Method for refining argon gas and recovering and refining apparatus for argon gas

A method for refining an argon gas, in which oxygen is added to the argon gas containing at least one of hydrogen, carbon monoxide, and oxygen as impurities so that the hydrogen and the carbon monoxide contained in the argon gas are converted into water and carbon dioxide by using a catalytic reaction in a catalyst tower, or hydrogen is added to the argon gas so that the oxygen contained in the argon gas is converted into the water by using a catalyst reaction in the catalyst tower, and at least one of the hydrogen, the carbon monoxide, and the oxygen is thereby removed from the argon gas,

• the method comprising the steps of:
• installing (A) at least one of oxygen adding means and hydrogen adding means, (B) the catalyst tower, and (C) detecting means in this order toward a downstream side,
• monitoring at least one of the hydrogen, the carbon monoxide, and the oxygen at the detecting means installed on an outlet side of the catalyst tower;
• and
• at least one of adding the oxygen to the argon gas at the oxygen adding means installed on an inlet side of the catalyst tower when any one of the hydrogen and the carbon monoxide is detected at the detecting means installed on the outlet side of the catalyst tower, and adding the hydrogen to the argon gas at the hydrogen adding means installed on the inlet side of the catalyst tower when the oxygen is detected at the detecting means installed on the outlet side of the catalyst tower,
• wherein the oxygen or the hydrogen to be added is intermittently added to the catalyst tower relative to continuous supply of the argon gas to the catalyst tower, and at least one of the hydrogen, the carbon monoxide, and the oxygen contained in the argon gas is thereby removed,
• wherein the method comprises none of the steps of, on a downstream side of the catalyst tower, removing oxygen, which is surplus due to the catalytic reaction, by an oxidative reaction with a metal, and removing hydrogen, which is surplus due to the catalytic reaction, by a reductive reaction with a metal.