The tunnel kiln is divided into three main zones according to its process flow: the preheating zone, the firing zone, and the cooling zone, each undertaking a different thermal task.
Preheating Zone
Located at the front of the kiln, this area allows the products to heat up slowly. Flue gas flows counter-currently from the firing zone to heat the products, achieving initial heat recovery.
Firing Zone
This is the core of the entire kiln. Fuel and combustion air mix and burn here, directly firing the products at high temperatures to achieve the desired physicochemical properties.
Cooling Zone
Located at the rear of the kiln, this area cools the products with cold air. Simultaneously, the heat released during cooling is recovered; part of it is fed back into the firing zone as combustion air, and the rest is used for drying the green bodies.
