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Cryogenic carbon capture engineering as sustainable prowess in managing CO2 emission abatement
By Ir Dr Alex GBAGUIDI

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Among the different carbon capture utilisation and storage technologies, the recently developed cryogenic carbon capture engineering (CCCE) method is found to be the most mature engineering prowess for its remarkably high CO2 recovery and purity (99.99%). The significant advantage of the CCCE process lies in its easy retrofit to existing systems, handling gas stream’s impurities without using chemical solvents and secondary pollution. CCCE consists of separating CO2 from light gases, cooling the gases, separating and pressurising the solids; and warming all streams to produce a CO2-depleted stream at ambient pressure and temperature. CCCE also recovers all gas moisture and impurities in separable streams.

 

Major advantages of CCCE include: (i) a bolt-on retrofit technology without steam, (ii) water and all pollutants recovery in addition to CO2 from the flue gas, (iii) highly efficient and cost-effective energy storage at grid scale, (iv) natural gas storage (under energy storage option), (v) lower cost than alternatives, and (vi) small footprint with minimal disruption to existing plants.

 

Moreover, a sustainable energy solution (SES) has been developed within the process to significantly scale up CCCE through several levels up to 10-80 tonnes of CO2/day, which have been successfully tested in different fields including utility-scale power plants, solid municipal waste treatment facilities, cement plants, heating plants, and other industrial sites. SES has demonstrated the potential for CCCE in energy storage and direct air capture in innovative and cost-effective ways.

 

The SES process recovers energy by using the stored refrigerant to drive CCCE, and avoiding the parasitic power losses associated with refrigerant generation. During energy recovery, the SES produces high-pressure natural gas-vapour which can either be returned to the pipeline or be burned in an auxiliary simple-cycle gas turbine.

 

In sum, the CCCE process has demonstrated its potential to contribute to CO2 management as (i) a cost-effective and energy efficient CO2 capture system, (ii) an efficient and inexpensive grid-scale energy storage system, and (iii) a direct air capture system. In the context of net-zero by 2050, it could represent one of the most strategically competitive and sustainable engineering prowess.

 

This article is contributed by Ir Dr Alex Gbaguidi with the coordination of the Environmental Division.

 

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