Double-control blowing-out method for large blast furnace

Abstract

The invention discloses a double-control blowing-out method for a large blast furnace, which belongs to the technical field of metallurgy and comprises the following steps: 1, two sets of atomization water fetching systems are arranged at the top of a pre-blowing-down furnace, one set of atomization water fetching system accounts for one third of the required water fetching amount per hour, and the other set of atomization water fetching system accounts for two thirds of the required water fetching amount per hour; 2, loading wet coke with saturated water quantity into a coke bin before charging stoppage of the furnace charge, and pressing the top temperature by using the saturated wet coke after the top temperature cannot be effectively controlled by water fetching at the furnace top along with proceeding of a stockline; 3, the air volume is controlled to be full air in the early stage, the oxygen enrichment rate is 3.0%-4.0%, and the air volume is controlled to be 80% or above of the full air in the later stage; 4, zero-interval tapping is carried out, the iron notch depth is guaranteed, and iron in the whole furnace flows out of the iron notch to the maximum extent; and 5, blast furnace gas full grid-connected recovery. The problems that a large amount of water is fetched into the furnace during blowing out of an empty stockline, water gas detonation occurs in the furnace, the furnace wall collapses, the task of removing the interior of the furnace during blowing out of a filling method is heavy, and a large amount of manpower, material resources and time are consumed can be solved.

Description

technical field [0001] The invention belongs to the technical field of metallurgy, and in particular relates to a double-control shutdown method for a large blast furnace. Background technique [0002] As we all know, when the production of blast furnace reaches a certain number of years, medium repair or overhaul is required. Shutting down a blast furnace is a relatively dangerous operation, and the key point is to do a good job of shutting down preparations and safety measures to ensure a safe and smooth shutdown. The empty material line method means that no material is charged into the furnace during the shutdown process, and the temperature of the furnace top is controlled by pumping water from the top of the furnace, and the wind is stopped when the material level drops to the vicinity of the tuyere. Its advantage is that after the furnace is shut down, the removal amount in the furnace is reduced, and the shutdown process is accelerated, which buys time for major and ...

AI Technical Summary

Problems solved by technology

[0003] In order to solve the technical problems existing in the known technology, the present invention provides a large-scale blast furnace double-control shutdown method, which overcomes the existing method of stopping the hollow material line to pump a large amount of water into the furnace, causing water gas detonation and furnace wall collapse in the furnace The danger of the filling method, as well as the heavy cleaning task in the shutdown of the filling method, consumes a lot of manpower, material resources and time.