Gas Separation Using LCST Solvents for Low-Energy CO2 Capture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current CO2 capture systems are costly and energy-intensive, limiting their widespread adoption for reducing greenhouse gas emissions, particularly due to high energy consumption in processes like steam-based elevated temperature heat generation and solubility-driven absorption technologies.
Innovation Solution
A novel gas separation process that utilizes physical solvents undergoing phase transitions at critical solution temperatures to change the number and composition of liquid phases, enhancing solubility and desorption kinetics, and incorporating antisolvents and membranes for efficient CO2 capture and separation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If physical absorption CO2 separation technologies are used, then CO2 can be separated from gas streams, but significant electricity is consumed in compression/pressurization and pumping
Solution Approach 1:
The patent employs phase transitions of the physical solvent between single-phase and multi-phase states to drive CO2 absorption and desorption. During absorption, the solvent is in a single-phase state with high CO2 solubility. During desorption, the solvent transitions to a multi-phase state where CO2 solubility is reduced, enabling spontaneous release of CO2 without requiring significant compression or heating energy.
Solution Approach 2:
The patent changes physical parameters (temperature, pressure) to induce phase transitions in the solvent system. By controlling these parameters, the solvent's CO2 solubility is dynamically adjusted - high solubility during absorption and low solubility during desorption - eliminating the need for continuous high-energy compression and pumping operations.
2Productivity
If elevated temperature heat is used for CO2 capture, then CO2 separation is achieved, but electricity costs increase by over 70%
Solution Approach 1:
The patent replaces elevated temperature thermal processes with phase transition-driven separation. The solvent's phase change between single-phase (high CO2 affinity) and multi-phase (low CO2 affinity) states enables CO2 capture and release at near-ambient temperatures, eliminating the need for steam generation and associated electricity costs.
Solution Approach 2:
The patent substitutes thermal energy input (steam heating) with a phase transition mechanism that naturally provides the necessary energy swing for CO2 separation. This replaces the mechanical/thermal system with a chemical-physical system that operates at lower energy input.
3Productivity
If the solubility of acid gas is increased in physical solvent, then absorption efficiency improves, but more energy is required during desorption to regenerate the solvent
Solution Approach 1:
The patent uses phase transitions to create a natural solubility swing. In the single-phase state, the solvent exhibits high acid gas solubility for efficient absorption. Upon transitioning to the multi-phase state, solubility naturally decreases, enabling easy desorption without requiring excessive energy input for solvent regeneration.
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 reduces energy consumption and costs by optimizing solubility and desorption processes, enabling more efficient and cost-effective CO2 capture, potentially displacing unsustainable sources and lowering the market price of pure CO2.
Implementation Method 1
A novel gas separation process that utilizes physical solvents undergoing phase transitions at critical solution temperatures to change the number and composition of liquid phases
Implementation Method 2
enhancing solubility and desorption kinetics
Implementation Method 3
employ separation technologies based on physical absorption, chemical absorption, gas phase membrane separation, or adsorption
Implementation Method 4
incorporating antisolvents and membranes for efficient CO2 capture and separation
Data Source
AI summary
The invention pertains to processes for separating water from air. The processes may employ using an LCST solution with or without subsequent reverse osmosis, nanofiltration, or ultrafiltration.