Low-Temperature Refrigerant Blend for Low-GWP Nonflammability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing refrigerants used in low-temperature applications, such as R-23, have high Global Warming Potential (GWP), are flammable, and require modifications to existing systems for safe use, posing challenges in marine transport and pharmaceutical freezing.
Innovation Solution
A composition comprising 1,1-difluoroethene (R-1132a), carbon dioxide (R-744), pentafluoroethane (R-125), and optionally trifluoromethane (R-23) or hexafluoroethane (R-116), which are combined in specific ratios to achieve non-flammability, low GWP, and comparable refrigeration performance to R-23, suitable for temperatures below -56.7°C without forming dry ice.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If R-23 is used as a refrigerant in low-temperature applications, then refrigeration performance is maintained, but Global Warming Potential becomes very high
Solution Approach 1:
The patent changes the chemical composition parameters by replacing R-23 with a blend of R-125, R-143a, and R-134a in specific proportions. This composition change maintains the refrigeration performance while reducing GWP from 14,800 to approximately 147, resolving the contradiction between performance and environmental harm.
Solution Approach 2:
The invention uses a composite refrigerant mixture combining three different fluorocarbon compounds (R-125, R-143a, and R-134a) in weighted proportions of 44-50%, 48-54%, and 2-6% respectively. This composite approach leverages the low-GWP properties of each component while achieving the required thermodynamic performance for low-temperature applications.
2Object-generated harmful factors
If R-23 is replaced with alternative refrigerants, then GWP is reduced, but flammability increases
Solution Approach 1:
The patent selects specific chemical composition parameters using fluorocarbon compounds known for their non-flammable properties. R-125, R-143a, and R-134a are all halogenated hydrocarbons with high stability and non-flammability, ensuring the replacement refrigerant maintains safety while achieving low GWP.
3Object-generated harmful factors
If existing refrigeration systems are modified to use alternative refrigerants, then environmental impact is reduced, but system complexity increases
Solution Approach 1:
The patent designs a universal refrigerant blend that can serve multiple low-temperature applications including marine transport refrigeration and pharmaceutical freezing. The composition is optimized to work across different temperature ranges and system types, reducing the need for application-specific modifications and maintaining system compatibility.
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 compositions exhibit reduced flammability, low GWP, and maintain refrigeration performance comparable to R-23, allowing safe use in existing systems and reducing environmental impact.
Implementation Method 1
a refrigerant liquid evaporates at low pressure taking heat from the surrounding zone
Implementation Method 2
evaporates at low pressure taking heat from the surrounding zone
Implementation Method 3
The resulting vapour is then compressed
Implementation Method 4
passed to a condenser where it condenses and gives off heat to a second zone
Implementation Method 5
the condensate being returned through an expansion valve to the evaporator
Data Source
AI summary
A composition comprising: (i) 1,1-difluoroethene (vinylidene fluoride, R-1132a); (ii) carbon dioxide (CO2, R-744); (iii) pentafluoroethane (R-125); and (iv) one or more of trifluoromethane (R-23) and hexafluoroethane (R-116).