A Review on Aerobic Biological Processes for Palm Oil Mill Effluent: Possible Approaches

Abstract

On large scale, many countries like Indonesia and Malaysia receive economic advantage from employing numerous mills to produce and sell palm oil. Despite the benefits, contaminated effluents from palm oil processing have polluted enormous quantities of fresh water, which leads to massive scarcity of fresh water. Moreover, vast quantities of fresh water with steady rainfalls were placed in a country known as Malaysia, but currently, it has massive fresh water wastage because of environmental pollution, and discharging unwell treated palm oil mill effluent (POME). Also, the increasing amounts of POME suffocate agriculture, fresh water, aquatic life, and human health and results in a fantastic medium for bacteria, viruses, and diseases growth. Therefore, palm oil mill effluent receives huge attention since treatment technologies are highly cost, which forces palm oil industries to reuse wastewater in several needs and conserve the available fresh water. Presently, palm oil industries are looking for treatments with low costs, low energy consumptions, and good performance to boost a greener image of palm oil production. This review shows and summarizes most of the possible approaches of aerobic biological treatments to decompose POME, showing their advantages and disadvantages. Finally, this review finds developing a hybrid system comprised from number of aerobic biological treatments can defeat stand-alone technology limitations and improve effluent quality.

Emerging trends in POME treatment and applications: chemical and biotechnological aspects

“…Their impact ranges from eliciting greenhouse gas (GHGs) emissions to endangering aquatic and terrestrial fauna and flora. POME contains very high concentrations of chemical oxygen demand (COD); biochemical oxygen demand (BOD); turbidity and microbial contaminant (Al-Amshawee et al, 2020;Hosseini & Abdul Wahid, 2015;Mohammed & Chong, 2014;Poh & Chong, 2009;Rupani et al, 2010).…”

“…Some of these techniques have reportedly achieved a 95.5% level for effluent discharge limits in 2011 (Liew et al, 2015). About 85% of Malaysian oil milling plants adopt the ponding system for POME treatment (Lam & Lee, 2011;Wu et al, 2010), with some downside of (a) needing long retention periods, (b) large land area for treatment, (c) yielding unsatisfactory levels of BOD, (d) smell and (e) nitrogen, they need low maintenance cost and low operating energy (Al-Amshawee et al, 2020;Chou et al, 2016;Lam & Lee, 2011).…”

“…Protozoans, marshland plants, aquatic plants, and plant seeds have been used in the treatment of POME, but microorganisms (bacteria and fungi) are most preferred (Al-Amshawee et al, 2020;Rupani et al, 2013). Predominantly, the crude oil milling industry favours the aerobic-anaerobic open pond system for the treatment of POME (Chou et al, 2016).…”

“…Predominantly, the crude oil milling industry favours the aerobic-anaerobic open pond system for the treatment of POME (Chou et al, 2016). Microbes capable of self-perpetuation in POME ponds are the ones that can utilize organic and inorganic constituents of POME as a nutrient source to increase their population and size (Al-Amshawee et al, 2020). Suitable microbes can grow and remove these suspended matters depending on environmental conditions, either aerobically (with oxygen) or anaerobically (without oxygen).…”

A review of wastewater bacterial bio oxidation: mechanisms, reactions, and behaviors

“…Aerobic systems have been found to be unable to minimize P and N, but have high rates of organic carbon removal. A conventional WWT system was used to deliver different amounts of dissolved oxygen to trigger all bacterial groups for simultaneous nitrification, denitrification and phosphate removal (SNDPR) [29][30]. Ammonium oxidizing bacteria (e.g., Nitrosomonas) and nitrite oxidizing bacteria (e.g., Nitrospira) [complete ammonia oxidizing bacteria (comammox)] convert ammonia to nitrite through aerobic conditions through a nitrification process [31].…”