Flue gas purification and heat recovery: A biomass fired boiler supplied with an open absorption system

A new technique for energy recovery combined with particle separation from flue gas has been tested in this project. A conventional small boiler for biofuel produces besides heat also particles to the environment through the flue gas. Decreasing the impact on the environment is desirable. Increased efficiency can be obtained if the temperature and water content of the flue gas can be further reduced. Installing an open absorption system in the heat production unit fulfils both these demands. An experimental unit has been built and tested in the last 2 years. The results show a reduction of particles in the flue gas by 33–44% compared to the ordinary system. At the same time the heat production from the unit increased by 40% when fired with wet biofuels.