| 摘要 |
PURPOSE:To reduce baking time and outgassing, and produce the oxide film of a good quality on the inner wall of pipe by providing outside a cold insulating tank a heating device for heating the air to be supplied to the cold insulating tank to a temp. higher than that for baking in the product nitrogen line. CONSTITUTION:A control device 40d activates a feed air compressor 1 to operate with a valve 4 open, and valves 2 and 3 closed to produce compressed feed air, which is then supplied to a feed air cooler 9 and after cooling is sent into adsorption towers 10a and 10b. The adsorption towers 10a and 10b remove contained H2O and CO2 and carry them out. By the control device 40d, moreover, a temp. regulator 24 is so controlled as to operate a feed air heater 31 to produce a high temp. feed air, which is then sent into a cold insulating tank 11. In this way the amount of the heat being supplied into the cold insulating tank is decreased to control the use amount of stored liquid for keeping the cold insulating tank cold. Therefore, the baking time of product nitrogen line is shortened and the oxide film of a good quality can be produced on the inner wall of pipe. |
