基于高温熔盐储热的火电机组灵活性改造技术及其应用前景分析

  目的  在分析常规火电机组灵活性改造方案存在问题的基础上，提出了一种新型的灵活性改造技术方案，即在传统的“锅炉-汽机”热力系统中嵌入大容量高温熔盐储热系统，削弱原本刚性联系的“炉机耦合”，实现火电机组深度调峰和灵活运行。  方法  根据汽、水和熔盐的不同热力特性，利用热力平衡原理，建立了“锅炉-高温储热-汽机”一体化热力系统。  结果  研究表明:火电机组进行高温熔盐储热改造，将极大地提高其深度调峰能力，且能解决常规改造方案存在的问题；同时，机组改造后对外提供高参数工业供汽的能力将得到大幅度提高，这将有效提高电厂经济效益，弥补调峰补偿机制的不足；高温熔盐储热技术也可以应用于火电机组延寿改造，不仅增加系统灵活调峰电源，还可以使老旧电厂企业资产继续发挥效益。  结论  在系统中选择一批火电机组进行大规模高温储热技术改造，可以在不增加煤炭总消费量的基础上，为系统提供大量灵活调峰电源，有效缓解新能源电力消纳问题；同时汽轮发电机组的容量被保留，可为电力系统提供备用容量和转动惯量，保障电力供应和系统安全稳定。该技术的推广，将有力促进火电厂转型升级，助力实现“碳达峰、碳中和”目标。

Flexible Modification Technology and Application Prospect of Thermal Power Unit Based on High Temperature Molten Salt Heat Storage

  Introduction  Through the analysis of the exsiting problems in conventional flexibility modification technology of thermal power units， a new type of flexibility modification technology is proposed， which is to embed a large-capacity high-temperature molten salt heat storage system in the traditional "boiler-turbine" thermal system. It weakens the original rigid connection of boiler-turbine coupling to achieve deep peak regulation and flexible operation of thermal power units.  Method  According to the different thermal characteristics of steam， water and molten salt， an integrated thermal system of "boiler-high temperature heat storage-steam engine" was established by thermal balance calculation.  Result  The results show that the deep peak regulation capability of thermal power unit is greatly improved after configuring high-temperature molten salt heat storage system， and the problems of conventional modification methods can be solved. At the same time， the ability of the units to provide high-parameter industrial steam will be greatly improved. This will effectively improve the economic efficiency of power plants and make up for the lack of peak regulation compensation mechanism. High-temperature molten salt heat storage technology can also be applied to the life extension of thermal power plants， not only increasing the grid's flexible peak regulation power supply， but also enabling old power plant enterprise assets continue to create benefits.  Conclusion  After a batch of thermal power units in the grid are modified by large-scale high-temperature molten salt heat storage technology， a large number of flexible peak regulation power sources are provided for the grid， without increasing the total coal consumption and effectively alleviating the problem of new energy power consumption. Meanwhile， steam turbines and generators are reserved， which can provide backup capacity and moment of inertia for the power system， to ensure the safety and stability of the power supply and the grid. The promotion of this technology will effectively promote the upgrading of thermal power plants and help achieve the goal of "carbon neutrality and carbon peak".