Method for Co-Feeding Biomass and Coal for Gasification

Almost all of the energy consumed by the U.S. comes from fossil fuels. Essentially alltransportation fuels come from oil and most electricity is generated from coal. With essentiallyall transportation fuels coming from petroleum, and 70% of electricity coming from coal ornatural gas, it is economically and strategically in the best interest of the U.S. to developtechnologies that permit the increased use of renewable resources for producing transportationfuels and generating electricity. Because the U.S. has enough coal reserves to last about 200 years at current consumption rates, coal will be a part of our energy future. The problem of course, is that this will generate largeamounts of CO2 if the coal is simply burned or gasified. One way to decrease the amount of CO2generated when using coal, is to co-feed it with a renewable carbon source such as biomass. Thebiomass is carbon neutral, since the CO2 released when biomass is burned or gasified (or the fuelmade from biomass is burned), eventually ends up being used to grow more biomass. This is anindirect way of utilizing solar energy (which provides the energy needed by the plants to convert CO2 into cellulose) as a way to augment the production of power and fuels from coal.Future systems that convert coal into electricity or fuels will probably be gasification based,because they are clean, efficient and produce a concentrated stream of high-pressure CO2 that is relatively easy to capture for sequestration. Over 500 million tonnes of agricultural residues are produced yearly, and this biomass could be co-fed to the gasifier to reduce overall CO2 emissions. However, biomass is bulky and it is very expensive to transport it to a centrally located gasifier. Further, its bulkiness and fibrous nature makes it difficult to feed to the gasifier. In many cases, the feed system has to be custom tailored to a specific biomass feed, making the system operate poorly when the biomass feedstock is changed. TDA Research Inc. (TDA) proposes to novel method to pre-process and co-feed biomass and coal to a gasifier. Commercial Applications and Other Bene