RU2176675C1 - Charge for production of fluxed nickel sinter - Google Patents

Abstract

FIELD: non-ferrous metallurgy; production of nickel sinter. SUBSTANCE: change-includes nickel ore, flux and solid fuel. Used as flux are limestone and gypsum at the following ratio of components, mas.%: solid fuel, 6.0-9.0; limestone, 10.0-16.0; gypsum, 12.0-18.0; nickel ore, the balance. EFFECT: enhanced strength of sinter; low consumption of coke in melting matte. 2 tbl, 1 ex

Description

 The invention relates to the field of non-ferrous metallurgy, in particular to the production of nickel agglomerate.

A known mixture for producing agglomerate [1], where waste flux slag or reverse converter slag of nickel production with a grain size of 30 mm, with a content of Ni = 0.11-2.0%, Co = 0.06-0.35%, is introduced as a flux the ratio of FeO / SiO ₂ = 1.8-2.4 and in an amount providing the ratio of FeO / SiO ₂ in the finished agglomerate 0.5-0.8.

 The disadvantage of the mixture for the production of fluxed agglomerate is its low strength and low content of calcium and sulfur oxide in the agglomerate, which requires additional input of limestone and a sulfidizer into the charge of the mine smelter, which increase the coke consumption during nickel matte smelting.

The closest in technical essence and the achieved result is a mixture for the production of fluxed sinter [2], which includes oxidized nickel ore, sinter recovery, limestone, ferrous metallurgy slag and coke breeze in the following ratio, wt.%: Limestone 0-25, slag ferrous metallurgy 5-20, coke breeze 16.5-17.6, oxidized nickel ore - the rest. When sintering the specified composition of the mixture, the agglomerate has a strength (B ⁺⁵ ) of 48.5-53.8%. The composition of the charge does not include sulfur-containing material, therefore, the sulfur content in the agglomerate is low.

 The objective of the invention is to increase the strength of the agglomerate and reduce the consumption of coke in the smelting of nickel matte.

This goal is achieved in that the known mixture, including the ore part, flux and solid fuel, according to the invention as a flux contains limestone and gypsum in the following ratio of components, wt.%:
Solid fuel - 6-9
Limestone - 10-16
Gypsum - 12-18
Nickel Ore - Else
The limits of solid fuel content are determined by the task of obtaining a strong agglomerate. When the solid fuel content in the sinter charge is less than 6%, the strength of the sinter is reduced. When the solid fuel content in the sinter charge is more than 9%, the strength does not increase and the coke consumption in the production of matte increases.

 Limits of limestone content are determined by the chemical composition of nickel ore. When the limestone content in the sinter charge is less than 10% during matte smelting, it is required to add raw limestone to mine smelting, which increases the coke consumption. When the limestone content in the sinter charge is more than 16%, the melting temperature and the amount of slag in the mine smelting increase, which leads to an increase in coke consumption.

 The limits of the gypsum content are determined by the task of producing agglomerate with the amount of sulfur necessary to produce matte. When the gypsum content in the sinter charge is less than 12%, it is required to additionally introduce a sulfidizer into the mine smelting, which increases the coke consumption. When the gypsum content in the sinter charge is more than 18%, the strength of the sinter decreases.

 A comparative analysis of the proposed technical solution with the prototype showed that the mixture for the production of fluxed nickel agglomerate differs from the known one in that it contains limestone and gypsum as a flux, with a previously unknown ratio of components. Thus, the inventive charge meets the criterion of "novelty."

 An analysis of the charge compositions known in the technical and patent literature did not reveal their use in order to obtain agglomerate with increased strength and to reduce coke consumption in the production of nickel matte.

 An example of a specific implementation. Agglomeration charge consisted of coke breeze (solid fuel), limestone, gypsum and nickel ore. In the experience of the prototype as a flux used reverse converter slag of Nickel production. The compositions of the components are shown in table 1. The components of the charge were dosed in predetermined proportions, mixed, moistened, pelletized, loaded into an agglomerate, ignited and sintered with air suction. Agglomerate was tested for strength in the drum. For the obtained agglomerate compositions, production indices in a shaft furnace were calculated on the basis of material and heat balances of the smelting. The test results and calculations are presented in table 2.

 Analysis of the above results shows that the use of the inventive charge for the production of fluxed nickel agglomerate helps to increase its strength from 70 to 75.0-80.7% and reduce coke consumption during smelting of nickel matte in shaft furnaces from 26 to 16.5-22.5 %

Sources of information:
1. Patent of Russia N 2092587, Applic. 03/17/95, Publ. in B.I. 1997, N 28.

 2. A.S. SU 1587068 A1, CL C 22 B 1/14, publ. 08/23/1990.

Claims (1)

The mixture for the production of fluxed Nickel agglomerate, including Nickel ore, flux and solid fuel, characterized in that the flux contains limestone and gypsum in the following ratio, wt. %:
Solid fuel - 6 - 9
Limestone - 10 - 16
Gypsum - 12 - 18
Nickel Ore - Else

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