How it works, generally:
The fuel is put into a special container to burn. The nitrogen is pulled off the air mix. The remainder in the container is heated to a high temperature and oxygen is injected. A burst flash is created. Because the "air " is off, nearly pure carbon dioxide is produced.
This is pumped off and stored to be put down pipelines etc. The heat generated in the process is used to make the steam to run the turbines etc. Consider; the priorities are actually reversed. Instead of making steam your process is making carbon dioxide and the steam is incidental to it.
Plants will have to be completely re built or new plants built. This isn't about picking stuff out of a smokestack and it is very expensive! And, we will pay.