Conventional methods and emerging wastewater polishing technologies for palm oil mill effluent treatment: A review

Abstract

The Malaysian palm oil industry is a major revenue earner and the country is ranked as one of the largest producers in the world. However, growth of the industry is synonymous with a massive production of agro-industrial wastewater. As an environmental protection and public health concern, the highly polluting palm oil mill effluent (POME) has become a major attention-grabber. Hence, the industry is targeting for POME pollution abatement in order to promote a greener image of palm oil and to achieve sustainability. At present, most palm oil mills have adopted the ponding system for treatment. Due to the successful POME pollution abatement experiences, Malaysia is currently planning to revise the effluent quality standards towards a more stringent discharge limits. Hence, the current trend of POME research focuses on developing tertiary treatment or polishing systems for better effluent management. Biotechnologically-advanced POME tertiary (polishing) technologies as well as other physicochemical methods are gaining much attention as these processes are the key players to push the industry towards the goal of environmental sustainability. There are still ongoing treatment technologies being researched and the outcomes maybe available in a while. However, the research completed so far are compiled herein and reported for the first time to acquire a better perspective and insight on the subject with a view of meeting the new standards. To this end, the most feasible technology could be the combination of advanced biological processes (bioreactor systems) with extended aeration, followed by solids separation prior to discharge. Chemical dosing is favoured only if effluent of higher quality is anticipated.

Recovery of Residual Oil From Palm Oil Mill Effluent Using Polypropylene Nanofiber: A Field Trial

“…It is fully owned subsidiary of KLSE public listed company of Kretam Holding Berhad.Three main sources of wastewater that make up of the POME, namely the hydro cyclone (4%), sterilizer condensate (36%) and sludge clarifier (60%) (Liew et al, 2015), the raw effluent combined and discharge to digestion ponds or other treatment methods. The recovery will be done continuously at the pit before enter into ponds, the quality and quantity of the emulsified oil and grease recovered will also be studied.…”

Palm Oil Mill Effluent Tertiary Treatment By Physicochemical Treatment Using Ferrous Sulphate

“…Besides, the present biological based tertiary treatment will require periodic cleaning to clean-up the bio-media that will always choke-up after more than a year in operation that is very laborious in nature, time consuming and costly [7,8,10] . Physicochemical tertiary plant will consist of chemical preparation and dosing facility, clarifier or sedimentation tank and sand filter unit is expected to cost much lower than the biological tertiary treatment plant.…”

“…Fenton oxidation has been applied to polish biologically treated POME that able to reduce the biological loads as well as the colour reduction, while hydrogen peroxide photolysis method has been in used that produced almost similar results [10]. Another researcher has studied metal coagulants such as Ferric Chloride, Aluminium Sulphate and Polyacrylamide for the tertiary treatment process, but only focused on colour reduction of the treated effluent [11,20].…”

Aerobic Post-treatment of Different Anaerobically Digested Palm Oil Mill Effluent (POME)

“…The combination of these biological treatment system required large surface area to allocate a series of pond or lagoon due to longer operational HRT. Thus, physio-chemical treatment such as menbrane filtration, advance oxidation and coagulation-flocculation process could be included to emphasize the discharge limit compliance [7]. …”