Industrial Hydrated Salt Thermal Storage via DSC-Guided Water Adjustment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing recrystallization method for industrial grade bischofite does not sufficiently enhance its latent heat storage capacity, resulting in lower phase change latent heat compared to analytical and superior purity MgCl2·6H2O due to residual intercrystalline brine.
Innovation Solution
A method combining differential scanning calorimeter (DSC) testing and stepping evaporation or dilution to adjust the water content of industrial grade hydrated salts, iteratively refining the mass and melting enthalpy until it matches that of superior purity salts, thereby improving thermal energy storage performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional recrystallization method is used to process industrial grade bischofite, then the latent heat storage performance is improved, but the latent heat of phase change remains lower than analytical purity hydrated salt due to residual intercrystalline brine
Solution Approach 1:
The patent applies parameter changes by precisely controlling the water content of industrial grade hydrated salts within the range of 105-130% of the theoretical water content (m0), and adjusting the mass of the aqueous system during stepwise evaporation or dilution. This parameter control enables the melting enthalpy to reach within -5 to 5 J/g of superior purity hydrated salt, resolving the contradiction between maintaining industrial grade processing and achieving high latent heat storage performance.
Solution Approach 2:
The patent employs dynamic adjustment through stepwise evaporation or dilution processes, where the mass of the aqueous system is adjusted in increments of 0.4-0.8% m0 at each step. The process continues iteratively until the melting enthalpy difference between samples satisfies the criterion ΔH2n>ΔHn+1 or falls within -5 to 5 J/g of the reference value. This dynamic approach allows the system to adaptively optimize the water content and melting enthalpy, achieving high latent heat storage performance while maintaining industrial grade processing.
2Use of energy by moving object
If water content is increased to 105-130% of theoretical value, then the melting enthalpy can be enhanced, but the mass control and processing complexity increase
Solution Approach 1:
The patent segments the processing into distinct steps: Step S1 involves heating the aqueous system to a specific mass range (105-130% m0) and performing initial DSC testing; Step S2 involves stepwise evaporation or dilution with mass adjustments of 0.4-0.8% m0 per step and iterative DSC testing. This segmentation transforms a complex optimization problem into manageable discrete steps, reducing processing complexity while achieving high melting enthalpy.
Solution Approach 2:
The patent implements feedback control through iterative DSC testing at each step of the process. The melting enthalpy measurements from DSC testing provide feedback that guides whether to continue evaporation or dilution, and determines when the optimal water content and melting enthalpy have been achieved. This feedback mechanism automates the optimization process, reducing the need for complex manual control while ensuring high melting enthalpy performance.
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
The method enhances the latent heat storage capacity of industrial grade hydrated salts to a level comparable to superior purity, despite higher impurity levels, by precisely regulating the water content through DSC-guided evaporation and dilution processes.
Implementation Method 1
heating an aqueous system of industrial grade hydrated salts containing industrial grade hydrated salt of 105-130% of m0 by mass, and taking a sample No. 1 from the system for differential scanning calorimeter (DSC) testing
Implementation Method 2
heating the aqueous system... and taking a sample No. 1 from the system for differential scanning calorimeter (DSC) testing when the mass of the aqueous system of industrial grade hydrated salts is reduced to m0
Implementation Method 3
Method for enhancing thermal energy storage performance of industrial grade hydrated salts based on phase change
Implementation Method 4
recording a melting enthalpy of sample No. 1 as ΔH1
Data Source
AI summary
Disclosed is a method for enhancing thermal energy storage performance of industrial grade hydrated salts based on phase change, comprising: heating an aqueous system of industrial grade hydrated salts containing 105-130 percent (%) by mass of m0 industrial grade hydrated salt to m0, taking a sample for differential scanning calorimeter testing and recording its melting enthalpy as ΔH1; melting and adding water into, or melting and evaporating the residual aqueous system of industrial grade hydrated salts or the residual industrial grade hydrated salts system with a mass of m1 to increase or decrease the mass by 0.4-0.8% m0 until a melting enthalpy ΔHn of a sample that taken from the residual aqueous system of industrial grade hydrated salts with a mass of mn satisfies ΔH2< . . . <ΔHn>ΔHn+1.