Fuel gas heater, support structure for fuel gas heater, and method for cleaning fuel gas heater

A method for cleaning a fuel gas heater, the fuel gas heater comprising:

• a container having a hollow shape extending in a horizontal direction;
• a gas inflow chamber defined in one end portion in a longitudinal direction of the container and having a gas inlet for fuel gas;
• a gas outflow chamber defined in the one end portion in the longitudinal direction of the container and having a gas outlet for the fuel gas;
• a plurality of U-shaped heat transfer pipes disposed in an inside of the container, the heat transfer pipes each having one end portion communicating with the gas inflow chamber and another end portion communicating with the gas outflow chamber;
• a heating medium supply port through which a heating medium is supplied to the inside of the container;
• a heating medium discharge port through which the heating medium is discharged from the inside of the container;
• a gas inflow chamber maintenance opening disposed to face positions at which the heat transfer pipes communicate with the gas inflow chamber;
• a gas inflow chamber open/close lid that enables the gas inflow chamber maintenance opening to be opened and closed;
• a gas outflow chamber maintenance opening disposed to face positions at which the heat transfer pipes communicate with the gas outflow chamber;
• and
• a gas outflow chamber open/close lid that enables the gas outflow chamber maintenance opening to be opened and closed, the method comprising:
• removing the gas inflow chamber open/close lid and the gas outflow chamber open/close lid;
• inserting a cleaning nozzle in the gas inflow chamber through the gas outflow chamber maintenance opening and the gas inflow chamber maintenance opening, and
• injecting a blast cleaning material from the cleaning nozzle into the one end portions of the heat transfer pipes.