Patent ID: 7867322
Filing Date: 2011-01-11
Classification: B01D,F23J,Y02A,Y02C,Y02E

Abstract:
1. A method of cleaning a process gas containing carbon dioxide and sulphur dioxide, said method including removing, at least partly, carbon dioxide from the process gas by cooling the process gas, and bringing the cooled process gas into contact with an ammoniated solution or slurry absorbing at least a part of the carbon dioxide, comprising the steps of: cooling the process gas by bringing the process gas into direct contact with a cooling liquid in a gas-liquid contact device, and absorbing into the cooling liquid at least a part of the sulphur dioxide of the process gas, such that a cooling liquid containing sulphate is obtained, further cooling the cooled process gas from the gas-liquid contact device in an additional cooler to provide a further cooled, process gas, contacting the further cooled process gas with the ammoniated solution or slurry to remove, at least partly, carbon dioxide from the process gas, and to form a carbon dioxide rich ammoniated solution or slurry and a process gas containing ammonia, heating the carbon dioxide rich ammoniated solution or slurry to provide a carbon dioxide gas stream and the ammoniated solution or slurry for removing carbon dioxide from the process gas; and removing, at least partly, ammonia from the process gas containing ammonia by bringing the process gas containing ammonia into direct contact with the cooling liquid containing sulphate, wherein the cooling liquid containing sulphate is cooled by the process gas containing ammonia, the thereby cooled cooling liquid being utilized in cooling of the process gas.