The invention relates to a device and method for top gas enrichment utilization of a
blast furnace, in particular to a device and method for using top gas in a
blast furnace production process, belonging to the field of
smelting pig iron with the
blast furnace. The device is characterized in that: a tee joint is arranged on a pipeline between a gas purifying and de-dusting
system and an excess pressure power generation device; a gas pressurization device, a gasification furnace and a gas back-eject hole which is formed on the blast furnace are connected through the pipeline and a valve to form one way of the tee joint; the gasification furnace is provided with an
oxygen supply pipeline and a
coal blending device; the enriched gas, after being pressurized, enters the gasification furnace and is subjected to gasification reaction with
oxygen and
powder coal in the pressurized gasification furnace; a
reaction product is ejected into the blast furnace for
smelting iron through the back-eject hole which is formed on the blast furnace; the excess pressure power generation device is respectively connected with a
hot blast heater, a power
plant boiler pipeline and a valve through a gas
distributor to form another way of the tee joint; and the generated hot air is fed into the blast furnace through a
nozzle. The device has the advantages of novel conception, simple process flow, easiness in implementation, safety and reliability in operation and capabilities of increasing the calorific value of gas, ejecting back to smelt iron, increasing the indirect
reduction rate, reducing the
coal ratio, reducing blast furnace
slag and CO2 emission, regulating and controlling the width of a cohesive zone of the blast furnace, ensuring long-term smooth running of the blast furnace, avoiding
diffusion of the top gas, saving energy and contributing to environment friendliness.