Denitrification technology process of direct fired furnace sintering machine in steel plant
Layout position of direct fired furnace
The entire sintering flue gas denitrification system adopts:
The entire sintering flue gas denitrification system adopts: medium high temperature SCR denitrification device+flue gas heat exchange device (GGH)+direct combustion furnace heating. The direct combustion furnace is arranged in the U-shaped flue, located in front of the ammonia spray grille.
Internal System Description of Direct Combustion Furnace
A direct fired furnace consists of three parts: a combustion system, a flue gas system, and a control system:
1. The combustion system consists of a burner, a combustion air system, a gas supply system, and an ignition system.
A burner: Two burners are set up in a staggered arrangement in the flue gas duct to facilitate uniform mixing of heated flue gas (facilitating uniform thermal expansion of the flue gas duct and uniform inlet temperature of SCR);
B Combustion air system: Under normal circumstances, flue gas is used as the combustion air,
In the fault state, switch to air assisted combustion;
C ignition system: using plasma ignition; Out of the world
2. The flue gas system consists of a flue gas diversion device, a combustion chamber, and a mixing chamber. The flue gas is divided into three streams by the diversion device, and two streams on both sides flow through the combustion chamber from the outside for preheating. Afterwards, it mixes with a stream of smoke in the middle and the high-temperature smoke generated by combustion in the mixing chamber at the rear;
3. The control system mainly includes: control of fuel gas, control of combustion air, control of outlet temperature of direct fired furnace, and safety interlock.
