The pressure in the kiln is mainly realized by the air duct of the fan. In general tunnel kiln, the pressure in the kiln is controlled by air cooler, smoke exhaust device and fan under the vehicle. The choice of zero pressure point is very important. Theoretically, the zero pressure point should be in the last parking space in the preheating zone. The opening of the exhaust fan has a great influence on the zero pressure point, which is mainly used to adjust the tropical temperature. The amount of cold air is mainly controlled by considering the preheating fan and the amount of smoke exhaust. In principle, as long as the bricks out of the kiln are not hot.
The atmosphere system should be determined by referring to the properties of the bricks you burn. Different bricks correspond to different atmospheres. Generally, high-alumina products need oxidizing atmosphere, and products such as magnesia-carbon bricks should choose reducing atmosphere. The ratio of air volume to fuel is technically a problem of air excess coefficient. Generally, the ratio of air volume to gas volume can be judged by the color of flame.
Generally, the pressure system is stable, the fan opening is appropriate, and the stable air supply temperature system will not fluctuate too much.
Considering your problem, I suggest you turn up the exhaust fan appropriately and try to increase the primary air volume. Your kiln has a large amount of flue gas, which is probably related to the coal quality used. Are you sure about anthracite?
In a word, each tunnel kiln has its own characteristics, which should be judged according to your actual situation.
I wish you an early solution to the problem!
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