Spouted Fluid Beds for Mercury Removal from Coal

This Small Business Innovation Research project targets the development of mitigation strategies to decrease mercury and other potential hazardous elements in coal prior to combustion or gasification. The Microbeam team including the University of North Dakota and Envergex, LLC is developing a method of coal beneficiation that not only removes mercury, sulfur and other hazardous trace elements, but also reduces coal moisture and ash-forming components, which are known to have a significant impact on coal-fired plant efficiency. In Phase I we will demonstrate proof-of-concept that mercury and other hazardous elements can be reduced in coals through the use of a spouted bed reactor. The feed coals will be fully characterized to understand their chemical composition, including mercury content. Using information on the prepared coal properties, computational fluid dynamic flow modeling will be conducted to define the design and operating parameters of the spouted bed that effectively separate mercury and other impurities coal from the coal matrix. Laboratory-scale systems will be designed, constructed and tested to demonstrate the removal of impurities from selected coals based on the modeling efforts. The major outcomes of the Phase I project will be the technical performance metrics of mercury removal efficiency. Phase I will also develop the initial high-level feasibility information, such as scale-up, economic and retrofit logistics considerations, that will be crucial to guide further development of the technology. The main benefit of the proposed work will be to facilitate development of cost effective methods to control mercury and other potential hazardous pollutants from coal-fired electric power production. The current regulatory environment is making continued coal use for power production a tremendous challenge. Our technology will enable these plants to continue operations by minimizing mercury emissions without the use of corrosive halogens and carbon-based sorbents in the downstream equipment, while also reducing emissions of other regulated pollutants and increasing plant efficiency to reduce carbon dioxide emissions.