“LENNIIGIPROKhIM” LLC, Saint Petersburg, Russia:

A. A. Pedro, Professor, Head of Laboratory of High-Temperature Processes and Apparatuses, phone: +7 (812) 592-64-45

National Mineral Resources University, Saint Petersburg, Russia:

A. P. Suslov, Pro-rector

The nature of changing and existing of constant component (U_cc) in the phase voltage of ore smelting furnace with closed throat is considered by the example of phosphorous and carbide furnaces. The constant compound, explained by the contact of electrode with melt, is caused by the following factors:

— chemical interactions of this melt with carbonaceous electrode;
— decreasing of voltage drop on the furnace bath by the Gibbs thermodynamic potential value in the half-cycle, when electrode is anode;
— increasing of the voltage drop by the Gibbs thermodynamic potential value, when electrode is kathode.
The value of this U_cc depends on the melt composition, temperature on the electrode surface, contacting with this melt, and part of electrode current, passing through this contact. Direction of Ucc in measuring circuit lays from the melt (or coke, floating on the surface of this melt) to the electrode. That's why, there can be substantiated, that the melt is positively charged. The constant compound, defined by the valve action of electric arc of alternating current, depends on the following factors:
— material of electrodes, between which the arcing is observed (i. e. the operation of liberation of electrons from the cathode spots in the half-cycles, when they are situated on electrodes);
— temperature of cathode spots and gaseous medium with arcing.
U_cc depends on the component of melt, because one of electrodes is the melt or coke, treated by this melt and floating on its surface. Besides, Ucc depends on the part of electrode current, passing through the arc, i. e. it depends on the arc current. Direction of U_cc, defined by arc, depends on the size of electrone emission from electrodes. The electrode (melt or, directly, electrode), which emission is higher, is anode in the measuring circuit. Size and direction of total U_cc, explained by the simultaneous valve effects of electrode with melt and electric arc of alternating current, depend on the correlation of processes of chemical interconnection of electrode with components of reaction zone. This size and direction also depend on the degree of development and arcing conditions.

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