Today, rice is one of the most important food crops in the world, and staple for more than half of the global population. Rice is grown and harvested on every continent except Antarctica. The majority of all rice is produced in India, China, Japan, Indonesia, Thailand, Burma, and Bangladesh. Asian farmers’ accounts for 92% of the world's total rice production. According to the FAO statistical database, more than 650 million tons of rice is produced annually around the globe.
Among the rice producing countries, Italy ranks 27th, with a national production rate for paddy rice (Rough Rice: threshed unmilled rice) of 1.49 million tons in the year 2007 and an average grain yield of 6.34 t/ha (Ente Risi, 2007). Nonetheless, this amount represents fully 50% of rice production in the European Union. The EU rice production is continuosly growing in the last years (in 2007 it was about 3.5 million of tons).
Rice husk ash (RHA) is a term describing the waste collected from the particulate collection equipment attached upstream to the stacks of rice husk-fired boilers.
RHA containing 80 to 95% of silica!
COSMOS-RICE (Colloidal Silica Medium, to Obtain Safe inert, from RICE husk ash) project has the aim to re-use RHA to produce silica gel, to be employed in the inertisation of municipal solid waste incinerator (MSWI) fly ash.
This project is proposed on the basis of promising results that have been already obtained for inertisation of MSWI fly ash, during the COMOS project (LIFE08 ENV/IT/000434 www.cosmos.csmt.eu): COSMOS has been selected for for inclusion in Science for Environment Policy, the European Commission's environmental news service for policy makers (http://ec.europa.eu/environment/integration/research/newsalert/pdf/226na4.pdf).
The aim of the new proposed project is to demonstrate that already obtained results can be improved: i.e. inertize MSWI fly ash, using biosilica, produced at lower economical and environmental costs. The following Figure shows the scheme of the final demonstration plant.