Effect of Cutting Size in the Composting Process of Oil Palm Empty Fruit Branches (EFB) Using Active Organic Liquid Fertilizer (AOLF) as Co-Composting

Chemical Engineering Department, Faculty of Engineering, Universitas Sumatera Utara, Jalan Almamater Kampus USU, Padang Bulan, Medan 20115, Indonesia

^* Corresponding author: rivaldi@usu.ac.id

Abstract

The size of organic waste materials plays a pivotal role in the composting process, influencing parameters such as decomposition rate, microbial activity, aeration, and nutrient availability. Currently, the study of compost has focused on the degradatiom of organic matter. The study began by varying the sizes of oil palm EFB to 1-3, 3-5, and 5-7 cm. Subsequently, the EFB were placed into a basket composter (33 cm length x 23 cm width x 40 cm height), and active organic liquid fertilizer was added to achieve a moisture content of around 55-65%. The observation period lasted for 60 days. Throughout the composting process, the moisture content was maintained at 55-65% by adding active organic liquid fertilizer, and the composter was turned every 3 days. Analyzed parameters during the composting process included temperature, pH, volatile suspended solids, electrical conductivity, and water holding capacity. The best results were obtained with a cutting size of 3-5 cm, yielding the following values: temperature 26.75 °C, pH 7.5, volatile suspended solids 211,640 mg/L, electrical conductivity 4.05 dS/m, and water holding capacity 65%.