The tunnel kiln and the kiln play the same role in the sintering products, but the tunnel kiln, as a modern sintering equipment, is essentially different from the hoffman kiln. It has become an inevitable trend to replace the rotary kiln. The main difference between tunnel kiln and hoffman kiln is that:

        Firstly ,hoffman kiln fire brick is moving in the wind does not move, the fire machine pull down kiln road ahead, all the sintering process of high temperature, preheating, cooling is completed in this process; and the tunnel kiln of brick brick kiln with real fire, workshop breaking forward, sintering process to complete this process in.

        Secondly. The top of the tunnel kiln is divided into vault and top, and all the kilns are vault. In fact, flat top is not the patent of tunnel kiln, and rotary kiln can also realize flat ceiling, but no one is willing to waste money, so it is not necessary in actual production.

        Thirdly, the tunnel kiln can realize mechanized loading and unloading truck, which can be done in the kiln, the kiln can only be done in the kiln, the kiln so difficult to achieve mechanization, the biggest drawback is round kiln, tunnel kiln kiln replaced only so, this is one of the most important reasons.

        Fourth, the tunnel kiln can realize the intelligent thermal monitoring, but the kiln has been continuously moving, and the temperature sections can not be fixed, so it is difficult to achieve thermal monitoring, and can only rely on manual observation of fire.

        Fifth, each section of tunnel kiln is relatively stable, the same section of small changes in temperature, so the inner wall and the kiln top refractory material and long service life; and the kiln due to the temperature changing constantly, so the same section of inner wall and kiln top temperature changes greatly, resulting in the damage of masonry materials quickly; tunnel kiln three years or even five years maintenance time, and the kiln annual general to repair time to overhaul once in three years.

        Sixth, because the temperature of tunnel kiln is relatively fixed, so the operation is simple, and the adobe calorific value stable, the smoke and heat valve without adjustment, and due to the temperature of the kiln in constant change, so we must adjust the sections at any time of the gate, the operation is relatively complex. Moreover, the tunnel kiln has no complicated work load, such as paper opening, block gate, brick door and so on, so the operation of tunnel kiln is more convenient.

        Seventh, the sintering process of tunnel kiln is longer than that of hoffman kiln, so the quality of product is obviously better than that of rotary kiln. The length of the tunnel kiln in 100 meters, and the kiln fire department only 10-12 kiln door, each kiln gate spacing is generally 5 meters, so the sintering process to be completed in 50-60 meters, the relative sintering time of tunnel kiln is much shorter.

        The relevant departments of the Chinese government over the years has been a ban on the kiln, the eastern regions such as Shandong, Jiangsu and other provinces in central and Henan provinces has been banned in some remote areas of the kiln, but there are a lot of kiln in production. With the continuous promotion of the national policy, it is estimated that within ten years, the kiln should withdraw from the stage of sintering brick.