| 摘要 |
PURPOSE:To obtain an immersion tube heating type heat insulating furnace, which reduces the cost of energy to be consumed, by bringing a combustion gas into contact with a combustion cylinder at a portion therein, which is immersed in molten aluminum, and alternately carrying out combustion by a pair of burners for a short period of time while feeding combustion air having a high temperature close to a temperature of a combustion exhaust gas. CONSTITUTION:Combustion is carried out alternately by a pair of burners 5, 6 to warm one of heat accumulation bodies 7 and the interior of one of combustion cylinders 3. The combustion cylinder 3 is heated from its bottom by a flame and radiant heat of a combustion gas. Molten aluminum warmed from the bottom of the combustion cylinder 3 is convected, agitated and uniformly heated. In this case, since combustion air to be fed to the burner 5 is fed into a burner body after it is preheated by direct contact with the heat accumulation body 7 for a short period of time, the combustion air has a high temperature close to a temperature of an exhaust gas. Accordingly, when the combustion air is mixed with fuel ejected from a fuel nozzle 15, it is stably burnt even in the case of a small amount of fuel, so that a combustion gas having a high temperature can be obtained. |
