Performance and optimization of an HTR cogeneration system

This paper assesses performance of a high temperature reactor (HTR) coupled with a Rankine cycle cogeneration plant which simultaneously produces moderate temperature steam and electricity for a process heat application. Understanding the trade-offs of configurations on the performance and complexity of an HTR cogeneration application will help further HTR commercialization. Results indicate that the trade-off between process steam and electricity production is nearly linear. For a 300 degrees C process steam production temperature every 1 kg/s increase in steam production leads to a 1 MWe reduction in electricity production. For pure electricity production an acceptable cycle efficiency of 46% is achieved. When steam-to-steam reheat is added, cycle efficiency marginally improves to 46.2%, but low pressure turbine exhaust quality dramatically improves from 78% to 95%. The application of an HTR for a cogeneration plant appears feasible, but a more detailed extension of this analysis is required. Future work should include a more complete cogeneration plant with additional feedwater heaters, moisture separators, and high pressure and low pressure reboilers. (C) 2011 Elsevier B.V. All rights reserved.