Scrap preheating process in steel production plants, comprises guiding furnace exhaust gas from melting unit into preheater, which flows through scrap column and preheats the furnace exhaust gas by guidable heat of the furnace exhaust gas

摘要

The scrap preheating process in steel production plants, comprises guiding furnace exhaust gas (2) from a melting unit (1) into a preheater (3), which flows through a scrap column (10) and preheats the furnace exhaust gas by guidable heat of the furnace exhaust gas, evacuating the preheated exhaust gas from the preheater over an exhaust gas channel (7) and into an exhaust gas treatment plant (13), in which the preheated exhaust gas is chemically/thermally treated and again guided. The preheated exhaust gas after evacuation is supplied without thermal post treatment in post-combustion chamber. The scrap preheating process in steel production plants, comprises guiding furnace exhaust gas (2) from a melting unit (1) into a preheater (3), which flows through a scrap column (10) and preheats the furnace exhaust gas by guidable heat of the furnace exhaust gas, evacuating the preheated exhaust gas from the preheater over an exhaust gas channel (7) and into an exhaust gas treatment plant (13), in which the preheated exhaust gas is chemically or thermally treated and again guided. The preheated exhaust gas after evacuating the preheater is supplied without thermal post treatment in a post-combustion chamber of a reaction- and separation chamber, in which the preheated exhaust gas is chemically treated and a large-grain dust separation takes place. A combined scrap preheating process in the preheater includes guiding the scrap preheating processes into the entire scrap column without a temperature fall under 800[deg] C, and externally supplying heat into the preheater through a burner system such as gas-oxygen-burner system. The external heat supply takes place in staggered form dependent of the temperature in the scrap column. The external heat supply in the staggered form is controlled by a temperature measuring system. The burner system is non-stoichiometrically driven with oxygen surplus to begin the scrap preheating process with maximum effort. After reaching a temperature of above 850[deg] C in the entire scrap column, the burner system is separately controlled over the temperature measuring system or the burner system is controlled over a time program. The low-pollution and high-temperature preheated exhaust gas is supplied to a heat exchanger through a cooler after the reaction- and separation chamber without rapid cooling. An independent claim is included for a device for carrying out a scrap preheating process in steel production plants.