GAS-REGULATING SYSTEM FOR BLAST FURNACE Russian patent published in 1998 - IPC

FIELD: ferrous metallurgy, in particular, blast-furnace operation; may be used in injection of natural gas into air tuyeres of blast furnaces. SUBSTANCE: injected into air tuyeres is homogeneous mixture of natural gas with oxygen in preset ratio. Homogeneous mixture is prepared in gas-regulating system having pipelines supplying natural gas, inert gas and oxygen; bypass pipeline; distributing header with pipeline for supplying gas to air tuyeres and mixer. Pipelines are provided with cutoff, safety and measuring and regulating apparatuses. Mixer is cut in pipeline of natural gas before header. Bypass pipeline is connected to natural gas pipeline before and after the mixer which is made in the form of cylindrical chamber with its diameter-to-length ratio equalling 0.4-0.7. Cut in mixer chamber square to its axis is perforated pipe with plugged end connected with pipeline supplying oxygen. Diameter of perforated pipe equals 0.15-0.5 diameter of mixer chamber. Total area of holes on perforated pipe amounts to 0.3-0.6 area of its flow section, and diameter of holes amounts to 0.03-0.7 of pipe diameter. Supply of natural gas in composition of homogeneous mixture with oxygen ensures thorough burning of gas due to intensification of burning and reduces fuel consumption in blast furnace. EFFECT: provision of thorough burning of natural gas in blast furnaces; reduced consumption of coke. 6 cl, 2 dwg