MICROWAVE PROCESSING AS A GREEN AND ENERGY EFFICIENT
TECHNOLOGY FOR THE PRODUCTION OF ENERGY AND
CHEMICALS FROM BIOMASS AND ENERGY CROPS
Brigid Lanigan, Vitaliy Budarin, James Clark, Fabien Deswarte, Peter Shuttleworth, Ashley
Authors address: Green Chemistry Centre of Excellence, Department of Chemistry,
University of York, YO10 5DD, UK
Authors Email: email@example.com
Renewable energy sources are a vital tool in the sustainable development of our growing
society. They enable us to meet our ever growing energy requirements while reducing the
environmental impact of its production. The increasing cost and falling supplies of oil have,
in recent years, buoyed the merits of producing energy from renewable resources. Among the
several options available, a lot of attention has been focused on the production of energy
through the co-firing of biomass with coal in existing power stations.1 Biomass can be used
as a fuel for energy production, through direct combustion, but due to the inherently high
moisture content and oxygenated nature of the solids the calorific value is much lower than
fossil fuels currently in use.2 The aim of this project is to increase the calorific value of
biomass through microwave processing prior to use for energy production. Overall the
process is more energy efficient as microwave irradiation heats the whole volume of a sample
while conventional heating heats the sample in contact with the reaction vessel before the
bulk.3 Results have shown that microwave pretreatment can result in a char with a higher
energy value per unit mass than the starting material. The process allows careful control of
the properties of the resultant material while producing both primary extractives and pyrolysis
oils which can be easily separated. Results have shown the ability to increase the yield of
primary oil to 40 % from oil rich biomass compared to 22 % available by conventional
extraction methods. A secondary pyrolysis oil and high calorific value char are also formed
in sequence with the extraction. Favourable results have been found for a wide variety of
biomass. The energy used in this process and the relative increase in the energy value of the
product is also considered.
1. Demirbas, A., Sustainable cofiring of biomass with coal. Energy Conversion and
Management 2003, 44, (9), 1465-1479.
2. Demirbas, A., Potential applications of renewable energy sources, biomass
combustion problems in boiler power systems and combustion related environmental issues.
Progress in Energy and Combustion Science 2005, 31, (2), 171-192.
3. Kappe, C. O., Controlled Microwave Heating in Modern Organic Synthesis. Angew.
Chem. Int. Ed. 2004, 43, 6250 - 6284.