JP2786562B

• Main Authors: YOSHIDA KUNIHIKO, SHIMOJO SHIGERU, KAWASAKI MASAMI, SETO TOORU, KITAMURA KOICHI, FUJII MASUMI, HOTSUTA ZENJI, MITSUOKA SHIGEAKI, KARASAKI MUTSUNORI, IIJIMA MASAKI, KOBAYASHI KENJI, SUDA TAIICHIRO
• Format: Patent
• Language: English
• Published: 13.08.1998
• Edition: 6
• Subjects: PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; SEPARATION; TRANSPORTING

PURPOSE:To unnecessitate a storage facility, etc., of liquid ammonia in a denitration process by recovering ammonia included in combustion exhaust gas for CO2 removing treatment which is brought into contact with water solution of alkanolamine to use it as a reducing agent in the denitration process. CONSTITUTION:NH3 in gas given by CO2 removing treatment is reacted with CO2 in CO2 contg. water to form ammonium carbonates which are absorbed by water. Since the ammonium carbonates are decomposed into NH3, water and CO2 at >=70 deg.C, NH3 is easily regenerated by a method, such as that of blowing in air of >=100 deg.C. The regenerated NH3 together with CO2 which is similarly regenerated in the gaseous state is separated from water in a NH3 separation drum to be conveyed to a denitration process B. Therefore, a storage facility, etc., of NH3 which is difficult to handle are not required for the denitration process. On the other hand, diffusion of NH3 from a CO2 removing treated combustion exhaust gas exhaust opening to the outside of the system is effectively prevented and NH3 recovered from the CO2 removing process is effectively used as a reducing agent for the denitration process.