BG791Y1 - Aerated mill - Google Patents

Abstract

The aerated mill is used in the power industry. It is designed to dry and grind the coal feed to be burnt in the powder burners of the steam boilers. It comprises a housing-spiral (1) in which a rotor is housed consisting of a disc-hub (4) and front disc (6), between which radial grinding plates (5) are mounted. Door (7) closes the inlet part of the housing spiral (1). To door (7) a fixed repulsing disc (2) is mounted and at some distance in front of it a diverting deflector (3) is fitted. In this way the abrasive coal powder-containing gases are redistributed in order to produce more uniformwearing of the grinding plates (5). Deflector (3) reduces the aerodynamic resistance of the aerated mill.

Description

Technique

The utility model refers to a fan mill that is used in energy.

BACKGROUND OF THE INVENTION

Ventilation mills are very often used in the energy sector for drying and grinding coal containing a high percentage of moisture.

The windmill consists of a housing-spiral housing a rotor consisting of a disk hub and a front disc between which radially grinding plates are mounted. The grinding coals, together with the hot drying gases sucked in from the furnace, are fed through the door to the suction opening of the rotor, where they fall on the grinding plates that carry out the grinding. As a result of the coal grinding process, abrasive wear of the milling plates is obtained, which is most intense near the disk hub.

A fan mill [1] is known comprising a spiral housing in which a rotor consisting of a front disk, a hub disk and grinding plates and a door are located. The mill also includes a gas distribution unit consisting of sections - movable and stationary, disc, mounted on the door of the fan mill. It serves to distribute the gases within the suction opening of the rotor.

In the mill known from [1], part of the gases carrying abrasive coal particles are concentrated in one part of the grinding plates of the rotor, near the disk hub and cause their local wear.

The technical nature of the utility model

The purpose of the utility model is to create a fan mill with more even wear on the grinding plates.

The fan mill consists of a housing-spiral housing a rotor consisting of a front disc, a hub, with radially mounted grinding plates, a door, and a fixed disc, mounted on it.

According to the utility model, a deflector deflector is fixed in front of the fixed disc, at a distance.

According to one embodiment of the utility model, the deflector deflector is comprised of a flat disc, part of a cone and a part of a cylinder.

According to another embodiment of the utility model, the deflector deflector closes a portion of the inlet section of the rotor.

The advantage of the fan mill according to the utility model is that due to the deflection deflector, part of the drying gases containing abrasive coal dust are directed to the area of the grinding plates near the front disk of the rotor, and the amount of gases moving in is reduced. the wheel hub section and thus give a more even wear.

Another advantage of the fan mill, according to the utility model, is that the aerodynamic drag of the fan mill is reduced.

Description of the attached figures

An exemplary embodiment of the fan mill according to the utility model is presented in Figures 1 and 2, where:

Figure 1 is a sectional view along the axis of a fan mill;

FIG. 2 is a section through AA of FIG. 1.

Exemplary implementation of the utility model

The fan mill / FIG. 1 / consists of a housing-spiral 1 in which a rotor consisting of a hub 4, a front disk 6 and radially mounted grinding plates 5 is arranged. Door 7 closes the inlet portion of the housing-spiral 1.

A fixed detachable disc 2 consisting of a flat ring, a conical section in the form of a truncated cone and a sector is mounted on the door 7.

The deflection deflector 3 consists of a part of a disc, a part of a cone and a part of a cylinder. It is fixed fixedly to the fixed disc 2 so as to obtain a passage for the passage of gases mixed with coal dust.

The deflector deflector 3 occupies only part of the inlet section of the rotor, / FIG. 2 /.

Application of utility model

As can be seen from the accompanying FIG. 1, large bits of gravity-fed coal pass through the door 7 to the bottom of the grinding rotor and deviate partially from the sector mounted on the bottom of the fixed disc 2 to the first half of the grinding plates 5 , near the front disc, and another portion falls directly onto the second half of the grinding plates 5, near the disc hub.

One part of the fine abrasive coal dust moving with the hot drying gases under the action of aerodynamic forces is directed from the plane ring of the fixed disc 2 to the grinding plates adjacent to the disk hub, and another part deviates from the deflector deflector 3 to grinding plates adjacent to the front disc.

In this way, the abrasive coal dust is distributed more evenly over the entire surface of the grinding blades 5, thus avoiding local wear.

Claims (3)

1. A fan mill consisting of a housing-spiral housing a rotor comprising a front disc, a hub disk with radially mounted grinding plates, a door and a fixed detachable disc mounted thereto, characterized in that a deflector deflector (3) is attached to the fixed disc (2) in front of it. Fan mill according to claim 1, characterized in that the deflection deflector (3) consists of a part of a flat disk, a part of a cone and a part of a cylinder. Fan mill according to claim 1, characterized in that the deflection deflector (3) closes part of the inlet section of the rotor.