CN105781608B - Dual-reaction chamber preheats the automatically controlled adjustable type intake and exhaust flow guide system of catalytic oxidizing equipment - Google Patents

Abstract

The invention relates to an electronically controlled and adjustable intake and exhaust diversion system for a preheating catalytic oxidation device with double reaction chambers, comprising an intake main pipe, an intake branch pipe, an intake flaring pipe, two intake chambers, and two side-by-side reaction chambers. Chamber, exhaust cavity and exhaust manifold. A first deflector is arranged in the air intake flaring pipe, a second deflector is arranged in the air intake chamber, and a third deflector is arranged in the exhaust chamber. A PLC is added, a set of first electric control regulating mechanism is added on the outer wall of each air intake flared pipe, and a set of second electric control regulating mechanism is added on the side wall of each air intake cavity. The rotation of the first deflector in the air intake flaring pipe is regulated and controlled by the first electric control adjustment mechanism, and the rotation of the second deflector in the air intake chamber is regulated and controlled by the second electric control adjustment mechanism. The invention can flexibly adjust the angle of the deflector plate under the actual working condition where the air intake volume fluctuates greatly, so as to ensure the uniform distribution of the air intake volume and temperature of the oxidation bed, and improve the reliability of the device operation and the oxidation rate of the exhaust gas.

Description

Electronically controlled adjustable intake and exhaust diversion system for double reaction chamber preheating catalytic oxidation device

technical field

The invention specifically relates to an electronically controlled adjustable intake and exhaust diversion system of a double reaction chamber preheating catalytic oxidation device, which belongs to the technical field of coal mine ventilation gas utilization.

Background technique

In order to improve safety during coal mine production, a large amount of ventilation is usually used to discharge coal mine gas (called mine ventilation, Ventilation Air Methane, referred to as VAM). Methane is the main component of coal mine gas and many industrial waste gases. It is the second largest greenhouse gas after carbon dioxide, but it is also a high-quality and clean gas energy source. my country is a large coal-producing country, and more than 20 billion cubic meters of pure methane are emitted through the exhaust air of coal mines every year, which not only causes a huge waste of non-renewable energy resources, but also seriously pollutes the atmospheric environment.

The volume concentration of exhaust air gas is very low (generally 0.1% to 0.75%), and the fluctuating range of air volume and volume concentration determines that it is difficult to use traditional burners for direct combustion. Shandong University of Technology proposed the preheating catalytic oxidation technology. The reaction chamber uses a honeycomb ceramic oxidation bed loaded with precious metal catalysts to effectively catalyze the oxidation of coal mine exhaust air. Feedback to achieve a thermal equilibrium state maintained by self-heating. The oxidation temperature field of this technology is stable and reliable, and the heat recovery rate is high, the structure is compact, and the flow resistance is small, which is very economical and feasible. The uniformity of temperature distribution in the reaction chamber has an important impact on the stable operation of the preheating catalytic oxidation device. Uneven temperature distribution can cause local low temperature and flameout; or local high temperature can form a temperature gradient, resulting in thermal stress, deformation and destruction of the oxidation bed; High will also destroy the stability of the catalyst, leading to a decrease in catalyst activity or even disappear. As the exhaust air treatment capacity of the preheating catalytic oxidation device continues to increase, the volume and cross-sectional area of the reaction chamber continue to increase, and the temperature balance of the cross-section becomes more and more important. The air intake diversion system is a key part of the air intake flow distribution in the preheating catalytic oxidation device, which can ensure that the exhaust air oxidation heat release in the reaction chamber is also distributed evenly, and is conducive to improving the temperature balance of the oxidation bed cross section and the methane conversion of the device. rate is important.

Chinese patent document CN201110089161.9 provides an intake and exhaust guide device for a coal mine exhaust air preheating catalytic oxidizer, including an intake main pipe, an intake branch pipe, an intake flared pipe, an intake distribution bellows, a reaction chamber, an exhaust The air collecting box, exhaust shrinking pipe, exhaust branch pipe and exhaust main pipe are equipped with deflectors in the air intake flared pipe, air intake distribution bellows, exhaust collecting box and exhaust shrinking pipe, so that the exhaust air The distribution on the flow section in the catalytic reaction chamber is even, which reduces the flow resistance of the intake air. However, there are still deficiencies in this technical solution. The angle of the deflector cannot be adjusted flexibly during the operation of the device. The cross-section of the reaction chamber maintains a good temperature balance. In addition, the number of deflectors arranged is small, which cannot achieve a good flow diversion effect, and has a limited effect on improving the flow balance of the cross-section of the reaction chamber. In addition, there is no inlet and exhaust guide system for exhaust air preheating catalytic oxidizer with relatively complete structure and performance.

Contents of the invention

The purpose of the present invention is to make up for the deficiencies of the intake and exhaust diversion system of the existing coal mine exhaust air preheating catalytic oxidation device, and to provide an electronically controlled and adjustable intake and exhaust diversion system for the preheating catalytic oxidation device with double reaction chambers to ensure the reaction The air intake volume and temperature of the chamber are evenly distributed, which improves the reliability of the device operation and the oxidation rate of the exhaust gas.

The purpose of the present invention is achieved by the following technical solutions:

An electronically controlled adjustable intake and exhaust diversion system for a preheating catalytic oxidation device with double reaction chambers, including an intake main pipe, an intake branch pipe, an intake flared pipe, two intake chambers, two side-by-side reaction chambers, an exhaust The air cavity and the exhaust main pipe, wherein the outer sides of the two reaction chambers communicate with the two air intake chambers, the inner sides of the two reaction chambers communicate with the exhaust chamber, and the exhaust chamber communicates with the exhaust main pipe; each air intake chamber Both pass through an air intake flared pipe, an air intake branch pipe equipped with a regulating valve and communicate with the intake main pipe in turn. The air intake flared pipe is provided with a first deflector, and the air intake cavity is provided with a second deflector. There is a third deflector in the exhaust cavity, which is characterized in that:

Add PLC, add a set of first electric control adjustment mechanism on the outer wall of each air intake flared pipe, and add a set of second electric control adjustment mechanism on the side wall of each air intake cavity;

The expansion angle of the air inlet flared pipe is 30°~60°, the first deflector in the air inlet flared pipe adopts a straight plate shape, and each air inlet flared pipe is equipped with 4 to 6 first deflectors plate and the same number of arc-shaped guide rails, the arc-shaped guide rails are fixed horizontally on the inner wall of the intake flare pipe, and the arc-shaped guide rails are provided with a card slot matching the movable end of the first deflector plate, and the first deflector plate The movable end is slidably connected with an arc-shaped guide rail, and the other end of the first baffle is provided with a fixed shaft in the horizontal direction, and both ends of the fixed shaft pass through the side wall of the air inlet flared pipe through gaps;

There are 4 to 6 second deflectors and the same number of arc-shaped guide rails evenly distributed in each air intake chamber. The arc-shaped guide rails are vertically fixed and installed on the inner wall of the air intake chamber. The slot matching the movable end of the baffle; the movable end of the second baffle is slidably connected with an arc-shaped guide rail, and the other end of the second baffle is provided with a horizontal fixed shaft, and the second baffle is close to the fixed shaft The shape of one end is arc-shaped, and the shape of the other end is a straight plate. The transition between the two is smooth. The angle of each second baffle increases along the flow direction of the intake air. The distance between the fixed axis of the second baffle and the reaction chamber is 1/10 to 1/5 of the length of the air cavity, both ends of the fixed shaft pass through the side wall of the air cavity;

A row of third deflectors is evenly distributed on the side of the exhaust chamber close to the reaction chamber, and each row has 4 to 6 third deflectors, and each third deflector is fixedly installed on the inner wall of the exhaust chamber. The included angle of the reaction chamber is 40°～60°, the shape of the third deflector near the end of the reaction chamber is arc-shaped, and the shape of the other end is a straight plate, and the transition between the two is smooth;

The first electronic control adjustment mechanism includes multiple motors and multiple differential pressure gauges installed on the outer wall of the expansion section of the air inlet, wherein the power output end of each motor corresponds to the fixed shaft in the expansion section of the air inlet through a coupling. The ends are fixedly connected, and multiple differential pressure gauges detect the pressure difference distribution along the width direction of the reaction chamber, the side of the reaction chamber near the inlet chamber and the side near the exhaust chamber along the airflow direction;

The second electronic control adjustment mechanism includes multiple motors and multiple differential pressure gauges installed on the side wall of the air intake chamber, wherein the power output end of each motor is fixed to the end of the fixed shaft in the air intake chamber through a coupling connected, multiple differential pressure gauges detect the pressure difference distribution along the height direction of the reaction chamber, and the pressure difference distribution between the side of the reaction chamber near the inlet chamber and the side near the exhaust chamber along the airflow direction;

The input terminal of the PLC is connected to the output terminals of multiple differential pressure gauges, and the output terminal of the PLC is connected to the control terminal of each motor.

In the electronically controlled adjustable intake and exhaust diversion system of the dual-reaction chamber preheating catalytic oxidation device, diversion cones are arranged at the connection between the intake manifold and the two intake branch pipes.

Its working principle is:

The coal mine exhaust air is divided into two parts after entering the main intake pipe, and enters two side-by-side reaction chambers through the intake branch pipes on both sides of the preheating catalytic oxidation device, the intake flaring pipe and the intake chamber respectively. After the oxidation reaction, the exhaust gas is collected in the exhaust chamber and finally discharged from the device through the exhaust manifold. The differential pressure gauge collects the pressure difference between the side near the inlet chamber and the side near the exhaust chamber of the two reaction chambers, and outputs the collected data to the PLC. According to the data of the differential pressure gauge, the PLC controls the output torque of the motor, drives the fixed shaft and the deflector to rotate through the coupling, and adjusts the angle of the first deflector in the air inlet flared pipe and the second deflector in the air intake chamber. adjust. The pressure difference data output by the differential pressure gauge is divided into four groups, two of which are the pressure difference distribution of the two reaction chambers along the horizontal centerline of the flow section, and the other two are the pressure difference distribution of the two reaction chambers along the vertical centerline of the flow section . The pressure difference distribution of the two reaction chambers along the horizontal centerline of the flow section is adjusted by the first deflector in the inlet flared pipe, and the pressure difference distribution of the reaction chamber along the vertical centerline of the flow section is adjusted by the second guide plate in the air inlet cavity. flow plate to adjust. The PLC processes the four sets of pressure difference data separately. The processing method is: PLC calculates the mean square error of each set of pressure differences. If the mean square error exceeds a reasonable range, calculate the average value of the pressure difference of the set, and then calculate the pressure difference and the average value of the set. According to the deviation, determine the variation of the inclination angle of each deflector corresponding to the group of pressure differences, and then calculate the corresponding rotation angle of each deflector and the torque output by the motor, and the PLC output signal to each corresponding motor for adjustment The angle of the deflector, calculate the mean square error of the new group of pressure differences, if the mean square error is within a reasonable range, stop adjusting, if the mean square error is still beyond the reasonable range, continue to adjust according to the above method until the mean square error of each group of pressure differences Reduce to a reasonable range, and finally make the pressure difference in the vertical longitudinal direction and horizontal transverse direction of the reaction chamber reach a uniform distribution.

Compared with the prior art, the present invention has main advantages and beneficial effects:

1. The deflector system is equipped with a sufficient number of deflectors in the inlet flared pipe, the inlet chamber and the exhaust chamber, which can ensure that the horizontal and vertical distribution of the cross-section of the reaction chamber has the same air intake volume. Better balance, while avoiding flow dead angle and eddy current, so that the overall flow resistance of the device is reduced. The regulating valve of the air intake branch pipe can adjust the intake air volume of the two reaction chambers to ensure the uniform intake air volume of the two reaction chambers.

2. The angles of the air inlet flaring pipe and the deflector of the air inlet chamber are adjusted in real time according to the pressure difference signal of the differential pressure gauge. In the larger case, a better temperature balance is maintained in the cross-section of the reaction chamber.

3. The root of the deflector in the air intake chamber adopts a circular arc, which smoothly transitions to the straight plate at the end, and a certain gap is reserved between the root of the deflector and the reaction chamber, which avoids the flow dead angle at the root of the deflector and reduces the local flow in the reaction chamber , so that the distribution of the intake air at the inlet of the reaction chamber is balanced and continuous, making the catalytic oxidation process more stable and reliable.

Description of drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is a left view of the structure of the embodiment shown in Fig. 1 .

Fig. 3 is an A-A sectional view of the structure of the embodiment shown in Fig. 1 .

Fig. 4 is an enlarged structural schematic view of the second deflector and the arc-shaped sliding rail in the air intake cavity of the embodiment shown in Fig. 1 .

In the figure: 1. Air intake main pipe 2, air intake branch pipe 3, air intake flared pipe 4, air intake chamber 5, reaction chamber 6, exhaust chamber 7, exhaust main pipe 8, regulating valve 9, first deflector 10. Second deflector 11, third deflector 12, PLC 13, arc guide rail 14, card slot 15, fixed shaft 16, motor 17, differential pressure gauge 18, coupling 19, diversion cone

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings. In the embodiment shown in Fig. 1～4:

The outsides of the two reaction chambers 5 communicate with the two air intake chambers 4 respectively, and the inboards of the two reaction chambers 5 communicate with the exhaust chamber 6, and the exhaust chamber 6 communicates with the exhaust manifold 7; each air intake chamber 4 Pass through an air intake flaring pipe 3 and an air intake branch pipe 2 provided with a regulating valve 8 in order to communicate with the intake main pipe 1, and a diversion cone 19 is arranged at the connection between the air intake main pipe 1 and the two air intake branch pipes 2, and then A first deflector 9 is provided in the gas flare pipe 3, a second deflector 10 is provided in the air intake chamber 4, and a third deflector 11 is provided in the exhaust chamber 6;

A PLC 12 is set, a set of first electric control adjustment mechanism is set on the outer wall of each air intake flared pipe 3, and a set of second electric control adjustment mechanism is set on the side wall of each air intake cavity 4;

The expansion angle of the air intake flared pipe 3 is 50°, the first deflector 9 in the air intake flared pipe 3 adopts a straight plate shape deflector, and each air intake flared pipe 3 is provided with 4 first deflectors. The flow plate 9 and the same number of arc guide rails 13, the arc guide rails 13 are fixed horizontally on the inner wall of the air intake flared pipe 3, and the arc guide rails 13 are provided with a card slot matching the movable end of the first deflector plate 9 14. The movable end of the first deflector 9 is slidably connected with an arc-shaped guide rail 13, and the other end of the first deflector 9 is provided with a fixed shaft 15 in the horizontal direction, and both ends of the fixed shaft 15 pass through the gap. The side wall of the gas flared pipe 3;

Each air intake chamber 4 is evenly distributed with 4 second deflectors 10 and the same number of arc guide rails 13, the arc guide rails 13 are vertically fixedly installed on the inner wall of the air intake chamber 4, and the arc guide rails 13 are provided with The slot 14 matched with the movable end of the second deflector 10; the movable end of the second deflector 10 is correspondingly connected with an arc-shaped guide rail 13, and the other end of the second deflector 10 is provided with a fixed shaft in the horizontal direction 15. The shape of the end of the second deflector 10 close to the fixed shaft 15 is arc-shaped, and the shape of the other end is a straight plate. The two transition smoothly. The distance between the fixed shaft 15 of the deflector 10 and the reaction chamber 5 is 1/8 of the length of the air inlet chamber 4, and both ends of the fixed shaft 15 pass through the side wall of the air inlet chamber 4 through gaps;

One row of third deflectors 11 is evenly distributed on the side near the reaction chamber 5 in the exhaust chamber 6, and each row has four third deflectors 11, and each third deflector 11 is fixedly installed in the exhaust chamber 6. On the inner wall, the included angle with the reaction chamber 5 is 50°, the shape of the third deflector 11 near the end of the reaction chamber 5 is arc-shaped, and the shape of the other end is a straight plate, and the two smoothly transition;

The first electric control adjustment mechanism includes multiple motors 16 and a plurality of differential pressure gauges 17 installed on the outer wall of the expansion section of the air inlet, wherein the power output end of each motor 16 corresponds to the expansion section of the air inlet through a coupling 18. The ends of the inner fixed shaft 15 are fixedly connected, and a plurality of differential pressure gauges 17 detect the pressure difference distribution along the airflow direction between the reaction chamber 5 along the width direction, the side of the reaction chamber 5 close to the inlet cavity 4 and the side close to the exhaust cavity 6;

The second electronically controlled adjustment mechanism includes a plurality of motors 16 and a plurality of differential pressure gauges 17 installed on the side wall of the air intake cavity 4, wherein the power output end of each motor 16 is corresponding to the inner surface of the air intake cavity 4 through a coupling 18. The ends of the fixed shaft 15 are fixedly connected, and a plurality of differential pressure gauges 17 detect the pressure difference distribution of the reaction chamber 5 along the height direction, the side of the reaction chamber 5 close to the inlet cavity 4 and the side close to the exhaust cavity 6 along the airflow direction;

The input terminal of PLC 12 is connected to the output terminals of multiple differential pressure gauges 17 , and the output terminal of PLC 12 is connected to the control terminal of each motor 16 .

Claims (2)

1. An electronically controlled adjustable intake air diversion system for a preheating catalytic oxidation device with double reaction chambers, comprising an intake main pipe (1), an intake branch pipe (2), an intake flared pipe (3), two intake ports chamber (4), two side-by-side reaction chambers (5), exhaust chamber (6) and exhaust manifold (7), wherein the outsides of the two reaction chambers (5) communicate with the two inlet chambers (4) respectively , the inner sides of the two reaction chambers (5) are connected with the exhaust chamber (6), and the exhaust chamber (6) is connected with the exhaust main pipe (7); The mouth pipe (3), an air intake branch pipe (2) provided with a regulating valve (8) communicates with the air intake main pipe (1), and a first deflector (9) is arranged in the air intake flared pipe (3), The air intake chamber (4) is provided with a second deflector (10), and the exhaust chamber (6) is provided with a third deflector (11), characterized in that: Add PLC (12), add a set of first electric control adjustment mechanism on the outer wall of each air intake flared pipe (3), and add a set of second electric control mechanism on the side wall of each air intake cavity (4). regulator; The expansion angle of the air intake flared pipe (3) is 30°～60°, the first deflector (9) in the air intake flared pipe (3) adopts a straight plate shape deflector, and each air intake flared pipe (3) There are 4 to 6 first deflectors (9) and the same number of arc guide rails (13), and the arc guide rails (13) are horizontally and fixedly installed on the inner wall of the air intake flared pipe (3) , the curved guide rail (13) is provided with a card slot (14) matching the movable end of the first deflector (9), and the movable end of the first deflector (9) is correspondingly slid with an arc guide rail (13) Connected, the other end of the first deflector (9) is provided with a fixed shaft (15) in the horizontal direction, and the two ends of the fixed shaft (15) pass through the side wall of the air intake flared pipe (3) in a gap; 4～6 second baffles (10) and the same number of curved guide rails (13) are evenly distributed in each air intake chamber (4), and the arc guide rails (13) are vertically fixedly installed in the air intake chamber (4 ) on the inner wall, the curved guide rail (13) is provided with a card slot (14) matching the movable end of the second deflector (10); the movable end of the second deflector (10) corresponds to an arc guide rail (13) sliding connection, the other end of the second deflector (10) is provided with a fixed shaft (15) in the horizontal direction, the shape of the second deflector (10) near the end of the fixed shaft (15) is arc-shaped, and the other end The shape of the straight plate is a smooth transition between the two, and the angle of each second deflector (10) increases sequentially along the direction of intake flow, and the fixed shaft (15) of the second deflector (10) is connected to the reaction chamber (5) The distance between them is 1/10～1/5 of the length of the air intake chamber (4), and both ends of the fixed shaft (15) pass through the side wall of the air intake chamber (4) through gaps; One row of third deflectors (11) is evenly distributed on the side close to the reaction chamber (5) in the exhaust chamber (6), with 4 to 6 third deflectors (11) in each row, and each third deflector The flow plate (11) is fixedly installed on the inner wall of the exhaust chamber (6), and the included angle with the reaction chamber (5) is 40°～60°. The shape of the third flow guide plate (11) near the end of the reaction chamber (5) is Arc, the shape of the other end is a straight plate, and the transition between the two is smooth; The first electronically controlled adjustment mechanism includes multiple motors (16) and multiple differential pressure gauges (17) installed on the outer wall of the expansion section of the air inlet, wherein the power output end of each motor (16) passes through a shaft coupling (18) ) is correspondingly fixedly connected to the end of the fixed shaft (15) in the expansion section of the air inlet, and multiple differential pressure gauges (17) detect that the reaction chamber (5) is along the width direction, and the reaction chamber (5) is close to the air inlet chamber (4) The pressure difference distribution along the airflow direction between the side and the side close to the exhaust chamber (6); The second electronically controlled adjustment mechanism includes multiple motors (16) and multiple differential pressure gauges (17) installed on the side wall of the air intake cavity (4), wherein the power output end of each motor (16) is connected through a shaft coupling (18) corresponds to the fixed connection with the end of the fixed shaft (15) in the air intake chamber (4), and multiple differential pressure gauges (17) detect that the reaction chamber (5) is along the height direction, and the reaction chamber (5) is close to the air intake chamber The pressure difference distribution along the airflow direction between the (4) side and the side close to the exhaust chamber (6); The input terminal of the PLC (12) is connected to the output terminals of a plurality of differential pressure gauges (17), and the output terminal of the PLC (12) is connected to the control terminal of each motor (16). 2. According to claim 1, the electronically controlled adjustable air intake diversion system of the double reaction chamber preheating catalytic oxidation device is characterized in that: the connection between the intake main pipe (1) and the two intake branch pipes (2) is arranged A diversion cone (19) is arranged.