Don’t waste the waste
Apart from housing one of the world’s oldest rainforests, Malaysia is also abundant in palm oil trees, covering over 4.7 million hectares of land for cultivation which makes them one of the largest palm oil producers and exporters worldwide. However, the great harvest comes with wastes that results in global warming.
Palm Oil Mill Effluent (POME), waste water from the production of crude palm oil, produces a huge amount of biogas which otherwise just go into the air. Biogas, contains a huge amount of methane. Methane is proven to have more Global Warming Potential compared to other gases like carbon dioxide (CO2). However, biogas can be upgraded to energy for mills or trucks-on-site by converting it into biomethane. Contrary to belief, burning biomethane does not increase the CO2 emission while burning fossil fuel releases more CO2 into the atmosphere.
The existing separation methods for biogas treatment requires large amounts of energy and generates wastes, which sometimes must be treated before disposal. Even then, the biomethane produced will usually be at low pressure, which is unsuitable to be used directly by gas grid. To resolve this issue, an additional compressor would need to be used. However, this becomes disadvantageous for small scale production plants due to the increased operating costs.
SEPURAN® Green - a hollow fiber membrane modules made up of cylindrical polyimid polymer developed by Evonik, provide an option for the industry to upgrade biogas in an eco-friendly and cost effective manner. Crude biogas, which consists of methane, carbon dioxide and trace gases have different molecules sizes and solubilities in polymers. The hollow fiber membranes, similar looking to a bunch of spaghetti strands, exploits the differences in permeability of gases through the membranes.
As the untreated biogas is introduced under pressure at one end of the membrane, the partial pressures of the gas in the hollow fiber, allows carbon dioxide and water vapour to permeate through the membrane. This results in a high purity methane which is captured in the other end of the membrane. No pressure loss in the product gas also means that this biomethane is now ready to be injected directly to the gas grid.
The new model of using biogas efficiently will conserve valuable resources and increase profits, making it particularly interesting for palm oil millers in Malaysia. Evonik has committed to the sustainable growth of regional biogas industry and plans are in pipelines to step up the presence of SEPURAN® Green in Malaysia. The great harvest just became more valuable.