Lanran CCUS Application Solutions Series | Case I

Case: 100,000 t/a Green Methanol Demonstration Project at Henan

Background:

The chemical absorption method using amine solutions is one of the most widely applied CO₂ capture methods. Amines (such as MDEA – Methyldiethanolamine) react with acidic gases like CO₂ to form stable compounds. However, over time, impurities such as sodium (Na⁺), ammonium (NH₄⁺), chloride (Cl⁻), and organic degradation products accumulate in the solvent. These react with amines to form Heat Stable Salts (HSS), which cannot be removed during thermal regeneration. If not controlled, HSS accumulation leads to: Reduced effective amine concentration (lower capture efficiency); equipment corrosion and fouling; higher steam consumption during regeneration; solvent foaming and loss.

A venture producing green methanol fuel by reacting captured CO₂ with hydrogen from coke oven gas — requires large-scale and continuous amine purification. The target was to reduce HSS content to below 1% to ensure stable long-term CO₂ capture.

Lanran Solution:

Lanran supplied its AC25-240 containerized Electrodialysis (ED) system. Electrodialysis (ED) is a membrane separation process where ions are transported through ion exchange membranes under a direct current (DC) electric field.

In this case, ED selectively removes negatively charged HSS anions (such as formate, sulfate, oxalate) from the amine solution, while keeping the active amines (MDEA and others) in circulation.

The process does not require chemical regenerants, reducing operational costs and secondary waste.

Technology Advantages:

✔ ED process – clean, efficient, chemical-free regeneration.

✔ Containerized design – compact, modular, and easy to install.

✔ Ensures continuous, high-purity solvent recovery, enabling stable CCUS–to–methanol operation.

Results & Impact:

CO₂ capture: 160,000 t/a from industrial flue gases.

Hydrogen source: coke oven gas (H₂).

Product: 100,000 t/a green methanol, a clean alternative fuel.

Amine solvent stabilized, with HSS maintained below 1%.