The flue gas circulation technology is a new type of sintering mode developed based on the principle that part of the hot exhaust gas is reintroduced into the sintering process. It has significant effects on improving the utilization rate of sintering waste heat, reducing pollutant emissions and sintering energy consumption. However, the flow state of the circulating flue gas in the flue gas hood and the air leakage of the flue gas hood are very important to the effect and stability of the flue gas circulation. For this reason, a simulation of the flue gas flow and air leakage in the circulating flue gas hood of a steel plant showed that the existing flue gas hood manhole is opened to some extent, although the strength of the flue gas entering to form a vortex is weakened, but Does not improve the flue gas rotating flow, resulting in uneven flue gas flow rate on the material surface; by optimizing the structure and number of baffles in the flue gas hood, the flue gas rotating flow in the flue gas hood is weakened, and the circulation of the flue gas flow is significantly improved , So that the flue gas distribution is more uniform; at the same time, the air leakage of the flue gas hood is greatly improved. After optimization, the air leakage port on the A side is changed from the air leakage 1.2 m3·s-1 to the suction air 2.4 m3·s-1, which is conducive to the forward movement of the sintering production .