Method for blowing out and purging double-section gas furnace

The invention discloses a method for blowing out and purging a double-section gas furnace. Before purging after blowing out, the system is under positive pressure all the time, so that the risk in explosion caused by air entering into the system when the system is under negative pressure can be avoided; the system is under non-negative pressure state during the whole purging process, so that production safety during the purging process can be guaranteed; coal gas generated in the whole slagging process is indirectly fed into the system and used as energy; no exhaust gas is emitted into atmosphere in the whole process, so that the pollution to environment can be avoided; increasing of phenol amount after a large amount of steam entering into furnace can be avoided in the whole process. Themethod disclosed by the invention is capable of overcoming the defect of the traditional purging method that gas between pipelines and equipment among air cooler inlet valve, electric fishing coke inlet valve and gas furnace