| 摘要 |
PURPOSE:To perform titled blowing while preventing clogging of a blow nozzle and conduit by a powder and granular material by releasing a conveying gas to the outside of a route via a gas separator provided in the route between a blow tank and a lance and controlling the pressure or/and blow rate of the conveying gas. CONSTITUTION:A lance 9 is stopped right above a molten iron 18 by a lifting device 10 for said lance. The gas controlled to the gaseous pressure and flow rate meeting the conveyance of a powder and granular material 2 having a low pressure range (<10atom and having large specific gravity) is blown through a lance nozzle 11 by opening an automatic valve 5 through a conveying gas piping 4 so as to prevent deposition of the material 12 in a conduit 6. A valve 3 for feeding out powder is then opened to pass the material 2 and conveying 6 the same to a gas separator 7. The excess conveying gas is separated and discharged piping 12, a discharge rate controller 13, a discharge flowmeter 14, etc. As a result, the material 2 mixed with the gas in the conduit 6 is increased in concn. and while the mixture is blown out of the nozzle 11 of the lance 9 through a flexible pipe 8, the lance is immediately immersed into the desired depth of the molten iron 8 to blow the mixture to the molten iron. The molten iron 18 is thus subjected to treatments such as desiliconization, dephosphorization, desulfurization, etc. |
