Externally Supported Sorbent Bed for Low-Pressure CO2 Air Capture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gas separation technologies face challenges in achieving low pressure drop and high mass transfer rates for capturing trace components like CO2 from large air volumes, particularly in direct air capture systems, due to the low concentration of CO2 in atmospheric air, leading to high energy requirements and inefficient process economics.
Innovation Solution
A particulate sorbent bed structure with flexible porous material containing short-distance packed beds and external support features, allowing for thin sorbent layers and controlled gas flow directionality, enhancing mass transfer and thermal conductivity while minimizing pressure drop.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If conventional packed bed columns or fluidized beds are used for gas separation, then mass transfer rates are improved, but pressure drop increases significantly
Solution Approach 1:
The sorbent bed is segmented into multiple thin layers separated by permeable support structures. This segmentation allows gas to flow through multiple pathways while maintaining close contact with sorbent particles, achieving high mass transfer rates without the high pressure drop of conventional single-layer packed beds.
Solution Approach 2:
The invention transitions from a conventional vertical packed bed configuration to a horizontal layered structure with permeable supports. This dimensional change allows gas flow to occur in multiple directions (through the sorbent layers and through the permeable supports), reducing flow resistance while maintaining effective mass transfer surface area.
2Stress or pressure
If sorbent layer thickness is reduced to minimize pressure drop, then pressure drop decreases, but mass transfer efficiency deteriorates
Solution Approach 1:
Instead of using a single thick sorbent layer, the invention divides the total sorbent volume into multiple thin layers. Each thin layer maintains low flow resistance, while the stacked configuration provides sufficient total mass transfer surface area, achieving both low pressure drop and high mass transfer efficiency.
Solution Approach 2:
The invention uses multiple permeable support layers distributed throughout the sorbent bed, providing additional flow pathways beyond what a single support would offer. This excessive support structure ensures minimal flow resistance while maintaining structural integrity of the thin sorbent layers.
3Quantity of substance
If large air volumes are processed to capture trace CO2, then CO2 capture quantity is improved, but energy consumption increases
Solution Approach 1:
The permeable support structures create a low-resistance environment for gas flow, reducing the energy required to move large volumes of air through the system. The optimized flow pathways minimize pressure drop, thereby reducing pumping energy consumption while maintaining the capability to process large air volumes for trace CO2 capture.
4Stress or pressure
If sorbent material is arranged in thin layers, then pressure drop is reduced, but structural stability deteriorates
Solution Approach 1:
Permeable support structures serve as intermediaries between the thin sorbent layers and the gas flow. These supports provide mechanical stability to the thin layers while allowing gas to pass through, preventing layer collapse or displacement without creating significant flow resistance.
Solution Approach 2:
The invention uses permeable support structures that can be flexible yet structurally sound, allowing the thin sorbent layers to maintain their configuration under gas flow conditions. These supports provide the necessary mechanical integrity while maintaining porosity for gas flow.
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 structure achieves efficient CO2 capture with reduced energy consumption and increased mass transfer rates, enabling economical and compact systems for direct air capture.
Implementation Method 1
flexible porous material containing short-distance packed beds
Implementation Method 2
particulate sorbent bed structure for adsorption gas separation process
Implementation Method 3
external support features, allowing for thin sorbent layers
Implementation Method 4
enhancing mass transfer and thermal conductivity
Data Source
AI summary
A gas separation unit for the separation of carbon dioxide from air is proposed for use in a cyclic adsorption/desorption process and using a loose particulate sorbent material. The loose particulate sorbent material is disposed within an internal volume of an external support structure and supported by the external support structure, the external support structure comprising a plurality of base portions, deflected portions, and openings. The sheets are arranged parallel defining an inlet face and an outlet face, are arranged with a distance in the range of 0.1-2.5 cm (preferably 0.1-0.5 cm), and the inflow passes through the inlet face, subsequently through the particular sorbent material located in the cavity of the respective layer, subsequently to exit the layer through the outlet face to form the gas outflow. Directionality of the inflow and the outflow through the external support structure is controlled by the deflected portions of the external support structure.