SU748104A1 - Electric-resistance furnace mainly for producing silicium carbide - Google Patents

Description

(54) RESISTANCE ELECTRIC PREPARATION PREVIOUSLY FOR THE PRODUCTION OF CARBIDE The invention relates to electrodes and can be used in the abrasive industry to obtain silicon carbide. The known electric resistance furnace, mainly for obtaining silicon carbide, contains a case in which one conductive core is placed in the center, to each of whose ends a fixed current-carrying electrode is connected for connection to a furnace transformer. Its disadvantage is low productivity and high power consumption (up to 100 000 kW / h per furnace) for obtaining silicon carbide, since the volume of finished products depends on the geometrical parameters of their core parameters, and high electric power is due to lshoy area required for heating the charge to reaction temperature way Vani silicon carbide. An electric resistance furnace is also known, which contains a case with parallel conducting cores placed in it, to the ends of which, on one side, one current-carrying electrode is connected, which are connected to a kiln TRANSKREMNY: a formatter, a connecting electrode installed at the opposite wall of the housing and an insulating partition with an artificial cooling system separating both cores 172J. The disadvantage of such a furnace is the high consumption of electricity for the production, large heat losses for cooling the insulating partition, the impossibility of forcing the heating of the charge to the temperature of formation of silicon carbide. The purpose of the invention is to increase the productivity of the furnace and reduce energy consumption for SiC production. The goal is achieved by connecting the connecting electrode to one phase of the current source and both current-carrying electrodes to the other phase of the current source. FIG. 1 shows a top view of an electric furnace (the mixture is not shown); FIG. 2 is a front view of the electric furnace, a section; FIG. 3 - electrical circuit of the furnace connection to the power source. The electric resistance furnace includes a housing 1 consisting of a bottom 2, side walls 3 and end walls

4, conductive cores 5 and 6, current-carrying electrodes 7 and 8, connecting electrode 9, switch-disconnectors 10, 11 and 12, a power source, for example, a furnace transformer 13.

Cores 5 and b, for example, from graphite chips or petroleum coke, are laid along the furnace body parallel to each other. They have approximately equal resistance, and when connected in parallel, their total resistance is equal to the core resistance in known single-core resistance furnaces, for example of the type.

Current leads 7 and 8 by means of load switches

10 and 11 are connected to the same phase of the furnace transformer 13, and the connecting electrode 9 is connected to the second phase of the furnace transformer by a load switch 12.

The electric works as follows.

After loading the charge electric furnace through the load switches 10,

11 and 12 is connected to the power source 13.

A forced heating of the furnace occurs, since the charge is in the heating zone of two heating cores 5 and 6 at once. Moreover, such a forced mode of operation periodically repeats. After the cores and the surrounding SiC formation temperature reach them, which is fixed, for example, by a drop in the value of the power factor by a switch, for example, 11, the conductive core 5 is disconnected from the power source 13. A further process of formation of Si i C occurs. thermal inertia of the charge. Then, for example, after 30 minutes, the core 5 is turned on again under voltage and the forced heating of the charge is performed, after which the switch 10 and core 6 are turned off, and in this periodic heating mode the furnace runs until the end of the process of obtaining SiC.

In this electric furnace, the presence of two cores and the connection of the connecting electrode and two current-carrying electrodes to different phases of the current source allows the process of producing silicon carbide at an optimum temperature of approximately 1600 ° C using the forced charge mode (simultaneous operation of two cores) and alternating operation of each core. core. These factors lead to a sharp decrease in the decay of the already formed Sic, reduce the heat loss of the furnace and reduce the duration of the furnace under load from 29 hours to 20-22 hours,

As a result, the output of silicon carbide is increased by 40-50%, and the power consumption is reduced by 20-30%,

The invention makes it possible to increase the productivity of the furnace, to reduce the electric power consumption for the silicon carbide produced and to reduce the furnace heating time,

Claims (1)

Invention Formula An electric resistance furnace, mainly for producing silicon carbide, comprising a housing with parallel conductive cores disposed therein, current-carrying electrodes and a connecting electrode installed in opposite walls of the housing, characterized in that, in order to increase furnace productivity and reduce and consume electricity for silicon carbide production, the connecting electrode is connected to one phase of the current source, and both current-carrying electrodes to the other phase of the current source. Sources of information taken into account in the examination 1, Copyright Certificate CCS 434625, class, F 27 B 5/14, H 05 B 3/02 1973. 2, Chalykh E, F, Technologists and equipment of electrode and electric-carbon enterprises, Moscow, Metallurgists, 1972, p., .328, rice, 131 (prototype). d. v R k xs l v s-oNJ j --P-- - a M g 40 Hggg Jx  d X / 3 CtJu-S. B