| 摘要 |
In order to facilitate oxidation of oxidisable material (typically carbonaceous) contained in refractory or clay ware during the firing of the ware in a tunnel kiln (12), commercially pure oxygen is introduced through the lances (20, 22, 24, 26, 28 and 30) into the region of the kiln where such oxidation takes place. This oxygen is directed into channels (44, 38 and 46) between stacks of ware (37 and 34, 34 and 36, and 36 and 39) for the time being adjacent the lances and carried by kiln cars (40, 32 and 42). The ware is advanced through the kiln (12) on the kiln cars in the opposite direction to the direction (48) of air flow through the kiln. The oxygen from the lances penetrates the stacks and thereby enriches in oxygen the air contained between individual items of ware in the stacks. The oxygen is typically added to the kiln at regions whose temperature is in the range 750 to 850 DEG C, and the flow of air through the kiln chosen to depress the oxygen concentration of the kiln atmosphere in carbonaceous material present at 600 DEG C to the temperature range 750 to 850 DEG C. |
