SU445683A1 - The method of calcination electrode coke - Google Patents

Description

one

The invention relates to the technology of manufacturing carbon-graphite materials, in particular, to the method of nocasting electrode coke to obtain self-baking anodes used in the manufacture of aluminum by the electrolyzing of cryolite-alumina melts.

A method for calcining electrode coke in rotary kilns is known, including the preliminary separation of coke into fractions and their subsequent mixing. The whole mass of crushed coke is classified into fractions of more than 4 mm and less than 4 mm. The coarse fraction is then calcined in a furnace, and the coarse fraction is sent directly to the fridge on a layer of calcined coke to calcine the fines at the expense of teila obtained from the coarse fraction.

The disadvantage of this method is that the heat obtained from the coarse fraction is not enough to calcine the fines in the refrigerator.

Field tests show that volatile substances are poorly removed from the feedstock, especially petroleum coke. This results in SURFACE electrical resistance and a decrease in the mechanical strength of the coke. The use of such coke for the preparation of anode masses is not economically viable: the anodes of aluminum electrolysis cells have an increased electrical resistance, which leads to the loss of electrical energy to aluminum.

The aim of the invention is to optimize

conditions of irokalyvani different fractions.

The goal is achieved by the fact that a fraction smaller than 25 mm is introduced into the zone of the heated flow fractions larger than 25 mm with

temperature of 1100-1300 ° C.

According to the proposed method, after preliminary crushing, coke is classified and screened, the coke is divided into two fractions: more than 25 mm and less.

25 m.m. After that, the coarse fraction is sent to a rotary oven with a cold cut, and a small fraction is sent to a furnace zone with a temperature of 1100–1300 ° C, i.e., 3–15 m from the kiln nozzle. And small

the fraction is fed under a coarse layer, which reaches this zone at the irokalke.

Alternatively, a small fraction of coke from the side of the hot edge of the furnace is iodized through the pipe of the vibrating conveyor or heat sink.

The proposed method allows to increase the productivity of the rotating tube furnace by increasing the fraction of the crucible fraction and reducing the residence time of the fines in the calcination zone; i get a coke

with high electro and mechanical swaps; reduce the loss of coke with flue gases by reducing the residence time of the fine fraction in the furnace zone (the residence time is one fifth of the usual time); more fully utilize the heat released during the combustion of the fuel by the furnace nozzle; achieve lower coke oxidability by separating volatiles from the fines and forming a reducing atmosphere for coarse ones. Combustion of volatiles reduces fuel oil consumption for heating the coke calcination furnace.

Subject invention

The method of calcining electrode coke in rotary kilns, including preliminary separation of coke into fractions followed by PM mixed, characterized in that, in order to optimize the conditions for calcining different fractions, a fraction smaller than 25 mm is introduced into the zone of the heated flow of a fraction larger than 25 mm with temperature 1100-1300 ° C