The Environment Agency (EA) published guidance on July 2nd on post-combustion CO2 capture best available techniques (BAT) for the control of industrial emissions. The techniques listed aim to provide the best instructions in minimizing emissions from the post-combustion carbon capture process.
The guidance is suitable for both retrofitted plants and new constructions. It is for operators that design the carbon capture plants as well as prepare the applications for the environmental permit.
Regulatory staff that set conditions in environmental permits can also use it together with any other organization that wants a deeper understanding of the best post-combustion carbon capture standards being applied.
Permanent geological storage requires an environmental permit, being a “Part A(1)” process and capture could be subject to permitting as an associated activity to the combustion process. The guidance also doesn’t include carbon capture for utilization although some pointers are relevant in terms of usage of amine capture solvents.
Major CO2 Capture Instructions
The most critical highlight of the EA guidance is that capturing 95% of emissions is considered BAT of the carbon capture process. The rate of 95% could be referred to through a period of time like a year or a momentary performance.
If a power plant processes less than the full flue gas capacity, the amount of the CO2 absorbed should be calculated accordingly so it always captures 95% of the CO2 gas coming through the absorber.
A major part of the guidance is also reducing flue gases like nitrogen oxides. They can pose a problem as they can react with amine-based solvents to produce stable nitrosamines and many of them are carcinogenic. Therefore, the guidance calls for a reduction of the nitrogen oxide levels to as little as practically possible along with the CO2 capture from flue gas.
It also includes other impurities like metals, chlorine and ash that need to be kept out of the solvent to ensure satisfactory operation. The carbon capture power plant is said to abate those impurities before the residual flue gases get released into the atmosphere.
The EA’s regulations are identifying power plants with carbon capture and storage as an emerging technology and meet the need for developing monitoring methods and standards to ensure the effective elimination of GHG emissions.