A pilot gas supplementing and ash conveying system

Abstract

The application discloses a pilot air supplementing and dust conveying system, which comprises a pilot dust conveying valve, a dust conveying pipeline and a compressed air pipeline, a plurality of dust conveying valves are installed in parallel between the dust conveying pipeline and the compressed air pipeline, the dust conveying pipeline is communicated with valve outlets of the dust conveying valves through a plurality of branch passages, check valves are installed on the branch passages, the compressed air pipeline is communicated with valve inlets of the dust conveying valves through a plurality of air inlet branch pipes, a signal port A of a front dust conveying valve is communicated with a signal port B of a rear dust conveying valve through a pipeline, the signal port B of the first dust conveying valve is blocked, and the signal port A of a rearmost dust conveying valve is blocked. The application has the advantages of compact layout, convenient and fast use, accurate positioning of a blocking position, clean blowing of the blocking position by compressed air, triggering of valve work in front of a new blocking position when the blocking position is transferred, circular blowing, smoothness of a dust conveying pipeline, prevention of large air volume from entering, reduction of pipeline abrasion, and prolongation of the service life of the pipeline.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ash conveying system for thermal power plant, and particularly relates to a pilot air-supplying ash conveying system. BACKGROUND

[0002] The pneumatic ash conveying system of the thermal power plant generally conveys high-concentration material through the static pressure and dynamic pressure of compressed air according to the pneumatic conveying principle of gas-solid two-phase flow. This ash conveying mode has the problems of pipe blockage, abrasion and large air consumption, especially the problem of pipe blockage. If not handled in time, the ash in the ash hopper will accumulate, the flowability of the ash will become poor, and the temperature will further decrease, which will aggravate the accumulation of the ash material. The existing mode is to add compressed air to the ash conveying pipeline for air-supplying ash conveying. Because the pipe blockage position is uncertain, the air pressure is insufficient, the air consumption is large, and the air volume in the ash conveying pipeline increases, too large air volume will cause abrasion of the ash conveying pipeline. In general, the traditional pilot air-supplying ash conveying system continuously inputs compressed air into the pipeline. If the pipeline is blocked, the compressed air in the pipeline will unblock the blockage position of the dust. If there is no blockage phenomenon in the pipeline, the continuous input of compressed air will cause air waste and abrasion of the conveying pipeline. SUMMARY

[0003] The purpose of the present application is to provide a pilot air-supplying ash conveying system to solve the problems of pipe blockage, abrasion and large air consumption existing in the traditional pneumatic ash conveying.

[0004] To solve the above technical problems, the present application adopts the following technical scheme:

[0005] The pilot air-supplying ash conveying system comprises a pilot ash conveying valve, an ash conveying pipeline and a compressed air pipeline. A plurality of ash conveying valves are installed in parallel between the ash conveying pipeline and the compressed air pipeline. The ash conveying pipeline is communicated with the valve outlet of the ash conveying valve through a plurality of branch channels. A check valve is installed on the branch channel. The compressed air pipeline is communicated with the valve inlet of the ash conveying valve through a plurality of air inlet branch pipes. The signal port A of the front ash conveying valve is communicated with the signal port B of the adjacent rear ash conveying valve through a pipeline, and the signal port B of the first ash conveying valve is blocked, and the signal port A of the last ash conveying valve is blocked.

[0006] Further, the distance between the adjacent two ash conveying valves is not greater than 2 meters. The ash conveying valves are sequentially numbered as No. 1 valve, No. 2 valve, No. 3 valve, No. 4 valve, No. 5 valve and No. n valve. The number of the No. n valve is set according to the total length of the ash conveying pipeline.

[0007] Further, when the ash conveying pipeline between the first valve and the second valve is not blocked, the force of the two membrane covers of the first valve is equal, the valve core is pressed on the valve outlet under the action of the spring compression force and is in the closed state, and then the first valve and the second valve are in the stop working state; when the ash conveying pipeline between the first valve and the second valve is blocked, a pressure difference appears in the upper membrane cover and the lower membrane cover of the first valve, the pressure difference makes the valve core rise away from the valve outlet and is in the open state, the first valve starts to work, and air is supplemented to the front end of the blocked point through the compressed air pipeline, the air inlet branch pipe, the valve inlet, the valve outlet and the check valve and dredges the pipeline.

[0008] Further, the pilot type ash conveying valve comprises a valve core and a valve body, the valve core is arranged in the inner cavity of the valve body in an extendable manner, a lower membrane cover is connected to the top surface of the valve body, an upper membrane cover is arranged above the lower membrane cover, the lower membrane cover and the upper membrane cover are connected to form a hollow cavity, a rubber diaphragm is connected to the center position of the hollow cavity, the rubber diaphragm is connected to a limiting plate through a spring at the top, a limiting screw is arranged above the limiting plate, the screw rod of the limiting screw penetrates through the threaded hole of the upper membrane cover and abuts against the top surface of the limiting plate, the upper end surface of the valve core is bonded and connected to the rubber diaphragm, the valve inlet is arranged on one side surface of the valve body and is connected to the inner cavity of the valve body in a communication manner, the valve outlet is arranged on the bottom surface of the valve body and is connected to the inner cavity of the valve body in a communication manner, the lower membrane cover is connected to the valve outlet in a communication manner through an internal communication pipeline, and the valve inlet is connected to the valve outlet in a communication manner through a throttling channel.

[0009] Further, the signal port A is arranged on one side of the top surface of the upper membrane cover, the signal port B is arranged on one side of the bottom surface of the lower membrane cover, and the signal port A and the signal port B correspond to each other in an up-down manner.

[0010] Further, the periphery of the rubber diaphragm is tightly connected to the matching edges of the lower membrane cover and the upper membrane cover, and the rubber diaphragm divides the hollow cavity into two parts in an up-down manner.

[0011] Further, the two ends of the spring are positioned and connected to the opposite surfaces of the rubber diaphragm and the limiting plate.

[0012] Further, the valve core is connected to constitute a sealing head through a straight rod, the bottom side wall of the sealing head is arranged as a tapered surface, and the tapered surface is tightly pressed on the valve outlet.

[0013] Compared with the prior art, the beneficial technical effects of the present application are as follows:

[0014] The application is a pilot type air supplement and ash conveying system, which comprises a pilot type ash conveying valve, an ash conveying pipeline and a compressed air pipeline, a plurality of ash conveying valves are installed in parallel between the ash conveying pipeline and the compressed air pipeline, the signal port A of the front ash conveying valve is communicated with the signal port B of the rear adjacent ash conveying valve through a pipeline, the signal port B of the first ash conveying valve is blocked, and the signal port A of the last ash conveying valve is blocked; the ash conveying valves are sequentially numbered as a first valve, a second valve, a third valve, a fourth valve, a fifth valve and an n valve, and the number of the n valve is set according to the total length of the ash conveying pipeline; during work, taking the first valve and the second valve as an example, when the ash conveying pipeline between the first valve and the second valve is not blocked, the forces in the two diaphragm covers of the first valve are equal, the valve core is pressed on the valve outlet under the action of the spring compression force and is in a closed state, and then the first valve and the second valve are in a stop working state; when the ash conveying pipeline between the first valve and the second valve is blocked, a pressure difference will occur in the upper diaphragm cover and the lower diaphragm cover of the first valve, the pressure difference makes the valve core rise away from the valve outlet and is in an open state, the first valve starts to work, and air is supplemented to the front end of the blocked point through the compressed air pipeline, the air inlet branch pipe, the valve inlet, the valve outlet and the check valve to dredge the pipeline.

[0015] 1) The accuracy of positioning the ash conveying blockage position: compared with the traditional pipeline ash conveying system, the blocked position can be accurately positioned, when the ash conveying pipeline between adjacent ash conveying valves is not more than 2 meters, the valve before the blocked point starts to work, compressed air is blown into the ash conveying pipeline to dredge the pipeline.

[0016] 2) The time efficiency of removing the ash conveying blockage is greatly improved, the system automatically works according to the air pressure difference, can realize automatic monitoring and removal of pipeline blockage, and does not need manual inspection and operation.

[0017] 3) Energy saving, emission reduction and improvement of pipeline service life: the system only works at the valve before the blocked position, and the valves at other positions are in a silent state, which reduces unnecessary compressed air waste, reduces the wear caused by excessive air volume to the pipeline, and helps to improve the service life of the pipeline.

[0018] The application has compact layout, convenient and fast use, can accurately position the blocked position through the introduction of multiple pilot type ash conveying valves, the blocked point is cleaned by compressed air blowing, and when the blocked point is transferred, the valve before the new blocked point is triggered to work, and the pipeline is dredged to ensure the smoothness of the ash conveying pipeline, avoid the entry of large air volume, reduce the wear of the pipeline, and improve the service life of the pipeline. BRIEF DESCRIPTION OF DRAWINGS

[0019] The application will be further described in connection with the accompanying drawings.

[0020] Figure 1 The working principle diagram of the pilot air supply and ash conveying system of the application;

[0021] Figure 2 The structure diagram of the ash conveying valve of the application;

[0022] Reference signs: 1 - valve core; 2 - valve body; 3 - rubber diaphragm; 4 - lower diaphragm cover; 5 - upper diaphragm cover; 6 - spring; 7 - limiting screw; 8 - signal port A; 9 - signal port B; 10 - valve inlet; 11 - throttling passage; 12 - valve outlet; 13 - check valve; 14 - ash conveying pipeline; 15 - internal communication pipeline; 16 - compressed air pipeline;

[0023] 100 - ash conveying valve; 101 - first valve; 102 - second valve; 103 - third valve; 104 - fourth valve; 105 - fifth valve. DETAILED DESCRIPTION

[0024] As Figures 1-2 shown, a pilot air supply and ash conveying system includes a pilot ash conveying valve 100, an ash conveying pipeline 14 and a compressed air pipeline 16, a plurality of the ash conveying valves 100 are installed in parallel between the ash conveying pipeline 14 and the compressed air pipeline 16, the ash conveying pipeline 14 is communicated with the valve outlet 12 of the ash conveying valve 100 through a plurality of branch passages, the check valve 13 is installed on the branch passage, the compressed air pipeline 16 is communicated with the valve inlet 10 of the ash conveying valve 100 through a plurality of air inlet branch pipes; the signal port A 8 of the front ash conveying valve 100 is communicated with the signal port B 9 of the rear adjacent ash conveying valve 100 through a pipeline, and the signal port B 9 of the first ash conveying valve 100 is blocked, and the signal port A 8 of the last ash conveying valve 100 is blocked.

[0025] The distance between the adjacent two ash conveying valves 100 is not more than 2 meters, the ash conveying valves 100 are numbered in sequence as the first valve 101, the second valve 102, the third valve 103, the fourth valve 104, the fifth valve 105 and the n-th valve, and the number of the n-th valve is set according to the total length of the ash conveying pipeline 14.

[0026] When the ash conveying pipeline 14 between the first valve 101 and the second valve 102 is not blocked, the force of the two diaphragm covers of the first valve 101 is equal, the valve core 1 is pressed against the valve outlet 12 under the pressure of the spring 6 and is in a closed state, and the first valve 101 and the second valve 102 are in a stop working state; when the ash conveying pipeline 14 between the first valve 101 and the second valve 102 is blocked, a pressure difference will occur in the upper diaphragm cover and the lower diaphragm cover of the first valve 101, which makes the valve core rise away from the valve outlet 12 and be in an open state, and the first valve 101 starts to work, and air is supplemented to the front end of the blocked point through the compressed air pipeline 16, the air inlet branch pipe, the valve inlet 10, the valve outlet 12 and the check valve 13 to dredge the pipeline. When other positions are blocked, the unblocking method is the same as described above. Specifically, if the blocked point does not disappear after the last compressed air blowing, but shifts, a valve before the new blocked point will be triggered to work, and the cycle blowing is ensured to keep the ash conveying pipeline unblocked. The system only works when the ash conveying valve before the blocked position is in a working state, and the ash conveying valves at other positions are in a silent state, which reduces unnecessary waste of compressed air and reduces the wear of the pipeline caused by excessive air volume, thereby prolonging the service life of the pipeline.

[0027] Specifically, as shown in Figure 2 The pilot-controlled ash conveying valve 100 includes a valve core 1 and a valve body 2, the valve core 1 is telescopically arranged in the inner cavity of the valve body 2, a lower diaphragm cover 4 is connected to the top surface of the valve body 2, an upper diaphragm cover 5 is arranged above the lower diaphragm cover 4, the lower diaphragm cover 4 and the upper diaphragm cover 5 are connected to form a hollow cavity, a rubber diaphragm 3 is connected to the center position of the hollow cavity, the upper part of the rubber diaphragm 3 is connected to a limiting plate through a spring 6, a limiting screw 7 is arranged above the limiting plate, the screw rod of the limiting screw 7 penetrates through the threaded hole of the upper diaphragm cover 5 and abuts against the top surface of the limiting plate; the upper end surface of the valve core 1 is bonded and connected with the rubber diaphragm 3, a valve inlet 10 is arranged on one side surface of the valve body 2 and communicates with the inner cavity of the valve body 2, a valve outlet 12 is arranged on the bottom surface of the valve body 2 and communicates with the inner cavity of the valve body 2, the lower diaphragm cover 4 communicates with the valve outlet 12 through an internal communication pipeline 15, and the valve inlet 10 communicates with the valve outlet 12 through a throttling channel 11; specifically, the channel 11, the channel 15 and the pressure at the signal port B9 are equal, when the ash conveying pipeline 14 is blocked, the pressure difference makes the valve core 1 open, and a large amount of compressed gas is injected into the ash conveying pipeline 14 through the channel 12.

[0028] Signal port A8 is located on one side of the top surface of the upper membrane cover 5, and signal port B9 is located on one side of the bottom surface of the lower membrane cover 4, with signal port A8 and signal port B9 corresponding vertically. Specifically, signal port A8 on the previous ash conveying valve 100 is connected to signal port B9 on the next adjacent ash conveying valve 100 via a pipeline. That is, signal port A8 on valve 101 is connected to signal port B9 on valve 202 via a pipeline, signal port A8 on valve 202 is connected to signal port B9 on valve 303 via a pipeline, and so on up to valve n.

[0029] The periphery of the rubber diaphragm 3 is pressed tightly onto the mating edges of the lower membrane cover 4 and the upper membrane cover 5, and the rubber diaphragm 3 divides the hollow cavity into upper and lower parts.

[0030] The two ends of the spring 6 are positioned and connected to the opposite surfaces of the rubber diaphragm 3 and the limiting plate.

[0031] The valve core 1 is composed of a straight rod and a plug head. The bottom side wall of the plug head is set as a conical surface, and the conical surface is tightly pressed against the valve outlet 12.

[0032] In addition, multiple pressure monitoring devices, such as pressure gauges, can be installed on the ash conveying pipeline 14. Specifically, the pressure gauges can be evenly distributed on the ash conveying pipeline 14 and arranged at intervals with the ash conveying valve 100. The monitoring signals are transmitted to the control center, and the operators can visually monitor the unobstructed and blocked conditions of the entire ash conveying pipeline, thereby effectively ensuring the unobstructed flow of the entire ash conveying pipeline.

[0033] Working principle of pilot-operated ash conveying valve 100:

[0034] First, the pressure at valve inlet 10 is set as P1 and called valve inlet pressure, the pressure at valve outlet 12 is set as P2 and called valve outlet pressure, and the pressure in ash conveying pipeline 14 is set as P3 and called ash conveying pipeline pressure.

[0035] 1) When the ash conveying valve is closed, the valve inlet pressure P1 enters the valve through the throttling channel 11, causing the valve outlet pressure P2 to rise slowly. Since there is a check valve on the branch channel connected below the valve inlet, the valve outlet pressure P2 will eventually rise to a value equivalent to the ash conveying pipeline pressure P3.

[0036] 2) When a pressure difference is generated between signal port A and signal port B, the air pressure agitates the rubber diaphragm 3 to move upward, and the spring 6 compresses and drives the valve core 1 to rise, causing the valve outlet 12 to open. Compressed air enters the valve inlet 10 through the air inlet branch pipe, and then injects a large amount of compressed air into the ash conveying pipeline 14 through the valve outlet 12 and check valve 13 to complete the blockage clearing operation.

[0037] 3) When the pressure difference between signal port A and signal port B gradually equal, the rubber diaphragm 3 moves down, the spring 6 resets to extend, and drives the valve core 1 to close the valve outlet 12 first, stopping the compressed air injection into the ash conveying pipeline 14.

[0038] The above-described embodiments are merely preferred modes of the present application, and are not intended to limit the scope of the present application. Various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art without departing from the design spirit of the present application shall fall within the protection scope of the present application as defined by the claims.

Claims

1. A pilot operated air assisted ash injection system characterized by: The invention relates to a kind of compressed air control dust valve, including pilot dust valve (100), dust pipe (14) and compressed air pipe (16), a plurality of dust valve (100) are installed in parallel between the dust pipe (14) and the compressed air pipe (16), the dust pipe (14) is communicated with the valve outlet (12) of the dust valve (100) by a plurality of branch channels, check valve (13) is installed on the branch channel, the compressed air pipe (16) is communicated with the valve inlet (10) of the dust valve (100) by a plurality of air inlet branch pipes;The signal port A (8) of the front dust valve (100) is communicated with the signal port B (9) of the adjacent rear dust valve (100) by pipeline, and the signal port B (9) of the first dust valve (100) is blocked, and the signal port A (8) of the last dust valve (100) is blocked; The interval of adjacent two dust valves (100) is not more than 2 meters, and the dust valves (100) are numbered in sequence as No. 1 valve (101), No. 2 valve (102), No. 3 valve (103), No. 4 valve (104), No. 5 valve (105) to n valve, and the number of n valve is set according to the total length of dust pipe (14); When the dust pipe (14) between No. 1 valve (101) and No. 2 valve (102) does not block, the force of the two membrane covers of No. 1 valve (101) is equal, the valve core (1) is pressed on the valve outlet (12) under the pressure of spring (6) and is in closed state, then No. 1 valve (101) and No. 2 valve (102) are in stop working state; When the dust pipe (14) between No. 1 valve (101) and No. 2 valve (102) blocks, a pressure difference will appear in the upper membrane cover and the lower membrane cover of No. 1 valve (101), the pressure difference makes the valve core rise away from the valve outlet (12) and be in open state, No. 1 valve (101) starts to work, air is supplemented through the compressed air pipe (16), air inlet branch pipe, valve inlet (10), valve outlet (12) and check valve (13) to the front end of the block point and dredges the pipeline; The pilot type ash conveying valve (100) comprises a valve core (1) and a valve body (2), the valve core (1) is telescopically arranged in the inner cavity of the valve body (2), the top surface of the valve body (2) is connected with a lower membrane cover (4), the upper side of the lower membrane cover (4) is provided with an upper membrane cover (5), the lower membrane cover (4) and the upper membrane cover (5) are connected to form a hollow cavity, the center position of the hollow cavity is connected with a rubber diaphragm (3), the upper side of the rubber diaphragm (3) is connected with a limiting plate through a spring (6), the upper side of the limiting plate is provided with a limiting screw (7), the screw rod of the limiting screw (7) penetrates the threaded hole of the upper membrane cover (5) and abuts against the top surface of the limiting plate, the upper end surface of the valve core (1) is adhesively connected with the rubber diaphragm (3), the valve inlet (10) is arranged on one side surface of the valve body (2) and is connected with the inner cavity of the valve body (2), the valve outlet (12) is arranged on the bottom surface of the valve body (2) and is connected with the inner cavity of the valve body (2), the lower membrane cover (4) is connected with the valve outlet (12) through an internal communication pipeline (15), and the valve inlet (10) is connected with the valve outlet (12) through a throttling channel (11).

2. Pilot gas injection system according to claim 1, characterized in that The signal port A (8) is arranged on one side of the top surface of the upper membrane cover (5), the signal port B (9) is arranged on one side of the bottom surface of the lower membrane cover (4), and the signal port A (8) and the signal port B (9) correspond to each other in up-down direction.

3. The pilot operated air assisted dust delivery system of claim 1, wherein: The periphery of the rubber diaphragm (3) is press-connected on the matching edges of the lower membrane cover (4) and the upper membrane cover (5), and the rubber diaphragm (3) divides the hollow cavity into two parts in up-down direction.

4. The pilot gas injected pulverized coal firing system as claimed in claim 1 wherein: The two ends of the spring (6) are positioned and connected on the opposite surfaces of the rubber diaphragm (3) and the limiting plate.

5. The pilot gas injected pulverized coal firing system as claimed in claim 1 wherein: The valve core (1) is connected to form a straight rod and a plugging head, the bottom side wall of the plugging head is provided as a tapered surface, and the tapered surface is tightly pressed on the valve outlet (12).

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