Cement vertical mill circulating bucket elevator screening device

Abstract

The utility model provides a circulating bucket elevator screening device of a cement vertical mill, which relates to the technical field of cement production, and comprises an obliquely arranged blanking piece, an ash bucket fixed with the blanking pipe and communicated with the blanking cavity, and an ash bucket arranged in the blanking piece and communicated with the ash bucket, and the blanking piece comprises a blanking pipe and a blanking cavity arranged in the blanking pipe and used for enabling powder to fall from the top end to the bottom end. The screen is mounted at the position, facing the opening of the discharging cavity, of the ash hopper in the inclined direction of the discharging cavity; when powder in the discharging cavity falls down, part of the powder falls into the ash hopper through the screen. The powder is screened through the screen, fine powder in the discharging pipe falls into the ash hopper through the screen, so that the amount of coarse powder is reduced, it is guaranteed that when the cement mill grinds the coarse powder again in the follow-up process, the running current of the mill is reduced, and therefore power consumption needed by grinding is reduced, and the cost needed by production is greatly reduced.

Description

TECHNICAL FIELD

[0001] The utility model relates to cement production technical field, concretely relates to a cement vertical mill circulating bucket lifting screening device. BACKGROUND

[0002] Cement vertical mill circulating bucket lifting usually refers to in the cement production process, using vertical mill carries out the powder grinding of material, and through the circulating conveying of bucket elevator (bucket lifting machine) to the powder grinding material, in this system, the function of bucket elevator is to lift the material of vertical mill powder grinding to a certain height, and the circulating bucket lifting discharges cement clinker, so as to subsequent full grinding.

[0003] At present, the powder produced by the existing cement vertical mill is directly discharged from the bottom powder outlet along the pipeline through the top powder inlet of the circulating bucket lifting downspout, as shown in the specific Figure 1 There are coarse powder and fine powder mixed in the powder, and the coarse powder and fine powder still need to be continuously ground, which leads to high mill running current, restricts the stable operation of the mill and the yield, increases the power consumption required by work, and improves the production cost. UTILITY MODEL CONTENT

[0004] To solve the above technical problems, the utility model installs the ash bucket through the downcomer, installs the screen mesh at the joint of the ash bucket and the downcomer, and screens the fine powder in the powder, and the specific technical scheme is as follows:

[0005] A cement vertical mill circulating bucket lifting screening device, comprising a downcomer and a downcomer cavity for powder falling from the top to the bottom inside the downcomer, and a bucket, which is fixed with the downcomer and communicates with the downcomer cavity; and a screen mesh is installed at the opening of the downcomer cavity towards the downcomer cavity along the inclined direction of the downcomer cavity; wherein when the powder falls in the downcomer cavity, part of the powder falls into the ash bucket through the screen mesh.

[0006] Preferably, the screen mesh comprises wear-resistant plates and mesh holes connected in sequence.

[0007] Preferably, the area of the mesh hole at the powder feeding end is at least greater than the area of the mesh hole at the powder feeding end.

[0008] Preferably, the mesh hole has a diameter of 0.6-1.2mm.

[0009] Preferably, the downcomer further comprises a downcomer ladder in contact with the powder.

[0010] Preferably, the middle part of the screen mesh is convex upwards, so that the screen mesh forms a broken line.

[0011] Preferably, the bottom end of the ash bucket is further provided with a discharging element for discharging the powder in the ash bucket.

[0012] From the above technical solutions, the utility model has the following beneficial effects:

[0013] The utility model discloses a dust collecting device for cement vertical mill, which comprises a feeding pipe, an ash bucket and a discharging pipe. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 It is a simple structure view of the existing technology of cement vertical mill circulating hopper lifting feeding chute;

[0015] Figure 2 It is a simple structure view of the utility model;

[0016] Figure 3 It is a cross section structure schematic view of the utility model;

[0017] Figure 4 It is a structure schematic view of the utility model screen.

[0018] In the drawing: 10, feeding element; 101, feeding pipe; 102, feeding cavity; 103, feeding ladder; 20, screen; 201, wear plate; 202, mesh; 30, ash bucket; 40, discharging pipe; 50, discharging element; 501, grid wheel; 502, motor. DETAILED DESCRIPTION

[0019] The utility model will be explained in detail in combination with the drawings and specific embodiments, and before explaining the technical scheme of each embodiment of the utility model in detail, the terms and names involved will be explained, in the specification, the components with the same name or the same number represent the similar or same structure, and are limited to the purpose of illustration.

[0020] As Figure 1 The existing technology directly circulates the powder for grinding by the circulating hopper lifting feeding chute, and the mill grinds the powder falling from the feeding chute again to meet the requirement of fine powder.

[0021] Through the continuous exploration and adjustment of the system, the mill operation is stable, P.042.5t / h, power consumption <23.0kwh / t, the average unit consumption of the machine body is 14.7kwh / t, the detection of V selected back powder is 55% of 1mm(1000um), which causes the mill circulating load to be too high, the main motor operating current is as high as 240-260A, which restricts the cement mill production and power consumption. It is expected that the circulating bucket lifting current will decrease by about 15A, the powder entering will be reduced through technical improvement, the mill back powder volume will decrease, the material layer will be relatively stable and the operating current will decrease by about 10A, it is expected that the cement vertical mill production will increase by 20t / h and the cement process power consumption will decrease by 2.0kwh / t.

[0022] The specific local plan for energy saving and consumption reduction is as follows:

[0023] As shown in Figure 2 and Figure 3 , a cement vertical mill circulating bucket lifting and screening device, comprising a tilting discharge member 10, which comprises a discharge pipe 101 and a discharge cavity 102 inside the discharge pipe 101 for powder to fall from the top to the bottom, and a bucket 30 fixed with the discharge pipe 101 and communicating with the discharge cavity 102; and a screen 20 installed at the opening of the discharge cavity 102 of the bucket 30 and arranged along the inclination direction of the discharge cavity 102; wherein when the powder in the discharge cavity 102 falls, part of the powder falls into the bucket 30 through the screen 20.

[0024] Wherein, the raw materials are processed by the cement mill, and the cement clinker falls from the top of the discharge pipe 101, the powder is discharged from the material port at the bottom of the discharge cavity 102, and at the same time, when the powder contacts the bottom of the discharge pipe 101, the powder will contact the screen 20 and part of the fine powder in the powder will be screened out through the screen 20, so that the fine powder falls into the bucket 30 through the screen 20, while the coarse powder falls along the slope of the screen 20 and falls out of the material port of the discharge pipe 101, that is, part of the fine powder in the powder is screened out through the screen 20, reducing the content of fine powder in the coarse powder during grinding, thereby saving the power consumption required during the operation of the mill and reducing the cost required for grinding.

[0025] As shown in Figure 3 and Figure 4 , the screen 20 comprises wear-resistant plates 201 and mesh holes 202 connected in turn, wherein the wear-resistant plates 201 contact the mesh holes 202, that is, the wear-resistant plates 201 can be connected with the discharge pipe 101 as the screen 20, or the mesh holes 202 can be connected with the discharge pipe 101 as the screen 20, so that the wear-resistant plates 201 can guide the coarse powder falling from the mesh holes 202.

[0026] As shown in Figure 3 and Figure 4As shown, the area of the mesh 202 at the powder discharge end is at least greater than the area of the mesh 202 at the powder feeding end, the lower mesh 202 can increase the contact area with the powder, and when the upper mesh 202 contacts the powder, it slows down the powder, so that when the powder falls on the lower mesh 202 again, the powder can stay on the lower mesh 202 until the subsequent powder pushes the powder on the lower mesh 202.

[0027] As another embodiment of the present application, different from the above, the middle part of the screen 20 is upwardly convex, so that the screen 20 forms a broken line, that is, the upper part is more gentle and the lower part is more steep. When the powder falls on the upper half of the screen 20, the powder can gradually stay on the mesh 202 of the upper half, so that the fine powder in the powder can pass through the screen 20 and fall into the hopper 30. Until the subsequent powder flushes the mesh 202 of the upper half, the powder that does not pass through the mesh 202 gradually falls to the lower half of the screen 20, so as to be screened again along the lower half of the screen 20 and then fall out of the discharge port of the discharge cavity 102. The flushed powder gradually and slowly stays on the upper half of the screen 20, so as to improve the screening effect of the mesh 202.

[0028] The aperture of the mesh 202 is 0.6-1.2mm, preferably the mesh 202 has an aperture of 0.9mm. The mesh 202 with an aperture of 0.9mm can ensure that most of the cement particles are below this size, which helps to improve the fineness of the cement and thus the strength and workability of the cement. The screen 20 with an aperture of 0.9mm can improve the production efficiency while ensuring the fineness of the cement. A too fine screen 20 can cause a decrease in screening speed and affect the production efficiency. The screen 20 with an aperture of 0.9mm is moderate, which can effectively screen out relatively coarse particles and will not cause the screen 20 to be blocked due to too small aperture, affecting the screening effect. It is selected and used considering many factors such as cement fineness, improved production efficiency, reduced equipment wear, compliance with industry standards and cost control.

[0029] As shown in Figure 2 and Figure 3 The discharge member 10 also has a discharge step 103 in contact with the powder, wherein the discharge step 103 is in contact with the powder, so that the powder falls gradually and avoids falling too fast, and also prevents the material from flushing and wearing the discharge pipe 101.

[0030] As shown in Figure 3 The bottom end of the hopper 30 is also provided with a discharge member 50, which is used to discharge the powder in the hopper 30. The discharge member 50 can adopt a valve, such as a butterfly valve, to discharge the powder in the hopper 30 by opening the valve. Meanwhile, a grading wheel 501 can also be used, preferably the grading wheel 501.

[0031] The discharge component 50 includes a dividing wheel 501 installed at the bottom of the ash hopper 30 and a motor 502 installed on one side of the dividing wheel 501. The motor 502 drives the star wheel inside the dividing wheel 501 to rotate, so as to ensure that the fine powder in the ash hopper 30 is discharged in a measured amount.

[0032] like Figure 3 As shown, the discharge end of the discharge component 50 is also equipped with a discharge pipe 40, which is connected to the ash hopper 30 and can transmit negative pressure to the ash hopper 30. The discharge pipe 40 can be connected to the main exhaust fan, which generates negative pressure to allow the fine powder to be discharged in accordance with the specified conditions. Figure 3 The middle arrow indicates the discharge, and the negative pressure can accelerate the falling of fine powder from the screen 20 into the ash hopper 30 to improve the screening effect and reduce the problem of material jamming. At the same time, combined with the dividing wheel 501, the ash hopper 30 can be airlocked for material discharge; the discharge pipe 40 can also be equipped with a screw conveyor to ensure the discharge of fine powder.

[0033] In practical use, cement clinker falls into the powder through the top of the feed pipe 101. The powder falls along the feed chamber 102 and slowly falls through the feed step 103. The powder is screened by the screen 20. The fine powder after screening falls into the ash hopper 30 through the screen 20, while the coarse powder that does not pass through the screen 20 is gradually discharged from the feed port along the feed step 103 to facilitate subsequent grinding. The fine powder in the ash hopper 30 is discharged by the dividing wheel 501. At the same time, the negative pressure accelerates the screening of fine powder by the screen 20. The fine powder is discharged through the discharge pipe 40, reducing the amount of coarse powder after feeding and reducing the energy consumption required for the cement mill to work.

[0034] The above-described embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made by those skilled in the art to the technical solutions of the present utility model without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A cement vertical mill circulating bucket elevator screening device, comprising a tilting arrangement (10) comprising a discharging pipe (101) and a discharging cavity (102) provided inside the discharging pipe (101) for powder to fall from the top end to the bottom end, characterized in that, Also comprising: a hopper (30) fixed with the feeding pipe (101) and communicating with the feeding cavity (102); and a screen (20) installed at the opening of the hopper (30) towards the feeding cavity (102) along the inclination direction of the feeding cavity (102); wherein when the powder in the feeding cavity (102) falls, part of the powder falls into the hopper (30) through the screen (20).

2. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 1, wherein, The screen (20) comprises wear plates (201) and meshes (202) connected in sequence.

3. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 2, wherein, The area of the meshes (202) at the powder feeding end is at least greater than that of the meshes (202) at the powder feeding end.

4. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 2, wherein, The aperture of the meshes (202) is 0.6-1.2mm.

5. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 1, wherein, The feeding device (10) is further provided with a feeding step (103) in contact with the powder.

6. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 1, wherein, The middle part of the screen (20) is convex upwards, so that the screen (20) forms a broken line.

7. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 1, wherein, The bottom end of the hopper (30) is further provided with a discharging device (50) for discharging the powder in the hopper (30).

8. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 7, wherein, The discharging device (50) comprises a grading wheel (501) installed at the bottom end of the hopper (30) and a motor (502) installed at one side of the grading wheel (501).

9. The cement vertical mill circulating bucket elevator screen apparatus as claimed in claim 7, wherein, The discharging end of the discharging device (50) is further provided with a discharging pipe (40) communicating with the hopper (30) and capable of transmitting negative pressure to the hopper (30).

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