Sealing air connecting structure of coal drop pipe

Abstract

The utility model provides a coal drop pipe sealing air connecting structure which comprises an inclined coal drop pipe, an original air pipe installed at the right upper end of the bottom side of the inclined coal drop pipe, a connecting air pipe connected to the tail end of the original air pipe, a straight coal drop pipe installed at the top end of the inclined coal drop pipe, a sealing air pipe connected to the right end of the straight coal drop pipe in an inclined mode, and a connecting air pipe connected to the tail end of the sealing air pipe. The front end of the connecting air pipe is connected with an air outlet mother pipe. According to the sealing air connecting structure of the coal drop pipe, by arranging the sealing air pipe and other structures, the effects of preventing coal powder from being blocked in the coal drop pipe and reducing the possibility that smoke flows backwards can be achieved.

Description

Technical Field

[0001] This utility model relates to the field of circulating fluidized bed boiler technology, and more specifically, to a sealing air connection structure for a coal chute. Background Technology

[0002] The smoothness of coal feeding in a circulating fluidized bed boiler is a major factor affecting boiler operation. There are two main coal feeding methods: belt conveyor feeding and screw feeder feeding. The boiler originally used a screw feeder, but due to frequent hopper blockage, it was later switched to belt conveyor feeding. Belt conveyor feeding relies on the gravity of the pulverized coal, supplemented by hot air and coal spreading air (hot air) to deliver the pulverized coal into the furnace. To prevent high-temperature flue gas from the combustion chamber from backflowing into the feeder, the primary air cooling air is connected to the lower rear side of the feeder housing for sealing purposes; this air path is also called sealing air. However, existing technology has the following problems:

[0003] (1) When the furnace load increases to more than 38t / h, the flue gas inside the furnace exhibits a severe backflow phenomenon. The sealing air does not play a role, and the problem cannot be solved by adjusting the induced draft.

[0004] (2) The coal drop pipe is too large, and the sealing air and coal supply air cannot fill the cross section of the coal drop pipe, causing the flue gas in the furnace to backflow to the part with low cross section air pressure.

[0005] (3) When the primary air pressure in the furnace is greater than the combined force of the air pressure at the weak point of the coal drop pipe sealing air, the air pressure at the weak point of the coal delivery air, and the gravity of the coal powder in the sealing air gap (i.e. improper air pressure distribution), the phenomenon of flue gas backflow in the furnace will occur.

[0006] This invention can prevent coal dust from clogging the coal chute and reduce the possibility of flue gas backflow. Utility Model Content

[0007] The present invention aims to solve the technical problems mentioned in the background art and provide a sealing air connection structure for a coal chute, so as to prevent coal dust from clogging in the coal chute and reduce the possibility of flue gas backflow.

[0008] To achieve the above objectives, this utility model provides the following technical solution: a sealing air connection structure for a coal chuting pipe, comprising: an inclined coal chuting pipe, wherein an original air duct is installed at the upper right end of the bottom side of the inclined coal chuting pipe, a connecting air duct is connected to the end of the original air duct, a straight coal chuting pipe is installed at the top of the inclined coal chuting pipe, a sealing air duct is obliquely connected to the right end of the straight coal chuting pipe, a connecting air duct is connected to the end of the sealing air duct, and an air outlet main pipe is connected to the front end of the connecting air duct.

[0009] A further preferred embodiment: the angle of the oblique connection between the sealed air duct and the coal drop pipe is 30°, and the angle of the oblique coal drop pipe and the straight coal drop pipe is 40°.

[0010] A further preferred embodiment: a second gate valve is installed at the top of the connecting duct where it connects to the main air outlet.

[0011] A further preferred embodiment: A first gate valve is installed at the right end of the sealed air duct where it connects to the connecting air duct.

[0012] A further preferred embodiment: There are two sets of inclined coal drop pipe, original air pipe and sealing air pipe, which are installed on the left and right sides of the connecting air pipe respectively. After the sealing air pipe is led to the coal drop pipe, it splits into two paths and enters the straight coal drop pipes on both sides respectively.

[0013] A further preferred embodiment: hangers are provided at the bends of the original air duct, the sealed air duct, and the connecting air duct.

[0014] A further preferred embodiment: a metal flexible hose is installed on the inclined pipe connecting the sealed air duct and the straight coal drop pipe.

[0015] A further preferred embodiment: the original air duct extends into the center of the inclined coal drop pipe, and the original air duct has a bend parallel to the inclined coal drop pipe at the center of the inclined coal drop pipe.

[0016] Beneficial effects:

[0017] 1. By setting up a sealed air duct, the effect of preventing coal dust from clogging in the coal drop pipe is achieved. After the air is heated by the air preheater, it is connected to the sealed air duct through the connecting air duct and blown into the direct coal drop pipe from the sealed air duct to heat the coal dust and prevent the coal dust from clogging in the coal drop pipe when there is a lot of external moisture in the coal dust.

[0018] 2. By setting up sealed air ducts, the possibility of flue gas backflow can also be reduced. The air supplied to the direct coal pipe not only increases the total air pressure but also the total air volume, enhances the sealing effect of the air, effectively reduces the possibility of flue gas backflow, and expands the range of air action, reducing the space for flue gas backflow in the furnace, further reducing the possibility of flue gas backflow.

[0019] 3. In summary, this type of sealed air connection structure for coal chutes, by incorporating sealed air ducts and other structures, can prevent coal dust from clogging the coal chutes and reduce the possibility of flue gas backflow. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall three-dimensional structure of this utility model.

[0021] Figure 2 This is a front view structural diagram of the present invention.

[0022] Figure 3 This is a schematic diagram of the inclined coal drop pipe, the straight coal drop pipe, and the sealed air duct of this utility model.

[0023] Figure 4 This is a cross-sectional view of the inclined coal drop pipe and the original air duct of this utility model.

[0024] Figure 1-4 In the middle: 1. Inclined coal drop pipe; 2. Original air duct; 3. Metal flexible hose; 4. Sealed air duct; 5. First gate valve; 6. Straight coal drop pipe; 7. Connecting air duct; 8. Hanger; 9. Second gate valve; 10. Main air outlet pipe. Detailed Implementation

[0025] The following will refer to the appendix in the embodiments of this utility model. Figure 1-Figure 4 The technical solutions in the embodiments of this utility model will be clearly and completely described.

[0026] Please see Figure 1-4 In this embodiment of the utility model, a sealing air connection structure for a coal chuting pipe includes: an inclined coal chuting pipe 1, which is installed at the upper right end of the bottom side for continuing to transport coal; an original air duct 2 connected to the upper right end of the bottom side of the inclined coal chuting pipe 1 for transporting air; a connecting air duct 7 connected to the end of the original air duct 2 to guide air to the coal chuting pipe; a straight coal chuting pipe 6 installed at the top of the inclined coal chuting pipe 1 for transporting coal; a sealing air duct 4 obliquely connected to the right end of the straight coal chuting pipe 6 for sealing the inside of the system and transporting air; and an outlet air duct 10 connected to the front end of the connecting air duct 7 for transporting air.

[0027] In this embodiment of the utility model, the oblique angle between the sealed air duct 4 and the coal drop pipe is 30°, and the oblique angle between the inclined coal drop pipe 1 and the straight coal drop pipe 6 is 40°. By obliquely connecting the sealed air duct 4 and the coal drop pipe, the effect of preventing coal from entering the sealed air duct 4 is achieved. By obliquely connecting the inclined coal drop pipe 1 and the straight coal drop pipe 6, the effect of allowing coal to enter the inclined coal drop pipe 1 and move along the inclined coal drop pipe 1 is achieved.

[0028] In this embodiment of the utility model, a second gate valve 9 is installed at the top of the connecting air duct 7 where it connects to the air outlet main pipe 10, so as to facilitate the later inspection and maintenance of the connecting air duct 7.

[0029] In this embodiment of the utility model, a first gate valve 5 is installed at the right end of the sealed air duct 4 where it connects to the connecting air duct 7, so as to facilitate the later inspection and maintenance of the sealed air duct 4 and the adjustment of air volume.

[0030] In this embodiment of the utility model, there are two sets of inclined coal drop pipe 1, original air pipe 2 and sealed air pipe 4, which are respectively installed on the left and right sides of the connecting air pipe 7. After the sealed air pipe 4 is led to the coal drop pipe, it splits into two paths and enters the straight coal drop pipes 6 on both sides, thereby improving the supply of one section of connecting air pipe 7 to two coal drop pipes and improving work efficiency.

[0031] In this embodiment of the utility model, hangers 8 are provided at the bends of the original air duct 2, the sealed air duct 4, and the connecting air duct 7 to achieve the effect of evenly suspending the sealed air duct 4; in addition, sliding supports are provided at appropriate positions to achieve the effects of guidance and vibration prevention.

[0032] In this embodiment of the invention, a metal flexible hose 3 is installed on the inclined pipe connecting the sealed air duct 4 and the straight coal drop pipe 6 to absorb the possible expansion of the sealed air duct 4.

[0033] In this embodiment of the utility model, the original air duct 2 extends into the center of the inclined coal drop pipe 1. The original air duct 2 has a bend parallel to the inclined coal drop pipe 1 at the center of the inclined coal drop pipe 1, so as to achieve the effect of blowing the air out parallel from the center of the inclined coal drop pipe 1, thereby better conveying coal.

[0034] Working principle: During operation, the belt conveyor transports coal to the straight coal drop pipe 6, then from the straight coal drop pipe 6 into the inclined coal drop pipe 1, and finally into the boiler along the inclined coal drop pipe 1. At the rear end of the inclined coal drop pipe 1, the original air duct 2 is connected, which supplies air into the inclined coal drop pipe 1 to assist the coal in entering the boiler. At the same time, the device has a new sealed air duct 4 connected obliquely to the right end of the straight coal drop pipe 6. After the air is heated by the air preheater, it is connected to the sealed air duct 4 through the connecting air duct 7 and blown into the straight coal drop pipe 6 to heat the pulverized coal. This prevents the pulverized coal from clogging the coal drop pipe if there is a lot of moisture on the outside. In addition, supplying air to the straight coal drop pipe 6 not only increases the total air pressure but also the total air volume, enhances the sealing effect of the air, effectively reduces the possibility of flue gas backflow, and fills the effective range of the air, reducing the space for flue gas backflow in the furnace, further reducing the possibility of flue gas backflow.

Claims

1. A sealing air connection structure for a coal chute, comprising: The inclined coal drop pipe (1) is characterized in that: an original air pipe (2) is installed at the upper right end of the bottom side of the inclined coal drop pipe (1), a connecting air pipe (7) is connected to the end of the original air pipe (2), a straight coal drop pipe (6) is installed at the top of the inclined coal drop pipe (1), a sealing air pipe (4) is obliquely connected to the right end of the straight coal drop pipe (6), a connecting air pipe (7) is connected to the end of the sealing air pipe (4), and an air outlet main pipe (10) is connected to the front end of the connecting air pipe (7).

2. The sealing air connection structure for a coal chute according to claim 1, characterized in that: The angle between the sealed air duct (4) and the coal drop pipe is 30°, and the angle between the inclined coal drop pipe (1) and the straight coal drop pipe (6) is 40°.

3. The sealing air connection structure for a coal chute according to claim 1, characterized in that: The connecting duct (7) has a second gate valve (9) installed at the top of the connection to the outlet main duct (10).

4. The sealing air connection structure for a coal chute according to claim 1, characterized in that: The sealed air duct (4) has a first gate valve (5) installed at the right end where it connects to the connecting air duct (7).

5. The sealing air connection structure for a coal chute according to claim 4, characterized in that: There are two sets of inclined coal drop pipe (1), original air pipe (2) and sealed air pipe (4), which are installed on the left and right sides of the connecting air pipe (7) respectively. After the sealed air pipe (4) is led to the coal drop pipe, it splits into two paths and enters the straight coal drop pipes (6) on both sides respectively.

6. The sealing air connection structure for a coal chute according to claim 1, characterized in that: Hangers (8) are provided at the bends of the original air duct (2), the sealed air duct (4) and the connecting air duct (7).

7. The sealing air connection structure for a coal chute according to claim 1, characterized in that: A metal flexible hose (3) is installed on the inclined pipe connecting the sealed air duct (4) and the straight coal drop pipe (6).

8. The sealing air connection structure for a coal chute according to claim 1, characterized in that: The original air duct (2) extends into the center of the inclined coal drop pipe (1), and the original air duct (2) has a bend parallel to the inclined coal drop pipe (1) at the center of the inclined coal drop pipe (1).

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