State Power Investment Corporation Research Institute, Future Science Park, Beijing, 102209, China

---

Abstract: Owing to a passive containment cooling system (PCCS) design in the AP/CAP series nuclear power plants, the containment can be cooled within 72 h after the accident using a passive containment cooling water storage tank (PCCWST). However, after 72 h, if the top tank is not able to replenish water in time, it is difficult to take all of the waste heat away by the containment itself; thus, the containment is still prone to overpressure risk. Aiming at the shortboard with a limited time of exporting the waste heat of the containment in a nuclear power plant, this paper studied in-depth a set of innovative passive heat removal system for the containment. In addition, an experimental system was set up to study the thermal performance of the system at different pressures, temperatures, and gas compositions under the condition of design basis accident. The results show that the heat capacity of the system completely meets the design requirements.

---