Steam Reforming Hydrogen Plant CO2 Capture via Water-Gas Shift
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current steam reforming processes for producing pure hydrogen face challenges in reducing carbon dioxide emissions, particularly due to high indirect and direct CO2 emissions from synthesis gas production and reformer furnace flue gas, with existing carbon capture methods being energy- and cost-inefficient, especially when separating CO2 from low-pressure flue gas streams.
Innovation Solution
A process and plant configuration that separates carbon dioxide from both the PSA tail gas and reformer furnace flue gas using cryogenic carbon dioxide capture and amine scrubbing, with integrated heat recovery and CO conversion stages to enhance energy efficiency and increase carbon dioxide separation rates, while minimizing hydrogen production restrictions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If carbon dioxide is separated from reformer furnace flue gas using conventional methods, then carbon dioxide emissions are reduced, but energy consumption and operating media consumption increase significantly
Solution Approach 1:
The patent applies preliminary action by performing CO conversion (water-gas shift reaction) on the reformer furnace flue gas before CO2 separation. This converts CO to CO2, increasing the CO2 concentration in the flue gas stream. By pre-concentrating the CO2 through this chemical conversion, the subsequent CO2 separation process becomes more efficient, requiring less energy and operating media while achieving the same emission reduction target.
2Object-generated harmful factors
If carbon dioxide separation rate is increased, then carbon dioxide emissions are reduced, but energy consumption and operating media consumption increase
Solution Approach 1:
The patent applies preliminary action by performing CO conversion (water-gas shift reaction) on the reformer furnace flue gas before CO2 separation. This converts CO to CO2, increasing the CO2 concentration in the flue gas stream. By pre-concentrating the CO2 through this chemical conversion, the subsequent CO2 separation process becomes more efficient, requiring less energy and operating media while achieving the same emission reduction target.
3Object-generated harmful factors
If conventional carbon capture methods are used on low-pressure flue gas streams, then carbon dioxide is removed, but the process becomes energy- and cost-inefficient
Solution Approach 1:
The patent applies preliminary action by performing CO conversion (water-gas shift reaction) on the reformer furnace flue gas before CO2 separation. This converts CO to CO2, increasing the CO2 concentration in the flue gas stream. By pre-concentrating the CO2 through this chemical conversion, the subsequent CO2 separation process becomes more efficient, requiring less energy and operating media while achieving the same emission reduction target.
4Object-generated harmful factors
If hydrogen production is restricted to reduce carbon dioxide emissions, then carbon dioxide separation rates improve, but hydrogen yield decreases
Solution Approach 1:
The patent applies the blessing in disguise principle by converting the harmful CO in the flue gas into beneficial CO2 through the water-gas shift reaction. This converted CO2 is then easily separable and can be captured. By transforming the harmful CO component into a separable CO2 form, the process achieves high CO2 separation rates without significantly impacting hydrogen production, as the CO conversion occurs in the flue gas stream rather than the main hydrogen production pathway.
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
This configuration achieves higher carbon dioxide separation rates with lower energy and operating media consumption, improving energy efficiency and reducing overall carbon dioxide emissions, making it a viable and flexible solution for reducing CO2 emissions in steam reforming plants producing pure hydrogen.
Implementation Method 1
the application of CO conversion, also referred to as water-gas shift reaction (WGS) or CO shift reaction
Implementation Method 2
separates carbon dioxide from both the PSA tail gas and reformer furnace flue gas using cryogenic carbon dioxide capture
Implementation Method 3
separates carbon dioxide from both the PSA tail gas and reformer furnace flue gas using cryogenic carbon dioxide capture and amine scrubbing
Implementation Method 4
The hot synthesis gas product gas is partially cooled in indirect heat exchange against process media to be heated in one or more heat exchangers
Data Source
AI summary
A process and a plant for producing pure hydrogen by steam reforming of a feed gas containing hydrocarbons, preferably natural gas or naphtha, with reduced carbon dioxide emissions are proposed. The reduction in carbon dioxide emissions is achieved in accordance with the invention in that carbon dioxide is separated both out of a PSA tail gas stream and out of the flue gas from the reformer furnace by means of suitable measures.