光热电站储热系统设计及储罐预热方案研究

Design for CSP plants'energy storage system and research on preheating strategy with tanks

储热系统是光热电站的重要子系统及事故高发系统之一,是光热电站能够持续稳定运行的关键,储热系统的精细化设计对光热电站成本控制及安全稳定运行具有重要意义。提出了光热电站储热系统储罐熔盐量及壁厚的精细化设计方法,通过数值模拟烟气和熔盐在储罐内的流动过程和储罐的实时壁温,获得不超过储罐允许最大壁温差的预热方案,用于减少储罐预热过程中的热应力,降低储罐的风险和故障率。该预热方案在实际项目中应用取得了良好的效果。

As an important and accident-prone subsystem in CSP plants,heat storage system plays a key role in continuous and steady operation of plants.Thus,a delicate design for the storage system is essential for the cost control and safety operation of CSP plants.A delicate design for molten salt volume and wall thickness of tanks in the thermal storage system of CSP plants has been presented.The preheating strategy with the maximum wall temperature difference allowed by storage tanks was obtained after testing the real-time wall temperature of the storage tank and numerically simulating the air flow process of flue gas and molten salt in the tank.The strategy can relieve the thermal stress during storage tank preheating and reduce its risk and failure rate.The strategy has achieved positive effect in practical cases.