Main components and working principle of scraper centrifuge

The scraper centrifuge mainly consists of a drum, a distribution head, a slurry tank, a mixer, a scraper discharge device, a connecting pipe, a transmission system, etc. The main components are briefly described below.

(1) The drum is the main component of the scraper centrifuge. The surface of the drum is covered with a filtering surface formed by supporting multiple L-plates and filter cloth. The surface of the drum is divided into multiple filtering chambers in the radial direction. Both sides of the drum are supported by bearings, with one side connected to the driving system and the other side connected to the distribution head. Each filter chamber is connected to the corresponding interface of the distribution head's moving disc by a connecting pipe, and the number of rotary drum vacuum chambers can vary depending on the structure and application of the rotary drum.

(2) Allocation head: The allocation head is a major component of this device, which realizes the function of orderly connecting the filter chamber with the filtering area, washing area, suction area, and unloading cake area during operation. The vacuum distribution plate is composed of moving plate, fixed plate, sealing plate, compression spring, compression bolt and nut, etc. The moving plate is connected to the scraper centrifuge drum by a connecting pipe. In order to achieve the separation of filtrate, washing and drying areas, and backflow areas, there is a separation zone (dead zone) between each area on the fixed plate. At this time, the connection port on the moving plate is not connected to any working area, which is commonly referred to as the dead zone. In order to ensure effective separation between the backflow area and the filtering area, reduce vacuum leakage, the angle of the dead zone between the backflow area and the filtering area is larger than that of other separation areas. In order to extend the working life of the moving plate and the fixed plate, there is a set of large-sized mechanical seals between the fixed plate and the moving plate.

(3) The connecting pipe is used to connect the various vacuum chambers of the rotary drum with the interfaces on the distribution plate. Its function is to connect the rotary drum with the corresponding working areas of the distribution plate when working in various working areas.

(4) The methods of scraper centrifuges include scraper, rope bundle, discharge roller, drum belt, and other forms. When using a scraper to unload filter cake, the composition of the filter cake and the distribution head, as well as the moving disc, are required

The adhesion of the filter cloth is not very strong. Under the condition of compressed air blowing back, the filter cake can detach well from the filter cloth. The filter cake can be removed from the filter cloth using a scraper. Due to the difficulty of cleaning the filter cloth of the scraper centrifuge using a scraper for unloading during operation, this model requires that the filter cake cloth is not easily blocked by materials.