Rotary Contactor for Vehicle CO2 Capture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current onboard CO2 capture systems for motor vehicles face challenges in achieving compactness, fast heat and mass transfer, and minimal pressure drop due to large flow rates and limited space, making them ineffective for rapid adsorption and regeneration cycles.
Innovation Solution
A rotary contactor system with a rotating wheel coated with a solid sorbent is used, where the exhaust gas is directed through a cooled section for adsorption and then heated to release CO2, utilizing the vehicle's hot exhaust or fluid for temperature differences, and an energy recovery device generates energy for compressing the released CO2.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If sorbents are packed in static beds for CO2 capture, then the system structure is simple, but the pressure drop increases and heat and mass transfer are limited
Solution Approach 1:
The patent applies the dynamics principle by transitioning from static bed packing to a rotary contactor system where the sorbent-coated wheel rotates continuously. This dynamic configuration allows different sectors of the wheel to be in different operational states (adsorption, heating, cooling) simultaneously, enabling fast heat and mass transfer while maintaining a compact structure suitable for mobile applications.
Solution Approach 2:
The rotary contactor wheel is divided into multiple sectors that can be independently controlled for different functions. The wheel includes a cooled sector for CO2 adsorption, a heated sector for CO2 release, and potentially a cooling sector for regenerating the sorbent. This segmentation allows simultaneous performance of multiple operations, improving heat and mass transfer efficiency without increasing overall system complexity.
2Volume of moving object
If sorbent systems are designed for compactness, then space is reduced, but the rate of transport of heat and mass is insufficient for short cycle operation
Solution Approach 1:
The rotary contactor introduces dynamic motion to enhance heat and mass transfer rates within a compact volume. The continuous rotation of the sorbent-coated wheel creates repeated exposure to hot and cold gases, intensifying the transfer processes. This dynamic approach allows the system to achieve high productivity in a small footprint, suitable for onboard vehicle installation.
Solution Approach 2:
The system employs periodic action through the cyclic rotation of the contactor wheel, which repeatedly exposes the sorbent material to alternating hot and cold gas streams. This periodic exposure accelerates the adsorption and desorption cycles, enabling fast heat and mass transfer rates that support short cycle operation while maintaining compact dimensions.
3Loss of energy
If the rotary contactor uses hot fluid for heating and exhaust gas for cooling, then energy efficiency is improved, but the system complexity increases
Solution Approach 1:
The system applies self-service by using the vehicle's own hot exhaust gases to provide both the heating function (for CO2 release) and the cooling function (for sorbent regeneration and exhaust gas cooling). This internal resource utilization eliminates the need for external heating and cooling utilities, improving energy efficiency while the integrated design keeps complexity manageable through shared infrastructure.
Solution Approach 2:
The exhaust gas stream serves multiple functions within the system: it acts as the cooling medium for the adsorption sector, provides the heating medium for the desorption sector after being redirected, and ultimately serves as the regeneration medium for the cooling sector. This multi-functionality of the exhaust gas stream improves energy efficiency by maximizing the utilization of thermal energy already present in the vehicle exhaust.
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 enables a compact, efficient CO2 capture system with a short cycle time, reduced pressure drop, and enhanced heat and mass transfer, effectively capturing and compressing CO2 for storage onboard vehicles.
Implementation Method 1
The CO2 of the exhaust gas is adsorbed with a sorbent of the cooled section of the rotary contactor
Implementation Method 2
The cooled section of the rotary contactor is heated with a hot fluid of the vehicle to release the adsorbed CO2
Implementation Method 3
The heated section of the rotary contactor is cooled to convert the heated section of the rotary contactor back to the cooled section
Data Source
AI summary
Systems and methods for capturing carbon dioxide (CO2) in exhaust gases of a vehicle include delivering the exhaust gas to a cooled section of a rotary contactor, the rotary contactor including openings that extend from a first side of the rotary contactor to a second side of the rotary contactor. The CO2 of the exhaust gas is adsorbed with a sorbent of the cooled section of the rotary contactor, where the non-CO2 components of the exhaust gas pass through the openings. The cooled section of the rotary contactor is heated with a hot fluid of the vehicle to release the adsorbed CO2 and convert the cooled section of the rotary contactor to a heated section of the rotary contactor. The heated section of the rotary contactor is cooled to convert the heated section of the rotary contactor back to the cooled section of the rotary contactor.