A biorefinery is a facility that integrates biomass conversion processes and equipment to produce fuels, power, and value-added chemicals from biomass. Biorefinery is analogous to today’s petroleum refinery, which produces multiple fuels and products from petroleum. By producing several products, a biorefinery takes advantage of the various components in biomass and their intermediates, therefore maximizing the value derived from the biomass feedstock.
A biorefinery could, for example, produce one or several low-volume, but high-value, chemical products and a low-value, but high-volume liquid transportation fuel such as biodiesel or bioethanol. At the same time, it can generate electricity and process heat, through CHP technology, for its own use and perhaps enough for sale of electricity to the local utility. The high value products increase profitability, the high-volume fuel helps meet energy needs, and the power production helps to lower energy costs and reduce GHG emissions from traditional power plant facilities.
Working of a Biorefinery
There are several platforms which can be used in a biorefinery with the major ones being the sugar platform and the thermochemical platform (also known as syngas platform).
Sugar platform biorefineries breaks down biomass into different types of component sugars for fermentation or other biological processing into various fuels and chemicals. On the other hand, thermochemical biorefineries transform biomass into synthesis gas (hydrogen and carbon monoxide) or pyrolysis oil.
The thermochemical biomass conversion process is complex, and uses components, configurations, and operating conditions that are more typical of petroleum refining. Biomass is converted into syngas, and syngas is converted into an ethanol-rich mixture. However, syngas created from biomass contains contaminants such as tar and sulphur that interfere with the conversion of the syngas into products. These contaminants can be removed by tar-reforming catalysts and catalytic reforming processes. This not only cleans the syngas, it also creates more of it, improving process economics and ultimately cutting the cost of the resulting ethanol.
Biorefineries would help utilize the optimum potential of wastes and help solve the problems of waste management and greenhouse gas emissions. Each of these three components could be converted, through enzymatic/chemical treatments into either hydrogen or liquid fuels. The pre-treatment processes involved with these, generate products like paper-pulp, HFCS, solvents, acetate, resins, laminates, adhesives, flavour chemicals, activated carbon, fuel enhancers, undigested sugars etc. which generally remain untapped in the traditional processes.
Prospects in MENA
The MENA region has significant biomass energy potential in the form of municipal wastes, crop residues, industrial wastes etc. Around the region, pollution of air, water and soil from different waste streams continues to grow. The major biomass producing countries in MENA are Egypt, Saudi Arabia, Yemen, Iraq, Syria and Jordan. Traditionally, biomass energy has been widely used in rural areas for domestic purposes in the MENA region, especially in Egypt, Yemen and Jordan. The escalating prices of oil and natural gas, the resulting concern over energy-security, have led the MENA nations to explore alternative sources of energy. Biorefinery offers a plausible solution for augmenting energy supply, obtaining clean energy and production of a wide range of chemicals from a host of waste material, apart from associated waste management benefits.