Thermal coupling of HTGR and desalination system, and performance and cost analysis

Abstract

Water crisis is one of the most serious problems that humans are facing. Desalination technologies are attractive and sustainable solutions for water crisis. Specially, the nuclear desalination based on the HTGR and the MED have been drawing attention, because we can utilize virtually free energy from the HTGR for nuclear desalination. The research objectives are as follows: (a) proposing an optimal design of the HTGR + MED system, (b) safety, performance and cost analysis for the HTGR + MED system, (c) code development for desalination performance and cost analysis.

In the first step, we proposed the KAIST HTGR + MED coupling scheme, which uses the PCHE instead of the conventional heat exchanger without any intermediate loop and has the independent structure between the MED plant and the heat sink. In the second step, the K-DEEP code was developed for more practical cost and performance analysis of the KAIST HTGR+MED system. The desalination performance and cost analysis with the K-DEEP code was performed for the GT-MHR + MED system using the KAIST coupling scheme. The maximum desalted water production capacity increases by 375% compared to the production capacity using the previous coupling scheme. The desalted water cost could be reduced by 5.78%. As a result, we could confirm the potential of the KAIST HTGR+MED system that may be one of the best desalination options in mass production of desalted water. The last step to analyze the effects on reactor safety and performance of HTGRs due to failures or accidents of desalination plants coupled with the HTGRs. From the safety analysis with the GAMMA-T code, we can say that the failure of the MED plant does not lead to any serious safety and performance problems on the KAIST HTGR+MED system.