The Siam Cement Biomass Project involves the modification of five cement manufacturing plants in Thailand to enable them to use renewable biomass fuel in place of fossil fuels, leading to substantial greenhouse gas emission reductions as well as significant environmental and socio-economic benefits.
The cement plants previously burned a mix of fossil fuels in their kilns, including coal, lignite (brown coal), pet-coke, and heavy fuel oil. With the implementation of the project these have been largely replaced by renewable biomass from a variety of sources – primarily rice husks but also wood-processing residues and other agricultural waste such as palm trunks, palm fibre and palm nut shells.
Supply chains have been established for the sourcing of waste biomass from nearby areas. Prior to the implementation of the project, rice husk was typically burnt in open fields, which is common practice for rice husk waste in developing countries. Other agricultural wastes were left in the fields to decay.
The costs of modifying the existing plant and establishing the new supply chains were substantial, and there were also significant technology risks and technical know-how barriers as the Siam Cement Group was the first company in Thailand to adopt the new technology. The additional revenue from the sale of carbon credits provided the necessary incentive to justify this investment. Without the carbon revenue the project would not have gone ahead.