METHOD AND SYSTEM FOR TREATING EXHAUST GAS, AND METHOD AND APPARATUS FOR SEPARATING CARBON DIOXIDE

摘要

A method for treating an exhaust gas, which comprises passing an exhaust gas discharged from a boiler using coal or LNG as a fuel through a cooling medium, to cool the exhaust gas to a first temperature at which carbon dioxide is not solidified and a nitrogen oxide or a sulfur oxide is liquefied or solidified, to thereby liquefy or solidify a nitrogen oxide or a sulfur oxide contained in the above exhaust gas as a harmful gas component and separate it from the exhaust gas and simultaneously remove the moisture contained in the exhaust gas, and then cool the resultant exhaust gas to a second temperature at which carbon dioxide is solidified, to thereby solidify the carbon dioxide contained in the exhaust gas and separate the carbon dioxide from the exhaust gas.