Waste oil palm trees (WPT) as a resource: assessementof environmental sound technologies from conversion of waste palm trees into potential products

A baseline study on the quantity, characteristics and current uses of these WPT at commercial, pilot scale and R&D level in Malaysia were carried out. The results showed that the projected WPT availability within the next 20 years looks very promising with maximum availability of 200,803 ha in year 2022.This will generate dried biomass material of about15.2 million tonnes. The WPT biomass will contribute about 18.6% of the total biomass generated annually in Malaysia. In perspective, Malaysian WPT biomass generated compares to about 4.24% of total biomass generated in China; 37% of Korea and 72.6% that of Thailand.Being lignocellulosic in nature that is similar to wood, the WPT biomass offers numerous options to be utilized into value added products similar to wood. However, properties such as high moisture contents and fibrous nature makes it difficult to be utilized by the established wood based industries in Malaysia. In general, the types of the products from WPT that have potential to be developed but are still at R&D stage include panel products, sugar, chemical derivatives, bio-ethanol, pulp and paper and dietary supplement. The potential products being taken up by the industries at pilot scale stage and commercial production include plywood, lumber, flooring, micro-crystalline cellulose and animal feed pellets.Products developed from WPT are able to sequester carbon dioxide directly and indirectly for a better environment. Calculated GHG emission from one OPT using equations derived from the UNFCC document with some modifications found that the average amount of CO2 emitted from the decomposition of WPT annually available in year 2011-2032 is equivalent to 14.19 million tonnes of CO2. The amount of CO2 that can be sequestered from the manufacture of the potential products was also calculated. Assuming 50% (about 8.7 million trees) of the annually available WPT in Malaysia is converted into these products, it was estimated that converting the WPT into plywood/flooring; bioethanol from sap; timber and animal feed & micro-crystalline cellulose and timber would be able to reduce GHG emissions by 8.11 %; 1.95%; 21.35% and 20.50% respectively. With additional consideration of current and future market demand it was found that a combination of bio-ethanol and fuel pellets produced from the WPT when used as a replacement for fossil fuel gave better carbon offsets of 39.87%. Therefore, the most environmentally sound technologies (EST) for converting waste palm trees into an energy resource consist of conversion of WPT into two types of products; bio-ethanol from oil palm trunk sap and fuel pellets from the sap squeezed residues.