The domestic ladle roaster has gone through a series of development processes from using only one gas pipe to using ordinary burners, high-speed burners, hot-air burners, self-preheating burners and regenerative burners

Most of the domestic steelmaking plants built in the 1950s and 1960s did not have ladle baking equipment or only inserted a gas pipe into the ladle for baking. Due to the low ladle baking temperature, high tapping temperature, low furnace life and long smelting time, the output of steel is limited and the cost is increased

During the "Seventh Five-Year Plan" period, the Ministry of Metallurgy proposed to promote new devices and new technologies for ladle baking, which has greatly improved the level of ladle baking in China. Most enterprises have changed the baking process of using only gas instead of air in the past, and accordingly, gas and oil ladle baking devices have emerged. The burner types include injection burner and sleeve burner, and the ladle cover is added on the ladle to reduce heat loss. Because the flame kinetic energy of the ladle burner is small, the temperature distribution of the ladle is uneven, the baking time is long, and the fuel consumption is large

High-speed burner is one of the new technologies that have made breakthroughs in modern thermal technology. Its characteristic is that the combustion gas outlet speed can reach 100~300m/s. When heating objects, its heating effect is much better than that of ordinary burners in terms of heating speed and heating uniformity. Due to the high outlet speed of the high-speed burner, the refractory consumption of the ladle baking burner is large, and the service life is low. The site environment of the ladle baking equipment in the general steel plant is relatively poor, which is not suitable for installing precise control equipment. Therefore, the equipment development plant of Anshan Thermal Energy Research Institute has developed a simple high-speed burner for ladle baking, which basically maintains the characteristics of high airflow speed, fast heating and uniform temperature distribution of the ladle. Subsequently, oxygen-enriched burner and oil-gas dual-purpose burner were developed to meet the needs of steelmaking plants with only blast furnace gas or converter gas and low gas calorific value or insufficient gas volume

In order to further reduce energy consumption, the ladle baking device that preheat air or gas with flue gas came into being. There are two types of structure: one is the separate type of burner and heat exchanger, and the other is the self-preheating type of burner. As air or gas is preheated, the theoretical combustion temperature of the flame is increased, the fuel consumption can be reduced, and the characteristics of large flame kinetic energy and uniform heating of the high-speed burner are maintained. Regenerative ladle roasters are increasingly being used In order to give full play to the role of ladle baking burner, the design and material selection of ladle cover can not be ignored. The ceramic fiber felt is used inside the ladle cover, and the polycrystalline mullite is used outside as the thermal insulation layer, which reduces the heat storage capacity of the ladle cover, reduces the heat loss, reduces the weight of the ladle cover, and extends the service life of the ladle cover< br/>