CN1354262A

CN1354262A - Topside multiple blowing converter process

Info

Publication number: CN1354262A
Application number: CN 00133599
Authority: CN
Inventors: 樊永忠; 白瑞国; 张兴利; 刘伟
Original assignee: Chengde Iron & Steel Group Co Ltd
Current assignee: Chengde Iron & Steel Group Co Ltd
Priority date: 2000-11-16
Filing date: 2000-11-16
Publication date: 2002-06-19

Abstract

In the converter top-blowing oxygen-supplying process, said invention utilizes inert gas and spray gun arranged on the side surface of furnace body to stir melting bath of converter or powder-spray and stir, and provide inert gas for whole process. The described side-blowing gun is arranged on the side surface of converter, and placed on the position between the metting bath level and under the melting bath level to 500 mm. Its blowing direction is downward inclined at a certain angle and directing at bottom portion of melting bath. The place includes angle alpha of said blowing direction and bottom plane of melting bath bottom is 5-25 deg., and the blowing direction of side-blowing gun and the converter tangential passed through said side-blowing gun point can be formed a includes angle beta of 10-20 deg. Sad invention can improve stirring codition of melting bath, quicken various reaction speed and reduce oxygen content is molten steel and FeO in end slag.

Description

Topside multiple blowing converter process

The present invention belongs to steelmaking technical field for a kind of converter smelting method that adopts all gases side-blowns such as nitrogen, argon gas, carbon dioxide gas also to cooperate the top-bottom blowing of oxygen top blown in conjunction with the various pulvis of winding-up.

At present, domestic and international many steelworkss adopt the converter smelting technology of top bottom blowing.But because the bottom blowing rifle exists following problems to make it be difficult to be used widely, especially the suffered restriction of the application in middle-size and small-size converter is bigger.

1, the bottom blowing rifle easily stops up, and it is difficult recover to handle, thus work-ing life is low, can not be synchronous with lining life;

2, the bottom blowing rifle is made difficulty, and price is higher;

3, bottom blowing gun barrel internal diameter is little, and gas flow is restricted and is unstable, can not realize dusting, and its Controlling System complexity, maintenance difficulties is big.

Purpose of the present invention just provides a kind of Topside multiple blowing converter process.This method cooperates oxygen top blown with the side-blown of all gases such as nitrogen, argon gas, carbon dioxide gas, and the converter smelting method of the various pulvis that comprise sweetening agent, dephosphorizing agent, reductor, carburelant, concurrent heating agent, oxygenant etc. of can realizing jetting.

The present invention utilizes rare gas element, in converting process, blow side, converter molten pool is stirred or the stirring of dusting, improve the agitation condition in molten bath, accelerate the speed of various reactions, the evenly composition and the temperature of molten steel in the molten bath reduce oxygen level in the endpoint molten steel and (FeO) in the finishing slag simultaneously, thereby improve every index of converter steelmaking.

The object of the present invention is achieved like this:

In converter top-blow oxygen supply process, utilize rare gas element by being arranged in the lateral rifle that blows of shaft, converter molten pool is stirred or the stirring of dusting, omnidistance for indifferent gas, air pressure and gas flow are adjusted at any time according to arts demand in converting process.Described side-blown rifle is arranged in the converter side, and can singly prop up also can many, the also arranged vertical but many side-blown rifles can be arranged in parallel; The side-blown rifle is arranged in bath surface with down to the position between the 500mm, be preferably 200～500mm, its blowing direction is that downward-sloping certain angle points to the bottom, molten bath, itself and horizontal plane angle α are 5～25 °, the angle β that the tangential formation of the blowing direction of side-blown rifle and converter by this side-blown rifle loca is 10～20 °, i.e. side drift angle.

The diameter of described spray gun is decided according to the tonnage and the required blowing gas flow of converter.

Fig. 1 is the layout synoptic diagram of spray gun in converter.

Fig. 2 is the A-A diagram of Fig. 1.

Among the figure: 1-top blast rifle, 2-liquid level, the 3-rifle that blows side.

Described method is owing to adopt top blast to join the converter steel making method of side-blown, can add strong mixing to converter molten pool, accelerate the speed of various reactions, and composition and temperature in the further even molten bath, reduce the oxygen content in the metal and slag in the molten bath, thereby improved the condition of converter smelting; Since two side-jetting rifles have have a down dip, the lateral deviation angle, thereby the molten metal slag liquid in the molten bath is formed the whipped form of circulation rotating, deadband eliminating, can make the various reactions in the molten bath even, smelting process is more steadily carried out fast, can also effectively prevent the splash in the converting process simultaneously.

Described method compared with prior art has following advantage:

1, eliminated the variety of issue that exists under present oxygen top blown converter steel making or the top and bottom complex blowing steel-making condition, and adopting the side rifle to compare with end rifle to have gas to carry can be large, stirring capacity is strong, without the possibility that blows through, make the various reactions in the molten bath more steadily quick, thereby eliminated the splash in the converting process, improved the smelting condition of converter.

2, because various reactions are carried out evenly and rapidly, improved oxygen utilization rate, also can increase oxygen supply intensity, smelting speed is accelerated, to a certain extent, smelting cycle has been shortened.

3, adopt described method, can realize the various pulvis of jetting, can reduce the cost of converter smelting, and improved steel quality.

4, the present invention is applicable to the converter smelting process of various tonnages.

5, the side-blown device of the present invention's employing is simple and reliable, and less investment during faults such as side-blown rifle generation obstruction, can be handled outside stove under hot state, is suitable for execute-in-place.

6, the present invention can be applicable to converter steelmaking, vanadium extraction, carries chromium and similar smelting technology, and be used for vanadium extraction, have reacting balance when putting forward technologies such as chromium, speed is fast, oxidation ratio is high, iron-holder is low, of high grade in the slag, its simple to operate, less investment.

Embodiment:

Be used for 20 tons of converters of semi-steel making after the vanadium extraction, used top blast technology, the steel-making of top and bottom complex blowing technology originally, now change the multiple blow moulding in described method-top side, its concrete processing condition are as follows:

Cancellation bottom blowing rifle is respectively arranged a side-blown rifle nitrogen-blow at both sides gudgeon vertical line apart from the following 300mm of bath surface place; Former bottom blowing rifle injection diameter is 2.0mm, and the rifle injection diameter that now blows side is 20mm; Side-blown rifle injection direction is downward, with horizontal plane angle α be 10 °, the injection direction of side-blown rifle is 15 ° with the tangential angle β of converter by this side-blown rifle loca.Air pressure and gas flow are set set-point according to arts demand and are realized adjusting automatically in converting process.

Table 1 is the technical indicator contrast situation of three kinds of different injection methods

The technical indicator contrast of three kinds of different injection methods of table 1

Project	Nitrogen supply (NS) amount M ³/h	V slag grade %	The surplus vanadium % of half steel	Vanadium recovery %	TFe % in the slag	Smelting cycle min
Project	Nitrogen supply (NS) amount M ³/h	V slag grade %	The surplus vanadium % of half steel	Vanadium recovery %	TFe % in the slag	Smelting cycle min	The top blast vanadium extraction		??12.96	??0.059	??77	??36	??17.5
Top and bottom complex blowing	??80～120	??13.54	??0.037	??80.2	??33	??16	The top blast vanadium extraction		??12.96	??0.059	??77	??36	??17.5
Top and bottom complex blowing	??80～120	??13.54	??0.037	??80.2	??33	??16	Blow again the top side	??300～500	??14	??0.029	??80.5	??28	??14.5

Claims

1, a kind of Topside multiple blowing converter process, it is characterized in that in converter top-blow oxygen supply process, utilize rare gas element by being arranged in the lateral rifle that blows of shaft, converter molten pool is stirred or the stirring of dusting, omnidistance for indifferent gas, described side-blown rifle is arranged in the converter side, and can singly prop up also can many, the also arranged vertical but many side-blown rifles can be arranged in parallel; The side-blown rifle is arranged in bath surface with down to the position between the 500mm, its blowing direction is that downward-sloping certain angle points to the bottom, molten bath, itself and molten bath base plane angle α are 5～25 °, the angle β that the tangential formation of the blowing direction of side-blown rifle and converter by this side-blown rifle loca is 10～20 °.

2, the method for claim 1 is characterized in that described side-blown rifle is arranged in the following 200～500mm of bath surface.

3, the method for claim 1 is characterized in that described side-blown rifle is arranged in the following 300mm of bath surface.