CN213690254U - Flue gas denitration ammonia injection automatic control system - Google Patents
Flue gas denitration ammonia injection automatic control system Download PDFInfo
- Publication number
- CN213690254U CN213690254U CN202022766427.6U CN202022766427U CN213690254U CN 213690254 U CN213690254 U CN 213690254U CN 202022766427 U CN202022766427 U CN 202022766427U CN 213690254 U CN213690254 U CN 213690254U
- Authority
- CN
- China
- Prior art keywords
- ammonia
- flue gas
- flue
- pid controller
- ammonia injection
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Sampling And Sample Adjustment (AREA)
Abstract
The utility model relates to the technical field of automatic control, in particular to an ammonia spraying automatic control system for flue gas denitration, which comprises a PID controller, a single-side draught fan, a DCS system, an ammonia spraying adjusting unit, a flue gas flow detecting unit, a flue gas analyzer, an ammonia spraying flowmeter and an ammonia escape analyzer; the signal output end of the PID controller is connected with the signal input end of the ammonia spraying adjusting unit, the signal input end of the PID controller is connected with the output end of the DCS, the PID controller is used for receiving signals of the DCS, theoretical ammonia spraying amount corresponding to nitrogen oxide flow is obtained through a theoretical calculation formula, and the ammonia spraying amount is controlled through the ammonia spraying adjusting unit; the DCS system obtains more accurate data and can feed back more accurate signals to the PID controller, and therefore the content of nitrogen oxides at the outlet of the SCR is accurately controlled to be close to a target value.
Description
Technical Field
The patent of the utility model relates to an automatic control technical field particularly, relates to an ammonia automatic control system is spouted in flue gas denitration.
Background
The logic of the denitration ammonia injection automatic control method adopted in the prior art is to obtain the flow of nitric oxide in flue gas by adopting the product of the flow of flue gas and the content of nitric oxide at an SCR inlet, obtain the theoretical ammonia injection amount corresponding to the flow of nitric oxide by a theoretical calculation formula, and control an ammonia injection regulating valve to control the ammonia injection amount by taking the theoretical ammonia injection amount as feedforward. The Chinese patent with the application number of 2016101457066 discloses an automatic ammonia injection control system for desulfurization and denitrification, wherein the outlet of an ammonia tank is connected with the inlet of an evaporator generator through a pipeline, the pipeline is sequentially connected with a pressure transmitter, an inlet flow meter, an inlet instantaneous valve and an electric valve, the outlet of the steam generator is connected with the inlet of a mixing tank through the pipeline, the outlet of the mixing tank is connected with the outlet of the electric valve, the instantaneous valve and the tail end of an outlet flow meter output pipeline through an output pipeline in sequence to form an automatic ammonia injection control pipeline, and a spraying mechanism is installed on the automatic ammonia injection control pipeline; in order to accurately control the content of the nitrogen oxides at the SCR outlet to be close to a target value, a PID closed-loop control strategy is added, and the theoretical ammonia injection amount is corrected, so that the nitrogen oxides at the SCR outlet are controlled to be close to the target value.
The control strategy for controlling the ammonia injection amount has the defects of pure delay, large inertia, multiple external disturbance factors and the like:
1. the original PID regulation has no feedforward and cannot be adjusted quickly;
2. the flow measurement point is single-point pitot tube measurement, and the measurement is not representative and has insufficient precision;
3. a flue gas analyzer (NOX concentration) is used for single-point sampling, and the sampling mode cannot truly reflect the uniformity of ammonia spraying of the whole denitration system;
4. the straight pipe section of the ammonia injection flowmeter is short, and disturbances such as a shut-off valve, a thermometer sleeve, an ammonia injection regulating valve bypass pipeline and the like exist before and after the installation position of the flowmeter, so that the problems of large measurement error, unsatisfied specification and the like exist;
5. the ammonia escape analyzer is an in-situ laser, the measuring distance of a light source is only about two to three meters, and the installation position is arranged on one of four corners of a flue and is not representative.
This causes a large deviation between the calculation result of the theoretical ammonia injection amount and the actually required ammonia injection amount, and the measurement of the ammonia gas flow is sometimes not very accurate, so that the ammonia injection amount calculated by the theory is not ideal in the actual application; therefore, the automatic control system for the ammonia injection in the flue gas denitration is provided.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide an ammonia automatic control system is spouted in flue gas denitration aims at solving the problem among the prior art.
The utility model discloses a realize like this:
an automatic control system for ammonia spraying in flue gas denitration comprises a PID controller, a single-side induced draft fan, a DCS system, an ammonia spraying adjusting unit, a flue gas flow detecting unit, a flue gas analyzer, an ammonia spraying flowmeter and an ammonia escape analyzer; wherein the content of the first and second substances,
the signal output end of the PID controller is connected with the signal input end of the ammonia spraying adjusting unit, the signal input end of the PID controller is connected with the output end of the DCS, the PID controller is used for receiving signals of the DCS, theoretical ammonia spraying amount corresponding to nitrogen oxide flow is obtained through a theoretical calculation formula, and the ammonia spraying amount is controlled through the ammonia spraying adjusting unit;
the DCS is connected with the signal output ends of the flue gas flow detection unit, the flue gas analyzer, the ammonia injection flow meter and the ammonia escape analyzer, and is used for receiving signals detected by the flue gas flow detection unit, the flue gas analyzer, the ammonia injection flow meter and the ammonia escape analyzer, performing a series of calculations and inputting calculation results into the PID controller;
the single-side induced draft fan is arranged on one side of the flue and used for inducing air into the flue, a circuit of the single-side induced draft fan is connected with a signal output end of the PID controller, and current of the single-side induced draft fan is used as a feedforward signal of the PID controller;
the ammonia spraying adjusting unit is arranged on the ammonia spraying pipeline and is a plurality of ammonia spraying adjusting valves and used for controlling the ammonia spraying amount of the ammonia spraying pipeline according to signals fed back by the PID controller;
the flue gas flow detection unit is arranged in the flue and used for detecting the flow of flue gas;
the sampling sensor of the flue gas analyzer is arranged in the flue and used for detecting the concentration of nitrogen oxides;
the ammonia injection flowmeter is arranged in the ammonia injection pipeline and used for detecting the ammonia injection amount;
the ammonia escape analyzer is arranged in the flue and used for measuring ammonia escape.
Through the technical scheme, the disturbance change caused by the unit load can be quickly responded, so that the response speed of the PID controller is improved, and the accurate control of the automatic ammonia injection regulation is finally realized.
As a flue gas denitration spouts further explanation of ammonia automatic control system, preferably, flue gas flow detecting element adopts matrix flow measuring device.
Through foretell technical scheme, can improve flue gas flow measurement's precision greatly, provide more accurate data for the DCS system.
As a flue gas denitration spouts further explanation of ammonia automatic control system, preferably, flue gas analysis appearance includes a plurality of sampling sensors, and is a plurality of the sampling sensor equidistance is installed on the net grid, the net grid is installed in the flue for flue gas to in the flue carries out the sampling of multiple spot.
Through foretell technical scheme, adopt the grid multipoint mode of sampling, can guarantee the accuracy to the flue gas sample, can truly reflect the homogeneity that whole deNOx systems spouts the ammonia, provide more accurate data for the DCS system.
As a flue gas denitration spouts further explanation of ammonia automatic control system, preferably, spout ammonia flowmeter and adopt for mass flow meter.
Through foretell technical scheme, improve and spout the precision of ammonia flow measurement, provide more accurate data for the DCS system.
As a flue gas denitration spouts further explanation of ammonia automatic control system, preferably, ammonia escape analysis appearance includes light source and light source receiver, the light source adopts with diode laser, the light source with the central point that the flue both sides were installed respectively to the light source receiver puts.
According to the technical scheme, the analyzer with the diode laser light source with the longer measuring distance is directly installed at the center positions of the two sides of the flue, and the measuring light source penetrates through the whole flue, so that the section of the whole flue is measured, and the accuracy of ammonia escape measurement is greatly improved.
Compared with the prior art, the utility model provides an automatic control system for flue gas denitration and ammonia injection,
1. the current of the single-side induced draft fan is used as a feedforward signal, so that the disturbance change caused by the load of the unit can be quickly responded, the response speed of the PID controller is improved, and the accurate control of the automatic ammonia spraying regulation is finally realized;
2. by adopting the matrix type flow measuring device, the accuracy of flue gas flow measurement can be greatly improved, and more accurate data is provided for a DCS (distributed control system);
3. by adopting a grid multi-point sampling mode, the accuracy of sampling the flue gas can be ensured, the uniformity of ammonia spraying of the whole denitration system can be truly reflected, and more accurate data is provided for a DCS (distributed control system);
4. the mass flowmeter is adopted, the accuracy of ammonia injection flow measurement is improved, and more accurate data are provided for a DCS (distributed control system);
5. an analyzer of a diode laser light source with a longer measuring distance is directly arranged at the center positions of two sides of the flue, and the measuring light source penetrates through the whole flue, so that the section of the whole flue is measured, and the accuracy of ammonia escape measurement is greatly improved;
the DCS system obtains more accurate data and can feed back more accurate signals to the PID controller, and therefore the content of nitrogen oxides at the outlet of the SCR is accurately controlled to be close to a target value.
Drawings
FIG. 1 is a block diagram of an automatic control system for ammonia injection in flue gas denitration.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail with reference to fig. 1 and the following embodiments. It should be understood that the detailed description and specific examples, while indicating the invention, are given by way of illustration only.
The implementation of the present invention will be described in detail below with reference to preferred embodiments.
As shown in fig. 1, in a specific embodiment, an automatic control system for ammonia injection in flue gas denitration comprises a PID controller 100, a single-side induced draft fan 200, a DCS system 300, an ammonia injection adjusting unit 400, a flue gas flow rate detecting unit 500, a flue gas analyzer 600, an ammonia injection flow meter 700, and an ammonia escape analyzer 800; wherein the content of the first and second substances,
the signal output end of the PID controller 100 is connected with the signal input end of the ammonia spraying adjusting unit 400, the signal input end of the PID controller 100 is connected with the output end of the DCS 300, the PID controller 100 is used for receiving the signal of the DCS 300, obtaining the theoretical ammonia spraying amount corresponding to the flow of the nitrogen oxides through a theoretical calculation formula, and controlling the ammonia spraying amount through the ammonia spraying adjusting unit 400;
the DCS 300 is connected with the signal output ends of the flue gas flow detection unit 500, the flue gas analyzer 600, the ammonia injection flow meter 700 and the ammonia escape analyzer 800, and the DCS 300 is used for receiving signals detected by the flue gas flow detection unit 500, the flue gas analyzer 600, the ammonia injection flow meter 700 and the ammonia escape analyzer 800, performing a series of calculations and inputting the calculation results into the PID controller 100;
the unilateral induced draft fan 200 is arranged on one side of the flue, the unilateral induced draft fan 200 is used for inducing air into the flue, the circuit of the unilateral induced draft fan 200 is connected with the signal output end of the PID controller 100, and the current of the unilateral induced draft fan 200 is used as a feedforward signal of the PID controller 100;
the ammonia injection regulating unit 400 is installed on the ammonia injection pipeline, and the ammonia injection regulating unit 400 is a plurality of ammonia injection regulating valves and is used for controlling the ammonia injection amount of the ammonia injection pipeline according to signals fed back by the PID controller 100;
the flue gas flow detection unit 500 is arranged in the flue and used for detecting the flow of flue gas;
the sampling sensor of the flue gas analyzer 600 is arranged in the flue and used for detecting the concentration of nitrogen oxides;
the ammonia injection flowmeter 700 is arranged in the ammonia injection pipeline and used for detecting the ammonia injection amount;
the ammonia escape analyzer 800 is disposed in the flue for measuring ammonia escape.
During operation, the flue gas flow is measured by the flue gas flow detection unit 500 and then transmitted to the DCS 300 for flow calculation, the NOx concentration is sampled by the sampling sensor, the flue gas analyzer 600 analyzes and then transmits the analyzed and transmitted to the DCS 300, the ammonia spraying amount measured by the ammonia spraying flowmeter 700 is transmitted to the DCS 300, finally the ammonia escape analyzer 800 transmits the measured ammonia escape amount to the DCS 300, the data enters the DCS 300 and then enters the PID controller 100 capable of automatically adjusting and used for controlling ammonia spraying after a series of calculations, the current of the single-side induced draft fan 200 serves as a feedforward signal, disturbance change caused by unit load can be quickly responded, the response speed of adjustment of the PID controller 100 is improved, and accurate control of automatic adjustment of ammonia spraying is finally achieved.
As an embodiment of the utility model, flue gas flow detection unit 500 adopts matrix flow measuring device, and matrix flow measuring device is more accurate than single-point pitot tube measuring result, improves flue gas flow measuring's precision greatly, provides more accurate data for DCS system 300.
As an embodiment of the utility model, flue gas analyzer 600 includes a plurality of sampling sensors, and is a plurality of sampling sensor equidistance is installed on the net grid, the net grid is installed in the flue for flue gas to in the flue carries out the sampling of multiple spot, adopts net multiple-point type sampling mode, can guarantee the accuracy to the flue gas sample, can truly reflect the homogeneity that whole deNOx systems spouts the ammonia, provides more accurate data for DCS system 300.
As an embodiment of the utility model, spout ammonia flowmeter 700 and adopt for mass flow meter, improve and spout the precision of ammonia flow measurement, provide more accurate data for DCS system 300.
As an embodiment of the utility model, ammonia escape analysis appearance 800 includes light source and light source receiver, the light source adopts with diode laser, the light source with light source receiver installs respectively in the central point of flue both sides puts, adopts the farther diode laser light source's of measuring distance analysis appearance, and direct mount puts in flue both sides central point, and the measuring light source crosses whole flue to measure whole flue cross-section, improve ammonia escape measuring accuracy greatly.
In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like, indicate the orientation or positional relationship indicated based on the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.
In the present application, unless expressly stated or limited otherwise, the first feature may be directly on or directly under the second feature or indirectly via intermediate members. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.
Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations may be made to the above embodiments by those of ordinary skill in the art without departing from the scope of the present invention.
Claims (5)
1. An automatic control system for ammonia injection in flue gas denitration is characterized by comprising a PID controller, a single-side draught fan, a DCS system, an ammonia injection adjusting unit, a flue gas flow detecting unit, a flue gas analyzer, an ammonia injection flowmeter and an ammonia escape analyzer; wherein the content of the first and second substances,
the signal output end of the PID controller is connected with the signal input end of the ammonia spraying adjusting unit, the signal input end of the PID controller is connected with the output end of the DCS, the PID controller is used for receiving signals of the DCS, theoretical ammonia spraying amount corresponding to nitrogen oxide flow is obtained through a theoretical calculation formula, and the ammonia spraying amount is controlled through the ammonia spraying adjusting unit;
the DCS is connected with the signal output ends of the flue gas flow detection unit, the flue gas analyzer, the ammonia injection flow meter and the ammonia escape analyzer, and is used for receiving signals detected by the flue gas flow detection unit, the flue gas analyzer, the ammonia injection flow meter and the ammonia escape analyzer, performing a series of calculations and inputting calculation results into the PID controller;
the single-side induced draft fan is arranged on one side of the flue and used for inducing air into the flue, a circuit of the single-side induced draft fan is connected with a signal output end of the PID controller, and current of the single-side induced draft fan is used as a feedforward signal of the PID controller;
the ammonia spraying adjusting unit is arranged on the ammonia spraying pipeline and is a plurality of ammonia spraying adjusting valves and used for controlling the ammonia spraying amount of the ammonia spraying pipeline according to signals fed back by the PID controller;
the flue gas flow detection unit is arranged in the flue and used for detecting the flow of flue gas;
the sampling sensor of the flue gas analyzer is arranged in the flue and used for detecting the concentration of nitrogen oxides;
the ammonia injection flowmeter is arranged in the ammonia injection pipeline and used for detecting the ammonia injection amount;
the ammonia escape analyzer is arranged in the flue and used for measuring ammonia escape.
2. The automatic control system for flue gas denitration ammonia injection of claim 1, wherein the flue gas flow detection unit adopts a matrix flow measurement device.
3. The automatic control system for flue gas denitration ammonia injection of claim 1, wherein the flue gas analyzer comprises a plurality of sampling sensors, the plurality of sampling sensors are equidistantly mounted on a grid, and the grid is mounted in the flue and used for sampling the flue gas in the flue at multiple points.
4. The automatic control system for ammonia injection in flue gas denitration of claim 1, wherein the ammonia injection flow meter is a mass flow meter.
5. The automatic control system of ammonia injection for denitration of flue gas of claim 1, wherein the ammonia escape analyzer comprises a light source and a light source receiver, the light source adopts diode laser, and the light source receiver are respectively installed at the central positions of both sides of the flue.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022766427.6U CN213690254U (en) | 2020-11-25 | 2020-11-25 | Flue gas denitration ammonia injection automatic control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022766427.6U CN213690254U (en) | 2020-11-25 | 2020-11-25 | Flue gas denitration ammonia injection automatic control system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213690254U true CN213690254U (en) | 2021-07-13 |
Family
ID=76735857
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022766427.6U Active CN213690254U (en) | 2020-11-25 | 2020-11-25 | Flue gas denitration ammonia injection automatic control system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213690254U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113750793A (en) * | 2020-06-17 | 2021-12-07 | 绍兴旗滨玻璃有限公司 | Ammonia injection control method and device for flue gas denitration, terminal equipment and storage medium |
-
2020
- 2020-11-25 CN CN202022766427.6U patent/CN213690254U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113750793A (en) * | 2020-06-17 | 2021-12-07 | 绍兴旗滨玻璃有限公司 | Ammonia injection control method and device for flue gas denitration, terminal equipment and storage medium |
| CN113750793B (en) * | 2020-06-17 | 2023-10-13 | 绍兴旗滨玻璃有限公司 | Ammonia spraying control method and device for flue gas denitration, terminal equipment and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107544288B (en) | Denitration optimization control method and system | |
| US9557744B2 (en) | System for and method of monitoring flow through mass flow controllers in real time | |
| EP3117137B1 (en) | System for monitoring flow through mass flow controllers in real time | |
| EP1864104B1 (en) | Wide range continuous diluter | |
| CN109813400B (en) | Boiler main steam flowmeter online checking and testing system based on internet of things technology | |
| JP2003287477A (en) | Exhaust emission analysis system and method for correcting measurement of exhaust emission | |
| CN213690254U (en) | Flue gas denitration ammonia injection automatic control system | |
| KR101760259B1 (en) | Extractive continuous ammonia monitoring system | |
| CN104028172A (en) | Control of ammonia feeding for ammoxidation reactor | |
| CN108106679A (en) | A kind of measuring method and system of power station coal pulverizer inlet air quantity | |
| CN115752600A (en) | Intelligent monitoring system and method for flue gas flow of fixed pollution source | |
| CN113970937A (en) | SCR denitration accurate ammonia injection control method | |
| CN113578007A (en) | Coal-fired flue gas SCR denitration regulation and control system and method based on partitioned ammonia injection | |
| CN211785102U (en) | Flue gas denitrating ammonia escape measurement and analysis device based on multi-point sampling | |
| CN106526092A (en) | Automatic calibration system for ammonia escape | |
| CN209476006U (en) | A kind of NOx subregion patrols survey dynamic spray ammonia balance control system | |
| CN206348319U (en) | The escaping of ammonia automatic calibration system | |
| CN115824327A (en) | Method and system for detecting air flow, storage medium and computer equipment | |
| CN116838458A (en) | SCR closed-loop control device and control method | |
| CN215449154U (en) | Ammonia spraying measurement and control system based on synchronous measurement data of whole cross section and same interface of flue | |
| CN214308921U (en) | Smoke and air volume measuring device capable of preventing air flow disturbance | |
| CN1117977C (en) | Coal powder density measuring method and measuring controller | |
| CN215449164U (en) | Ammonia spraying balance detection device for denitration reactor | |
| CN2490167Y (en) | Dew-point detecting device of continuous annealing furnace | |
| CN207096084U (en) | A kind of device of on-line determination the escaping of ammonia in situ |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |