Who has information on the Luchi three-stage furnace

A critical flow nozzle is a converging nozzle installed between two flanges, with the converging end facing downstream; its diameter is generally between 50 and 102 millimeters. Function of the critical nozzle: A certain amount of leakage at the bottom of the three-spinners is necessary to ensure good separation effects. The critical nozzle is used to control the flow rate of the flue gas flowing downstream through the three-spinning legs by about 3%-5%, in order to ensure the separation efficiency of the three spinners. Structure of the critical nozzle: a converging throat, similar to an orifice plate. Principle of the critical nozzle: As smoke flows through the nozzle, a pressure drop is generated. The flow rate of smoke passing through the nozzle increases as this pressure drop increases. However, when the pressure drop reaches a certain level, namely the critical pressure drop, the flow rate of smoke through the nozzle no longer increases, regardless of how much the pressure behind the nozzle decreases. The flow velocity at this point is the critical flow velocity of the smoke, which is roughly equivalent to the speed of sound under local conditions. In this way, it serves to limit the flow rate of smoke.

In a Luzzi furnace, as coal moves downward from the upper part of the furnace, it passes through three stages: the first is the drying stage； Next is the pre-distillation section ； Finally, there is the coke cooling section, which is why it is called the Lurgi three-stage furnace.