The invention provides a self-sealing
nitrogen circulating cooling method which comprises the following steps: a.
nitrogen discharged after
oxygen generation through the absorption
oxygen-generation technology in a steel
plant is delivered to a blower header
pipe through a pressure pump and a delivery pipeline, and the
nitrogen in the blower header
pipe is mixed with a recycle gas after
recovery of heat; b. after pressure is applied to the
mixed gas by a blast blower, the
mixed gas is delivered to an air inlet
pipe of a cooler, enters a material layer zone of a self-cooler through the air inlet pipe, and then is output through a large
flue after heat exchange with a high temperature
mass at the temperature of 1000 DEGC; and c. the temperature of
waste gas in the large
flue reaches up to 500-600 DEG C, and then is reduced to 180-230 DEG C after
recovery of heat, and the
waste gas is again led to the blower header pipe as a recycle gas for mixed cycle utilization with supplementary nitrogen. The technology can realize continuity, stability,
recovery of high temperature
waste gas and metallization rate of products in production, meet the national policy requirements for
energy conservation, emission reduction and cyclic economy, and provide space for reducing production cost.