Tunnel roasting kiln can be divided into straight tunnel kiln (with kiln car) and mobile rotary tunnel kiln (without kiln car). Straight tunnel kilns can be further divided into masonry tunnel kilns and prefabricated tunnel kilns in terms of construction methods. The mobile rotary tunnel kiln belongs to the assembled tunnel kiln.

     Straight Tunnel Kiln:

(1)   Main products: sintered bricks, common bricks, porous bricks, hollow bricks/blocks, roof tiles, hollow wall panels.

(2)   According to the different output, the inner width of the tunnel kiln is divided into the following types:

① the inner width is 3.6 and 3.7 meters, suitable for daily output of 150,000-200,000 blocks, and annual output of 50-66 million (common bricks)

② the inner width is 4.6 and 4.8 meters, suitable for daily output of 210,000-250,000 blocks, and annual output of 69-82 million (common bricks)

③ the inner width is 5.4 and 5.6 meters, suitable for daily production of 260,000-300,000 pieces, and annual output of 85-100 million (common bricks)

④ the inner width is 6.9 and 7.2 meters, suitable for daily output of 310,000-400,000 blocks, and annual output of 102-132 million (common bricks)

⑤ the inner width is 9.2 and 9.4 meters, suitable for daily output of 600,000-620,000 pieces, and annual output of 165-200 million (common bricks)

(3)   Kiln Body Structure

Assembly Type Tunnel Kiln

   The kiln wall and kiln roof are factory processed into different units and spliced on site. The structural form of kiln wall is non-sintered clay refractory concrete wall panel + high-strength heat-resistant stainless-steel component + refractory fiber module + steel structure + enclosure pressure steel plate. The structural form often used on the kiln roof: light mullite plate + high-strength heat-resistant stainless-steel components + aluminum silicate refractory fiber blanket + steel structure.

(4) Firing temperature: 950-1050℃

(5) Firing cycle: 26-40h

(6) Length of tunnel kiln: 110-170m

(7) Length and size of kiln car: It is determined according to the size of the billet stack and the internal and external combustion method. The length and size of the commonly used kiln car are: 3600mm, 3900mm, 4100mm, 4200mm, 4350mm, 4800mm, etc.

(8) Firing method: all internal combustion roasting; all external combustion roasting; combined internal and external combustion roasting.

(9) The roasting kiln is often equipped with a smoke exhaust system, a combustion system, a waste heat system, a backburning system, a cooling system, and a bottom pressure balance system. Each system consists of fans, pipes and regulating valves. The kiln has a large section, high output, small temperature difference between sections, and good thermal insulation performance. Computer automatic monitoring and control system to ensure the stability of thermal parameters and roasting quality.