Palm oil mill effluent (POME) as raw material for biohydrogen and methane production via dark fermentation

The Palm Oil industry is growing faster, as the global demand for its products greatly overcomes its production. As palm oil production increases, also does its effluent, Palm Oil Mill Effluent (POME). POME is a complex effluent, which is not toxic, but due to its elevated organic content, it is considered extremely polluting. Generally, POME is submitted to both physical and chemical treatments before being discarded into receiving streams or other water bodies. This process might be costly for the industry and there 98is no income from effluent treatment, therefore another destination for this effluent is desirable. As an alternative, this residue could be exploited as raw material in biological processes, specially hydrogen and methane production, due to the presence of carbohydrates, lipids and proteins that might be metabolized during the dark fermentation process. Hydrogen can be used in different industries, such as chemical, biochemical and food industries. Methane is an important combustible, which could substitute natural gas and hydrogen as a very promising fuel. This review approaches sustainable and renewable processes for POME exploitation as raw material for renewable energy production.