China Huaneng said on 16 August that testing of the steam turbine using non-nuclear steam had been completed at the demonstration high-temperature gas-cooled reactor plant (HTR-PM) at Shidaowan, in Shandong province. The two-unit HTR-PM is scheduled to begin operations later this year. The HTR-PM comprises two small reactors that will drive a single 210 MWe turbine. Helium gas is used as the primary circuit coolant.
China Huaneng is the lead organisation in the consortium building the units (with a 47.5% stake), together with China National Nuclear Corporation subsidiary China Nuclear Engineering Corporation (CNEC) (32.5%) and Tsinghua University's Institute of Nuclear and New Energy Technology (20%), which is the research and development leader. Chinergy, a joint venture of Tsinghua and CNEC, is the main contractor for the nuclear island.
China Huaneng said the expected value of the parameters met the design requirements and the system is stable. The steam turbine test follows a "dual-cooling and dual-heating joint debugging" test of the nuclear island.
Non-nuclear steam is used at nuclear power projects to check the operating quality of steam turbine units and conventional island systems in advance of start-up. It is mainly used to verify the design, manufacture, and production of steam turbine units; to check installation quality; and to test the joint operation ability of the conventional island water, steam, oil, and gas auxiliary systems. It prepares the way for the next step in which "nuclear steam" is used and the unit is connected to the grid.
In a high-temperature gas-cooled reactor NPP, the unique air-cooling" technology and the structural characteristics of the steam generator means non-nuclear flushing cannot be undertaken using a pressurised water reactor test method. In response to this problem, Huaneng Shidaowan Nuclear Power Company collaborated with Huaneng Nuclear Energy Institute, Xi’an Thermal Engineering Institute, National Nuclear Institute, Shanghai Turbine Plant, Beijing Guangli Nuclear, Tsinghua University Nuclear Research Institute, China Nuclear Energy, Huaneng Shanghai Maintenance Company and other units, to find a way to optimise the configuration of existing system equipment. The result was development and commissioning of new non-nuclear impulse test equipment - the start-up superheater.
During testing using this new equipment, more than 50 defects were found and resolved, and the conventional island was fully inspected. This test not only further trained Huaneng's nuclear power production and technical personnel, but also laid the foundation for the demonstration project to be connected to the grid this year,
China Huaneng noted.
China has been developing high temperature gas-cooled reactor (HTGR) technologies for more than 40 years, mainly at the Institute of Nuclear and New Energy Technology (INET) of Tsinghua University in Beijing. Since the late 1980s, the National High-tech R&D Programme has designed, constructed, commissioned and operated a 10MW thermal power test reactor (HTR-10).
Based on the HTR-10 achievements, INET began development of a commercial nuclear power plant comprising modular HTGRs. The demonstration HTR-PM project was launched in 2001 and construction of the plant began in December 2012. A further 18 HTR-PM units are planned for the Shidaowan site.
Cold functional tests were completed at the HTR-PM's two reactors in October and November 2020 using Hot functional tests began in January to simulate the thermal working conditions of the plant and verify that nuclear island and conventional equipment and systems meet design requirements.
China is also planning a larger HTGR. The HTR-PM600 will have a 650 MWe turbine driven by some six HTR-PM reactor units. Feasibility studies on HTR-PM600 deployment are under way for Sanmen, Zhejiang province; Ruijin, Jiangxi province; Xiapu and Wan'an, in Fujian province; and Bai'an, Guangdong province.