Preheater is a hot exchange equipment of the dry rotary kiln system. Suspension preheater is used to hot exchangr and separate between dry raw powder and the hot air in the rotary kiln. The suspension preheater has good preheated effect, materials have good adaptability, System pressure consume low power, and high resolution ratio in kiln, anti-blocking and good tightness.we separate the preheated raw materials and some materials preheated by preheater, which replaced some functions of kiln, and get the result of shorting kiln length. At the same time, internal kiln makes hot exchange in accumulation state, which is moved into preheater in suspension state. This can make raw materials blend with hot air discharged from kiln, and increases the materials touch surface, and it has high speed of hot transfer, high ratio of hot exchange , and achieving the aim of improving system production efficiency and lowing hot consumption.
The working principle of preheater
1. The hot exchange function of preheater
The main function of preheater is making full use of waste gas and heat discharged from kiln and decomposing furnace to heat raw materials, and preheat the raw materials and decompose part of carbonate. In order to improve the the hot exchange ratio between gas and solid and further achieving the result that calcination system’s good quality, high production, low consumption. It mut have three functions of uniform separation of gas and solid, high exchange speedand high separation efficiency.
2. Material dispersion
The raw materials feeded into the pipe of preheater, because of the impact caused by the air high speed up, raw materials turn up and move along with the air, at the same time, it is separated. The distance that materials down to the turning point and the degree that materials are separated determined by the air speed, materials nature, gas-solid ratio and equipment structure and so on. Therefore, in order to make the materials equably separate and suspend with high speed in rising pipeline, following matters must be remembered.
(1) Choosing proper feeding position;
(2) Choosing proper pipe wind speed;
(3).Properly controlling the particle size of raw materials;
(4) Ensuring that feed materials are uniform;
(5) Adding device for spillage in the feed mouth