Brief Introduction to Vertical Cooler

Vertical cooler is the main corollary equipment for limestone calcined system. It plays a role in cooling and transporting hot materials. It is the key equipment for heat recovery in limestone calcined system. The cooler has the advantages of simple structure, few moving parts and low maintenance; it strengthens the gas-solid heat exchange, so that the material is quickly cooled, which not only increases the temperature of the secondary air entering the kiln, but also improves the heat recovery rate.

Working principle of vertical cooler

The material calcined by the rotary kiln falls from the kiln head into the shell with castable lining. The over-fired or agglomerated material >100mm is stored on the upper part of the grate and discharged by the dumper. The material that can pass through the grate plate falls into the main body of the cooler. When the material is falling, the natural air blown into the lower cooler by the centrifugal blower passes through the main cooling air caps of the upper and lower air chambers and the four compartment air caps to cool the materials. The wind changes from natural wind to hot wind and enters the rotary kiln to help fuel combustion.

During the cooling process, the material stays in the cooler body for a period of time, and four electromagnetic vibration feeders are installed at the bottom of the four feeding pipes connect with the main body of the cooler. When the temperature of the material drops to about 60℃higher than normal temperature, the central control system control the operation of the electromagnetic vibrating feeder and transport it to the next process through the chain conveyor. The heat energy in the material storage process also enters the rotary kiln, saving energy, reducing pollution and achieving environmental protection.

Vertical cooler is mainly composed of kiln head cover, kiln head sealing device, grate plate device, dumping chute, cooler body, lower cooling air chamber, hood device, vibrating discharge device, discharge funnel, secondary fan, etc. (as shown in the figure below).

Structure diagram of vertical cooler

1- Kiln head cover; 2- Kiln head sealing device; 3- Grate plate device; 4- dumping chute; 5- Cooler main body;

6-lower cooling air chamber; 7-air cap device; 8-vibration discharge device; 9-discharging funnel; 10-secondary fan;

Use and maintenance

1、The structure of the vertical cooler is basically a metal structure, and its maintenance and use are carried out in accordance with conventional requirements. 

2、The main body of the vertical cooler is the heat exchange center between high-temperature materials and cooling air, and its internal temperature is relatively high. Check whether the wallboard is deformed by heat or the surface temperature of the wallboard is high. Once the local temperature is too high, the kiln should be stopped to check whether the refractory brick has fallen off, or whether there is a gap between the steel plate and the refractory brick. Measures should be taken immediately to remedy.

3、Regularly check the discharge of the kiln head through the fire hole and inspection door on the kiln head cover.

4、Regularly check the sealing condition of the scales at the kiln head. If the scales are aging and their elasticity is reduced, consider replacing them.

5、By looking at the fire hole, regularly check the accumulation of large materials on the grate plate device of the cooler and the falling bricks in the kiln. If bricks are found falling in the kiln, the kiln should be stopped for inspection and repair. The accumulation of bulk materials should not exceed 1/3 of the grate plate, and should be removed as soon as possible.

6、Regularly check the working condition of the electromagnetic vibrating feeder under the vertical cooler and the discharge condition of the material after cooling to check if it is in a normal state.

7、Regularly measure the elevation of the four columns of the vertical cooler support device. If the sinking exceeds the 3-5mm recorded during the original installation, the cause should be found immediately and measures should be taken to prevent accidents.

8、The weld edges of the main stress-bearing parts such as the foundation frame and the supporting column shall not be cracked, and repair welding shall be carried out immediately after cracking.

9、The main wall of the vertical cooler is equipped with two sets of material level measuring devices, which are used to measure the highest and lowest material levels of the materials in the cooler. When the actual material level exceeds the maximum material level or is lower than the minimum material level, the alarm signal is sent to the main control room to adjust the discharge time of the electromagnetic vibrating feeder to increase or decrease the discharge speed, thereby adjusting the material height to the normal state ensures the normal operation of the entire calcining system.