Liquefied Hydrogen Loading Arm with Piggyback Purging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional LNG loading arms are not suitable for liquefied hydrogen due to the need for swivel joints with high thermal insulation, which are complex and costly, and require gas replacement with expensive gases like hydrogen or helium for purging, making efficient transportation challenging.
Innovation Solution
A liquefied hydrogen loading arm with a support frame structure and flexible vacuum insulation double tubes, eliminating the need for swivel joints and using piggyback lines for efficient gas replacement with hydrogen, reducing facility costs and operation time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional LNG loading arm structure with swivel joints is used for liquefied hydrogen, then the loading arm can be assembled with standard components, but the thermal insulation performance is insufficient and facility cost increases due to need for special insulated swivel joints
Solution Approach 1:
The patent removes the swivel joint component from the loading arm structure entirely. Instead of using a swivel joint that would require complex insulation, the system employs a flexible vacuum insulation double tube that can bend and rotate without mechanical joints, extracting the problematic component while maintaining functionality.
Solution Approach 2:
The patent uses a composite structure consisting of an inner tube, outer tube, and vacuum insulation layer. This composite design provides both the necessary flexibility for movement and superior thermal insulation performance, replacing the need for insulated mechanical swivel joints.
2Temperature
If flexible vacuum insulation double tube is used in the loading arm, then thermal insulation performance is improved, but the tube length must be increased and support structure becomes complex
Solution Approach 1:
The patent employs a flexible vacuum insulation double tube with corrugated structure that can bend and deform without rigid supports. The flexibility of the thin-walled corrugated tube eliminates the need for complex support structures while maintaining the vacuum insulation integrity throughout the tube's range of motion.
Solution Approach 2:
The loading arm system is designed to be dynamic rather than static, allowing the flexible tube to naturally accommodate movements through its inherent flexibility. The tube's corrugated structure enables it to flex and extend as needed without requiring active support mechanisms, reducing overall system complexity.
3Reliability
If gas replacement is performed in the vacuum insulation double tube, then hydrogen purity is maintained, but the process takes much longer due to annular corrugations in the inner tube
Solution Approach 1:
The patent extracts the gas replacement process from the vacuum insulation double tube itself and relocates it to a separate piggyback line. This allows the main hydrogen transport tube to maintain its vacuum insulation and hydrogen purity without undergoing time-consuming gas replacement operations.
Solution Approach 2:
The piggyback line serves as an intermediary channel for gas replacement operations. It runs parallel to the vacuum insulation double tube and provides a separate pathway for introducing hydrogen or performing maintenance operations, eliminating the need to disrupt the main hydrogen transport system.
4Reliability
If inactive gas is used for purging in the loading arm, then safety is improved by preventing evaporation, but the cost increases due to use of expensive hydrogen or helium gas
Solution Approach 1:
The system uses itself to provide the purging function. During normal hydrogen loading operations, the hydrogen flow itself serves to purge the system of air and inactive gases. The continuous flow of hydrogen through the loading arm naturally displaces any residual gases, eliminating the need for separate expensive purging operations.
Solution Approach 2:
The system recovers and reuses hydrogen that would otherwise be discarded during purging operations. By performing gas replacement through the piggyback line rather than the main tube, the hydrogen in the vacuum insulation double tube is preserved and can continue to be used, reducing overall hydrogen consumption.
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 enables efficient gas replacement and transportation of liquefied hydrogen with reduced costs and operational time, maintaining high purity of hydrogen by avoiding contact with air and inactive gases.
Implementation Method 1
a flexible vacuum insulation double tube including an inner tube, an outer tube, and a vacuum insulation layer
Data Source
AI summary
A liquefied hydrogen transport method includes connecting first and second loading arms to the manifold while vacuum insulation double tubes of the first and second loading arms are filled with hydrogen gas and air is mixed in piggyback lines; supplying an inactive gas to one of the piggyback lines of the first and second loading arms and taking in a gas mixture of an inactive gas and air from the other of the piggyback lines of the first and second loading arms; supplying hydrogen gas to one of the piggyback lines of the first and second loading arms and taking in a gas mixture of hydrogen gas and an inactive gas from the other of the piggyback lines of the first and second lading arms; and transporting liquefied hydrogen through any one of the vacuum insulation double tubes of the first and second loading arms.