Composting of empty fruit bunches in the tower composter – effect of air intake holes

The process of composting empty fruit bunches (EFB) by mixing with activated liquid organic fertilizer (ALOF) is an alternative utilization of solid waste generated from palm oil mill. This study aims to find composting techniques of EFB and to obtain degradation data of composting EFB by varying the air intake holes to produce good quality compost. Composting process was carried out by tearing the EFB into four shreds, then put into the tower composter while adding ALOF until it reached the optimum moisture content of 55 -65%. During the composting process, we maintained moisture content at optimum conditions by adding ALOF. Variations of air intake holes area to the outer surface area of the composter are 0/44.314; 72.39/44.314 and 144.78/44.314 (cm²/cm²). Composting is carried out for forty days, however, based on the result, compost began to mature on the 10^th day. The results revealed that there was an influence of air intake holes to the composting process. The best degradation of EFB was obtained on the variation of air intake holes 72.39/44.314 (cm²/cm²), pH 8.1, moisture content 79.14%, water holding capacity 60%, electrical conductivity 4.725 dS/m and C/N ratio 20.97.