Rotary tunnel kiln VS traditional tunnel kiln
The rotary tunnel kiln is an improvement and upgrade of the tunnel kiln. The significant feature is that the bricks do not move, while the kiln body moves in a rotating manner. The rotary kiln body is entirely made of steel structure and runs along a circular track. The rotary kiln is divided into drying section, preheating section, firing section, insulation section, and cooling section from front to back. The billet distribution system runs in the same direction as the kiln body, dividing and stacking the billets simultaneously. The rotating kiln body moves forward intermittently on the track, with the front end ‘swallowing the bricks in’ and ‘spitting the fired bricks out’ at the rear end, completing the entire process of drying, preheating, roasting, cooling, and discharging the bricks in sequence. Traditional tunnel kilns, on the other hand, rely on kiln cars loaded with to move into various fixed roasting areas and complete the roasting process.
Compared with traditional tunnel kilns, rotary tunnel kiln has many advantages in economy, environment, management, etc.
1. Low invest, shorter construction period.
The green bricks are stacked directly on the ground of rotary kiln once and all; the baking is by the movement of kiln body. Therefore, no need kiln cars and kiln car running facilities, reducing investment and daily maintain cost. The total investment cost of rotary kiln with 300,000 pcs bricks is 50% lower than that of tunnel kiln with same output. The construction period of the rotary tunnel kiln only takes 4 months.
2. Big cross section, big output
The cross section of traditional tunnel kiln is 2.7m to 4.5m, whereas rotary tunnel kiln’s cross section is around 9 m, which could bake more bricks at one time and could bake more bricks one day.
3．Saving and low energy consumption
Burning bricks requires coal or gas consumption. How to improve thermal efficiency is the key point of sintering kiln technology. The sintering of bricks is between 850 ℃ and 980 ℃. The rotary tunnel kiln uses aluminum silicate refractory fiber bricks as kiln wall insulation materials, which not only reduces the weight of the kiln body, the thermal expansion, and contraction stress of the kiln body, but also greatly improves its insulation. The kiln temperature is maintained for a long time, and more bricks are consumed in a large section at once. The heat generated by internal combustion effectively increases the temperature inside the kiln body and saves energy. In ordinary tunnel kilns, in order to protect the kiln car from the hot air from the ground above the kiln car, addition air supply is used in the underground kiln car channels. In the rotary tunnel kiln, no kiln cars, no need this underground air supply either. So, the ground temperature is directly and fully utilized.
After stopping coal feeding and air supply for 48 hours in actual production, the baking could be restarted after re-feeding coal and air supply. This is impossible in the operation of ordinary tunnel kilns. The rotary tunnel kiln reduces the firing temperature of the bricks to room temperature, and the heat emitted is sufficient to dry the same volume of wet bricks. This eliminates the need for a hot air furnace and the use of superheat roasting technology to consume more coal for drying. In the heat supply system of a rotary tunnel kiln, that is to say, all the heat emitted by firing bricks has been carried by the wind in the kiln to the roasting and drying sections for combustion support and drying. The energy-saving of the rotary tunnel kiln is a significant feature, and its reasonable process design, layout, and simple logistics route have significantly reduced the energy consumption of the entire brick factory.
4. Fully automatic, saving manual work, improving working environment, higher qualification
Ordinary tunnel kilns require more workers, with high labor intensity and harsh artificial environment. The rotary tunnel kiln adopts mechanized operation and automated digital control system in all aspects, and the temperature inside the kiln is directly displayed on the display screen of the control system. The foolproof operation is very easy, avoiding practicing period and improving the yield. The working environment is neither dirty nor hot, creating a garden style brick factory for you.
5. Suitable for a wide range of raw materials, especially suitable for producing new wall materials
Traditional tunnel kilns are not suitable for Chinese colloidal clay. Our company has improved and innovated the new rotary tunnel kiln technology, which can adapt to various raw materials such as coal gangue, shale, fly ash, river bottom sludge, construction waste, etc. It can produce multiple specifications of products such as standard bricks, hollow bricks, porous bricks, and irregular bricks.