CN214270950U

CN214270950U - LF stove is concise blows slag face deoxidation device

Info

Publication number: CN214270950U
Application number: CN202120214366.4U
Authority: CN
Inventors: 梁佰战; 郑力宁; 唐宁; 蒋栋初; 陈刚祥; 王子健
Original assignee: Jiangsu Lihuai Steel Co ltd; Jiangsu Shagang Group Huaigang Special Steel Co Ltd
Current assignee: Jiangsu Lihuai Steel Co ltd; Jiangsu Shagang Group Huaigang Special Steel Co Ltd
Priority date: 2021-01-26
Filing date: 2021-01-26
Publication date: 2021-09-24
Anticipated expiration: 2031-01-26

Abstract

The utility model discloses a concise jetting slag face deoxidation device of LF stove, including big feed bin, big feed bin upper end is connected and is used for carrying the material mouth in the big feed bin with the deoxidier, the valve is connected to big feed bin lower extreme, the feed bin is connected to the valve, weighing device is connected to the feed bin, deoxidier transmission pipeline is connected to weighing device, the spray gun is connected to deoxidier transmission pipeline, be equipped with the bell wicket on the bell of LF stove, the axial that the spray gun stretched into LF stove and spray gun from the bell wicket is perpendicular with the slag interface, and parallel with the electrode in the LF stove, still including the spray gun operating system who is used for controlling the spray gun lift, the nozzle head of spray gun includes the inner tube, the outer tube, have the air inlet with the cavity intercommunication on the outer tube, the gas outlet, air inlet intercommunication air supply, still be provided with the blowout mouth on the spray gun, blowout mouth intercommunication gas outlet. The accuracy and the effectiveness of the refining and deoxidation of the existing LF furnace are improved, the labor intensity of workers in the LF refining process is reduced, and the in-plant environment in the LF refining and deoxidation process is improved.

Description

LF stove is concise blows slag face deoxidation device

Technical Field

The utility model relates to a metallurgical machinery device field, concretely relates to concise jetting slag face deoxidation device of LF stove.

Background

Regardless of long flow or short flow, the refining process of the LF furnace plays a very important role in the whole steelmaking process, and plays key roles of fine adjustment of chemical components, temperature, deoxidation, desulfurization, inclusion removal and the like, and the quality of the process control is directly related to the smoothness of the next process, the purity of molten steel and the like. At present, the deoxidation method in most steel plant LF furnaces is mainly slag surface diffusion deoxidation, the slag surface deoxidizer is mainly powdery or granular (calcium carbide, aluminum particles, silicon carbide and the like), the adding mode of the slag surface deoxidizer is mainly manual or two types of material bins, the slag surface deoxidizer is manually added and is added by using a shovel in a scattered mode or in a whole bag mode, the labor intensity of workers is high, the workers are dangerous, meanwhile, when the materials are added at every time, the workers need to stop electrifying and then open a furnace door, the phenomenon that part of smoke in the furnaces overflows out of the furnaces to pollute the environment can be caused, and meanwhile, the production efficiency is also reduced. The manual addition of the slag surface deoxidizer also has the defects that the position of the deoxidizer added into the furnace is inaccurate, and the added deoxidizer cannot play a role in deoxidation. The deoxidizers are added manually and in the storage bin to form piles to appear on the slag surface and float on the slag surface, so that the deoxidizers are not beneficial to deoxidizing the slag surface and even cannot play a role in deoxidizing. How to simply and efficiently add the slag surface deoxidizer into the refining furnace becomes a difficult problem which troubles a plurality of steel mills. Some bold attempts are also made in the steel mills, and some utility model patents are also applied. For example, patent publication No. CN204455190U discloses a utility model of a deoxidizer adding device for an LF refining furnace and an LF refining furnace, which uses gas to blow the deoxidizer onto the slag surface to realize deoxidation of the slag surface. Because the spraying port is positioned on the furnace wall on one side of the LF furnace, the deoxidizer is easy to be sprayed outside the LF furnace from the opposite side of the LF furnace when the deoxidizer is improperly sprayed in the spraying process; in the conventional refining process, dust removal equipment of the refining furnace is opened, and the feeding mode is very easy to suck away by the dust removal equipment when some powdery deoxidizers are blown and scattered; because the deoxidizer is blown and scattered on the slag surface, the deoxidizer can be combined with oxygen in the air, so that the deoxidizer loses the deoxidizing effect. The patent of publication No. CN205676501U discloses an automatic adding device of powdery deoxidizer of LF refining furnace, the utility model discloses a spray gun is installed on the furnace cover to this utility model patent use, can see from the patent spray gun structure that there are some regions in the jetting process and can't be blown to, for some large-scale refining furnaces, this kind of unevenness of jetting can be more serious, the inside water that uses of this spray gun is as the coolant simultaneously, this has just increased the use risk for this nozzle in the use, the cooling water in the spray gun probably flows into the stove promptly to arouse the explosion or increase the hydrogen content in the molten steel. At present, the refining furnace has more types, some are powdery, and some are granular, but the refining furnace is only applicable to the powdery state, so that the application range of the refining furnace is limited; patent publication No. CN202626233U discloses an LF refining device with powder spraying function, which uses a hollow electrode on an LF furnace, each hollow electrode is used as a spraying tube for spraying a desulfurizer and the like, although the patent has the advantage that the spraying tube is not additionally added, dynamic friction is generated between the desulfurizer, alloy powder and the like and the inner wall of the hollow electrode in the spraying process, and the dynamic friction causes the internal abrasion of the electrode, so that the electrode is continuously consumed and even scrapped; the interaction between blowing and electrifying also has the influence which is not beneficial to refining; in the normal refining process, the distance between the electrode and the steel slag is short, the injected material is extremely easily added into the molten steel due to improper injection, the injection area is fixed, and the blind area is formed in an individual area. In the refining process of the LF furnace, the research on the adding mode of the deoxidizer is bound to become a new research hotspot of the refining process in the aspect of improving the utilization rate of the existing deoxidizer.

SUMMERY OF THE UTILITY MODEL

In order to improve the accuracy and the validity of the refining deoxidation of the existing LF furnace, lighten the labor intensity of workers of the LF refining process, improve the in-plant environment of the LF refining deoxidation process and the like, the utility model provides a refining blowing slag surface deoxidation device of the LF furnace.

The utility model discloses a technical scheme as follows: a slag surface deoxidizing device for LF furnace refining blowing comprises a large storage bin, wherein the upper end of the large storage bin is connected with a material port for conveying deoxidizing agents into the large storage bin, the lower end of the large storage bin is connected with a valve, the valve is connected with the storage bin, the storage bin is connected with a weighing device, the weighing device is connected with a deoxidizing agent conveying pipeline, the deoxidizing agent conveying pipeline is connected with a spray gun,

a furnace cover small door is arranged on a furnace cover of the LF furnace, when the furnace cover small door is opened for blowing, a spray gun extends into the LF furnace from the furnace cover small door, the axial direction of the spray gun is vertical to a steel slag interface and is parallel to an electrode in the LF furnace,

also comprises a spray gun lifting system used for controlling the lifting of the spray gun,

wherein the content of the first and second substances,

the nozzle head of the spray gun comprises an inner pipe and an outer pipe, a cavity is formed between the inner pipe and the outer pipe, the outer pipe is provided with an air inlet and an air outlet which are communicated with the cavity, the air inlet is communicated with an argon source,

the spray gun is also provided with a blowing opening which is communicated with the inner cavity of the inner tube, and the blowing opening is communicated with the air outlet.

On the basis of the scheme, preferably, the deoxidizer in the storage bin is conveyed into the spray gun through a conveying belt in a conveying pipeline.

On the basis of the scheme, as the optimization, a protective gas inlet is arranged on the large material bin and is connected with a protective gas source.

On the basis of the above scheme, preferably, there are 3 spray guns, and there are 3 furnace cover wicket gates.

On the basis of the scheme, preferably, the furnace cover small doors are uniformly distributed in the circumferential direction of the furnace cover.

Compared with the prior art, the utility model discloses following beneficial effect has:

1. the utility model discloses an use the argon gas that steel mill is commonly used as spray gun coolant rather than water, this has solved water-cooling with regard to fundamentally and has brought some potential safety hazards. The special structure of the nozzle of the spray gun can preheat the entering cooling argon and use the preheated argon as the blowing gas.

2. The novel use patent uses a special structure spray gun with an additional lifting system, the spray gun can be lowered to a required position in the furnace according to the type of the deoxidizer, the spray gun is arranged near the argon stirring position, and the spray gun is forbidden to be arranged right above the argon stirring position and close to the furnace wall or an electrode; the spray gun with a special structure can effectively protect the electrode and avoid the erosion of the electrode and the furnace wall by the blown deoxidizer, so that the deoxidizer can be better blown to the slag surface to a certain depth to participate in the deoxidation of the slag surface; the method not only improves the effect of the slag surface deoxidizer, but also reduces the waste of the deoxidizer to a certain extent, in particular to a powdery deoxidizer, and greatly improves the environmental pollution caused by the overflow of the deoxidizer outside the furnace.

3. The novel deoxidizer can use several common deoxidizers, has simple structure and easily understood principle, and can be widely used in various steel mills.

Drawings

Fig. 1 is a schematic sectional view of the present invention;

FIG. 2 is a top view of a furnace cover of the LF furnace;

FIG. 3 is a schematic view of a spray gun;

FIG. 4 is a schematic cross-sectional view of a spray gun.

In the figure: 1-furnace cover, 2-spray gun, 3-furnace cover small door, 4-spray gun lifting system, 5-material opening, 6-protective gas inlet, 7-large storage bin, 8-valve, 9-storage bin, 10-weighing device, 11-deoxidizer conveying pipeline, 12-electrode, 13-gas inlet, 14-gas outlet, 15-spray nozzle, 16-outer tube and 17-inner tube.

Detailed Description

In order to more clearly illustrate embodiments of the present invention or technical solutions in the prior art, specific embodiments of the present invention will be described below with reference to the accompanying drawings. It is obvious that the drawings in the following description are only examples of the invention, and that for a person skilled in the art, other drawings and embodiments can be obtained from these drawings without inventive effort.

As shown in figures 1-4, a slag surface deoxidizing device for LF furnace refining blowing comprises a large material bin 7, wherein the upper end of the large material bin is connected with a material port 5 for conveying deoxidizing agent into the large material bin, the lower end of the large material bin is connected with a valve 8, the valve is connected with the material bin 9, the material bin 9 is connected with a weighing device 10, the weighing device is connected with a deoxidizing agent conveying pipeline 11, the deoxidizing agent conveying pipeline is connected with a spray gun 2,

a furnace cover 1 of the LF furnace is provided with a furnace cover small door 3, when the furnace cover small door is opened for blowing, a spray gun extends into the LF furnace from the furnace cover small door, the axial direction of the spray gun is vertical to a steel slag interface and is parallel to an electrode 12 in the LF furnace,

a lance lifting system 4 for controlling the lifting of the lance is also included,

wherein the content of the first and second substances,

the nozzle head of the spray gun comprises an inner pipe 17 and an outer pipe 16, an independent cavity is formed between the inner pipe and the outer pipe, the outer pipe is provided with an air inlet and an air outlet which are communicated with the cavity, the air inlet is communicated with an argon source,

Wherein, the spray gun is installed on the bell at least 3 and above, distribute evenly in the refining furnace circumferentially, in the utility model's figure, take 3 as an example, its quantity and position of concrete installation can be arranged according to the size and ladle shape of refining furnace; the special spray gun structure can effectively protect the electrode in the refining furnace and prevent the electrode from being washed by the blown deoxidizer; the lance is placed in the vicinity of the argon gas stirring, and is prohibited from being placed directly above the argon gas stirring position and in close proximity to the furnace wall or the electrode. The deoxidizer enters a bin from a large bin with gas protection, a certain amount of deoxidizer is weighed by a weighing device according to the deoxidation requirement, and the deoxidizer is conveyed into a spray gun with blowing gas through a deoxidizer conveying pipeline; before the deoxidizer is weighed, according to the deoxidizer category (aluminum particle deoxidizer, non-aluminum particle deoxidizer and powdery deoxidizer), the lifting system lowers the spray gun to a proper position in the furnace, meanwhile, the small flow of the sprayed gas flows in the spray gun, at the moment, the gas in the spray gun and the inner wall of the nozzle of the spray gun are preheated by heat exchange, when the deoxidizer is about to be added into the spray gun, the flow and the pressure of the sprayed gas reach specific values, and the deoxidizer entering the spray gun is sprayed to a certain depth of a preset area of the steel slag to participate in slag surface deoxidation. The utility model uses a specific spray gun structure, argon gas commonly used for steel making is selected as a spray gun cooling medium, a series of potential safety hazards caused by water cooling are solved, the argon gas as the cooling medium is preheated in the special spray gun structure, and the temperature drop of the slag surface caused by cold argon gas injection is reduced; the special spray gun structure and the control of different spray gun blowing positions and strength also greatly improve the slag surface diffusion deoxidation effect and reduce the waste of the deoxidizer.

When the device is used specifically, a deoxidizing agent is added into a large bin 7 from a material port 5, for example, when calcium carbide deoxidizing and powdery deoxidizing agents are blown, nitrogen gas or other inert gases is firstly introduced into the large bin and the bin from a protective gas inlet on the large bin before the deoxidizing agent is added into the bin, at the moment, a valve is in an open state, so that air and water vapor in the two bins can be conveniently discharged, a certain amount of nitrogen gas is kept in the two bins, the other deoxidizing agents do not need to be introduced, and according to the blowing of common three types of deoxidizing agents (aluminum particles, granular deoxidizing agents without aluminum particles and powdery deoxidizing agents), the blowing mode is set to be three (the height of a spray gun is reduced, the pressure and the flow of blowing; the valve 8 is used for controlling the material transmission from the large storage bin to the storage bin, the storage bin 9 is provided with a weighing system, the weight of the deoxidizer in the storage bin 9 can be accurately metered and controlled, the deoxidizer amount in each spray gun can be controlled according to different positions of the three spray guns in the furnace by a set control program, the deoxidizer amount is weighed by three weighing devices 10, the weighed deoxidizer is sent to the three spray guns 2 through transmission belts in three deoxidizer transmission pipelines 11, after the deoxidizer signal is weighed, furnace cover small doors 3 at corresponding positions of the three spray guns are opened, then the three spray gun lifting systems 4 lower the three spray guns 2 to proper positions in the furnace, spray gun nozzles are heated after entering an LF furnace, argon of an argon gas source is introduced into the spray guns 2 through an air inlet 13, the argon is used as a coolant of the spray gun nozzles on one hand, on the other hand, heat exchange is carried out between the argon and the nozzle walls to be preheated, argon is circularly preheated in the spray gun, and the preheated argon is discharged from the gas outlet 14 and is distributed to three spray nozzles 15 of the spray gun; after the deoxidizer enters the spray gun to send out a signal, the argon input flow is rapidly increased, and the three spray guns 2 spray the deoxidizer entering the three spray guns to the LF furnace steel slag to a certain depth to participate in slag surface deoxidation. After the deoxidizer is blown, the argon flow is rapidly adjusted to be small flow, meanwhile, the three spray guns 2 are rapidly lifted to the initial position by the lifting system 4, and meanwhile, the furnace cover small door 3 is closed and the argon is closed.

It should be noted that the above embodiments can be freely combined as necessary. The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A slag surface deoxidizing device for LF furnace refining blowing is characterized by comprising a large storage bin (7), wherein the upper end of the large storage bin is connected with a material port (5) used for conveying deoxidizing agent into the large storage bin, the lower end of the large storage bin is connected with a valve (8), the valve is connected with the storage bin (9), the storage bin (9) is connected with a weighing device (10), the weighing device is connected with a deoxidizing agent conveying pipeline (11), the deoxidizing agent conveying pipeline is connected with a spray gun (2),

a furnace cover small door (3) is arranged on a furnace cover (1) of the LF furnace, when the furnace cover small door is opened for blowing, a spray gun extends into the LF furnace from the furnace cover small door, the axial direction of the spray gun is vertical to a steel slag interface and is parallel to an electrode (12) in the LF furnace,

also comprises a spray gun lifting system (4) for controlling the lifting of the spray gun,

wherein the content of the first and second substances,

the nozzle head of the spray gun comprises an inner pipe (17) and an outer pipe (16), a cavity is formed between the inner pipe and the outer pipe, the outer pipe is provided with an air inlet and an air outlet which are communicated with the cavity, the air inlet is communicated with an argon source,

2. The device for deoxidizing slag surface in LF furnace refining blowing of claim 1, wherein the deoxidizer in the storage bin is conveyed into the spray gun through a conveying belt in a conveying pipeline.

3. The LF furnace refining blowing slag surface deoxidizing device as set forth in claim 1, wherein the large bunker is provided with a shielding gas inlet, and the shielding gas inlet is connected with a shielding gas source.

4. The LF furnace refining blowing slag surface deoxidation apparatus as claimed in claim 1, wherein there are 3 lances, and 3 furnace lid wicket gates.

5. The LF furnace refining blowing slag surface deoxidation device as claimed in claim 4, wherein the small furnace cover doors are evenly distributed on the circumferential direction of the furnace cover.