PDF Publication Title:
Text from PDF Page: 309
deterioration. Higher hydrocarbons are assumed to be pre-reformed to hydrogen and carbon monoxide in a mild reformer51 to avoid "sooting" or carbon deposition within the fuel cell. Because both the desulfurization and reforming require elevated temperatures, the fuel is fed through a series of heat exchangers that recover heat from the fuel cell exhaust stream (streams 13 to 20). Humidification steam (stream 3) is added to the fuel to provide the required moisture for the reforming and water-gas shift reactions. The heated and humidified fuel is desulfurized in a sorbent bed and partially reformed in a mild reformer catalyst bed. The balance of the reforming will occur between the stages of the multi-stage fuel cell module. The hot desulfurized and partially reformed fuel stream (stream 7) enters the fuel cell anode at approximately 500 oC (930 oF). Ambient air (stream 9) is compressed to 3.5 atmospheres and 175 oC (347 oF) (stream 10), and subsequently heated to 500 oC (932 oF) prior to entering the fuel cell cathode (stream 11). The hot processed fuel and the compressed ambient air are electrochemically combined within the fuel cell module. The fuel hydrocarbons still remaining after the mild reformer are reformed within the fuel cell. The heat required for the endothermic steam reforming reactions is supplied by the exothermic fuel cell reactions. The overall reactions are exothermic, and the fuel and oxidant temperatures rise to 999 oC (1830 oF) (streams 8 and 12). The fuel cell is capable of utilizing both H2 and CO as fuel and has an overall fuel utilization of 94 percent. The spent fuel (stream 8) and oxidant (stream 12) are combusted upon exiting the multi-stage fuel cell module. The resulting exhaust stream (stream 13) has a temperature of 1119 oC (2046 oF) before being cooled in a fuel heater and expanded to 1.04 atmospheres and 856 oC (1573 oF) (stream 15). This nearly atmospheric exhaust stream passes through several additional heat exchangers before leaving the plant stack at 147 oC (300 oF). Operating parameters are summarized in Table 8-19. Cycle performance is summarized in Table 8-20. The overall net electric LHV efficiency is 80.1 percent. One advantage of this concept is the elimination of heat exchangers between fuel cell modules. This will minimize the cycle complexity, cost, and losses. Another advantage of the concept is the minimization of unreacted fuel leaving the fuel cell. By having discrete fuel cell stages, each operating with its own voltage and current density, fuel utilization can be pushed to very high levels without hurting the performance of the entire module. The voltage and performance degradation resulting from the low fuel concentrations (high utilization) is isolated to the latter fuel cell stage(s) whereas a single fuel cell module, the entire fuel cell performance is degraded. Experiencing a reduced voltage, power, and efficiency level in the latter stages of a multi-stage module is acceptable because it minimizes the heat released in the combustion stage, which is largely passed to the bottoming cycle, which typically has an efficiency of roughly 40 percent. That is, 60 percent of the heat liberated to the bottoming cycle is wasted. Thus, the minimization 51. A "mild reformer" is assumedto eliminate of the higher hydrocarbons prior to entering the fuel cell to prevent sooting. This reformer is called a "mild reformer" to indicate that the reforming reactions are not pushed to completion, for it is desired that the methane be reformed in the fuel cell for better temperature management. Some of the methane, however, will be reformed with the higher hydrocarbons in the mild reformer. 8-64PDF Image | Fuel Cell Handbook (Seventh Edition)
PDF Search Title:
Fuel Cell Handbook (Seventh Edition)Original File Name Searched:
fuel-cell-handbook.pdfDIY PDF Search: Google It | Yahoo | Bing
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
IT XR Project Redstone NFT Available for Sale: NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Be part of the future with this NFT. Can be bought and sold but only one design NFT exists. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Turbine IT XR Project Redstone Design: NFT for sale... NFT for high tech turbine design with one part 3D printed counter-rotating energy turbine. Includes all rights to this turbine design, including license for Fluid Handling Block I and II for the turbine assembly and housing. The NFT includes the blueprints (cad/cam), revenue streams, and all future development of the IT XR Project Redstone... More Info
Infinity Turbine ROT Radial Outflow Turbine 24 Design and Worldwide Rights: NFT for sale... NFT for the ROT 24 energy turbine. Be part of the future with this NFT. This design can be bought and sold but only one design NFT exists. You may manufacture the unit, or get the revenues from its sale from Infinity Turbine. Royalties go to the developer (Infinity) to keep enhancing design and applications... More Info
Infinity Supercritical CO2 10 Liter Extractor Design and Worldwide Rights: The Infinity Supercritical 10L CO2 extractor is for botanical oil extraction, which is rich in terpenes and can produce shelf ready full spectrum oil. With over 5 years of development, this industry leader mature extractor machine has been sold since 2015 and is part of many profitable businesses. The process can also be used for electrowinning, e-waste recycling, and lithium battery recycling, gold mining electronic wastes, precious metals. CO2 can also be used in a reverse fuel cell with nafion to make a gas-to-liquids fuel, such as methanol, ethanol and butanol or ethylene. Supercritical CO2 has also been used for treating nafion to make it more effective catalyst. This NFT is for the purchase of worldwide rights which includes the design. More Info
NFT (Non Fungible Token): Buy our tech, design, development or system NFT and become part of our tech NFT network... More Info
Infinity Turbine Products: Special for this month, any plans are $10,000 for complete Cad/Cam blueprints. License is for one build. Try before you buy a production license. May pay by Bitcoin or other Crypto. Products Page... More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)