Abstract
Aiming to mitigate wastewater pollution arising from the palm oil industry, this university-industry research-and-development project focused on the integration of serial treatment processes, including the use of moving bed biofilm reactor (MBBR), pre-treatment with sand filters and activated carbon filters, and membrane technology for aerobically-digested palm oil mill effluent (POME) treatment. To assess the potential of this sustainable alternative practice in the industry, the developed technology was demonstrated in a pilot-scale facility: four combinations (Combinations I to IV) of unit operations were developed in an integrated membrane-filtration system. Combination I includes a MBBR, pre-treatment unit comprising sand filters and activated carbon filters, ultrafiltration (UF) membrane, and reverse osmosis (RO) membrane, while Combination II excludes MBBR, Combination III excludes UF membrane, and Combination IV excludes both MBBR and UF membrane. Life cycle assessment (LCA) was performed to evaluate potential environmental impacts arising from each combination while achieving the goal of obtaining recycled and reusable water from the aerobically-digested POME treatment. It is reported that electricity consumption is the predominant factor contributing to most of those categories (50–77%) as the emissions of carbon dioxide (CO2), sulfur dioxide (SO2), nitrogen oxides, and volatile mercury during the combustion of fossil fuels. Combination I in the integrated membrane-filtration system with all unit operations incurring high electricity consumption (52 MJ) contributed to the greatest environmental impact. Electricity consumption registers the highest impact towards all life cycle impact categories: 73% on climate change, 80% on terrestrial acidification, 51% on eutrophication, and 43% on human toxicity. Conversely, Combination IV is the most environmentally-friendly process, since it involves only two-unit operations – pre-treatment unit (comprising sand filters and activated carbon filters) and RO membrane unit – and thus incurs the least electricity consumption (41.6 MJ). The LCA offers insights into each combination of the operating process and facilitates both researchers and the industry towards sustainable production.
Highlights
As the key driver for rural development in Malaysia, the palm oil industry provides direct employment to half a million Malaysians and indirect employment to another 250,000 people
The pre-treated palm oil mill effluent (POME) in the intermediate tank was further treated with the reverse osmosis (RO)-membrane unit and left in a treated water storage tank
High contribution in eutrophication and human toxicity can be observed in both electricity consumption and process water
Summary
As the key driver for rural development in Malaysia, the palm oil industry provides direct employment to half a million Malaysians and indirect employment to another 250,000 people. The industry, has faced environmental challenges since the extraction of palm oil generates sizeable volumes of wastewater known as palm oil mill effluent (POME). The release of untreated POME into water bodies causes environmental pollution by reducing the dissolved oxygen concentration therein, threatening the life of aquatic organisms [2, 3]. Over the past few decades, POME has conventionally been treated with the use of a series of open ponds [4]. This conventional biological treatment suffers from the emission of greenhouse gases (GHS), i.e., methane and carbon dioxide (CO2) [5]. The treated effluent has a high quality and crystal-clear water that can be used as the boiler feed water or as the source of drinking water production [8]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
