Mixed Amine Solvent for CO2 Capture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current CO2 capture solvents, such as aqueous amine solutions, face inefficiencies including high energy requirements for regeneration, corrosion issues, slow absorption rates, and high solvent degradation, limiting their ability to effectively capture CO2 from power plant and industrial flue gases.
Innovation Solution
A mixed amine solvent composition comprising methyldiethanolamine (MDEA), potassium lysinate (KLyS), monoethanolamine (MEA), diethanolamine (DEA), aminomethyl propanol (AMP), piperazine (PZ), and other amines, along with promoters like lysine and taurine, enhances CO2 absorption and desorption rates, stability, and reduces energy consumption for regeneration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If aqueous amine solutions are used for CO2 capture, then CO2 absorption capability is achieved, but energy consumption for solvent regeneration becomes excessively high
Solution Approach 1:
The patent changes the chemical composition parameters of the solvent system by introducing a mixed amine formulation containing cyclic carbamate-forming amines (20-40 wt%), alkanolamines (30-50 wt%), and sterically hindered amines (10-30 wt%). This parameter change enables the solvent to achieve both high CO2 capture efficiency and reduced regeneration energy consumption through selective carbamate formation and decomposition at lower temperatures
Solution Approach 2:
The patent employs a composite amine solvent system combining multiple amine components with complementary properties. The cyclic carbamate-forming amines provide high CO2 capacity, alkanolamines enhance absorption rate, and sterically hindered amines reduce corrosion and degradation. This composite approach resolves the contradiction by integrating the strengths of different amine types into a single optimized solvent formulation
2Speed
If high concentration amine solvents are used to improve CO2 absorption rate, then absorption speed increases, but corrosion and solvent degradation worsen
Solution Approach 1:
The patent optimizes the concentration parameters of individual amine components within specific ranges rather than using high concentrations of single amines. The mixed formulation with controlled proportions of different amines achieves fast absorption rates while maintaining lower individual concentrations, thereby reducing corrosion and degradation issues
Solution Approach 2:
The patent introduces sterically hindered amines as intermediary components that mediate between the reactive carbamate-forming amines and the aqueous environment. These hindered amines reduce direct corrosion of equipment while maintaining CO2 absorption capability through their unique molecular structure that resists oxidation and degradation
3Productivity
If traditional amine solvents are used for CO2 capture, then CO2 absorption is achieved, but solvent degradation and emissions become excessive
Solution Approach 1:
The patent changes the chemical stability parameters by selecting amine components with inherent resistance to oxidation and thermal degradation. The specific combination of cyclic carbamate-forming amines, alkanolamines, and sterically hindered amines creates a solvent system that maintains high CO2 capture performance while significantly reducing solvent degradation rates and volatile emissions
Solution Approach 2:
The patent designs a solvent system that minimizes the need for frequent solvent replacement and reclamation. The enhanced stability of the mixed amine formulation reduces solvent loss and extends operational life, making the capture process more economically viable by reducing ongoing operational costs associated with solvent replenishment
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 solvent composition achieves high CO2 capture rates, with over 95% CO2 concentration in the gas stream, improved thermal and oxidative stability, reduced solvent emissions, and lower energy costs for regeneration, outperforming traditional solvents like 30 wt % MEA.
Implementation Method 1
aqueous amine solutions to absorb CO2 from CO2-containing gases
Implementation Method 2
promoters that enhance CO2 absorption and desorption reactions in the solvent compositions
Implementation Method 3
enhance CO2 absorption and desorption reactions in the solvent compositions
Implementation Method 4
lower energy costs for regeneration
Data Source
AI summary
An aqueous solvent composition useful for CO2 capture is described, that includes one or more CO2-sorbing amines, e.g., an amino acid salt and a tertiary or a sterically hindered amine. The solvent composition may include one or more promoters that are effective to enhance solvent characteristics such as (i) CO2 sorption capacity, (ii) CO2 sorption rate, (iii) CO2 desorption capacity, (iv) CO2 desorption rate, and (v) regeneration temperature, in relation to a corresponding solvent lacking the promoters. In relation to existing CO2 capture solvent compositions, the disclosed aqueous solvent composition provides high solvent CO2 capacity, high rate of CO2 absorption and desorption, high thermal and oxidative stability, low solvent regeneration energy, low solvent emissions, and low solvent toxicity.