Design and Performance Evaluation of a Tri-Generation System for Hydrogen, Power and Heat Production Based on Solid Oxide Fuel and Electrolysis Cells
| Autor: | Chi-Ting Lin, 林麒庭 |
|---|---|
| Rok vydání: | 2018 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 106 The solid oxide cells (SOCs) is one of the most important technologies for alternative energy. That are able to operate in two modes: solid oxide fuel cell (SOFC) and solid oxide electrolysis cell (SOEC). SOFC can be used for combined heat and power (CHP) applications because of its high operating temperature. SOEC consumes electricity and heat to produce hydrogen via a steam electrolysis reaction. Operation of SOEC in high temperature by providing an external heat source improves SOEC performance and reduces its electricity requirement. The partial oxidation reaction (POX), which is a highly exothermic reaction, can be used as an external heat source and can produce fuel from natural gas for SOFC. This study innovatively combines POX with SOFC and SOEC to design a tri-generation system for the production of heat, hydrogen and power. The system is simulated using AspenPlus. The effects of several important operational variables on the system, including the SOFC fuel utilization, the operating temperature of three units, and SOEC steam utilization are analyzed. The comparisons of various configurations between a conventional SOFC and a SOFC integrated with the POX reaction system (POX-SOFC), conventional SOEC and a SOEC integrated with the POX reaction system (POX-SOEC), conventional SOFC-SOEC and a SOFC-SOEC integrated with the POX reaction system (POX-SOFC-SOEC) are carried out. To achieve optimal design, this study evaluate system performance in terms of reforming efficiency, cogeneration efficiency and total tri-generation efficiency. This study propose configurations compared with the conventional systems have four advantages: (1) POX-SOFC system improves the net electric efficiency about 53% compared with conventional SOFC system; (2) POX-SOEC system improves the energy efficiency about 7% compared with conventional SOEC system; (3) POX-SOFC-SOEC system improves the net electrical efficiency about 182% compared with conventional SOFC-SOEC system under the same conditions and hydrogen efficiency 11%. If combined SOFC cathode gas recycle, the net electrical efficiency can enhance about 199%; (4) The total tri-generation efficiency is POX-SOFC-SOEC system about 97% which can avoid the carbon deposition. This result indicates that the partial oxidation reactor improves system to obtain a high energy efficiency. Therefore, light of novel POX-SOFC-SOEC tri-generation system is a valuable energy technology. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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