SU844055A1 - Grinding unit - Google Patents

Description

The pneumatic pump feed line from the discharge device for the coarse-ground product of the mill, and the ratio of the number of blades in the upper and lower parts of the spreading device is 0.5-0.66.

The drawing shows the proposed grinding installation.

The grinding installation contains a centrifugal separator 1 with loading 2 and spreading 4 devices mounted on the rotor shaft 3, spreading 4 devices, mill 5 with unloading devices for coarse-ground 6 n 7 ground products.

The separator spreading device 8 is made in the form of a double-sided fan wheel, and the transport devices are made in the form of pneumatic pumps 9 and 10 of continuous operation.

In the central opening of the upper end flap 11 of the spreading device, the output end of the separator loading device connected by supply line 12 to the pneumatic pump 9 from the discharge device 7 of mill 5 is connected.

Blades 15 are installed in the upper and lower parts of the spreading device.

Grind installation works as follows.

The mill is operated as a two-stage grinding unit. The coarsely ground product of the mill is discharged through the discharge device 6, and the fine ground material is discharged through the discharge device 7.

In a known grinding plant, three separate separators are not used to classify the said products, and the grit separated after the classification of the coarse material and the fine product separated after the classification of the fine material are subjected to secondary separation.

In the proposed grinding plant from the discharge device 7, the ground product of the mill is driven by a pneumatic pump 9 through the feed line 12 through the loading device 2 of the separator 1 and is fed into the upper part of the spreading device 8 of the separator in the form of air-breathing mixture.

From the discharging device 6, the coarse-ground product of the mill by means of a pneumatic pump 10 through the feed line 14 in the form of a dust-air mixture is fed to the bottom of the spreading device 8 of the separator.

The spreading device is made in the form of a double-intake fan wheel divided into upper and lower parts by a blind partition, having upper and lower end caps with central holes to which two fluxes of material from the mill through the output ends of the supply pipes of the pneumopumps at the top of the spreading device is half the number at the bottom. The design of the spreading device and the use of pneumatic pumps as transport devices allows the two materials to be evenly distributed in the form of slightly concentrated dust curtains in the separation zone, which cannot be achieved in a known grinding plant. This provides the most economical way of distributing the divided material in the separation zone, since when the separator rotor rotates, the scattering device, made in the form of a double suction fan wheel, sucks the dust-air mixture from the feed pipes of the pumps and blades into the zone. At the same time, the power consumption for pneumatic transport is reduced.

In the proposed grinding plant, as in the well-known, the grinding products are sequentially, in two stages, separated. But, in contrast to the known sequential separation is carried out in one separator, and not in several, which reduces the metal intensity of the equipment, the cost of energy for separation, the reduction of the dimensions of the grinding plant, and hence the production costs; fine separation of coarse-ground material and grains of primary separation of fine-ground material is subjected to secondary separation, the secondary separation of the thin product is carried out after its primary separation in the area of the spreading device when entering the upper spreading device is carried out upon entry into the area of the lower spreading device. Since research has established that the separation of a coarser crushed product provides a cleaner, i.e., not needing additional separation, grains, and the separation of a finer material does not require additional separation, i.e., no additional separation is required. the use of the proposed separation scheme provides an increase in the efficiency of classification and grinding, and thus a reduction in production costs during operation of the installation.

In the upper part of the spreading device, the number of blades in which is 0.5-0.66 of the number of blades in the lower part, the ground mill product is fed.

In the upper part of the spreading device, the separation air flow is less pressured, and on the particles of the material, due to the decrease in the number of blades, less centrifugal force acts.

In the lower part of the spreading device, a coarsely ground mill product is supplied, due to the larger number of blades in the zone, greater centrifugal force acts on the particles of the material, and the separating air flow is characterized by an increased pressure.

The change in the number of blades and, caused by the flow of material to the spreading device, the change in pressure of the separating air flow in the upper and lower parts of the spreading device allows for separating different sizes of materials into one separator to separate the finished product of one given dispersion. In this case, the fine ground product is distributed closer to the zone of removal of fine particles from the separator, and coarse ground - closer to the zone of removal of large particles from the separator. As a result, finished cement of improved quality is obtained from the separator, and the grains are distinguished by a minimum content of fine particles, which ensures, when it is crushed in the fine grinding chamber of the mill, an increase in the efficiency of grinding and saving production costs.

The use of this grinding plant in the production of cement ensures a reduction in the unit cost of production, especially with increased quality of cement, by 15-20%.

Claims (2)

1. "Construction and road machines, No. 5, 1977, p. 24-25. 2.Patent of France N ° 2255106, cl. B 02C 23/12, 1975 (prototype). J / ; // //