本发明公开了一种高炉炉顶料罐放散煤气全回收系统及其安全检修方法，在整个料罐放散煤气全回收系统标高的最高点、引射阀组前和第二除尘器顶分别设置三根放散管，在第二除尘器的切断阀前、煤气管网接入阀组前设置氮气吹扫点。通过放散管以及氮气吹扫的配合，可以实现放散煤气回收系统内煤气向氮气的置换，将放散煤气回收系统内气体的CO含量降低至安全值，不会威胁维修人员的安全。在放散煤气回收系统恢复使用前，通过放散管以及氮气吹扫的配合，可以实现放散煤气回收系统内空气向氮气的置换，将放散煤气回收系统内气体的O₂含量降低至安全值，避免放散煤气在回收管网内煤气和氧气的混合发生爆炸，达到安全检修目的。

The invention discloses a full recovery system of blowdown gas from the top of blast furnace charge tank and its safety maintenance method. Three blowdown pipes are set up at the highest point of the elevation of the full recovery system of blowdown gas from the whole charge tank, in front of the ejector valve group and on the top of the second dust collector respectively. Nitrogen purging points are set up in front of the cut-off valve of the second dust collector and before the gas pipe network is connected to the valve group. Through the cooperation of the release tube and nitrogen purging, the replacement of gas to nitrogen in the release gas recovery system can be realized, and the CO content of gas in the release gas recovery system can be reduced to a safety value, which will not threaten the safety of maintenance personnel. Before the recovery and use of the released gas recovery system, the replacement of air to nitrogen in the released gas recovery system can be realized through the cooperation of the released pipe and nitrogen purging, and the O₂ content of the gas in the released gas recovery system can be reduced to the safety value, so as to avoid the explosion of the mixed gas and oxygen in the recovery pipe network and achieve the purpose of safe maintenance.