RU69068U1 - COMPLEX FOR Smelting Cast Iron from Titanium-Containing Agglomerate and Pellets of Different Bases - Google Patents

Abstract

The utility model relates to ferrous metallurgy, and in particular to a complex of equipment for mixing and loading sinter and pellets into blast furnaces equipped with a cone-less loading device. The technical result achieved using the proposed mixing system is to improve the performance of the blast furnace during the melting of titanium-containing raw materials by mixing agglomerate and pellets. The technical result is achieved by the fact that the mixing system of sinter and pellets of a blast furnace for the production of cast iron from titanium-containing iron ore raw materials, including a blast furnace, a loading system for iron ore materials, coke and additives, a feed system for combined blasting, a system for removing blast furnace gas (and a system for cleaning melting products, additionally includes a system for mixing agglomerate and pellets Mixing agglomerate and pellets is achieved by coordinating the operating time of weighing devices. mixing reflected in reduced chemical composition of the fusion products oscillations.

Description

The proposed utility model relates to the field of ferrous metallurgy, in particular to the loading of agglomerate and pellets of different basicities into a blast furnace equipped with a cone-less loading device.

Many different loading devices are known for loading materials into the mines of blast furnaces. To evenly distribute the feed material over the mine cross section, decades ago rotary charge platforms with rotary distributors located eccentrically relative to the axis of the furnace were proposed. In such a device, due to the passage of the loading opening of the distributor over the shaft cross section along two circular trajectories superimposed on each other, a fairly uniform distribution of the loaded material is achieved without the formation of noticeable cone clusters [1].

A slightly different solution is known from the German patent document. The main elements of the loading devices are the first funnel with a discharge outlet in the form of a trunk for feeding material to the edge of the furnace and the second funnel with a vertical outlet for feeding material to the central part of the furnace [2].

Such a device is characterized by high cost and cumbersomeness, in addition, it is very limited in terms of achieving the desired distribution profile of various downloadable materials.

Known boot device blast furnace containing a receiving funnel with dividers, located one below the other and suspended on the rods cones with bowls. An additional truncated cone with four charge dividers and four conical cavities uniformly located on its surface is placed under the receiving funnel. The rod of the upper cone contains an extension that is positioned so that when the upper cone is closed, it is located in the outlet of the receiving funnel, and when the upper cone is lowered, under its outlet [3].

The disadvantage of this boot device is its bulkiness and complexity in maintenance, and also requires regular replacement due to exposure to high temperature and dust.

A disadvantage of the known boot devices is significant quantitative (by weight) and qualitative (by small fractions) unevennesses, which amount to 3-10%.

Moreover, even a relatively low unevenness always remains and over time leads not only to an increase in the circumferential unevenness of the gas flow, but also to a change in the thickness of the skull along the circumference of the shoulders and the hearth.

A known system for mixing agglomerate and pellets and the loading of titanomagnetite raw materials into a blast furnace equipped with a cone-less loading device, the operation of which is regulated by the technological instruction [4, Temporary technological instruction “Iron production”, VTI 102-D-130-2004, JSC “Nizhny Tagil Metallurgical Plant” , N-Tagil, 2004]. The system provides for separate loading of agglomerate and pellets in a blast furnace.

The disadvantage of the analogue is that in the process of separate loading of agglomerate and pellets into the blast furnace during their movement in the furnace volume, the pellets periodically enter the slag formation zone earlier than the agglomerate of the same portion. In this case, there is a change in the properties of primary slag and increased fluctuations in the chemical composition of the smelting products.

The technical result achieved using the proposed complex, shown in the figure, is the improvement of the blast furnace performance during melting of titanium-containing raw materials by reducing the proportion of titanium carbides and carbonitrides in the melting products.

The technical result is achieved by the fact that the blast furnace complex for the production of pig iron from sinter and pellets of different basicities, including a blast furnace, a dosing system for sinter, pellets, coke and additives, a material loading system in a blast furnace, a combined blast supply system, a blast furnace gas removal system and smelter cleaning system, contains

additionally a system for mixing agglomerate and pellets before loading them into a blast furnace.

Figure 1 shows the blast furnace complex for the production of cast iron.

The complex for smelting cast iron from titanium-containing sinter and pellets of different basicities consists of a blast furnace (1), a dosing system for sinter, pellets, coke and various additives (2), a material loading system (4) in a blast furnace, a combined blast feed system (5 ), flue gas removal systems (6), melting product cleaning systems (7) and agglomerate and pellet mixing systems (3) before loading into a blast furnace (1).

The charge feeding system is shown in Fig. 2.

Symbols adopted in Figure 2:

1 - coke hopper; 2 - limestone hopper; 3 - pellet hopper; 4 - hopper additives;

5 - agglomerate hopper; 6 - coke feeder; 7 - coke rumble;

8 - scales bunker pellets (O ₁ , O ₂ ); 9, 11 - feeder; 10 - slide gate;

12 - the roar of the agglomerate (A _1, A ₂ , A ₃ , A ₄ ); 13 - scales bunker coke; 14 - switch flow of iron ore materials; 15 - conveyor belt;

16 - scales bunker iron ore materials; 17 - skip lift;

23 - bunker trivia agglomerate.

Mixing of agglomerate and pellets occurs on the conveyor by coordinating the time of their unloading from weight-metering devices.

In accordance with the existing charge feeding system, agglomerate mixing with pellets is achieved if, at the moment of opening the shutter of the pellet bin weigher, a portion of the agglomerate is under heat of the respective pellet weights.

The initial matrix of a given sequence of operation of the units of the loading system and the masses of iron ore materials can be presented in the form of the following table.

Skip portion number The number of the sinter bin from which the unloading is performed The specified mass of a portion of agglomerate, t Hopper number from which additives or pellets are unloaded Target weight of additives or pellets Hopper number from which pellets are unloaded Preset Pellet Mass one. A ₁ M _health ^A D ₁ M _health ^D About ₂ M _health ^O 2. A ₂ M _health ^A About ₁ M _health ^O - - 3. A ₃ M _health ^A About ₂ M _health ^O - ^- . . m. A _m M _health ^A D _n M _health ^D O _k M _health ^O Go to 1

m, n, k are natural numbers.

Using the data on the distance from the sinter screen A _i to estrus corresponding to the line for unloading pellets or the addition of hopper O _i , the path is calculated that passes the agglomerate to estrus of bunker weights for pellets (О ₁ , О ₂ ) Λ _S.

ΔS = S _BA -S _BO

The time interval between the beginning of the unloading of the agglomerate on the conveyor and the moment of opening the estrus of the hopper weights of the pellets is determined by the equation

Algorithm for determining the operating time of the screen when unloading the sinter onto the conveyor ( _screen r)

The agglomerate discharge time to the conveyor is determined at a known rate of agglomerate discharge from the screen to the conveyor ν _pouring :

For each screen, the pouring speed is a value that depends on the fractional composition of the material in the hopper and the performance of the screen. Therefore, at each unloading is according to the equation

Here M ⁱ _agglomerate is the mass of discharged agglomerate for the current load;

- the working time of the screen at the i-th unloading.

M ^igr _i is found as the difference between the mass of LME loaded into the hopper scales of the material and the mass of pellets and additives

Here - the mass of fats in the hopper scales of the material (position 16, Fig. 1).

- mass of pellets in the bunker scales of pellets (position 8, Fig. 1).

- the mass of additives in the hopper scales of the material (position 9, Fig. 1).

The information obtained is used to adjust a given mass of material for the next unloading.

Are located , and by equations

As a result of the calculations, it is possible to form a matrix of information necessary for the operation of the equipment of the charge feeding system, which is presented in table 2.

Serving Number The number is Working hours Bun number Assigned Time interval Feeder number Assigned Time interval

in load cycle hota you roar agglomerate core pellet weights feed weight of pellets between the start of the screen and the opening of the shutter of the bunker scale of the pellets additives feed weight between the start of the screen and the operation of the additive feeder one A _i τ _screen O _i τ _SOO D _i τ _{S additionally} 2 A _i τ _screen O _i τ _SOO D _i τ _{S additionally} A _i τ _screen O _i τ _SOO D _i τ _{S additionally} m A _i τ _screen O _i τ _SOO D _i τ _{S additionally} The algorithm can be represented as follows Operation number Moment of time (team) Operation in progress one The loading of the portion into the bunker scales of the ЖРМ is completed (Fig. 1, position 16) Payment , , , τ _screen 2 Pellets can be loaded into hopper scales Set of a predetermined dose of pellets in a bunker scale 3 Unloading of a portion from Skip material unloading

bunker scales four Skip lift allowed Skip lift 5 τ ₀
Allowed to load portions into skip Turning on the sinter hopper screen 6 τ _{S additionally} Inclusion of an additive feeder 7 τ _SOO Opening the shutter of the pellet bin weighing scale 8 T ₀ + τ _screen Screen off 10 The mass of materials in the bunker scales of the ЖРМ is constant Measuring the mass of material in a hopper scale eleven Return on 1

EXAMPLE

Blast furnace smelting was carried out using titanium-containing agglomerate, pellets, coke and additives in the charge. The chemical composition of cast iron and slag was measured, and the time of joint production of cast iron with slag. The results of the heat in different periods are given in the table.

Period 1 - (basic) work on the VTI 102-D-130-2004.

Period 2 - (experimental) work with mixing agglomerate and pellets.

Period 3 - (comparative) work on VTI 102-D-130-2004.

Standard deviations of the components of the smelting products

Period Indicator Base Experienced Comparative Specific iron consumption, kg / t 970 971 969 Theoretical yield of cast iron, t / day 5611 5590 5467 Coke consumption, kg / t 397 401 404 Fuel consumption, kg / t 1631 1628 1629 σ _slag 0,0332 0.0265 0,0274 σ _[V] 0,0357 0,0289 0,0446 σ _[S] 0.0059 0.0051 0.0061

Analysis of the data shows that the proposed utility model allows us to solve the problem.

References

1. A.S. USSR No. 1544807, class C21B 7/20, publ. 02/23/1990, BI No. 7.

2. German patent No. 2825718 A1, publ. 06/12/1978

3. RF patent No. 2023012, cl. C21B 7/20, publ. November 15, 1994

4. Temporary technological instruction "Cast Iron Production", VTI 102-D-130-2004, OJSC "Nizhny Tagil Metallurgical Plant", N-Tagil, 2004

Claims (1)

A complex for smelting cast iron from titanium-containing agglomerate and pellets of different basicities, including a blast furnace, systems for dispensing and loading iron ore materials, coke and additives, supplying combined blast, venting blast furnace gas and cleaning melting products, characterized in that it additionally contains a system for mixing agglomerate and pellets before loading them on the top.