Abstract:
A method for drying a wet CO2 rich gas stream from an oxy-combustion process that includes: compressing the wet CO2 rich gas stream to a drying process operating pressure, cooling the wet CO2 rich gas stream in at least one cooler, alternately drying the wet CO2 rich gas stream in at least one dryer which contains at least one desiccant bed and regenerating the desiccant bed by conducting a heated regenerating gas through the dryer in opposite direction to the flow direction of the wet CO2 rich gas stream, separating the dried CO2 rich gas stream in a purification process to a purified CO2 gas stream and a waste gas stream rich in nitrogen and oxygen, whereby the waste gas stream rich in nitrogen and oxygen is used as regenerating gas, and subsequently to the regeneration the dryer is purged at least once by a pressurized CO2 rich gas stream conducted from the compressor, and whereby the dryer is charged up to the drying process operating pressure with a pressurized CO2 rich gas stream conducted from the compressor before each drying process.
Abstract:
The present disclosure relates to a method of operating a boiler system that includes an oxyfuel boiler in which an oxygen stream and a fuel stream are combusted to generate a stream of flue gas, an oxygen gas source producing the stream of oxygen for the boiler, and a gas processing unit for cleaning and compressing at least a portion of the stream of flue gas generated in the boiler for producing a stream of pressurized fluid comprising carbon dioxide. The method includes operating the boiler system, at least for a period of time, in an evaporation mode, in which a stream of oxygen from the oxygen gas source in liquid form is evaporated prior to being introduced in the boiler by transferring heat energy to the stream of liquid oxygen from a first stream of carbon dioxide of the gas processing unit. The present disclosure further relates to a boiler system for an oxy-fuel process as well as to a power plant comprising such a system.