Selection of the structures of tunnel kiln suspended roof thermal insulation

Conclusions A method has been developed for thermal calculation of suspended roofs taking into consideration the three-dimensional geometric configuration of the roof, the temperature relationship of the thermal conductivity of the materials, and the mutual irradiance of the projecting elements of the structure. An engineering program for calculation of suspended, and, as a particular case, of nonsuspended roofs was developed for Fortran IV algorithm language.With use of the program for thermal calculation of the roof at temperatures in the working channel from 1100 to 1900°C variations were developed of structures of the thermal insulation of tunnel kiln suspended roofs making it possible to substantially (up to 30%) reduce heat losses in comparison with those observed in existing kilns.Translated from Ogneupory, No. 6, pp. 40–44, June, 1983.     

A circular tunnel kiln for firing of refractories

Conclusions The first high-temperature circular tunnel kiln in the country, in which firing of mullite-corundum refractories with a phosphate binder at 1400–1500°C has been introduced, has been placed in service.The operation of the kiln is characterized by the high service reliability of its design elements, including the hearth system, and insignificant costs for routine repairs of the kiln equipment.Translated from Ogneupory, No. 2, pp. 40–44, February, 1985.     

Influence of the secondary air parameters on the combustion conditions of a tunnel kiln

Conclusions The operating effectiveness of the cooling zone has a significant influence on the fuel consumption in a tunnel kiln, which increases with an increase in the temperature level of firing of the refractories. Acceleration of heat exchange in the cooling zone with improvement in its thermal and gas insulation is an important step in reducing the fuel consumption in kilns.With identical effectiveness of the thermal operation of the cooling zone the parameters of the secondary air supplied for combustion do not have a significant influence on the total fuel consumption in the furnace but do determine to a significant degree the operating conditions of its burners.Translated from Ogneupory, No. 3, pp. 41–43, March, 1987.