FEED SYSTEM INNOVATION FOR GASIFICATION OF LOCALLY ECONOMICAL ALTERNATIVE FUELS (FIGLEAF)

Swanson, Michael L. ; Musich, Mark A. ; Schmidt, Darren D.

National Energy Technology Laboratory (U.S.)

关键词: Coal Gasification;    Charges;    01 Coal, Lignite, And Peat;    Potential Energy;    Gasification;   

DOI  :  10.2172/792163
RP-ID  :  FC26-00NT40904--01
RP-ID  :  FC26-00NT40904
RP-ID  :  792163

美国|英语

来源: UNT Digital Library

【 摘 要 】

The Feed System Innovation for Gasification of Locally Economical Alternative Fuels (FIGLEAF) project is being conducted by the Energy and Environmental Research Center and Gasification Engineering Corporation of Houston, Texas (a subsidiary of Global Energy Inc., Cincinnati, Ohio), with 80% cofunding from the U.S. Department of Energy. The goal of the project is to identify and evaluate low-value fuels that could serve as alternative feedstocks and to develop a feed system to facilitate their use in integrated gasification combined cycle and gasification coproduction facilities. The long-term goal, to be accomplished in a subsequent project, is to install a feed system for the selected fuels at Global Energy's commercial-scale 262-MW Wabash River Coal Gasification Facility in West Terre Haute, Indiana. The feasibility study undertaken for the project consists of identifying and evaluating the economic feasibility of potential fuel sources, developing a feed system design capable of providing a fuel at 400 psig to the second stage of the E-Gas (Destec) gasifier to be cogasified with coal at up to 30% on a Btu basis, performing bench- and pilot-scale testing to verify concepts and clarify decision-based options, reviewing prior art with respect to high-pressure feed system designs, and determining the economics of cofeeding alternative feedstocks with the conceptual feed system design. Activities and results thus far include the following. Several potential alternative fuels have been obtained for evaluation and testing as potential feedstocks, including sewage sludge, used railroad ties, urban wood waste, municipal solid waste, and used waste tires/tire-derived fuel. Only fuels with potential tipping fees were considered; potential energy crop fuels were not considered since they would have a net positive cost to the plant. Based on the feedstock assessment, sewage sludge has been selected as one of the primary feedstocks for consideration at the Wabash plant. Because of the limited waste heat available for drying and the ability of the gasifier to operate with alternative feedstocks at up to 80% moisture, a decision was made to investigate a pumping system for delivering the as-received fuel across the pressure boundary. High-temperature drop-tube furnace tests were conducted to determine if explosive fragmentation of high-moisture sludge droplets could be expected, but showed that these droplets underwent a shrinking and densification process that implies that the sludge will have to be well dispersed when injected into the gasifier. Fuel dispersion nozzles have been obtained for measuring how well the sludge can be dispersed in the second stage of the gasifier. Future work will include leasing a Schwing America pump to test pumping sewage sludge against 400 psig. In addition, sludge dispersion testing will be completed using two different dispersion nozzles to determine their ability to generate sludge particles small enough to be entrained out of the E-Gas entrained-flow gasifier.