| 摘要 |
PROBLEM TO BE SOLVED: To prevent the freezing of a steam generator for generating steam to be supplied to a reformer and improve the start-up performance of the generator. SOLUTION: This reformer is provided with an ethylene glycol tank 26 and a pump 28 to enable the supply of ethylene glycol which is soluble in water and has a freezing point lower than water and a boiling point higher than water to a water-bath of a steam generator 30. When the outside air temperature detected by a temperature sensor 84 is decreased below a prescribed level (e.g. 0 deg.C) in the stopped state of the steam generator 30, ethylene glycol is mixed into the water bath of the steam generator 30. The content of the water bath becomes an aqueous solution of ethylene glycol having a freezing point lower than water to prevent the freezing of the solution. Since the vapor pressure of ethylene glycol is lower than that of water, its consumption is decreased compared with water during the operation of the steam generator 30. Accordingly, the amount of ethylene glycol to be supplied to the water bath in the next time can be decreased. |
