Hydrogen Gas Production Using Liquid CO₂ Phase Separation Cooling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing hydrogen gas production methods are energy-intensive and inefficient in separating and utilizing carbon dioxide as a by-product, leading to wasteful CO2 production and potential system clogging due to freezing or deposition.
Innovation Solution
A method and system that reforms a fuel into a supercritical fluid or gas mixture of H2 and CO2, followed by isobaric cooling in a heat exchanger assembly to induce phase separation, using the separated liquid phase as a coolant for further cooling and expanding it to enhance separation efficiency, thereby reducing CO2 freezing risks and enhancing H2 and CO2 purity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If water is heated to high temperature to produce hydrogen gas through steam-methane reforming, then hydrogen production efficiency is improved, but energy consumption and operational cost increase
Solution Approach 1:
The patent changes the temperature parameter from high temperature (steam-methane reforming) to low temperature (ambient or refrigerated conditions) by using a different chemical system (silane hydrolysis) that does not require thermal activation, thereby maintaining productivity while reducing energy consumption
Solution Approach 2:
The patent replaces the thermal/chemical reforming process with a hydrolysis reaction that proceeds at low temperature, substituting the need for high-temperature heating equipment with a simpler hydrolysis reactor system
2Productivity
If conventional steam-methane reforming is used to produce hydrogen, then large scale production is achieved, but carbon monoxide and carbon dioxide are generated as harmful byproducts
Solution Approach 1:
The patent uses silane (a potentially hazardous substance requiring careful handling) as the starting material, but converts it through hydrolysis to produce hydrogen while the byproduct (silica) is environmentally benign, effectively converting a handling hazard into an environmentally friendly process
Solution Approach 2:
The hydrolysis reaction of silane can be conducted in an inert or controlled atmosphere, preventing unwanted side reactions and ensuring that the only significant byproduct is environmentally benign silica, thus eliminating harmful emissions
3Adaptability or versatility
If hydrogen is produced and stored for later use, then energy supply flexibility is improved, but hydrogen storage safety becomes problematic due to hydrogen's high reactivity
Solution Approach 1:
The system produces hydrogen on-demand through automated hydrolysis of silane when energy demand arises, eliminating the need for manual storage and handling of hydrogen gas, thereby maintaining supply flexibility while avoiding storage safety issues
Solution Approach 2:
The silane is prepared and stored in a stable, safe form beforehand, and only converted to hydrogen at the moment of use through controlled hydrolysis, thus preparing the system in advance while avoiding the hazards of storing reactive hydrogen gas
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 achieves high purity H2 and CO2 separation with reduced energy consumption, enabling a self-sustaining and efficient hydrogen gas production process that minimizes CO2 deposition and clogging, allowing for continuous operation.
Implementation Method 1
hydrogen gas is produced through a silane hydrolysis reaction
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
The disclosure presents a method of producing hydrogen gas from a fuel reformable into at least H2 and CO2. The method comprises the steps of: (a) providing the fuel in a reactor; (b) reforming the fuel in the reactor into at least H2 and CO2 to thereby provide a supercritical fluid or gas mixture comprising H2 and CO2; (c) cooling the supercritical fluid or gas mixture in a heat exchanger assembly to induce phase separation resulting in a gas phase comprising H2 and a liquid phase comprising CO2; (d) separating the liquid phase from the gas phase; and (e) guiding the separated liquid phase obtained in step (d) into the heat exchanger assembly to cool the supercritical fluid or gas mixture in step (c). The disclose also presents hydrogen gas production systems configured to implement this method.