Energy & Fuels, Vol.25, No.12, 5786-5790, 2011
Physicomechanical Properties of Rice Husk Pellets for Energy Generation
The use of biomass for energy generation is a promising alternative due to its potential to satisfy environmental compatibility. Rice is one of the world's most important food crops. Processing of paddy leads to the generation of crop and agro-industrial wastes, which are voluminous and difficult to handle. By upgrading this biomass into a uniform compressed fuel, namely pellets or briquettes, its density increases, improving the storage, transportation, and combustion characteristics. In this study, densification characteristics of Brazilian rice husks were studied using a laboratory compactor, Hosokowa Bepex, Type L200/50GpK, for the production of pellets. Experiments showed that their bulk density in raw form increased 6.3 times. The effects of different particle sizes (rice husks milled with 2 mm, 4 mm, and 6 mm sieve meshes) and moisture contents (17%, 19%, and 20%) on the durability of the rice husk pellets were assessed. It was concluded that rice husk pellets with 17% water content and made of raw material ground with 2 mm, 4 mm, and 6 mm sieves are durable and stable and comply with the standard quality values of agricultural pellets as specified in Agro and Agro+. Biomass conversion technologies, using pellets, might facilitate the development of decentralized energy systems in rural areas. Nevertheless, in order to be deployed in an efficient and responsible way, economic, technical, environmental, and social aspects over the whole supply chain should also be taken into consideration.