SU1339136A1 - Charge for melting synthetic slag - Google Patents

Abstract

The invention relates to ferrous metallurgy, namely the production of synthetic slags for extra-refining. The purpose of the invention is to increase the sulfur absorption capacity of synthetic slag, reducing its cost. The mixture contains components in the following ratio, wt%: waste slag of aluminum production 26-68; lime 10-29; calcite 18-49. Calcite is an oxidizing agent for aluminum in the slag and at the same time a supplier of an additional amount of calcium oxide to achieve an optimum CuO / AlO ratio in the refining slag. The desulfurizing ability of the resulting slag is 10–14% Bbmie than that of the known. 4 tab. (L oo oo with SLE Oi

Description

1133

This invention relates to the steel industry, namely the production of synthetic slags for secondary furnace

refining.

The aim of the invention is to increase the sulfur absorption capacity of synthetic slag and reduce its cost.

The essence of the invention lies in the fact that in a mixture containing aluminum salt

6-20

Screening slags of machine-building plants

The use of calcite as an oxidizing agent allows to obtain the ratio of the main components of the extruded-alumina slag CaO / A1 0 1.22, which provides the required level of physicochemical properties (fluidity, basicity), which is necessary to achieve sulfur content. in metal (0.015%)

The proposed mixture for smelting synthetic slag has the following ratio of components, wt.%:

Aluminum lacquer

production 26-28

Calcite18-49

Lime10-29

The lower limit of the calcite content is limited to 18% by weight.

At lower values it does not provide the necessary slag sulfur absorption capacity.

When the calcite content is 18-49% by weight, the slag has the lowest melting point.

The amount of aluminum slag production is from 26 wt.%, When its effect on the degree of steel desulfurization begins to have an effect, to a value of 68 wt.%, Which increases the viscosity of the slag.

362

nano-containing material and lime, additionally injected calcite (e.g. limestone, chalk, limestone), which is an oxidizing agent

aluminum, and dumping aluminum slag is used as the aluminum-containing material.

The chemical composition of aluminum production slag is presented in table. 1. Table 1

40-70 2.0-2.5 1.0-5.0

30-60

2-15 1.0-5.0

The minimum lime content in the charge, at which a noticeable decrease in the melting temperature and viscosity of the slag occurs, is 10 wt. At the upper limit, the value is 29 wt.%, Since it is impossible to provide higher lime contents at this ratio of the other components.

The composition of the charge for smelting synthetic slag is given in Table 2.

table 2

2 3 4 5

25 26 31 39

42

45 49 42 42 35

30 29 27 19

23

 13J9r

FI Rodo / Gzhemnr tpbl. 2

Comparative studies of the refining properties of synthetic slag from the proposed and well-known charge are carried out under the conditions of an oxygen converter plant. The mixture of the proposed composition is prepared from slags of aluminum production of a fraction of 3 mm, crushed limestone fraction DL mm, and powdered lime.

Slag-forming mixture of known composition is prepared from aluminum slags, nitrate, lime and fluorspar. Draw materials

five

0

0

61

b t to a fraction of 1 mm and vanish. " l mix.

The mixture before. The gosganyl is under fire in the pilot field (cyclone slag melting site,

In the process of smelting the charge n of the cyclone pit accumulator in the temperature zone 800-900 C, the metallic aluminum in the slag reacts with calcite with the release of an additional amount of heat (293.3 kJ / mol) and the formation of the necessary components of the synthetic slag, CaO and AljPj. The extra heat generated increases the temperature of the slag, reduces its viscosity and energy consumption for its slagging.

Synthetic slags of the proposed and known compositions are treated with steel grade D in a steel casting ladle with a capacity of 60 tons. The consumption of slags is 40-50 kg / ton of steel. During the experiments, the temperature and viscosity of the slags are determined, as well as their desulfurizing ability is analyzed4.

The composition and physico-chemical properties of the slags are given in table. 3 and A.

Table 3

The data table. 3 indicate that the known slag-forming mixture contains an increased amount of CaO (68–78 wt.%), Since at the indicated temperatures (1250–150 ° C) CaF is additionally available from the source.

KOM of calcium oxide, which is formed by the interaction of hydrofluoric and alumina-mini oxide by the reaction

 H.CaFj) - (,) 3 (CaO) - | -2 LTK

bring to a breach of the relationship between the members of an iitaka homo-thinner

() and the CaO component that thickens it, which significantly increases the viscosity and reduces its desulfurization ability.

The data table. 4 indicate a higher refining ability of the proposed mixture for smelting synthetic stick; the degree of desulfurization of the metal is higher by 14–16% than with the use of the slag and-1G) of naphp-n composition. In this case, the slag at 0.3 - 1.0 rubles. for 1 ton cheaper than pesticide).

about rmula inventions

1339136 and

a t g n

The mixture for smelting synthetic slag, including aluminum-containing material and lime, characterized in that, in order to increase the slag's absorptive capacity and reduce its cost, it also contains calcite.

Editor N. Gunko

Compiled by V. Saramutin

Tehred M. Khodanich Proof-reader I. Erdeyi

Order 4185/18 Circulation 549Subscription

VNIIPI USSR State Committee

for inventions and discoveries 113035, Moscow, Zh-35, Raushsk nab., 4/5

Production and printing company, Uzhgorod, st. Project, 4

eight

and as an aluminum-containing material - waste slag aluminum production in the following ratio, wt.%: Waste aluminum slag

production 26-68 Lime10-29

Calcite18-49

Claims (1)

Claim The mixture for the smelting of synthetic slag, including aluminum-containing material and lime, characterized in that, in order to increase the sulfur absorption capacity of the slag and reduce its cost, it additionally contains calcite, and as aluminum-containing material - dump slag of aluminum production in the following b wearing components, dump slag wt.%: aluminum production 26-68 Lime 10-29 10 Calcite 18-49