CN118604382A - A device and method for monitoring the flue gas velocity of a fixed pollution source - Google Patents

Abstract

The present invention discloses a device and method for monitoring the flow velocity of flue gas from a fixed pollution source. The partition rectifier of the device comprises an inner annular partition, a middle annular partition and an outer annular partition arranged coaxially from the inside to the outside. The partition rectifier is provided with multiple areas and is equipped with ultrasonic sensors. The flue is partitioned and small holes are appropriately arranged on each partition to stabilize the fluid pressure difference between the partitions, thereby rectifying the flue gas. The partition rectifier rotates periodically, and the ultrasonic sensors arranged in pairs on the partition partitions perform two measurements to form an X-shaped cross measurement line, which not only reduces the number of sensors but also further reduces the influence of swirl on the velocity measurement accuracy, thereby realizing the use of a small number of ultrasonic sensors to complete the flow velocity monitoring of multiple partitions, which not only improves the flow velocity monitoring accuracy but also reduces the monitoring cost. It has the characteristics of simple structure and convenient operation, and has broad application prospects.

Description

A device and method for monitoring the flue gas velocity of a fixed pollution source

Technical Field

The present invention relates to the field of devices and methods for monitoring the flow rate of flue gas from a fixed pollution source, and in particular to a device and method for monitoring the flow rate of flue gas from a fixed pollution source.

Background Art

The large-scale use of fossil energy is the most direct cause of the global increase in carbon dioxide. Among them, industry is the main area of fossil energy use, and most of these emission sources are fixed sources. The use of fossil energy (such as coal combustion in thermal power plants and oil refining) is often accompanied by the production of sulfides, nitrides, mercury, etc. that have serious impacts on the quality of the atmospheric environment. Early atmospheric pollution monitoring focused more on the pollution monitoring of these sulfides and nitrides. However, with the requirements of carbon verification and carbon footprint evaluation, there is a demand for monitoring the amount of carbon dioxide emitted from flue gas during the use of fixed-source fossil energy. Slightly different from the previous pollution control needs of sulfides, nitrides, etc., the monitoring of carbon dioxide emissions pays more attention to the monitoring of emissions, that is, not only the same as the monitoring of pollutants such as sulfides and nitrides, but also the accuracy of flue gas flux monitoring. Higher requirements are placed on the monitoring accuracy. However, since the flue size is usually large and there are many factors affecting the flue gas flow, flue gas turbulence seriously affects the flow rate monitoring of such large-section channels. In addition, the Pitot tube method traditionally used in the early monitoring of sulfide, nitrogen and other pollution monitors the flue gas flow rate. Experimental studies have shown that in a flue with a diameter of 1.2 meters, the flue gas flux monitoring results obtained with the highest accuracy by the Pitot tube method also cause large errors in the calculation of carbon dioxide emissions. The direct penetration method for ultrasonic flow rate monitoring requires more than 8 pairs of probes, and a special arrangement method that matches the flow field swirl can barely meet the accuracy requirements of carbon dioxide verification and trading, which seriously affects the promotion of carbon verification and trading based on carbon dioxide monitoring technology.

Summary of the invention

In view of the above-mentioned technical deficiencies, the purpose of the present invention is to provide a fixed pollution source flue gas flow rate monitoring device and method, which can partition and rectify large-size pipelines, reduce interference between streamlines, balance the fluid pressures in different partitions, reduce turbulence in the pipeline, and simultaneously perform periodic measurements of the fluid partitions in the pipeline, thereby reducing the stringent requirements for direct ultrasonic probe installation and improving the monitoring accuracy of flue flow rate.

In order to solve the above technical problems, the present invention adopts the following technical solutions:

The present invention provides a device and method for monitoring the flue gas velocity of a fixed pollution source, comprising a partition rectifier installed at the upper end of a chimney, wherein the partition rectifier comprises an inner annular partition, a middle annular partition and an outer annular partition arranged coaxially from the inside to the outside, and a plurality of circumferential partitions uniformly distributed in an annular array are fixed on the outer wall of the inner annular partition, and the circumferential partition passes through the middle annular partition and is fixedly connected to the inner wall of the outer annular partition, thereby fixing the inner annular partition, the middle annular partition and the outer annular partition together;

The partition rectifier is connected to the upper end of the chimney through two fixed brackets arranged above and below it, and both ends of the two fixed brackets are fixed on the chimney. Two rectifier brackets are symmetrically arranged at the upper and lower ends of the partition rectifier. The rectifier bracket is n-type and its two ends are fixed on the rectifier bracket. A rotating motor is fixed in the middle of the lower fixed bracket. The output end of the rotating motor is connected to the middle of the rectifier bracket on the same side through the lower support shaft to drive the partition rectifier to rotate; the middle part of the upper fixed bracket is rotatably connected to the upper support shaft and a collector ring is arranged at the connection point, and the other end of the upper support shaft is fixed to the middle of the rectifier bracket on the same side;

The circumferential partition, the inner annular partition and the middle annular partition are all provided with honeycomb holes. A plurality of ultrasonic sensors for detecting air flow velocity are arranged in the partition rectifier. The ultrasonic sensors are connected to an external ultrasonic monitor through a collector ring.

Preferably, the honeycomb holes on the circumferential partition plate, the inner annular partition plate and the middle annular partition plate have a diameter of 3-5 mm and a spacing of 20-40 mm.

Preferably, the outer annular partition is parallel to the inner wall of the chimney of the installation section, and the distance between the two is controlled to be 5±0.5 mm.

Preferably, there are eight circumferential partitions, and the eight circumferential partitions divide the partitioned rectifier into 17 areas.

Preferably, the inner wall of the outer annular partition is provided with a first outer ultrasonic sensor and a second outer ultrasonic sensor in two axially symmetrical regions, respectively, and a connecting line of the two outer ultrasonic sensors passes through the central axis of the outer annular partition;

A first intermediate ultrasonic sensor and a second intermediate ultrasonic sensor are respectively provided on the outer wall of the intermediate annular partition in the above two areas, and a connecting line of the two intermediate ultrasonic sensors passes through the central axis of the outer annular partition;

The first outer ultrasonic sensor is located higher than the first middle ultrasonic sensor in the same area and the line connecting the two forms an angle of 45-60 degrees with the vertical;

The second outer ultrasonic sensor is located lower than the second middle ultrasonic sensor in the same area, and the line connecting the second outer ultrasonic sensor and the second middle ultrasonic sensor forms an angle of 45-60 degrees with the vertical.

Preferably, the inner wall of the middle annular partition is provided with a third middle ultrasonic sensor and a fourth middle ultrasonic sensor in two axially symmetrical regions, respectively, and the connecting line of the two middle ultrasonic sensors passes through the central axis of the outer annular partition;

The outer wall of the inner annular partition is provided with a first inner ultrasonic sensor and a second inner ultrasonic sensor in the above two areas, respectively, and the connecting line of the two inner ultrasonic sensors passes through the central axis of the outer annular partition;

The position of the third middle ultrasonic sensor is higher than the first inner ultrasonic sensor in the same area and the line connecting the two forms an angle of 45-60 degrees with the vertical;

The fourth middle ultrasonic sensor is located lower than the second inner ultrasonic sensor in the same area and the line connecting the second inner ultrasonic sensor and the vertical direction forms an angle of 45-60 degrees.

Preferably, a first internal ultrasonic sensor and a second internal ultrasonic sensor are axially symmetrically arranged on the inner wall of the inner annular partition, and a line connecting the two internal ultrasonic sensors forms an angle of 45-60 degrees with the vertical direction.

The present invention also provides a method for using a fixed pollution source flue gas velocity monitoring device, comprising:

During the measurement process, the partition rectifier rotates periodically at 45°/time, pauses for more than 1 minute after each rotation, and measures the flow velocity in the area;

Through the above operation, the flue is divided into 17 symmetrical areas, and one cycle of measurement is completed every 8 rotations; and in each cycle, the first outer ultrasonic sensor, the second outer ultrasonic sensor, the first middle ultrasonic sensor, and the second middle ultrasonic sensor all measure the flow rate once in the outermost 8 partitions, and form an X-shaped cross measurement line in each partition;

For each partition, the average value of the flow rates measured by the first outer ultrasonic sensor, the second outer ultrasonic sensor, the first middle ultrasonic sensor, and the second middle ultrasonic sensor is taken;

Similarly, the third middle ultrasonic sensor, the fourth middle ultrasonic sensor, the first inner ultrasonic sensor, and the second inner ultrasonic sensor also form an X-shaped cross-measurement line in the middle 8 areas, and the flow velocity is averaged;

The first internal ultrasonic sensor and the second internal ultrasonic sensor measure 8 times and take an average value;

The flux is calculated by the flow velocity in each area, and the total flux is obtained by summing up; the flow velocity correction coefficient is obtained according to the actual flow velocity, and the flue gas flow is monitored in real time according to the measured value and the correction coefficient.

The beneficial effects of the present invention are as follows: the present invention uses partitions to partition the flue, and uses appropriate small holes in the partitions to increase the pressure balance between the flow channels, reduce the fluid disturbance between the flow channels for rectification. The flow velocity is measured by partitioning through periodic rotation, the flow field distribution is refined, and the monitoring capability of the non-uniform characteristics of the flow field distribution is improved. In addition, an X-shaped cross measurement is formed between two sensors in the same partition in one cycle, which further increases the monitoring accuracy of the flow field partition flow velocity, improves the stability and accuracy of the flow velocity monitoring of large-sized flues, is easy to operate, and has a wide range of applications.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

FIG1 is a schematic diagram of the position of the operating platform at the upper end of the chimney provided by an embodiment of the present invention;

FIG2 is a schematic diagram of the installation position of a fixed pollution source flue gas velocity monitoring device provided by an embodiment of the present invention;

FIG3 is a schematic diagram of the appearance of a partitioned rectifier provided in an embodiment of the present invention;

FIG4 is a schematic diagram of the internal structure of a partitioned rectifier provided in an embodiment of the present invention;

FIG5 is a schematic diagram of the installation positions of various ultrasonic sensors provided in an embodiment of the present invention;

Fig. 6 is a cross-sectional view taken along line C-C in Fig. 5 .

Description of reference numerals:

1. Partition rectifier; 2. Operating platform; 3. Fixed bracket; 4. Rotating motor; 5. Support shaft; 51. Upper support shaft; 6. Rectifier bracket; 7. Collector ring; 8. Circumferential partition; 9. Inner annular partition; 10. Middle annular partition; 11. Outer annular partition. 12A. First outer ultrasonic sensor; 12B. First middle ultrasonic sensor; 13A. Second outer ultrasonic sensor; 13B. Second middle ultrasonic sensor; 14A. Fourth middle ultrasonic sensor; 14B. Second inner ultrasonic sensor; 15A. Third middle ultrasonic sensor; 15B. First inner ultrasonic sensor; 16A. First inner ultrasonic sensor; 16B. Second inner ultrasonic sensor.

DETAILED DESCRIPTION

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

As shown in FIGS. 1 to 6 , a fixed pollution source flue gas velocity monitoring device installation position includes an operating platform 2 of a partition rectifier 1 installed at the upper end of a chimney, wherein the partition rectifier 1 includes an inner annular partition 9, an intermediate annular partition 10, and an outer annular partition 11 coaxially arranged from the inside to the outside, and a plurality of circumferential partitions 8 uniformly distributed in an annular array are fixed on the outer wall of the inner annular partition 9, and the circumferential partition 8 penetrates the intermediate annular partition 10 and is fixedly connected to the inner wall of the outer annular partition 11, thereby fixing the inner annular partition 9, the intermediate annular partition 10, and the outer annular partition 11 together;

The partition rectifier 1 is connected to the upper end of the chimney through two fixed brackets 3 arranged above and below it, and both ends of the two fixed brackets 3 are fixed on the chimney. Two rectifier brackets 6 are symmetrically arranged at the upper and lower ends of the partition rectifier 1. The rectifier bracket 6 is n-shaped and its two ends are fixed on the rectifier bracket 6. A rotating motor 4 is fixed in the middle of the lower fixed bracket 3. The output end of the rotating motor 4 is connected to the middle of the rectifier bracket 6 on the same side through the lower support shaft 5, thereby driving the partition rectifier 1 to rotate; the middle part of the upper fixed bracket 3 is rotatably connected to the upper support shaft 51 and a collector ring 7 is arranged at the connection point, and the other end of the upper support shaft is fixed to the middle of the rectifier bracket 6 on the same side;

The circumferential partition plate 8 , the inner annular partition plate 9 , and the middle annular partition plate 10 are all provided with honeycomb holes. A plurality of ultrasonic sensors for detecting air flow velocity are arranged in the partition rectifier 1 . The ultrasonic sensors are connected to an external ultrasonic monitor through a collector ring 7 .

The honeycomb holes on the circumferential partition plate 8, the inner annular partition plate 9 and the middle annular partition plate 10 have a diameter of 3-5 mm and a spacing of 20-40 mm.

The outer annular partition plate 11 is parallel to the inner wall of the chimney of the installation section, and the distance between the two is controlled to be 5±0.5mm.

There are eight circumferential partitions 8 , and the eight circumferential partitions 8 divide the partition rectifier 1 into 17 areas.

The inner wall of the outer annular partition 11 is provided with a first outer ultrasonic sensor 12A and a second outer ultrasonic sensor 13A in two axially symmetrical regions, respectively, and the connecting line of the two outer ultrasonic sensors passes through the central axis of the outer annular partition 11;

The outer wall of the middle annular partition 10 is provided with a first middle ultrasonic sensor 12B and a second middle ultrasonic sensor 13B in the above two areas, respectively, and the connecting line of the two middle ultrasonic sensors passes through the central axis of the outer annular partition 11;

The first outer ultrasonic sensor 12A is located higher than the first middle ultrasonic sensor 12B in the same area, and the line connecting the two forms an angle of 45-60 degrees with the vertical;

The second outer ultrasonic sensor 13A is located lower than the second middle ultrasonic sensor 13B in the same area, and the line connecting the two forms an angle of 45-60 degrees with the vertical.

The inner wall of the middle annular partition 10 is provided with a third middle ultrasonic sensor 15A and a fourth middle ultrasonic sensor 14A in two axially symmetrical regions, respectively, and the connecting line of the two middle ultrasonic sensors passes through the central axis of the outer annular partition 11;

The outer wall of the inner annular partition 9 is provided with a first inner ultrasonic sensor 15B and a second inner ultrasonic sensor 14B in the above two areas, respectively, and the connecting line of the two inner ultrasonic sensors passes through the central axis of the outer annular partition 11;

The position of the third middle ultrasonic sensor 15A is higher than the first inner ultrasonic sensor 15B in the same area, and the line connecting the two forms an angle of 45-60 degrees with the vertical;

The fourth middle ultrasonic sensor 14A is located lower than the second inner ultrasonic sensor 14B in the same area and the line connecting the second inner ultrasonic sensor 14B forms an angle of 45-60 degrees with the vertical.

A first internal ultrasonic sensor 16A and a second internal ultrasonic sensor 16B are axially symmetrically arranged on the inner wall of the inner annular partition 9, and a line connecting the two internal ultrasonic sensors forms an angle of 45-60 degrees with the vertical direction.

The present invention also provides a method for using a fixed pollution source flue gas velocity monitoring device, comprising:

During the measurement process, the partition rectifier 1 rotates periodically at 45°/time, pauses for more than 1 minute after each rotation, and measures the flow velocity in the area;

Through the above operation, the flue is divided into 17 symmetrical areas, and one cycle of measurement is completed every 8 rotations; and in each cycle, the first outer ultrasonic sensor 12A, the second outer ultrasonic sensor 13A, the first middle ultrasonic sensor 12B, and the second middle ultrasonic sensor 13B perform a flow velocity measurement in the outermost 8 partitions, and form an X-shaped cross measurement line in each partition;

For each partition, the average value of the flow rates measured by the first outer ultrasonic sensor 12A, the second outer ultrasonic sensor 13A, the first middle ultrasonic sensor 12B, and the second middle ultrasonic sensor 13B is taken;

Similarly, the third middle ultrasonic sensor 15A, the fourth middle ultrasonic sensor 14A, the first inner ultrasonic sensor 15B, and the second inner ultrasonic sensor 14B also form an X-shaped cross-measurement line in the middle eight areas, and the flow velocity is averaged;

The first internal ultrasonic sensor 16A and the second internal ultrasonic sensor 16B measure 8 times and take an average value;

The flux is calculated by the flow velocity in each area, and the total flux is obtained by summing up; the flow velocity correction coefficient is obtained according to the actual flow velocity, and the flue gas flow is monitored in real time according to the measured value and the correction coefficient.

The device rectifies the flue gas by partitioning the flue and properly setting small holes on each partition to stabilize the fluid pressure difference between the partitions. The partition rectifier rotates periodically, and the ultrasonic sensors set in pairs on the partition partitions make two measurements to form an X-shaped cross measurement line, which not only reduces the number of sensors but also further reduces the impact of swirl on the speed measurement accuracy, thereby realizing the use of a small number of ultrasonic sensors to complete multiple partition flow rate monitoring, which not only improves the flow rate monitoring accuracy but also reduces the monitoring cost. It has the characteristics of simple structure and convenient operation, and has broad application prospects.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (8)

1. The utility model provides a fixed pollution source flue gas velocity of flow monitoring devices, its characterized in that includes partition rectifier (1) of installing in the chimney upper end, partition rectifier (1) is including inside annular baffle (9), middle annular baffle (10) and outside annular baffle (11) that inside coaxial line arranged from inside to outside, be fixed with a plurality of circumference baffle (8) that are annular array equipartition on the outer wall of inside annular baffle (9), circumference baffle (8) run through middle annular baffle (10) and fixed connection are in outside annular baffle (11) inner wall thereby with inside annular baffle (9), middle annular baffle (10), outside annular baffle (11) fixed connection together;

The partition rectifier (1) is connected to the upper end of the chimney through two fixing brackets (3) arranged above and below the partition rectifier (1), two ends of the two fixing brackets (3) are fixed on the chimney, two rectifier brackets (6) are symmetrically arranged at the upper end and the lower end of the partition rectifier (1), the rectifier brackets (6) are n-shaped, two ends of the rectifier brackets are fixed on the rectifier brackets (6), a rotating motor (4) is fixed in the middle of the fixing bracket (3) below, and the output end of the rotating motor (4) is connected with the middle of the rectifier brackets (6) at the same side through a lower supporting shaft (5) so as to drive the partition rectifier (1) to rotate; the middle part of the upper fixed support (3) is rotationally connected with an upper support shaft (51) and a collecting ring (7) is arranged at a connecting point, and the other end of the upper support shaft is fixed at the middle part of the rectifier support (6) at the same side;

The device is characterized in that honeycomb holes are formed in the circumferential partition plate (8), the inner annular partition plate (9) and the middle annular partition plate (10), a plurality of ultrasonic sensors used for detecting air flow velocity are arranged in the partition rectifier (1), and the ultrasonic sensors are connected with an external ultrasonic monitor through a collecting ring (7).

2. A fixed pollution source flue gas flow rate monitoring device according to claim 1, wherein the pore diameter of the honeycomb holes on the circumferential partition plate (8), the inner annular partition plate (9) and the middle annular partition plate (10) is 3-5mm, and the interval is 20-40mm.

3. A stationary source flue gas flow rate monitoring device according to claim 1, characterized in that the outer annular partition (11) is parallel to the inner wall of the chimney of the installation section, the distance between them being controlled at 5±0.5mm.

4. A stationary source flue gas flow rate monitoring device according to claim 2, characterised in that eight circumferential partitions (8) are provided, the eight circumferential partitions (8) dividing the segmented rectifier (1) into 17 areas.

5. A fixed pollution source flue gas flow rate monitoring device according to claim 4, wherein the inner wall of the outer annular partition (11) is respectively provided with a first outer ultrasonic sensor (12A) and a second outer ultrasonic sensor (13A) in two axisymmetric areas, and the connection line of the two outer ultrasonic sensors passes through the central axis of the outer annular partition (11);

the outer wall of the middle annular partition plate (10) is respectively provided with a first middle ultrasonic sensor (12B) and a second middle ultrasonic sensor (13B) in the two areas, and the connecting line of the two middle ultrasonic sensors passes through the central axis of the outer annular partition plate (11);

the first outer ultrasonic sensor (12A) is higher than the first middle ultrasonic sensor (12B) in the region, and an included angle between the connecting line of the first outer ultrasonic sensor and the first middle ultrasonic sensor and the vertical line is 45-60 degrees;

The second outside ultrasonic sensor (13A) is lower than the second middle ultrasonic sensor (13B) in the region, and an included angle between the connecting line of the second outside ultrasonic sensor and the second middle ultrasonic sensor is 45-60 degrees from the vertical direction.

6. A fixed pollution source flue gas flow rate monitoring device according to claim 5, wherein the inner wall of the middle annular partition plate (10) is respectively provided with a third middle ultrasonic sensor (15A) and a fourth middle ultrasonic sensor (14A) in two axisymmetric areas, and the connecting line of the two middle ultrasonic sensors passes through the central axis of the outer annular partition plate (11);

the outer wall of the inner annular partition plate (9) is respectively provided with a first inner ultrasonic sensor (15B) and a second inner ultrasonic sensor (14B) in the two areas, and the connecting line of the two inner ultrasonic sensors passes through the central axis of the outer annular partition plate (11);

the position of the third middle ultrasonic sensor (15A) is higher than that of the first inner ultrasonic sensor (15B) in the region, and an included angle of 45-60 degrees is formed between the connecting line of the third middle ultrasonic sensor and the first inner ultrasonic sensor and the vertical line;

the position of the fourth middle ultrasonic sensor (14A) is lower than that of the second inner ultrasonic sensor (14B) in the region, and an included angle of 45-60 degrees is formed between the connecting line of the fourth middle ultrasonic sensor and the second inner ultrasonic sensor and the vertical line.

7. The device and method for monitoring the flow rate of the flue gas with the fixed pollution source according to claim 6, wherein the first internal ultrasonic sensor (16A) and the second internal ultrasonic sensor (16B) are axisymmetrically arranged on the inner wall of the inner annular partition plate (9), and an included angle of 45-60 degrees is formed between a connecting line of the two internal ultrasonic sensors and the vertical direction.

8. A method of using the stationary source flue gas flow rate monitoring device according to claim 7,

In the measuring process, the partition rectifier (1) periodically rotates at 45 degrees/times, stops for more than 1min after each rotation, and measures the flow velocity of the area;

Through the operation, the flue is divided into 17 symmetrical areas, and one period measurement is completed every 8 times of rotation; the first outer ultrasonic sensor (12A), the second outer ultrasonic sensor (13A), the first intermediate ultrasonic sensor (12B) and the second intermediate ultrasonic sensor (13B) perform primary flow velocity measurement in 8 outermost subareas in each period, and an X-shaped cross-test line is formed in each subarea;

taking an average value of flow rates measured by a first outer ultrasonic sensor (12A), a second outer ultrasonic sensor (13A), a first middle ultrasonic sensor (12B) and a second middle ultrasonic sensor (13B) from each partition;

Similarly, the third middle ultrasonic sensor (15A), the fourth middle ultrasonic sensor (14A), the first inner ultrasonic sensor (15B) and the second inner ultrasonic sensor (14B) form X-shaped cross test lines in 8 middle areas, and the flow velocity is averaged;

the first internal ultrasonic sensor (16A) and the second internal ultrasonic sensor (16B) are measured 8 times, and an average value is obtained;

Calculating flux by each zone flow velocity and obtaining total flux by summing; and obtaining a flow velocity correction coefficient according to the real flow velocity, and monitoring the flue gas flow in real time according to the measured value and the correction coefficient.