levels was at the 36th hour at 81.60 mg/L with an efficiency of 57.45%, BOD at the 36th hour was 24.67 mg/L with an efficiency of 65.74%, TSS at the 42nd hour was 54.0 mg/L with an efficiency of 85.66%, and ammonia at the 42nd hour of 1.5539 mg/L with an efficiency of 88.29%. Chlorination after the treatment with AFBR resulted in a decreased number of coliform bacteria from 1,100 MPN/100 mL to 0 MPN/100 mL with 100% efficiency. The chlorination process resulted in the optimum chlorine dose of 165 ppm with a chlorine residual of 28.80 mg/L. Thus, the treatment for 36-42 hours on AFBR followed by chlorination with a chlorine dose of 165 ppm was relatively effective in reducing COD, BOD, TSS, ammonia, and coliform levels of bacteria in slaughterhouses wastewater. Keywords: ammonia, biofiltration, chlorination, coliform.