Fossil fuels place a large strain on the environment due to the pollution produced through their extraction and usage. One method to reduce societal fossil fuel usage is through co-combustion of coal with woody biomass. However, overproduction of this biomass may lead to significant environmental deterioration. A potential sustainable substitute for the woody biomass is in the form of dried algae. Because the emission characteristics of algae combustion are unknown, a simple dry mass combustor was constructed, including necessary instrumentation, as part of an undergraduate design class with the goal of a more thorough characterization of algae’s combustion properties. The combustor is a simple and affordable design, in keeping with the classes’ principles of sustainability through a focus on energy, environment, and economy. The combustor consists of a flow controller that sends air into a metallic plenum, where modulations in flow are reduced before it is sent to a steel pipe for combustion. This paper describes the concepts involved in the design of this combustor, and preliminary assessment efforts employing the system when testing biomass pellets. Testing showed combustion efficiency greater than 98%, and the data clearly illustrates three separate phases to the reaction process, with rapid changes in emissions and temperature punctuating the ends of these phases.
Characterization of Inorganic Elements in Woody Biomass Bottom Ash from a Fixed-bed Combustion System, a Downdraft Gasifier and a Wood Pellet Burner by Fractionation
