摘要 |
Equipment for injecting pulverized coal and oxygen into a blast furnace from a blast furnace tuyere through a lance, wherein the mixing of gas inside the blast furnace into the oxygen piping that connects to the lance and the mixing of gas inside the blast furnace or oxygen into the nitrogen piping are prevented. The oxygen-injecting equipment (100) is provided with lances (4), oxygen piping (7) provided with oxygen shut-off valves (22), a flow rate adjustment valve (21), nitrogen piping (8) provided with nitrogen shut-off valves (28), and a control device (30) for opening and closing the oxygen shut-off valves (22) and nitrogen shut-off valves (28). The oxygen piping (7) is connected to the lances (4) and supplies oxygen (40) to the lances (4). The nitrogen piping (8) is connected to the oxygen piping (7) upstream of the oxygen flow rate adjustment valve (21) in the oxygen flow. The oxygen shut-off valves (22) are provided in the oxygen piping (7) upstream of the position where the oxygen piping (7) connects with the nitrogen piping (8) in the oxygen flow. The control device (30) closes the nitrogen shut-off valves (28) when the oxygen shut-off valves are open and opens the nitrogen shut-off valves (28) when the oxygen shut-off valves (22) are closed. |