HTTR-GT/H2 test plant - conceptual design study on new intermediate heat exchanger - 18747

Japan Atomic Energy Agency is developing a nuclear cogeneration demonstration test facility named HTTR-GT/H2 that is connected to the existing test reactor HTTR. In the facility, an intermediate heat exchanger (IHX) at maximum service temperature of 900 deg. C is to be newly constructed to supply the high temperature helium flows to both the helium gas turbine system and the hydrogen production system. The conceptual design study on the IHX is conducted considering the future application to the Gas Turbine High Temperature Reactor 300 Cogeneration (GTHTR300C). Several new concepts are proposed and incorporated in the demonstrating IHX design in order to (1) ease integration of the IHX with the gas turbine system to simplify the cogeneration plant layout; (2) allow conventional low-cost steel for construction of the IHX pressure vessel and nozzles; (3) flexibility to accommodate thermal expansion of the bundle and internal structures.; (4) maintaining the structural integrity at elevated service temperature range. This paper describes the conceptual design study results for the IHX and technical issues to be solved in the future design phases. (authors)