SU395461A1 - METHOD OF THERMAL STRENGTHENING OF WELLS FROM LOW-GRASSED COPPER-NON-CELTIC CONCENTRATES - Google Patents

Description

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The invention relates to non-ferrous metallurgy, in particular, to a method for strengthening pellets from mass-nickel concentrates.

Known is the method of thermal hardening of akatysh from low-grade medpo-nickel concentrates, including the drying of pellets by suction of hot circulating gases, and the frequent obdgging of the flue gases.

The proposed method is characterized in that the calcination is carried out with flue gases with a temperature of 600-650 ° C in the presence of liquid fuel in the bed of the calcined material, which makes it possible to increase the yield of strong pellets.

The hardening of the dried pellets is as follows.

1.5% (based on the weight of the mixture) of refined fuel oil with a temperature of 90 ° C is introduced into the charge for pelleting. Okatanpe is performed on a dish-shaped grappulator with a diameter of 1 m. The yield of fractions - 15 + 5 mm is not less than 95 ° - - Dried pellets are placed in a 300 mm diameter bowl, and then 0.5% of the upper layer is fed sphty) sprayed. Mazuha, .. with the temperature of 90 ° C. - -:.

Calcining the pellets is carried out with --- through. a layer of thin gases with temureture, DOO--

650 ° C. Due to the burning in the fuel oil layer, the temperature along the entire height of the layer reaches 1125 - 1150 ° C. Burnt pellets during subsequent cooling with a water-air mixture do not break down, they show an extremely low drum sample (the output of a class less than 5 mm does not exceed 3-5%). The crush strength of the pellets is 200-300 lgg / pellet versus 40-70 kg when fired in a known manner.

Low-temperature obdg allows 40-50% specific fuel consumption. Desulfurpansn during obdgge a composition of 28 to 30% of the volume of 40-50% with the known firing method.

A positive effect is obtained when the pellets loaded into the grate bowl 13 have two layers, the upper layer (1/3 of the height) contains an increased amount of fuel oil (3%), nzpny layer (2/3 layers) - 1.5% of fuel oil.

The method used improves the quality of pellets and reduces production costs.

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Subject p z about b ete e p and

Thermal hardening of akatysh

,., from low-grade copper-nickel concentrates, including drying of nrosasy pellets30. Aaiell hot circulating gases, partial calcination by suction of flue gases containing free oxygen, characterized in that, in order to increase the yield of strong pellets, calcination is conducted by flue gases with a temperature of 600-650 ° C in the presence of liquid fuel in the layer of calcined material.