Method and system of high-temperature calcium looping thermochemical energy storage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current solar thermal power generation faces challenges with intermittency, low energy density, instability, and unsustainable supply, particularly in efficiently and effectively storing solar energy for continuous power generation.
Innovation Solution
A high-temperature calcium looping thermochemical energy storage system utilizing a CaCO3/CaO system, where solar energy heats CaCO3 particulates to decompose into CaO and CO2, storing energy chemically, and reversing the reaction to release heat when needed, using a bidirectional high-temperature vibrating fluidized bed reactor and CO2 as a heat exchange, fluidization, and reaction medium.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If solar thermal power generation is used, then clean energy production is achieved, but intermittency and instability problems occur
Solution Approach 1:
The system performs preliminary action by storing solar energy in chemical form (CaCO3) during periods of high solar availability. The calcium looping thermochemical energy storage system captures solar thermal energy and stores it as chemical potential energy in calcium carbonate, which can be later converted back to thermal energy and electricity when solar input is insufficient, thereby resolving the intermittency and reliability issues while maintaining clean energy production.
2Quantity of substance
If thermochemical energy storage is implemented, then energy storage density is improved, but system complexity increases
Solution Approach 1:
The calcium looping system employs self-service principles where the same CaO/CaCO3 material cycle serves multiple functions: heat storage, heat transfer, and chemical energy storage. The system uses the exothermic carbonation reaction of CaO with CO2 to simultaneously store energy and transfer heat, eliminating the need for separate heat storage and transfer systems, thus achieving high energy density without proportionally increasing system complexity.
3Use of energy by moving object
If high-temperature reaction is used for energy storage, then energy storage efficiency is improved, but material durability decreases
Solution Approach 1:
The system applies parameter changes by carefully controlling reaction temperature, pressure, and gas composition to optimize both energy storage efficiency and material durability. By maintaining reactions within specific temperature ranges and using appropriate partial pressures of CO2, the system achieves high energy storage efficiency while minimizing thermal stress and chemical degradation of the calcium looping materials, thereby extending their operational lifespan.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This system achieves high energy storage density, efficient energy conversion, and sustainable power supply by transforming thermal energy into chemical energy and back, enhancing the stability and efficiency of solar thermal power generation.
Implementation Method 1
a solar energy absorption tower, configured for absorbing solar energy
Implementation Method 2
CaCO3 solid particulates are indirectly heated by hot air generated from solar energy to perform an endothermic decomposition reaction
Implementation Method 3
perform an endothermic decomposition reaction, and received heat is stored in decomposition products of CaO and CO2 in a form of chemical energy
Implementation Method 4
a reversible thermochemical reaction between the CaO and the CO2 occurs under atmospheric pressure, and the chemical energy stored in the CaO and the CO2 is reversely converted into the heat for release
Implementation Method 5
the reactor is preferably a bidirectional high-temperature vibrating fluidized bed reactor
Implementation Method 6
a bidirectional high-temperature vibrating fluidized bed reactor, which has a function of promoting sufficient fluidization of solid particulates
Implementation Method 7
The CO2 is preheated in the powder heat exchanger C by using the waste heat of the synthetic product CaCO3 solid particulates
Implementation Method 8
reaction waste heat of the product CO2 generated by decomposing the CaCO3 solid particulates is configured to preheat subsequently reacted CaCO3 solid particulates in the powder heat exchanger B
Data Source
AI summary
A method and a system of a high-temperature calcium looping thermochemical energy storage are provided. A thermochemical energy storage system is based on CaCO3/CaO, and an energy storage is performed by a mutual transformation between a thermal energy and a chemical energy. When solar irradiation is sufficient, CaCO3 solid particulates are indirectly heated by hot air generated from solar energy to perform an endothermic decomposition reaction, and received heat is stored in decomposition products of CaO and CO2 in a form of the chemical energy. When heat is required, a reversible thermochemical reaction occurs between the CaO and CO2 under an atmospheric pressure, and the chemical energy stored in the CaO and CO2 is transformed into the heat for release.