Lime vertical preheater overview:
Vertical preheater is one of the three main hosts of active lime equipment. It has the characteristics of reasonable structure, high thermal efficiency and high level of automation, but it cannot make full use of scraps (requires feeding granules 18-50mm) and is not suitable for poor thermal stability. raw material. The vertical preheater is used in conjunction with the rotary kiln to preheat raw materials with poor thermal stability, such as activated lime or dolomite. The main function of the vertical preheater is to feed raw materials from the charging chamber into the fume material isolating cover, and uniformly distribute the conical surface of the central distribution cone in the annular stacking space between the two cylinders of the preheater body. The high-temperature exhaust gas (850-1000 ℃) discharged afterwards, uniformly preheats the material in the preheater to more than 700 ℃, during the preheating process, 30 ﹪ CaCO3 is decomposed in the preheater, and the preheated to 700 ℃ The materials are pushed into the kiln in turn by means of each pusher unloader to achieve the purpose of uniform feeding. After the heat exchange, the flue gas whose temperature drops to about 300 ° C is discharged into the atmosphere through a dust extractor. Such a calcination process not only greatly shortens the calcination time of the limestone in the kiln, but also can obtain lime with higher activity.
预热器系统主要由六大部分组成： The vertical preheater system is mainly composed of six parts:
1. Feeding chamber system: The feeding chamber is located in the upper part of the vertical preheater. It is two side-by-side feeding chambers. The upper and lower ends of each chamber are equipped with automatic control gates and vibration feeders. When a feeding chamber is feeding, The lower gate is closed, while the upper gate of the other feeding chamber is closed, and the material is discharged to the preheater body. The feeding room uses a total of 4 vibrating feeders to work alternately from the diagonal direction, and its feeding and discharging are completed by the vibrating feeder operated by the program control system. In order to ensure that cold air from outside does not enter the preheater. A material level controller is set in the feeding room to control the material level to realize continuous or uninterrupted feeding.
2. Preheater body: The heater body is located directly below the feeding chamber. The lower part made of steel plate is a cylinder, and the upper part is a cone-shaped body. The frustum is equipped with two symmetrical exhaust gas discharge pipes, and the lower cylinder is lined with a refractory material (this item does not belong to the scope of equipment design and manufacture). The material from the feeding chamber is added by a vibrating feeder to a flue gas material isolation cover which is cylindrical and has a frustum shape in the middle and is welded by a steel plate, and slides down around the central distribution cone of the steel plate. , Falling into a circular material storage space composed of a cylindrical masonry made of refractory material and the inside of the body. The gas collection chamber is located directly below the central material distribution cone. It is a space surrounded by the vault made of refractory material and the above-mentioned cylindrical masonry. The upper part of the gas collection chamber is evenly distributed along the periphery of the cylindrical masonry. There are several air inlet holes, and the discharge holes are correspondingly distributed under the air inlet holes. Just above the air intake hole in the annular stacking space, several arch blocks made of refractory material are evenly distributed along the circumference. It guides the hot flue gas passing through the air intake hole, so that the hot flue gas first flows in a circular direction to In the gap between adjacent arch blocks, it flows upward through the material layer for heat exchange and is discharged. Just above the adjacent discharge holes in the annular stacking space, a number of wedge-shaped arches made of clay bricks are evenly distributed along the circumference. Its role is to prevent the accumulation of materials in them and allow all materials to pass through the adjacent discharge holes. It is pushed into the kiln by the pusher unloader. The preheater is provided with an inspection door and a sight hole on the outer wall of the preheater, which can enter the preheater for inspection and cleaning of the air intake hole, and can also observe the internal situation from the outside. The body is provided with a ray material level controller. In addition, the refractory brick lining structure has a novel design and good sealing performance, which can ensure that the material is evenly preheated in the preheater and reaches the preheating temperature.
3. Pusher unloader device: The pusher unloader is located in the lower part of the preheater and feeds into the rotary kiln. It has several units and is evenly distributed around the simplified Chinese. Each pusher unloader is composed of an oil cylinder, a pusher, a guide box and a corresponding link. The hydraulic station supplies oil to the oil cylinders one by one. The oil cylinders move the push heads back and forth through push rods. Each push rod operates in turn to push the materials evenly into the kiln to ensure that the material layer in the preheater drops evenly. The pusher head and the guide box are made of heat-resistant chrome-nickel steel, and there is a moderate gap between each other, so it is not easy to jam. Each hydraulic push rod can realize sequential push according to the automatic control program. The wedge-shaped arch installed between the two unloaders in the simplified Chinese allows the material to fall completely into the pushing range of the unloader, so no dead angle is formed.
4. Hydraulic system: mainly includes oil tank, oil pump, motor, solenoid valve, hydraulic oil pipe, etc. Its main function is to control the pushing device to complete the pushing action.
5. Bypass pipe and auxiliary chimney: The by-pass pipe is welded from steel plate, lined with clay refractory material and provided with a flap, and a flange is used to communicate with the charging chamber of the rotary kiln. Coarse particles in the flue gas can be discharged by sedimentation. The auxiliary chimney is provided with a smoke cap, and the bypass pipe and the auxiliary chimney are only used during the initial stage of operation and when the exhaust machine or the electrostatic precipitator is overhauled or fails. The flaps leading to the bypass pipe and the chimney cap of the auxiliary chimney must be closed during normal production
6. Frame: It mainly includes columns, ring beams, etc., whose main function is to carry the superstructure of the preheater.
Address: Ziwei Shangshe, National Hi-tech Development Zone, Xi'an, China. Address: Beside 210 National Road, Kaikou Shizi, Xiqiao, Xiqiao
Phone / Fax: 029-83503037
Company QQ: 2262147708