No abstract

The palm oil mill effluent (POME) treatment process is exposed to the formation of crystal-like deposits where their accumulation could create a significant threat to achieving an efficient POME treatment. This article reviewed similar occurrences in other industries, discussed factors influencing the crystal formation and suggested possible solutions to be applied in the oil palm industry. From the review, it was found that crystal deposits have always been a nuisance and sometimes a significant threat to similar industries such as industrial, agricultural and municipal wastewater treatment facilities. Other industries where there is a handling process of certain type of fluids such as heat transfer and oil reservoir drilling fluids also faces similar problems. The article also presented the spectrum of methods for mitigation and removal of the crystal formed. For many cases, nutrient recovery through struvite precipitation has become attractive as it not only reduces crystal growth but at the same time prevents excessive nutrients discharge to the environment. Further exploitation of the recovered struvite as a fertiliser source could possibly generate additional income to the oil palm industry.

Palm oil mill effluent (POME) is abundantly generated from the palm oil milling process. Its stringent discharge limits of biological oxygen demand (BOD) of < 20 mg litre -1 has been the most prevalent issue faced in the course of extending palm oil business development. Conventional POME treatment system anaerobically in a series of ponding systems, topped with additional costly tertiary polishing system may not be able to meet this challenging standard due to inconsistent plant performance. A cost-effective POME treatment technology featuring full resource recovery and zero discharge/zero emissions is encouraged. This article examined the performance of an integrated anaerobic-aerobic zero discharge POME treatment pilot system in full operation for a year in a palm oil mill. The assessed system showed 100% compliance to BOD of 100 mg litre -1 and 80% for the more stringent BOD 20 mg litre -1 while generating renewable electricity from the combusted biogas and recycling boiler-grade water via reclamation.