Review of conceptual design and fundamental research of molten salt reactors in China

TLDR

Molten salt reactors are a leading Generation IV nuclear option in China, prized for their superior fuel cycle and thorium utilization. China aims to advance MSR development by focusing on materials, online fuel processing, Th‑U fuel cycle, component design, and thermal‑hydraulic experiments. Researchers have studied both liquid‑fuel and solid‑fuel MSR concepts, performed extensive neutronics, thermal‑hydraulics, safety, and materials modeling, developed COUPLE and FANCY software, built experimental facilities such as a high‑temperature fluoride salt loop, and designed passive residual heat removal systems with a test facility underway. Key MSR technologies—molten‑salt extraction and separation, and N‑base alloy fabrication—have been mastered, enabling the Chinese Academy of Sciences to complete thorium‑based MSR designs for both solid and liquid fuel and to promote their near‑future construction.

Abstract

Molten salt reactor (MSR) as 1 candidate of the generation IV advanced nuclear power systems attracted more attention in China due to its top ranked in fuel cycle and thorium utilization. Two types of MSR concepts were studied and developed in parallel, namely the MSR with liquid fuel and that with solid fuel. Abundant fundamental research including the neutronics modeling, thermal-hydraulics modeling, safety analysis, material investigation, molten salts technologies etc. were carried out. Some analysis software such as COUPLE and FANCY were developed. Several experimental facilities like high-temperature fluoride salt experiment loop have been constructed. Some passive residual heat removal systems were designed, and 1 test facility is under construction. The key MSR techniques including the extraction and separation of molten salt and construction of N-base alloy have been mastered. Based on these fundamental research, Chinese Academy of Sciences has completed the design of thorium-based MSRs with solid fuel and liquid fuel and is promoting their construction in the near future. In China, future efforts should be paid to the material, online fuel processing, Th-U fuel cycle, component design, and construction and thermal-hydraulic experiments for MSR, which are rather challenging nowadays.