Two-Stage PSA for CO2 Capture and N2 Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for capturing CO2 and N2 from power plants are inefficient, reducing the efficiency of electricity generation and requiring significant energy, while existing natural sources of CO2 are insufficient to meet global demand for Enhanced Oil Recovery (EOR) and Enhanced Gas Recovery (EGR) applications.
Innovation Solution
A two-stage pressure swing adsorption (PSA) process that recycles exhaust gas to separate CO2 and N2 at the temperature and pressure of the combustion reaction, using a first adsorbent material to adsorb CO2 and then purging with a N2 stream, followed by a second adsorbent material with a steam purge to achieve high purity CO2 and N2 recovery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional CO2 capture methods are used, then CO2 can be captured from power plants, but the efficiency of electricity generation is reduced due to significant energy consumption
Solution Approach 1:
The patent divides the CO2 capture process into multiple stages using a multi-bed adsorption system. Different adsorbent materials are used in separate beds to selectively capture CO2 at different phases of the cycle, allowing for more efficient separation without requiring excessive energy input for a single-stage process.
Solution Approach 2:
The patent employs periodic pressure swing adsorption where the adsorption beds are cycled between high-pressure CO2 capture mode and low-pressure regeneration mode. This periodic operation allows continuous CO2 capture while using the pressure differential to drive the regeneration process with minimal additional energy input.
2Quantity of substance
If single-stage pressure swing adsorption is used, then CO2 can be recovered, but the manufacturing complexity and energy requirements increase
Solution Approach 1:
The system is segmented into multiple adsorption beds with different adsorbent materials, each optimized for specific conditions. This segmentation allows the process to achieve high CO2 recovery while distributing the complexity across multiple simpler, specialized units rather than one complex single-stage system.
Solution Approach 2:
The patent changes operating parameters such as pressure, temperature, and gas composition across different beds to optimize CO2 capture at each stage. By adjusting these parameters progressively through the multi-stage system, the process achieves high recovery efficiency without requiring any single stage to be overly complex.
3Quantity of substance
If CO2 is captured for EOR applications, then demand for CO2 can be met, but existing natural sources are insufficient to meet global demand
Solution Approach 1:
The patent enables power plants to serve dual purposes: generating electricity and producing CO2 for EOR applications. By capturing CO2 from their own emissions, power plants become self-sufficient CO2 sources, eliminating dependence on natural CO2 sources and pipeline infrastructure while meeting both power generation and CO2 supply needs.
Solution Approach 2:
The patent uses adsorption materials as intermediary substances to transfer CO2 from the power plant exhaust stream to the EOR injection stream. These adsorbents selectively bind and release CO2, enabling the transformation of waste emissions into a usable product for oil recovery without requiring direct physical connection to natural CO2 sources.
4Quantity of substance
If N2 is produced using cryogenic air separation, then N2 can be supplied for EGR or EOR, but the cost is higher than current technology
Solution Approach 1:
The patent designs the adsorption system to produce multiple products simultaneously: CO2 for EOR and N2 for EGR or EOR applications. This multi-functionality allows a single system to replace both cryogenic air separation plants and natural CO2 sources, reducing overall production costs while meeting diverse hydrocarbon recovery needs.
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 approach allows for efficient capture of CO2 and N2 with minimal energy loss, enabling simultaneous power generation and emission reduction, while providing high purity streams suitable for EOR and EGR applications.
Implementation Method 1
passing a stream of recycled exhaust gas into a first swing adsorption reactor comprising a first adsorbent material; adsorbing CO2 on the first adsorbent material
Implementation Method 2
passing the first purge output to a second swing adsorption reactor comprising a second adsorbent material; adsorbing CO2 on the second adsorbent material
Implementation Method 3
purging the second swing adsorption reactor with a steam purge to create an output from the second swing adsorption reactor
Data Source
AI summary
Systems and methods for using pressure swing adsorption to separate and/or capture resulting emissions are provided. A stream of recycled exhaust gas is passed into a first swing adsorption reactor comprising a first adsorbent material which adsorbs CO2. An enriched N2 stream is recovered from a forward end of the first swing adsorption reactor. The pressure in the first swing adsorption reactor is reduced. The first swing adsorption reactor is purged with a portion of the first N2 stream recovered from the first swing adsorption reactor. The first purge output is passed to a second swing adsorption reactor comprising a second adsorbent material which adsorbs CO2. A second N2 stream is recovered from the second swing adsorption reactor. The pressure in the second swing adsorption reactor is reduced. The second swing adsorption reactor is purged with a steam purge.