Amine Solvent Viscosity Reduction for Acid Gas Removal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing solvents for removing acid gases like hydrogen sulphide and carbon dioxide from natural gas and synthesis gas have limitations in viscosity, loading capacity, and energy consumption, which affect the efficiency and cost of gas purification processes.
Innovation Solution
A solvent composition comprising MDEA, thiodiglycol, amino ethyl piperazine, and potassium carbonate, optimized to reduce viscosity and enhance absorption kinetics, allowing for efficient removal of acid gases at high partial pressures with reduced energy consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If conventional solvents are used for removing acid gases, then acid gas removal capability is achieved, but viscosity is high which reduces absorption kinetics
Solution Approach 1:
The patent changes the chemical composition parameters of the solvent system by incorporating specific ratios of MDEA (30-45 wt%), AEP (5-10 wt%), thiodiglycol (10-25 wt%), and potassium carbonate (0.1-2.0 wt%). This parameter optimization reduces viscosity to less than 11 cP at 40°C while maintaining effective acid gas removal capability, thereby improving absorption kinetics without sacrificing removal efficiency.
2Quantity of substance
If solvent concentration is increased to improve loading capacity, then acid gas absorption capacity increases, but viscosity increases reducing fluidity
Solution Approach 1:
The patent creates a composite solvent system combining multiple components (MDEA, AEP, thiodiglycol, potassium carbonate, and water) in optimized proportions. This composite formulation achieves high loading capacity for acid gases while maintaining low viscosity through synergistic interactions between components, particularly the role of thiodiglycol and potassium carbonate in reducing overall system viscosity despite high active solvent concentrations.
3Productivity
If high partial pressure conditions are used to improve absorption efficiency, then acid gas removal effectiveness increases, but energy consumption increases
Solution Approach 1:
The patent optimizes operational parameters including temperature (15-90°C) and pressure (10-150 bar) ranges for the absorption process. By maintaining the solvent at optimized composition, the system achieves high absorption efficiency even at moderate conditions, reducing the energy penalty associated with extreme pressure and temperature requirements while maintaining deep removal of CO2 and H2S.
4Speed
If solvent composition is optimized for low viscosity, then absorption kinetics improve, but loading capacity may be reduced
Solution Approach 1:
The patent employs a composite solvent formulation where MDEA provides high loading capacity through chemical absorption mechanisms, while thiodiglycol and potassium carbonate contribute to viscosity reduction. The amine activator AEP enhances the overall absorption kinetics. This composite approach allows simultaneous optimization of loading capacity, kinetics, and viscosity by leveraging the complementary properties of each component.
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 achieves improved acid gas absorption kinetics and selectivity, reducing the overall energy consumption and operational costs by maintaining a low viscosity and efficient gas separation, enabling deep removal of CO2 and H2S without additional treatment steps.
Implementation Method 1
aqueous solution containing water, thiodiglycol, Methyl Diethanol Amine (MDEA), amine ethyl piperazine (AEP) as amine activator and potassium carbonate
Implementation Method 2
an aqueous solution containing water, thiodiglycol, Methyl Diethanol Amine (MDEA)
Implementation Method 3
Additionally, this disclosure relates to an absorbent liquid, which has a more optimal viscosity and load carrying capacity, that can be used in a purification process for removal of acid gases
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A solvent and method for removing carbon dioxide from a gaseous mixture flow with high carbon dioxide partial pressures are disclosed. The solvent includes a secondary or tertiary amine, an amine activator, a physical solvent (e.g., thioalkanol), and a carbonate buffer. The solvent contains less than about 60% by weight of water and is in a single liquid phase.