A small tunnel kiln for firing corundum refractories

Conclusions The special features of the small (working volume capacity 6. 8 m³) tunnel kiln for firing corundum refractories are: firing with a gas-air mixture, absence of combustion chambers between the charges, absence of end doors, and slow kiln truck speed (13 cm/h). The corundum bricks are fired in the kiln for 136 h at 1660°C.The gaseous medium of the firing zone contains oxidizing and reducing components.The faults of the kiln are: nonuniformity of the firing of the bricks, inadequate firing temperature level, and unsatisfactory performance of the first six positions of the heating zone where heating takes the form mainly of a thermal shock in the region of the last two (in the direction of the gas flow) pairs of connections for the extraction of the combustion productsTo improve the quality and economics of the firing process, it will be necessary to improve the heat insulation of the kiln channel, to provide channels in the floor, and to modify the heating and gas extraction systems.Translated from Ogneupory, No. 7, pp. 8–15, July, 1977.