Effect of cellulase addition on leachate recirculation for leachate qualities using bioreactor landfill method

Abstract

Lignocellulose material which consists of three main components, including cellulose, hemicellulose, and lignin, is known for its difficulty to be degraded using biological process using biological process. Cellulase has proven to catalyze the degradation of celullose by enzymatic hydrolysis. However, the addition of cellulase might affect leachate qualities that was generated from landfill. The aim of this research is to analyze the effect of cellulase addition on leachate qualities. Two 1.5 m-height bioreactors were provided for two different treatments including (1) leachate recirculation with cellulase addition (2) leachate recirculation only as control. The addition of cellulase at 15 x 106 U/tonne was resulting in lower concentration for COD (29,100 mg/L in cellulase addition and 31,900 mg/L in control), TS (17,800 mg/L and 22,100 mg/L, respectively), TDS (15,900 mg/L and 19,800 mg/L, respectively). This was likely caused by acceleration of hydrolysis using enzymatic process. However, BOD value higher when cellulase addition was conducted (16,100 and 11,600 mg/L, respectively) because the addition of cellulase supported formation of glucose, therefore escalated BOD value. pH value was increasing over time towards neutral, indicating landfill had been heading toward methanogenic phase. From the experiment, it can be concluded that addition of cellulase has impacts towards leachate qualities