Session: 01-04: Nuclear Plant Operation, Modification, Life Extension, Maintenance and Life Cycle - IV

Paper Number: 134681

134681 - Design and Calculation of Nuclear Heating System Utilizing a Molten Salt Heat Storage Circuit for Waste Heat Absorption and Peak Regulation 

Abstract: 

The study focuses on a nuclear heating system that utilizes a nuclear heating reactor as the heat source, and it proposes a low-temperature molten salt heat storage system that is integrated with the nuclear heating system. Molten salt heat storage systems have been widely adopted in thermal power units as peaking modes, significantly enhancing the operational flexibility of such units. By integrating the molten salt heat storage system into the nuclear heating reactor system, molten salt can be utilized to temporarily store excess heat generated by the reactor during periods of low user demand, which can then be released when there is high demand for heat. This approach improves both the peak load capacity and operational flexibility of the nuclear heating system. Additionally, coupling a low-temperature molten salt heat storage system can replace some functions of the original reactor waste heat removal system, absorb the shutdown waste heat at the initial stage of the reactor shutdown, and temporarily store and use it through various ways. This paper aims to evaluate the feasibility of using molten salt as a nuclear heating system integrated with molten salt storage system for peak heating. Based on these findings, preliminary calculations will be conducted to determine the peak load capacity of the molten salt.

The preliminary design of the nuclear heating system for the coupled low-temperature molten salt heat storage system is presented in this paper by conducting relevant investigations on the molten salt heat storage circuit and the nuclear energy heating system. The designed system is based on the three circuits of the integrated nuclear low-temperature heating reactor: the original one, two, and three circuits of the nuclear energy heating system (the reactor primary circuit is situated inside the pressure vessel, while the second circuit serves as an isolation circuit, and finally, the third circuit connects to two-stage thermal users). The primary heat user in this design is the factory that utilizes approximately 200℃ steam, whereas district heating users serve as secondary heat users who act as main peak regulation users. Additionally, there exists a molten salt heat storage system connected to the second circuit of the reactor along with a separate circuit for secondary heat users where both molten salt heat in the molten salt circuit and return water from the primary heat user are utilized by the secondary heat users. By employing programming techniques, a one-dimensional simulation model of this system is established. Based on this model's calculations and analysis, it determines whether it is feasible to use molten salt circuit as the peak regulating and waste heat absorption module in nuclear heating system. Simultaneously, it calculates the peak regulating capacity for secondary heat users in conjunction with the heat released by both molten salt and the backwater of the primary heat user; thereby providing an available interval for peak regulation.

Presenting Author: Haofang Chong Harbin Engineering University

Presenting Author Biography: Currently a Master's student in Nuclear engineering and nuclear technology at Harbin Engineering University. Engaged in nuclear energy heating system-related research work.

Authors:

Haofang Chong Harbin Engineering University
Ruojun Xue Harbin Engineering University
Sen Wang Harbin Engineering University
Yaowu Cao Harbin Engineering University
Furu Jing Harbin Engineering University