RU2261283C2 - Method of production of briquettes from dispersed materials - Google Patents

Abstract

FIELD: metallurgy of non-ferrous metals.

SUBSTANCE: proposed method includes mixing the metal-containing dispersed materials with peat mass followed by molding. Before mixing, the peat mass is dried or moistened to moisture content of 5-20% and is ground to size 2-5 mm; then, it is treated with aqueous of sulfuring anhydride at mass ratio of sulfuric anhydride to peat of 30-60% for 5-30 min at continuous mixing.

EFFECT: reduction of losses of metal by 5-10%; increased strength of briquettes.

5 cl, 1 tbl, 1 ex

Description

The proposed technical solution relates to the field of metallurgy, mainly non-ferrous metals, in particular to the preparation for further metallurgical processing of finely ground mineral raw materials, or pulverized production waste with the receipt of additional suitable raw materials.

A known method of preparing briquettes of dusty and fine-grained waste for further metallurgical processing by mixing them with binders, for example water glass and amorphous silicon dioxide, subsequent pressure treatment and heat treatment of the mixture to give hardness to the obtained briquettes (see, for example, A.S. No. 939574, USSR, class C 22 B 1/24 for 1981).

A disadvantage of the known methods is that binders adversely affect the smelting process, the metal is not completely removed from the briquettes, a significant part of it passes into oxides and is lost along with slags, and the lining of the melting units wears out faster.

A method for producing briquettes is also known, including mixing dispersed material, for example dust with peat, and subsequent processing by pressure or drying in vacuum furnaces (Alexandrov B.M., Grevtsev N.V. et al. Technology for the production of composite briquettes based on peat. University publication, mining journal, No. 11-12 for 1997, pp. 255-258, as well as AS No. 757601, USSR, class C 22 B 1/243 for 1978). In a known method, the mixture was briquetted by extrusion and subsequent drying. As a result of industrial tests, dust removal from a shaft furnace was reduced to 0.5% with an increase in matte copper to 92.1%.

The disadvantage of this method of preparing briquettes is the low strength of the briquettes, the complexity of the process of their heat treatment, the high labor costs for additional operations, which ultimately reduces the productivity of the briquetting process.

The technical problem solved by the invention is to increase the productivity of the briquetting process and increase the strength of the briquettes.

The solution of this technical problem is achieved by the fact that in the proposed method for briquetting dispersed metal-containing materials, including mixing the dispersed materials with a peat mass, the peat mass is dried or moistened before mixing with dispersed materials to a moisture content of 5-20%, then crushed to a particle size of 2-5 mm, then treated with an aqueous solution of sulfuric anhydride at a mass flow rate of sulfuric anhydride to peat 30-60% for 5-30 minutes with constant stirring.

The essence of the proposed method is as follows.

The crushed peat mass is treated with an aqueous solution of sulfuric anhydride, which allows to obtain a cementing material, which gives the obtained briquettes strength and does not deteriorate during transportation. Only under the influence of high temperature inside the shaft furnace, directly in the process of melting, the slow combustion of peat and melting of metal occurs. Industrial tests confirmed the proposed method and almost completely eliminated metal losses during mine smelting of pulverized materials.

Example. Industrial tests of briquette production using flotation copper concentrate with a moisture content of 6.4% and peat mass with a moisture content of 15%. The preparation of briquettes was carried out in the following sequence. Peat mass was crushed to the required size, dried or moistened to 5-20%. To the resulting peat mass was added an aqueous solution of sulfuric anhydride to the desired mass ratio of SO ₃ / peat and mixed until a homogeneous state was obtained. After obtaining a homogeneous mass, copper concentrate was added to it and mixed until a homogeneous state was obtained. The resulting mixture was pressed on a roller press at a specific pressure of up to 58.8 MPa (600 kg / cm ² ). The briquettes obtained by this method were subjected to industrial strength tests by known methods. The test results are shown in the table.

Test results of briquettes of copper concentrate with peat.

Experience Number Peat mass properties Treatment with an aqueous solution of sulfuric anhydride The strength of the briquette, kg / cm ² Humidity% Fineness, mm SO _{3 / peat} ,% Min. 1 2 -3 fifty 10 18.0 2 5 -3 fifty 10 27.5 3 fifteen -3 fifty 10 30,4 4 twenty -3 fifty 10 29.7 5 25 -3 fifty 10 22.1 6 fifteen -1 fifty 10 24.6 7 fifteen -2 fifty 10 29.4 8 fifteen -3 fifty 10 30,4 nine fifteen -5 fifty 10 32.8 10 fifteen -8 fifty 10 33.1 eleven fifteen -3 fifteen 10 16.3 12 fifteen -3 25 10 25.5 thirteen fifteen -3 fifty 10 30,4 14 fifteen -3 60 10 31.8 fifteen fifteen -3 70 10 28.5 16 fifteen -3 fifty 2 14.3 17 fifteen -3 fifty 5 21.7 eighteen fifteen -3 fifty fifteen 30,4 19 fifteen -3 fifty thirty 31.5 twenty fifteen -3 fifty 40 31.5

During industrial tests, it was found that the production of briquettes is possible on high-performance roll presses and does not require heat treatment of briquettes before melting.

The technical and economic effect of the invention is to reduce the irretrievable losses of metal-containing dust and dispersed materials during its processing in shaft furnaces with blasting and partial replacement of coke with peat, which is also a connecting element in the production of briquettes.

Using the present invention will reduce metal loss by 5-10%, reduce fuel consumption by 10% and increase the resistance of the refractory lining of furnaces by 10-30% compared with known methods for a similar purpose.

Claims (5)

1. A method of producing briquettes from metal-containing dispersed materials, comprising mixing the metal-containing dispersed materials with a peat mass followed by pressing, characterized in that the peat mass is further treated with an aqueous solution of sulfuric anhydride before mixing with the metal-containing dispersed materials. 2. The method according to claim 1, characterized in that the treatment of peat mass with an aqueous solution of sulfuric anhydride is carried out at a mass flow rate of sulfuric anhydride to peat 30-60%. 3. The method according to claim 1, characterized in that the treatment of peat mass with an aqueous solution of sulfuric anhydride is carried out for 5-30 minutes with constant stirring. 4. The method according to claim 1, characterized in that the peat mass is dried or moistened to a moisture content of 5-20% before being treated with an aqueous solution of sulfuric anhydride. 5. The method according to claim 1, characterized in that the peat mass is ground to a particle size of 2-5 mm before being treated with an aqueous solution of sulfuric anhydride.