Feasibility of palm oil mill effluent elimination towards sustainable Malaysian palm oil industry

摘要

Palm oil mill effluent (POME) is recognised as one of the biggest sources of pollution due to its eutrophying nature and methane emitting treatment. Although biogas recovery and utilisation are promoted through government initiatives, the motivation and support from mills still reported low in Malaysia. This paper aims to discuss the benefits and drawbacks of POME utilisation in the palm oil supply chain based on environmental, social and economic concerns to review the favourability of POME elimination. A zero effluent approach is introduced based on POME evaporation technique, undiluted clarification practice and water recycling strategy as an alternative for conventional POME management approaches. An integrated palm oil complex concept is proposed which includes new palm oil processing approach that eliminates POME and provides industrial symbiosis possibilities within palm oil upstream and downstream sectors to promote sustainability of palm oil industry with balanced economic and environmental advantages. A comparative study between POME utilisation (Case 1 and 2) and POME elimination (Case 3) in different perspectives is included in this work. In the economic view, the payback period of Case 3 is shorter (4 y) compared to Case 1 and 2 (4.3-8.3 y). In comparison, POME elimination technology is more environmentally friendly due to smaller water and land footprint, zero methane emission and minimum waste generation. Approximately 0.3% improvement in oil extraction rate can be potentially achieved by the proposed mill configuration in Case 3. One of the challenges in POME elimination implementation is the additional 0.25 kg steam requirement associated with evaporation of 1 kg water. The study provides insights on the feasibility of the proposed sustainable concept in Malaysia with consideration of government policies and programmes. The suggested POME elimination-based complex provides alternative option to mill owners who are uninterested to invest in biogas capturing facilities.