Coal mill air ring device suitable for discharging mud and sand sundries in coal

Abstract

The utility model discloses a coal mill air ring device suitable for discharging mud and sand sundries in coal, which comprises a coal mill barrel, a static ring fixedly mounted in the coal mill barrel, a polishing barrel arranged in the static ring, a movable ring mounted on the outer side of the polishing barrel, and an air blocking ring mounted on the outer side of the movable ring. Self-adjusting type axial sealing baffles are installed at the bottom end between the air blocking ring and the static ring, a sediment discharging channel is formed in the middle between the air blocking ring and the static ring, each self-adjusting type axial sealing baffle comprises a plurality of blades and a limiting piece, the middle of each limiting piece is fixedly connected with one end of the corresponding blade, and each limiting piece comprises two limiting shaft seats and an adjusting shaft. The structure of the air ring of the coal mill is designed, an impurity discharging device capable of automatically discharging mud and sand is additionally arranged, meanwhile, the sealing performance of the air ring of the coal mill is improved, the air leakage amount of the air ring of the coal mill is reduced, and finally the purposes of achieving stable operation of the coal mill and improving the output of the coal mill are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of coal mills, in particular to a coal mill air ring device suitable for discharging mud, sand and other impurities in coal. Background Art

[0002] The working principle of the medium-speed coal mill is that the hot air flowing in opposite directions at the throat of the wind ring collides violently with the falling stone coal, which holds or blows up a large amount of coal with lower density, separates and blows up the fine coal powder, and then enters the coal powder pipeline after further separation through the separator.

[0003] When the coal mill air ring works normally, impurities such as stone coal that are not ground are thrown to the throat of the air ring. When the hot air from bottom to top is not enough to prevent them from falling, the stone coal falls into the stone coal box through the air ring.

[0004] However, traditional coal mills have the following disadvantages:

[0005] At present, due to the great changes in coal quality in various power plants, the mud and sand content in coal has increased. The hot air from the bottom up will blow up some of the mud and sand. The suspended sand layer affects the coal powder separation efficiency and causes insufficient output of the pulverizer. In order to solve the problem of suspended sand, the pressure difference must be changed and the pulverizer needs to be thrown out multiple times a day. Otherwise, it will cause clogging, which will directly affect the safe and stable operation of the boiler. Summary of the invention

[0006] The utility model aims to provide a coal mill air ring device suitable for discharging mud, sand and other impurities in coal, so as to solve the problem raised in the above-mentioned background technology that the coal quality in various power plants varies greatly, the mud and sand content in the coal increases, the hot air from bottom to top will blow up part of the mud and sand, and the suspended sand layer affects the coal powder separation efficiency, resulting in insufficient coal mill output; in order to solve the problem of sand suspension, the pressure difference must be changed, and the mill needs to be thrown out multiple times a day, otherwise it will cause mill blockage, which directly affects the safe and stable operation of the boiler.

[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a coal mill air ring device suitable for discharging mud, sand and debris in coal, comprising a coal mill cylinder, a static ring is fixedly installed inside the coal mill cylinder, a dynamic ring is arranged inside the static ring, a wind shield ring is installed on the outer side of the dynamic ring, a self-adjusting axial sealing baffle is installed at the bottom end between the wind shield ring and the static ring, a mud and sand discharge channel is opened in the middle part between the wind shield ring and the static ring, two of the self-adjusting axial sealing baffles each include a plurality of blades and a limit member, the middle part of the limit member is fixedly connected to one end of the blade, the limit member includes two limit shaft seats and an adjusting shaft, and the opposite ends of the two limit shaft seats are respectively fixedly connected to the two ends of the adjusting shaft.

[0008] As a preferred technical solution of the utility model, the middle part of the adjusting shaft is fixedly connected to the blade, the top end of the limiting shaft seat is fixedly connected to the side opposite to the static ring, and the self-adjusting axial sealing baffle is installed on the static ring through the limiting shaft seat.

[0009] As a preferred technical solution of the utility model, the blade is located below the static ring, and one side of the top end of the blade is in contact with the side directly facing the wind shield ring.

[0010] When the weight of the accumulated sediment is greater than the lifting pressure generated by the hot air blowing upward, the blades in the self-adjusting axial sealing baffle deflect relative to the wind shield ring, thereby opening the self-adjusting axial sealing baffle and letting the sediment fall out. After the sediment falls out, the lifting pressure of the hot air blowing upward is greater than the deadweight of the blades of the self-adjusting axial sealing baffle, thereby lifting the blades to reset and closing the self-adjusting axial sealing baffle.

[0011] Compared with the prior art, the beneficial effects of the utility model are:

[0012] The coal mill air ring structure is designed to add automatic mud and sand removal devices. At the same time, the sealing performance of the coal mill air ring is improved to reduce the air leakage of the coal mill air ring, ultimately achieving the goal of stable operation of the coal mill and improving the coal mill output. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is the internal schematic diagram of the coal mill cylinder of the utility model;

[0014] Figure 2 It is a cross-sectional view of the cylinder of the coal mill of the utility model;

[0015] Figure 3 It is an enlarged schematic diagram of D of the utility model;

[0016] Figure 4 It is a partial schematic diagram of the utility model;

[0017] Figure 5 It is a side view of the self-adjusting axial sealing baffle of the utility model;

[0018] In the figure: 1. Coal mill cylinder; 2. Self-adjusting axial sealing baffle; 3. Moving ring; 4. Static ring; 5. Mud and sand discharge channel; 6. Wind shield ring; 7. Limit shaft seat; 8. Adjusting shaft; 9. Blade; 11. Limit part. DETAILED DESCRIPTION

[0019] The following will be combined with the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0020] See also Figure 1-5 The utility model provides a coal mill air ring device suitable for discharging mud, sand and other debris in coal, comprising a coal mill cylinder 1, a static ring 4 is fixedly installed inside the coal mill cylinder 1, a dynamic ring 3 is arranged inside the static ring 4, a wind shield ring 6 is arranged on the outer side of the dynamic ring 3, a self-adjusting axial sealing baffle 2 is installed at the bottom end between the wind shield ring 6 and the static ring 4, a mud and sand discharge channel 5 is opened in the middle between the wind shield ring 6 and the static ring 4, two self-adjusting axial sealing baffles 2 each include a plurality of blades 9 and a limit member 11, the middle part of the limit member 11 is fixedly connected to one end of the blade 9, the limit member 11 includes two limit shaft seats 7 and an adjusting shaft 8, and the opposite ends of the two limit shaft seats 7 are fixedly connected to the two ends of the adjusting shaft 8 respectively.

[0021] The middle of the adjusting shaft 8 is fixedly connected to the blade 9 , the top of the limiting shaft seat 7 is fixedly connected to the side directly opposite to the static ring 4 , and the self-adjusting axial sealing baffle 2 is installed on the static ring 4 through the limiting shaft seat 7 .

[0022] The blade 9 is located below the stationary ring (4), and one side of the top of the blade 9 contacts the side opposite to the wind shield ring 6. When the weight of the accumulated mud and sand is greater than the lifting pressure generated by the hot air blowing upward, the blades in the self-adjusting axial sealing baffle are deflected relative to the wind shield ring, thereby opening the self-adjusting axial sealing baffle and allowing the mud and sand to fall out. After the mud and sand fall out, the lifting pressure of the hot air blowing upward is greater than the deadweight of the blades of the self-adjusting axial sealing baffle, thereby lifting the blades to reset and closing the self-adjusting axial sealing baffle.

[0023] In the utility model, a circle of wind shield ring 6 is added on the outer side of blades 9 on the moving ring 3 of coal mill wind ring, and a certain gap is left radially between wind shield ring 6 and static ring 4 of coal mill wind ring as a discharge channel for debris such as mud and sand, with a spacing of 6-9mm to achieve circumferential sealing, and a self-adjusting axial sealing baffle 2 is newly designed and installed on the lower inner side of static ring 4. When coal mill starts to run, due to the wind pressure of the wind chamber at the bottom inlet of coal mill, the gap self-adjusting axial sealing baffle 2 is in a closed state, and the axial spacing between self-adjusting axial sealing baffle 2 and the inlet edge of moving wind shield ring 6 of coal mill wind ring is 2-3mm, so as to achieve axial sealing, which can reduce the flow of primary air directly entering the grinding area and mixing with coal powder without being adjusted by wind ring device, and when the working grinding disc of coal mill rotates Mud, sand and other debris are blown over the nozzle of the moving ring 3 by the centrifugal force to the outer edge of the moving ring of the coal mill wind ring and enter the gap. Mud, sand and other impurities are guided to the gap by the baffle of the static ring 4. Mud, sand and other debris enter the gap by their own weight and begin to settle. When the sedimentation weight of mud, sand and other debris is greater than the wind lifting pressure at the inlet of the axial sealing baffle of the gap of the wind chamber at the bottom of the coal mill, the sealing baffle opens downward, and mud, sand and other debris are discharged from the gap channel and directly enter the wind chamber at the bottom of the coal mill and are discharged from the coal mill through the gravel coal system, so that mud, sand and other debris in the coal mill are discharged in time and quickly, solving the problem of suspension of mud, sand and other debris in the coal mill and realizing safe and stable operation of the coal mill. After mud, sand and other debris are discharged in time and quickly, they are self-adjustable under the action of the wind lifting pressure at the inlet of the bottom wind chamber. The sealing baffle 2 is lifted up and closed to realize the periodic discharge of mud, sand and other debris from the coal mill, which solves the problem that mud, sand and other debris can only be removed when the coal mill stops running, ensuring the continuous and efficient operation of the coal mill. Mud, sand and other debris can slide down along the gap discharge channel and accumulate in the gap discharge channel with the self-adjusting axial sealing baffle 2 as the "bottom". The self-adjusting gap sealing baffle and the adjustable axial sealing baffle are provided with a limiting device, including a limiting shaft seat 7 and an adjusting shaft 8. The self-adjusting axial sealing baffle 2 can be opened at an angle of 0°-60°. The self-adjusting axial sealing baffle 2 is composed of 12-36 blades 9, each blade 9 is equipped with a corresponding limiting device, and the limiting member 11 is composed of a limiting shaft seat 7 with a groove and an adjusting shaft 8 with an end block. 9 is flipped, the groove of the limiting shaft seat 7 limits the rotation angle of the stop block of the adjusting shaft 8 to control the opening of the baffle, and the self-adjusting axial sealing baffle 2 realizes the opening and closing of the baffle according to the weight of mud and sand and the inlet wind lifting pressure difference. When the weight of mud and sand is greater than the inlet wind lifting pressure, the baffle is opened; when the weight of mud and sand is less than the inlet wind lifting pressure, the baffle is closed. When the self-adjusting axial sealing baffle 2 is in a closed state, the self-adjusting axial sealing baffle 2 returns to a horizontal position, and the limiting cooperation with the static ring 4 and the limiting shaft seat 7 can ensure the matching clearance between the self-adjusting axial sealing baffle 2 and the moving ring 3, ensuring that there is no scratch with the moving ring 3 during operation, thereby increasing the primary air flow adjusted by the air ring device and improving the pulverizing efficiency of the coal mill.

[0024] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art may still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims

1. A coal mill air ring device suitable for discharging mud and sand in coal, comprising a coal mill cylinder (1), characterized in that: A stationary ring (4) is fixedly installed inside the coal mill cylinder (1), a dynamic ring (3) is arranged inside the stationary ring (4), a wind shield ring (6) is installed on the outer side of the dynamic ring (3), a self-adjusting axial sealing baffle (2) is installed at the bottom end between the wind shield ring (6) and the stationary ring (4), a sediment discharge channel (5) is opened in the middle between the wind shield ring (6) and the stationary ring (4), two self-adjusting axial sealing baffles (2) each include a plurality of blades (9) and a stopper (11), the middle of the stopper (11) is fixedly connected to one end of the blade (9), the stopper (11) includes two stopper shaft seats (7) and an adjusting shaft (8), and opposite ends of the two stopper shaft seats (7) are respectively fixedly connected to two ends of the adjusting shaft (8).

2. A coal mill air ring device suitable for discharging mud and sand in coal according to claim 1, characterized in that: The middle portion of the adjusting shaft (8) is fixedly connected to the blade (9), and the top end of the limiting shaft seat (7) is fixedly connected to a side directly opposite to the stationary ring (4).

3. A coal mill air ring device suitable for discharging mud and sand in coal according to claim 1, characterized in that: The blade (9) is located below the stationary ring (4), and one side of the top end of the blade (9) is in contact with a side of the wind shield ring (6) that is directly opposite to the top end.

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