Feasibility of an innovative long-life molten chloride-cooled reactor

Abstract

Molten salt-cooled reactor is one of the six Gen-IV reactors with promising characteristics including safety, reliability, proliferation resistance, physical protection, economics, and sustainability. In this paper, a small innovative molten chloride-cooled fast reactor (MCCFR) with 30-year core and a target 120-MWt thermal power was presented. For its feasible study, neutronics, thermal-hydraulics, and radiation damage analysis were performed. The key design properties including kinetics parameters, reactivity swing, reactivity feedback coefficients, maximum accumulated displacement per atom (DPA) of reactor pressure vessel (RPV) and fuel cladding, and maximum coolant, cladding, and fuel temperatures were evaluated. The results showed the MCCFR could operate without refueling for 30 years with overall negative reactivity feedback coefficients up the end of its life. During its 30-year life, the excess reactivity was well managed by constantly pulling out the control rods. The maximum accumulated DPA on RPV and fuel cladding were 8.92 dpa and 197.03 dpa, respectively, which are both below the design limits. Similarly, the maximum coolant, cladding and fuel center temperatures were all below the design limits during its entire lifetime. According to these results, the MCCFR core design with long life is feasible.

Measurements of the 107 Ag neutron capture cross sections with pulse height weighting technique at the CSNS Back-n facility

“…The role of the lead absorber is mainly to shield the in-beam γ background, and it will also have a certain impact on the flux and 038204-2 energy of the neutron beam. Since the response function of the beam line under mode (2) has not been measured completely, all the measurements in this experiment are under mode (1). Our previous work [37] has measured the neutron capture cross section of 197 Au and verified that the experiments and data processing are valid.…”

“…Its main function is to compensate for the remaining reactivity of the initial charge, adjust and maintain the reactor to operate at a specific power and to ensure that the stack can be shut down safely in normal or emergency situations. [1] The control rod absorber is continuously consumed in a high neutron flux environment, which causes the value of the control rod to change with the fuel consumption. In the early days, the safety margin of the reactor was relatively large, the fuel consumption in the reactor was relatively shallow, and the role of the control rod in the operation strategy was not obvious.…”