TCM report; CO₂ Capture – Operational and process control

Through more than 10 years of technology testing campaigns with 24/7 operation. TCM have developed significant learnings and experience in  this area predominantly on the flexible amine plant but also on other TCM test sites.

Long experience with CO₂ capture

TCM has generated over 20,000 hours of test data with the non-proprietary MEA and CESAR1 amine solvents. True investigating and documenting various phenomena in the capture process. A range of solvent systems, flue gas compositions, process parameters, operating strategies and analysis techniques have been tested to enhance understanding, improve performance and reduce risks and costs associated with CO₂ capture. 6 different publications have been published. – We are proud of the experience we have gained and see that our test results are now being used by more and more full-scale actors. And we are more than happy to share our expertise, concludes Ismail Shah, managing director.

The plant is affected by load changes

The value of having flexible CCS facilities that can handle load changes from power plants becomes greater with a higher proportion of renewables (e.g. solar energy and wind) in the energy supply. Start-up and shutdown cycles of power plants with CCS are becoming increasingly frequent. Which could potentially increase fugitive emissions. While the start-up and shutdown of power plants has been characterized. The effect of start-up and shutdown on CCS plants is still unclear. That is why TCM, together with various partners, has looked at this, among other things.

Quantifying residual CO₂ emissions, energy requirements and time requirements at start-up and shutdown in amine-based CO₂ capture plants

A series of start-up and shutdown tests were carried out in March, June and November 2020 at the technology centre Mongstad (TCM). In these tests, CESAR-1 was used to capture CO₂ from flue gas (~4 mol% CO₂) coming out of the natural gas-fired CCGT (combined cycle gas turbine) combined with flue gas from heat and power plant (CHP). These tests provide valuable insight into how key process parameters and operating strategies can help minimize disturbances (e.g. time and energy requirements) and CO₂ emissions during startup and shutdown of CO₂ capture plants.

Performance improvement can be achieved by:

• Optimizing the solvent volume
• The time of power availability
• Key process parameters such as solvent CO₂ load or amine concentration

Source: Evaluating performance during start-up and shut down of the TCM CO₂ capture facility (2022)

CO₂ Product Quality

The quality of the CO₂ product stream produced by the capture process, including the levels and types of impurities present. This is an increasingly important topic due to the impact on CO₂ transport and storage. This has been reflected in CO₂ specifications set by projects such as Northern Lights. In 2018, TCM published a full characterisiation of the CO₂ product stream with analysis by Airborne Labs supported by TCM online instrumentation. This also included testing on the effects of solvent degradation and certain process parameters on the quality of the CO₂ product stream.
Source: CO₂ product quality: assessment of the range and level of impurities in the CO₂ product stream from MEA testing at the Technology Centre Mongstad (TCM) (2018.

The six reports that have been published within this subject area

• Evaluating performance during start-up and shut down of the TCM CO₂ capture facility (2022)
• Start-up and Shutdown Protocol for Natural Gas-fired Power Stations with CO₂ Capture (2022)
• Demonstrating flexible operation of the Technology Centre Mongstad (TCM) CO₂ capture plant (2020)
• Demonstration of non-linear model predictive control of post-combustion CO₂ capture processes (2019)
• Experimental results of transient testing at the amine plant at Technology Centre Mongstad: Open-loop responses and performance of decentralized control structures for load changes (2018)
• Scale-up and Transient Operation of CO₂ Capture Plants at CO₂ Technology Centre Mongstad (2014)