Cryogenic Heat Exchanger Insulation for Oxygen Ignition Risk
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cryogenic gas separation units face challenges with complex and costly thermal insulation structures, risk of cryogenic liquid leaks causing material rupture, and potential ignition due to high-pressure oxygen flow in aluminum alloy heat exchangers.
Innovation Solution
A heat exchanger design featuring a partially or fully incombustible thermal insulation layer, such as refractory ceramic fibers, integrated into the envelope, which covers the plates and reduces the need for external insulation, combined with a combustible polyurethane layer for the hot parts, and mechanical fastening for quick assembly, along with thermally insulating suspension members for safe handling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If a metal framework with double wall and bulk insulating material is used for thermal insulation, then thermal insulation is provided, but the structure becomes complex and expensive with long manufacturing and assembly time
Solution Approach 1:
The patent combines the thermal insulation function directly with the heat exchanger structure by integrating an insulating layer onto the plates themselves, rather than using a separate external insulation structure. This merging eliminates the need for complex metal frameworks and double walls, reducing both device complexity and assembly time while maintaining effective thermal insulation.
Solution Approach 2:
The thermal insulation layer is pre-installed on the heat exchanger plates during manufacturing before delivery to the installation site. This preliminary action eliminates the need for on-site assembly of complex insulation structures, reducing installation time and complexity while ensuring proper insulation from the start.
2Power
If aluminum alloy heat exchanger is used, then heat transfer efficiency is improved, but the risk of direct ignition increases under high-pressure oxygen flow
Solution Approach 1:
The patent employs a composite structure where aluminum alloy plates are combined with an incombustible thermal insulation layer. This composite material approach maintains the high heat transfer efficiency of aluminum alloy while the incombustible insulation layer provides a protective barrier that prevents direct ignition under high-pressure oxygen conditions, thus resolving the contradiction between efficiency and safety.
Solution Approach 2:
The incombustible thermal insulation layer acts as an intermediary between the aluminum alloy heat exchanger plates and the high-pressure oxygen environment. This intermediate layer prevents direct contact between the aluminum and oxygen, eliminating the ignition risk while allowing the aluminum plates to continue functioning efficiently for heat transfer.
3Strength
If non-resilient steel is used for frame supporting elements, then structural strength is provided, but rupture occurs when cryogenic liquid leaks reach the supporting elements
Solution Approach 1:
The patent changes the material parameter of the supporting elements from non-resilient steel to resilient material that can withstand cryogenic temperatures. This parameter change allows the supporting elements to maintain structural strength while becoming resistant to rupture when exposed to cryogenic liquid leaks, thus resolving the contradiction between strength and reliability in cryogenic conditions.
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 solution enhances safety by preventing ignition, reduces installation time and costs by pre-installing thermal insulation, and ensures efficient heat transfer while balancing the weight of the heat exchanger during operation.
Implementation Method 1
the envelope comprising at least one so-called incombustible thermal insulation layer which is substantially incombustible under the temperature conditions and oxygen pressure when the heat exchanger is in operation
Implementation Method 2
the incombustible thermal insulation layer limits or even avoids the risk of ignition in the presence of oxygen
Implementation Method 3
heat transfer from at least one primary fluid called calorigenic fluid to at least one secondary fluid called refrigerant
Implementation Method 4
the incombustible thermal insulation layer is formed of refractory ceramic fibers. Thus, such refractory ceramic fibers form an effective thermal insulation for the heat exchanger
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention relates to a heat exchanger (1) comprising: parallel plates (2) defining channels for heating or cooling fluids, spacers extending between the plates (2) and defining channels, and an individual casing covering the plates (2) and comprising a fireproof heat insulation layer.