RU2356954C2 - Briquette - Google Patents

Abstract

FIELD: metallurgy. ^ SUBSTANCE: briquette includes iron-containing and zinc-containing materials, and also coupling agent. In the capacity of iron-containing and zinc-containing material it is used dust of electric furnace steelmaking, and in the capacity of coupling agent it is glass. Components ratio in briquette is following, wt %: dust of gas cleaning of electric furnace steelmaking 75-97, water glass 3-25. ^ EFFECT: receiving of ability to utilise waste products .

Description

The invention relates to ferrous metallurgy, and specifically to the composition of a briquette for smelting cast iron to produce an intermediate for the zinc industry.

Known as a prototype [1] is a briquette for steelmaking, containing iron-containing metallurgical waste, including blast furnace dust, pulverized dolomite and cement as a binder, which additionally contains gas cleaning dust from electric steelmaking in the following ratio, wt.%:

gas treatment dust 40-80 blast furnace dust 1-40 dusty dolomite 5-30 cement 1-5

Significant disadvantages of this briquette are:

- low content of zinc components in the briquette to obtain an intermediate for the zinc industry;

- high cost of briquettes obtained in connection with the additional costs of additional grinding of dolomite;

- low mechanical strength of the briquette due to the lack of reaction of the interaction of cement with dust from gas treatment of electric furnace production due to the finer fraction of the latter.

A mixture is also known [2] for the production of carbon-containing iron ore briquettes, including sludge from metallurgical industries and blast furnace dust, which contains components in the following ratio, wt.%:

sludge of metallurgical industries 70-95 blast furnace dust 5-30

Significant disadvantages of this mixture are:

- low content of zinc components in the briquette to obtain an intermediate for the zinc industry;

- low mechanical strength of the briquette due to the lack of ligaments.

There is also a method of disposing sludge blast furnace gas by clumping sludge in a bowl granulator using a 20% solution of water glass and further firing the granular sludge in a fluidized bed furnace [3].

Significant disadvantages of this method are:

- increased costs for granulation of this type of material due to the complexity of manufacturing the product in this way;

- the difficult process of remelting this material in the required quantity and obtaining an intermediate for the zinc industry.

There is also known a method of processing and obtaining raw materials for the production of zinc [4], the main source for which are sulfide polymetallic copper-lead-zinc, lead-zinc and copper-zinc ores.

Significant disadvantages of this method are:

- high costs for the production of raw materials due to mining, complex processing and processing of ore components;

- additional generation of industrial waste during the processing and preparation of ore components to obtain raw materials for zinc production.

The desired technical results of the invention are:

- obtaining an intermediate for the zinc industry in the form of trapped dust with a high zinc content;

- reducing the cost of pig iron by reducing the cost of charge materials;

- efficient disposal of industrial waste.

For this purpose, a briquette is proposed, including iron and zinc-containing materials, as well as a binder, characterized in that the dust is used as iron-containing and zinc-containing material by electric steel production, and liquid glass is used as a binder in the following ratio of components, wt.%:

Dust for gas treatment in electric steelmaking 75-97 Liquid glass 3-25

The claimed limits are selected experimentally.

The gas cleaning dust from electric steelmaking production is introduced into the briquette as iron and zinc components, and when using less than 75%, the unit’s useful efficiency decreases when using the briquette, and with an increase of more than 97% it is impossible to obtain a briquette with the required mechanical strength, providing the required gas-dynamic properties of the furnace shaft.

Liquid glass is used as a binder, and when using less than 3%, it is not possible to obtain a briquette with the required mechanical strength, and with an increase of more than 25%, the non-production costs associated with the production of briquettes increase, and the total content of the iron-zinc component in the briquette also decreases.

The inventive briquettes were made of materials with the following chemical composition.

Gas treatment dust from electric steelmaking: 8.06-10.1% CaO; 62.4-70.41% Fe ₂ O ₃ ; 4.98-6.5% SiO ₂ ; 3.57-5.6 MnO%; 1.86-6.0% MgO; 0.81-8.3% Al ₂ O ₃ ; 0.01-0.05% V; 1.90-6.50% Zn; 0.10-0.50% Cr; 0.1-0.3% Cu; 0.5-2.0% K ₂ O; 0.5-2.0% Na ₂ O; 0.30-1.20% SO ₃ ; 0.5-4.0% C; moisture - 0.10-2.0.

Liquid glass: density at 15-25 ° C - 1.30-1.55 g / cm ³ ; silicate module (SiO ₂ :

Na ₂ O · 1,0323) - 2.6-3.0.

The above components were mixed, moistened and dried under natural conditions.

Briquettes were used in the smelting of pig iron in a cupola to obtain a semi-product for the zinc industry in the form of dust trapped in exhaust gases in bag filters of gas treatment plants.

The chemical composition of the captured dust: 5.0-25% Fe _total ; 5.0-15.5% C; 3.0-10.0% CaO; 0.5-3.0% MgO; 2.0-8.0% Al ₂ O ₃ ; 6.2-8.2% SiO ₂ ; 35-56% Zn.

The inventive briquette made it possible to efficiently utilize production wastes to produce an intermediate for the zinc industry in the form of trapped dust with zinc content of at least 35% and cast iron with the required chemical composition, and the production cost of cast iron obtained is 2.3% lower than cast iron obtained from traditional materials .

Information sources

1. RU No. 2005124222/02, class C22B 1/243.

2. AS of the USSR No. 1546506, class С22В 1/24.

3. Tolochko A.I., Slavin V.I., Suprun Yu.M., Khayrutdinov P.M. Disposal of dust and sludge in the steel industry. - Chelyabinsk: Metallurgy, 1990, - 152 p.

4. Tarasov A.V., Utkin N.I. General metallurgy. - M.: Metallurgy, 1997, - 592 p.

Claims (1)

The briquette, including iron and zinc-containing materials, as well as a binder, characterized in that the iron-containing and zinc-containing material is used for gas cleaning dust from electric steelmaking, and liquid glass is used as a binder in the following ratio of components, wt.%:
gas treatment dust 75-97 liquid glass 3-25