Thermochemical heat storage technology is a key research and development direction in the field of heat storage at home and abroad

on January 3 this year,Beijing Thermal Power's Third Generation Thermal Storage Technology Research and Demonstration Technology Development Service Procurement Project Based on Thermochemical Heat StorageThe results of the winning bid were announced,University of Science and Technology BeijingThe bid was awarded at a bid price of 1.85 million yuan. it has been learned that,Beijing University of TechnologyandBeijing Tianyo Jingcheng Electromechanical Equipment Co., Ltd.Many other units also participated in the project bidding.

Thermal chemical heat storage technology refers to a technology that uses the storage and release of heat in the process of chemical change to achieve the purpose of thermal energy storage,It can realize seasonal storage and long-distance transportation of thermal energy, and has great application value in the utilization of industrial waste heat, solar thermal storage and chemical heat pump, which is regarded as the key direction of the future development of heat storage technology..

However, the thermal chemical heat storage technology is difficult to control the heat storage process, there are problems in the matching of chemical reaction and heat transfer, and the stability needs to be further tested. Compared with the sensible heat storage and phase change heat storage that have been commercialized, the thermal chemical heat storage technology is mostly in the laboratory verification stage.At present, relevant research institutions in many countries, including China and the United States, are carrying out relevant research.

It is understood that the above-mentioned Beijing thermodynamic and chemical heat storage technology research project is a key scientific and technological project. The project focuses on three key scientific and technical issues of the third generation heat storage technology based on thermochemical heat storage: heat production and heat storage based on thermochemical heat storage technology; Flow and heat transfer of medium and low temperature unsteady reaction system and heat transfer enhancement of thermochemical heat storage system. The start of this research project will further promote the research and development of thermochemical heat storage technology in China.

In addition, many domestic universities such as Shanghai Jiaotong University have studied many key issues such as thermochemical reaction kinetics, and have obtained many experimental experiences and research results.

In foreign countries, many institutions have done a lot of research on the performance optimization of the reactant system of the thermochemical energy storage system, the design of the energy storage system, the enhanced heat and mass transfer of the reaction bed, and the performance of the cycle, and many thermochemical energy storage experimental prototypes have been established.

In general, the thermochemical energy storage system mainly includes redox system, metal hydride system, carbonate decomposition system, ammonia decomposition system, methane reforming system and inorganic hydroxide system. Among them, the typical gas-solid reaction system Ca(OH)_2/CaO is considered to be one of the most potential high-temperature thermal chemical energy storage systems because of its cheap raw materials, environmental friendliness and high heat storage capacity.

In May 2016, researchers at Oregon State University and the University of Florida collaborated to launch a new type of thermochemical energy storage system that can be used to store and release solar energy. Compared with traditional heat storage equipment, the improved energy storage scheme of American researchers adds a thermochemical energy storage system similar to batteries,During the "charging" period of the system, the strontium carbonate decomposes into strontium oxide and carbon dioxide under the action of solar thermal energy.When "discharged", strontium oxide and carbon dioxide are synthesized, releasing the stored heat.The materials for the energy storage system are readily available, non-flammable and environmentally friendly, and the compounds synthesized using these materials operate at temperatures up to 1200 degrees Celsius,Thermal storage efficiency is two times higher than existing thermal storage systems.

In Sweden,SaltX TechnologiesIt has been in the forefront in promoting the commercial application of thermochemical heat storage technology. Sweden's SaltX technology company was founded in 2001.New Salt Crystal Energy Storage TechnologyThe main use of salt crystals and their solutions at different temperatures, chemical reactions to store and release energy, can be applied to the field of solar thermal power generation, solar refrigeration and air conditioning, so that energy consumption and energy storage costs reduced by about 33%. At present, the company has established cooperative relationships with companies such as General Electric, Ruimei Manufacturing and Alfa Laval, and provides new energy storage solutions.

Generally speaking, the temperature range of thermochemical heat storage is high and the heat storage density is large, but the process is complex and the technical maturity is low, and a good match between reaction rate and heat transfer performance is needed, which is worthy of further study,With the gradual solution of the problem, its application prospects will be very broad..