Introduction

The patent protects a new process and its related apparatus for the sequestration and conversion of CO2 from flue gases. The new process is obtained through the combination of two known technologies, which are Carbon Capture and Sequestration for CO2 recovery and Carbon Capture and Utilization for its conversion into compounds that enable circularity and decarbonization.

Technical features

The invention (TRL 4) consists of a combination of two processes, Carbon Capture and Sequestration and Carbon Capture and Utilization. This provides a single technology capable of capturing and chemically converting CO2 without the need for solvent regeneration.

The apparatus involves the complete overhaul of the traditional scheme, totally removing the solvent regeneration steps and inserting the CO2 conversion unit. CO2 capture is achieved through the use of the traditional mixture of water and amines. CO2 conversion takes place through a metathesis reaction following the supply of an appropriate salt; this is followed by a crystallization process to separate the carbonate formed; the lean solution is then available to be recycled to carry out a new capture cycle.

Possible Applications

• Conversion of CO2 into CaCO3;
• Fertilizer production from flue gas;
• Disposal of processing gypsum (CaSO4) with zero residues;
• Circularity for cement production;
• Circulation for the primary sector.

Advantages

• Deep removal of CO2 from rich or dilute streams;
• Greater reuse of CO2 than conventional plants;
• Limitations on the use of amine-based solvents.