Control method for preventing explosion venting of dry dedusting system in converter smelting process

Abstract

The invention discloses a control method for preventing explosion venting of a dry dedusting system in converter smelting process. The control method includes the steps of: firstly adding steel scraps into a converter, and then feeding molten iron into the converter; supplying oxygen to the liquid surface of the molten iron from the top through a oxygen lance, feeding stirring gas into the molten iron from the bottom to dephosphorizing the molten iron, at the same time controlling the oxygen supply intensity at all periods of time, and purging a flue of the converter for 90seconds through nitrogen 30seconds before the dephosphorization process is finished; bringing up the oxygen lance after the dephosphorization process is finished and conducting rapid deslagging operation to the converter; and decarbonizing the molten iron, bringing up the oxygen lance after the decarbonization process is finished, and then tapping of molten steel is carried out. According to the invention, in the method, the nitrogen purging time is set through a PLC(Programmable Logic Controller) program, the opening degree of an oxygen flow valve of the converter is set to be 40% and the oxygen release point of the oxygen lance of the converter is set to be 13.73m. Therefore, the problem of ignition delay upon release of oxygen is solved and the problem that explosive gas mixture is easy to produce in the dephosphorization process after the oxygen lance is brought up is avoided. The control method is simple and effective and is low in cost.

Description

technical field [0001] The invention belongs to the technical field of converter steelmaking, and in particular relates to a control method for preventing explosion venting of a dry dust removal system during the converter smelting process. Background technique [0002] SGRP (Slag-less Generation Refining Process) divides converter blowing into two stages: dephosphorization (including desiliconization) and decarburization. The slag (30-70%) is poured out, followed by a second stage of decarburization blowing. [0003] SGRP is a low-cost converter smelting process characterized by low consumption of auxiliary raw materials and small amount of slag. In order to better carry out SGRP process smelting, reduce lime consumption, reduce the amount of converter slag and complete the task of cost reduction, Shougang No. Equipped with dry dust removal system. In May 2012, the proportion of SGRP smelting furnaces reached 78.27%. [0004] The Chinese invention patent application wit...

AI Technical Summary

Problems solved by technology

[0006] The technical problem to be solved by the present invention is to provide a control method for preventing explosion venting of the dry dedusting system during the converter smelting process, which can not only solve the problem of ignition delay of blowing, but also avoid the formation of explosive mixed gas after the gun is lifted in the dephosphorization stage The problem