CN114166990A - Based on NOxDenitrification ammonia injection uniformity detection method based on concentration time domain characteristic analysis - Google Patents
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- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 122
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 61
- 238000002347 injection Methods 0.000 title claims abstract description 47
- 239000007924 injection Substances 0.000 title claims abstract description 47
- 238000004458 analytical method Methods 0.000 title claims abstract description 24
- 238000001514 detection method Methods 0.000 title claims abstract description 17
- 238000006477 desulfuration reaction Methods 0.000 claims abstract description 64
- 230000023556 desulfurization Effects 0.000 claims abstract description 63
- 238000011156 evaluation Methods 0.000 claims abstract description 14
- 238000000034 method Methods 0.000 claims abstract description 13
- 239000003546 flue gas Substances 0.000 claims description 26
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims description 24
- 238000005507 spraying Methods 0.000 claims description 14
- 230000008859 change Effects 0.000 claims description 8
- 239000007789 gas Substances 0.000 claims description 4
- 230000014759 maintenance of location Effects 0.000 claims description 4
- 238000012544 monitoring process Methods 0.000 claims description 4
- 238000011835 investigation Methods 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 238000000738 capillary electrophoresis-mass spectrometry Methods 0.000 claims 7
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- 238000005457 optimization Methods 0.000 abstract description 2
- 238000005259 measurement Methods 0.000 abstract 1
- 230000004048 modification Effects 0.000 description 4
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- 238000010531 catalytic reduction reaction Methods 0.000 description 2
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- 238000005299 abrasion Methods 0.000 description 1
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000009849 deactivation Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000000428 dust Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000004134 energy conservation Methods 0.000 description 1
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- 231100001143 noxa Toxicity 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 231100000572 poisoning Toxicity 0.000 description 1
- 230000000607 poisoning effect Effects 0.000 description 1
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- 239000000700 radioactive tracer Substances 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
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- 239000000243 solution Substances 0.000 description 1
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Abstract
The invention discloses a method based on NOxThe denitration ammonia injection uniformity detection method based on concentration time domain feature analysis comprises the following steps: calculating the mean deviation of the load time distribution of the generator set, dividing the load distribution, taking the load section with the largest proportion as a high-frequency load section, and carrying out NO when the load distribution of the generator set is stablexAnalyzing the concentration time domain and calculating NO at the outlet of the denitration systemxAverage concentration and desulfurization system outlet NOxAverage relative deviation of concentration, and calculating NO at outlet of denitration system at adjacent peak time in evaluation periodxMean peak concentration and desulfurization system outlet NOxAnd judging the uniformity of denitration ammonia injection by the average relative deviation of the peak concentration. The online evaluation method of the invention passes through NO at the outlet of the desulfurization system and the denitration systemxCorrelation analysis and peak comparison of concentration distribution, and online evaluation of denitration outlet NOxAnd the measurement points are representative, the ammonia injection uniformity of the denitration system is effectively reflected, and a technical guide is provided for the subsequent ammonia injection optimization adjustment.
Description
Technical Field
The invention relates to the technical field of denitration by a selective catalytic reduction method of a coal-fired power generating set, in particular to a denitration method based on NOxA denitration ammonia injection uniformity detection method based on concentration time domain characteristic analysis.
Background
With the comprehensive popularization of ultralow emission of coal-fired power generating sets, the fine operation requirement of environmental protection facilities is stricter and stricter. At present, the ammonia spraying uniformity judgment of a coal-fired power generating set SCR (selective Catalytic reduction) denitration system is mainly carried out by adopting a direct measurement method: for a traditional denitration system which is not provided with an outlet matrix type monitoring device, the denitration system can only be developed in an off-line detection mode, a detection result has time lag and limitation, subsequent ammonia injection adjustment cannot be guided in time, and the operation efficiency of the denitration system cannot be improved. In order to accurately evaluate the ammonia injection operation performance of the SCR denitration system of the coal-fired power generator set on line and avoid the result hysteresis generated by off-line test, an on-line evaluation method for the ammonia injection uniformity of the denitration system with general applicability needs to be fully constructed, the evaluation efficiency of the environment-friendly facility operation state of the coal-fired power generator set is effectively improved, and the national energy conservation and emission reduction bureau is served.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide the NO-based denitration system which can realize online real-time evaluation of denitration ammonia injection uniformity and service efficient and stable operation of the denitration systemxDenitrification of concentration time domain feature analysisAnd (4) evaluation method of ammonia spraying uniformity.
In order to solve the technical problems, the invention adopts the following technical scheme.
Based on NOxThe denitration ammonia injection uniformity detection method based on concentration time domain feature analysis comprises the following steps:
calculating the mean deviation of the load time distribution of the generator set;
dividing load distribution, wherein the load section with the largest proportion is used as a high-frequency load section and a target load section for ammonia injection adjustment;
when the mean deviation of the load time distribution of the generator set reaches a set interval and is in a high-frequency load section, NO is carried outxAnalyzing the time domain characteristics of the concentration, constructing the change relation of the residence time random group load of the flue gas from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system, and calculating the NO at the outlet of the denitration systemxAverage concentration and desulfurization system outlet NOxThe average relative deviation of the concentration is recorded as a first average relative deviation, and NO at the outlet of the denitration system in the adjacent peak time in the evaluation period is calculatedxMean peak concentration and desulfurization system outlet NOxThe average relative deviation of the peak concentration is recorded as a second average relative deviation;
and judging the uniformity of the denitration ammonia injection according to the first average relative deviation and the second average relative deviation so as to perform ammonia injection control according to the judgment result of the uniformity.
Preferably, the mean deviation formula for calculating the load time distribution of the generator set is as follows:
wherein, CV isLIs the mean deviation of the load time distribution of a single generator set, unit percent and sigmaLThe standard deviation of the load time distribution of a single generator set is dimensionless, T is an investigation time period and is in units of s and LiIs the running load of the unit in the ith period in the T period, unit MW,
the unit MW is the average value of the unit load in the T period, and the unit MW is the unit s/time of the unit load numerical value sampling frequency.
Preferably, the denitration ammonia injection uniformity detection method based on the time domain characteristic analysis of the NOx concentration divides the load distribution according to a three-stage system: the high load section is 75 percent<L is less than or equal to 100 percent, and the high-load section ratio is set as PLHUnit% and medium load section is 50%<L is less than or equal to 75 percent, and the proportion of the middle load section is set as PLMThe unit percent, the low-load section is less than or equal to 50 percent, and the percentage of the low-load section is set as PLLThe load section with the largest unit% is determined as a high-frequency load section;
comparing P at monthly and annual time scalesLH、PLM、PLLIs characterized by the distribution ofLH、PLM、PLLThe ammonia injection adjustment is carried out in the high-frequency load section under the annual time scale when the distribution characteristics of the month and the year are consistent, and the ammonia injection adjustment is carried out in the high-frequency load section under the monthly time scale when the distribution characteristics of the month and the year are different.
Preferably, the denitration ammonia injection uniformity detection method based on time domain characteristic analysis of NOx concentration is implemented when mean deviation of load time distribution of the generator set<At 30%, NO is carried outxAnd (5) analyzing the time domain characteristics of the concentration.
Preferably, the change relation formula of the random group load of the residence time of the flue gas from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system is constructed as follows:
wherein tau (L) is the retention time from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system, and the unit is s, Qgas(L) is the flue gas flow rate in unit m when the unit load is L3L is unit load in MW, VS-FThe unit m from the outlet of the denitration system to the outlet flue volume of the desulfurization system3。
Preferably, the denitration ammonia injection uniformity detection method based on the time domain characteristic analysis of the NOx concentration calculates NO at the outlet of the denitration systemxAverage concentration and desulfurization system outlet NOxThe course of the relative deviation in concentration is as follows:
the outlet of the denitration system is provided with an A side outlet and a B side outlet, and NO of the A side outlet and NO of the B side outlet of the denitration system are calculatedxAverage concentration:
wherein, CNOx,SCRFor the outlet NO of the denitration systemxAverage concentration in mg/m3，CNOx,AFor the outlet NO of the A side of the denitration systemxConcentration in mg/m3，CNOx,BFor the outlet NO of the B side of the denitration systemxConcentration in mg/m3，QA、QBThe unit m is the flue gas flow of the A side and the B side of the denitration system3/h；
Calculate denitration system A, B side outlet NOxAverage concentration and desulfurization system outlet NOxAverage relative deviation of concentration:
wherein RDNOx, averageSide outlet NO for denitration system A, BxAverage concentration and desulfurization system outlet NOxAverage relative deviation of concentration, in%, RDNOx(t) denitration system A, B side outlet NO at time txAverage concentration and desulfurization system outlet NOxReal-time relative deviation of concentration, in%, CNOx,SCR(t) NO at the outlet on the side of the denitration system A, B at time txAverage concentration in mg/m3，CNOx,FGD(t) desulfurization system outlet NO at time txAverage concentration in mg/m3T is a data acquisition period, and the unit s and F are data acquisition frequency and the unit s/time.
Preferably, the denitration ammonia injection uniformity detection method based on the time domain characteristic analysis of the NOx concentration calculates NO at the outlet of the denitration system in the adjacent peak-out time in the evaluation periodxMean peak concentration and desulfurization system outlet NOxThe average relative deviation of the peak concentrations proceeds as follows:
wherein RDNOx，peak(T) is the outlet NO of the denitration system in the T periodxMean peak concentration and desulfurization system outlet NOxAverage relative deviation of peak concentration, in%, CNOx,SCR,peak(k) Is the kth NO at the outlet of the denitration system in the T periodxAverage peak concentration in mg/m3，CNOx,FGD,peak(k) Is the kth NO at the outlet of the desulfurization system in the T periodxPeak concentration in mg/m3And n is the number of peak values in the T period and is unit.
Preferably, when the two following criteria are simultaneously satisfied, the method for detecting the denitration ammonia injection uniformity based on the time-domain characteristic analysis of the NOx concentration is as follows:
criterion 1: RDNOx, average>20％，
Criterion 2: RDNOx，peak(T)>15％，
It is determined that the side outlet NO of the nox removal system A, BxConcentration CEMS monitoring value and A, B side outlet flue section NOxThe actual concentration has larger deviation and can not effectively reflect the real NO at the A, B side of the denitration systemxThe emission concentration level indicates that the uniformity of the side ammonia injection of the denitration system A, B is poor, and ammonia injection control is needed.
Compared with the prior art, the invention has the advantages that:
the invention is based on the NO at the outlet of the desulfurization/denitrification systemxAnd (4) performing correlation analysis, and evaluating the ammonia injection uniformity of the denitration system on line to provide a technical basis for subsequent ammonia injection adjustment. When the denitration system is in operation, due to ash deposition blockage, catalyst abrasion/poisoning/deactivation, large deviation of A/B side flow and A/B side NOxThe concentration deviation is large, and the like, which causes NO monitored by a denitration outlet CEMS measuring pointxThe concentration can not effectively reflect the real NO at the outlet of the denitration systemxThe concentration level. Therefore, the invention adopts the method based on the outlet NO of the desulfurization/denitrification systemXCorrelation analysis and peak value comparison can effectively reflect the ammonia spraying uniformity of the denitration system.
The invention is based on the NO at the outlet of the desulfurization/denitrification systemXThe online evaluation method for the ammonia spraying uniformity of the denitration system based on correlation analysis is used for evaluating the ammonia spraying uniformity of the SCR denitration system, and can identify the non-uniform abnormality of ammonia spraying in time and guarantee the efficient and stable operation of the tail end equipment of the unit. The invention correlatively analyzes NO in the flue gas with the same source at the desulfurization/denitrification outletxConcentration of NOx to outlet NOxRepresentative real-time assessment of concentration based on desulfurization/denitrification Outlet NOxThe periodic peak value comparison of the concentration can realize the denitration outlet NOxThe distribution uniformity (namely ammonia spraying uniformity) is detected and evaluated on line, and technical guidance is provided for subsequent ammonia spraying adjustment.
Drawings
FIG. 1 shows NO-based samples according to example 1 of the present inventionxA flow diagram of a denitration ammonia injection uniformity detection method based on concentration time domain characteristic analysis.
FIG. 2 shows the outlet NO of the denitration system and the outlet NO of the desulfurization system in example 1 of the present inventionxTypical profile of concentration over time.
Detailed Description
The invention is further described below with reference to the drawings and specific preferred embodiments of the description, without thereby limiting the scope of protection of the invention. The materials and equipment used in the following examples are commercially available.
Example 1:
an NO-based composition of the inventionxA denitration ammonia injection uniformity detection method based on concentration time domain characteristic analysis is used for carrying out NO at an outlet of a desulfurization system when a single coal-fired power generating set normally operatesxAnd denitration system outlet NOxThe correlation analysis of (1) and the on-line evaluation of the ammonia spraying uniformity of the denitration system, as shown in fig. 1, comprises the following steps:
step S1, firstly, the load time distribution characteristics of the generator set are developed. Mean deviation CV for examining load time distribution of single unit in calculation period (T, day/month/year)L：
Wherein, CV isLThe mean deviation of the load time distribution of a single generator set is unit percent; sigmaLThe standard deviation of the load time distribution of a single generator set is dimensionless; t is the investigation time period, unit s; l isiThe unit MW is the operation load of the unit in the ith time period in the T period;
the unit MW is the average value of the unit load in the T period; f is the unit s/time of unit load numerical value sampling frequency.
The purpose of analyzing the load time distribution characteristics of the unit is toAnalysing the variation of load for subsequent NOxThe accuracy of the analysis result can be ensured only on the premise that the load is relatively stable in the concentration time domain characteristic analysis.
And step S2, carrying out high-frequency load section analysis. Load distribution is divided according to a three-stage system: high load section (75%<L is less than or equal to 100%) of PLH(%), medium load section (50%)<L is less than or equal to 75%) is contained in PLMThe percentage ratio P of the low-load section (less than or equal to 50 percent)LL(%). The load section having the largest proportion can be identified as a high-frequency load section, that is, a target load section for performing ammonia injection regulation.
Respectively comparing the proportion distribution characteristics of each load section under the time scale of the month and the year, namely PLH、PLM、PLLIn the order of magnitude. When the distribution characteristics of the month and the year tend to be consistent (for example, both are PLH>PLM>PLL) The ammonia injection adjustment is recommended to be carried out in a high-frequency load section under the annual time scale; the distribution characteristics of the month and year are different (for example, the month is mainly high load, PLH>PLM>PLLYear is mainly medium load, PLM>PLH>PLL) Then the ammonia injection adjustment is recommended to be carried out in the high frequency load band on the monthly time scale.
Step S3, when the load distribution of the unit is stable, i.e. the mean deviation CVL<At 30%, NO is evolvedxAnd (5) analyzing the time domain characteristics of the concentration. NO in flue gasxThe key measuring points of the concentration are mainly a denitration system outlet CEMS (continuous flue gas emission monitoring system) and a desulfurization system outlet (total exhaust) CEMS, so that on the premise of ensuring the accuracy of the measuring points of the CEMS, NO at the denitration outlet is analyzedxConcentration and desulfurization outlet NOxThe consistency matching (steps S4-S5) determines the ammonia spraying uniformity of the denitration system on line, and provides a technical basis for adjusting whether ammonia spraying needs to be carried out or not.
After flowing out from the outlet of the denitration system, the coal-fired flue gas sequentially passes through the dedusting system and the desulfurization system, and finally enters the main discharge port of the chimney through the outlet of the desulfurization system to be discharged into the atmospheric environment. Because the dust removal system and the desulfurization system are opposite to NOxThe gas has no obvious absorption or removal effect,theoretically, NO in the flue gas after the flue gas at the outlet of the denitration system passes through the dedusting and desulfurization systemxThe concentration should remain constant. Meanwhile, the flue gas needs a certain retention time after passing through the dedusting and desulfurization system and reaching the chimney main exhaust port, so that the denitration system CEMS and the desulfurization system CEMS have a certain difference in the same time.
And analyzing the change relation tau (L) of the residence time tau(s) of the flue gas from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system by adopting a flue gas tracer method or other methods, wherein the change relation tau (L) is the load L (MW) of a random group, and providing basic reference data for subsequent analysis. A typical calculation is as follows:
wherein tau (L) is the retention time from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system, and is the unit s; qgas(L) is the flue gas flow rate in unit m when the unit load is L3H; l is unit load, unit MW; vS-FThe unit m from the outlet of the denitration system to the outlet flue volume of the desulfurization system3。
At a certain moment t, the flue gas starts from the outlet of the denitration system and reaches the outlet of the desulfurization system for tau (L) s seconds, and NO NO exists from the outlet of the denitration system to the outlet of the desulfurization systemxPurification of plants, therefore it can be assumed that NOxThe concentration has no significant change; meanwhile, when the flue gas flows from the denitration system to the desulfuration outlet, NO in the flue gasxHas been thoroughly mixed, so that the NO outlet of the desulfurization system isxThe concentration can reflect NO in the smokexTrue concentration level, by comparing the high frequency load section (identified in step S2) at time t, the outlet NO of the denitration systemxAverage concentration CNOx,SCRAnd t + T (L) time NO at the outlet of the desulfurization systemxConcentration CNOx,FGD(t + τ (L)) (step S4), in combination with NOxMean peak concentration and desulfurization system outlet NOxThe analysis of the relative deviation of the peak concentration (step S5) can effectively identify the NO at the outlet of the denitration systemxUniformity of concentration distribution.
The relationship between load and flue gas residence time for a typical 300MW unit is shown in Table 1:
TABLE 1 relationship between typical unit load and flue gas residence time (300 MW unit is taken as an example)
| Load factor of unit (%) | 50％ | 75％ | 100％ |
| Residence time of flue gas(s) | 62 | 47 | 30 |
Step S4, when the unit is in the high-frequency load section, the denitration system A, B side outlet NO is startedxAverage concentration and desulfurization system outlet NOxAnd analyzing the relative deviation of the concentration.
The existing denitration system outlet is usually provided with an A side outlet and a B side outlet, and NO of the A side outlet and NO of the B side outlet of the denitration system are calculatedxAverage concentration:
wherein, CNOx,SCRFor the outlet NO of the denitration systemxAverage concentration in mg/m3；CNOx,AFor the outlet NO of the A side of the denitration systemxConcentration in mg/m3；CNOx,BFor the outlet NO of the B side of the denitration systemxConcentration in mg/m3；QA、QBThe unit m is the flue gas flow of the A side and the B side of the denitration system3/h。
Calculate denitration system A, B side outlet NOxAverage concentration and desulfurization system outlet NOxAverage relative deviation of concentration:
wherein RDNOx, averageSide outlet NO for denitration system A, BxAverage concentration and desulfurization system outlet NOxAverage relative deviation in concentration, in%; RDNOx(t) denitration system A, B side outlet NO at time txAverage concentration and desulfurization system outlet NOxReal-time relative deviation of concentration, in%; cNOx,SCR(t) NO at the outlet on the side of the denitration system A, B at time txAverage concentration in mg/m3；CNOx,FGD(t) desulfurization system outlet NO at time txAverage concentration in mg/m3(ii) a T is a data acquisition period and a unit of s; f is data acquisition frequency and unit s/time.
Step S5, when the unit is in a high-frequency load section, synchronously starting an outlet NO of the denitration systemxMean peak concentration and desulfurization system outlet NOxAnalysis of the relative deviation of the peak concentration.
Comparing NO at the outlet of the denitration system in adjacent peak time within a period of evaluation period TxMean peak concentration and desulfurization system outlet NOxThe distribution of the average relative deviation of the peak concentration, as shown in fig. 2, determines whether the optimum adjustment of the ammonia injection of the denitration system needs to be performed.
Wherein RDNOx，peak(T) is the outlet NO of the denitration system in the T periodxMean peak concentration and desulfurization system outlet NOxAverage relative deviation of peak concentration, in%; cNOx,SCR,peak(k) Is the kth NO at the outlet of the denitration system in the T periodxAverage peak concentration in mg/m3；CNOx,FGD,peak(k) Is the kth NO at the outlet of the desulfurization system in the T periodxPeak concentration in mg/m3(ii) a n is the number of peak values in T period.
Step S6, detecting ammonia spraying uniformity of the denitration system:
criterion 1: RDNOx, average>20％
Criterion 2: RDNOx，peak(T)>15％
When the 2 criteria are met, the side outlet NO of the denitration system A, B is provedxConcentration CEMS monitoring value and A, B side outlet flue section NOxThe actual concentration has larger deviation and can not effectively reflect the real NO at the A, B side of the denitration systemxThe emission concentration level indicates that the uniformity of the side ammonia injection of the denitration system A, B is not good, and the total discharge port flue gas NO is easily causedxExcessive emission is not beneficial to the environment-friendly and efficient operation of the generator set, so the generator set needs to carry out ammonia injection optimization and adjustment.
The foregoing is merely a preferred embodiment of the invention and is not intended to limit the invention in any manner. Although the present invention has been described with reference to the preferred embodiments, it is not intended to be limited thereto. Those skilled in the art can make many possible variations and modifications to the disclosed embodiments, or equivalent modifications, without departing from the spirit and scope of the invention, using the methods and techniques disclosed above. Therefore, any simple modification, equivalent replacement, equivalent change and modification made to the above embodiments according to the technical essence of the present invention are still within the scope of the protection of the technical solution of the present invention.
Claims (8)
1. Based on NOxDenitrification of concentration time domain feature analysisThe ammonia spraying uniformity detection method is characterized by comprising the following steps:
calculating the mean deviation of the load time distribution of the generator set;
dividing load distribution, wherein the load section with the largest proportion is used as a high-frequency load section and a target load section for ammonia injection adjustment;
when the mean deviation of the load time distribution of the generator set reaches a set interval and is in a high-frequency load section, NO is carried outxAnalyzing the time domain characteristics of the concentration, constructing the change relation of the residence time random group load of the flue gas from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system, and calculating the NO at the outlet of the denitration systemxAverage concentration and desulfurization system outlet NOxThe average relative deviation of the concentration is recorded as a first average relative deviation, and NO at the outlet of the denitration system in the adjacent peak time in the evaluation period is calculatedxMean peak concentration and desulfurization system outlet NOxThe average relative deviation of the peak concentration is recorded as a second average relative deviation;
and judging the uniformity of the denitration ammonia injection according to the first average relative deviation and the second average relative deviation so as to perform ammonia injection control according to the judgment result of the uniformity.
2. NO-based according to claim 1xThe denitration ammonia injection uniformity detection method based on concentration time domain characteristic analysis is characterized in that a mean deviation formula for calculating load time distribution of a generator set is as follows:
wherein, CV isLIs the mean deviation of the load time distribution of a single generator set, unit percent and sigmaLThe standard deviation of the load time distribution of a single generator set is dimensionless, T is an investigation time period and is in units of s and LiIs the running load of the unit in the ith period in the T period, unit MW,
the unit MW is the average value of the unit load in the T period, and the unit MW is the unit s/time of the unit load numerical value sampling frequency.
3. NO-based according to claim 1xThe denitration ammonia injection uniformity detection method based on concentration time domain feature analysis is characterized in that load distribution is divided according to a three-section system: the high load section is 75 percent<L is less than or equal to 100 percent, and the high-load section ratio is set as PLHUnit% and medium load section is 50%<L is less than or equal to 75 percent, and the proportion of the middle load section is set as PLMThe unit percent, the low-load section is less than or equal to 50 percent, and the percentage of the low-load section is set as PLLThe load section with the largest unit% is determined as a high-frequency load section;
comparing P at monthly and annual time scalesLH、PLM、PLLIs characterized by the distribution ofLH、PLM、PLLThe ammonia injection adjustment is carried out in the high-frequency load section under the annual time scale when the distribution characteristics of the month and the year are consistent, and the ammonia injection adjustment is carried out in the high-frequency load section under the monthly time scale when the distribution characteristics of the month and the year are different.
4. NO-based according to claim 1xThe method for detecting the denitration ammonia injection uniformity of concentration time domain characteristic analysis is characterized in that the mean deviation of the load time distribution of a generator set<At 30%, NO is carried outxAnd (5) analyzing the time domain characteristics of the concentration.
5. NO-based according to any of claims 1 to 4xDenitration ammonia spraying uniformity of concentration time domain characteristic analysisThe method is characterized in that a change relation formula of the residence time random group load of the flue gas from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system is constructed as follows:
wherein tau (L) is the retention time from the outlet CEMS of the denitration system to the outlet CEMS of the desulfurization system, and the unit is s, Qgas(L) is the flue gas flow rate in unit m when the unit load is L3L is unit load in MW, VS-FThe unit m from the outlet of the denitration system to the outlet flue volume of the desulfurization system3。
6. NO-based according to claim 5xThe method for detecting the denitration ammonia injection uniformity through concentration time domain feature analysis is characterized by calculating NO at an outlet of a denitration systemxAverage concentration and desulfurization system outlet NOxThe course of the relative deviation in concentration is as follows:
the outlet of the denitration system is provided with an A side outlet and a B side outlet, and NO of the A side outlet and NO of the B side outlet of the denitration system are calculatedxAverage concentration:
wherein, CNOx,SCRFor the outlet NO of the denitration systemxAverage concentration in mg/m3，CNOx,AFor the outlet NO of the A side of the denitration systemxConcentration in mg/m3，CNOx,BFor the outlet NO of the B side of the denitration systemxConcentration in mg/m3，QA、QBThe unit m is the flue gas flow of the A side and the B side of the denitration system3/h；
Calculate denitration system A, B side outlet NOxAverage concentration and desulfurization system outlet NOxAverage relative deviation of concentration:
wherein RDNOx, averageSide outlet NO for denitration system A, BxAverage concentration and desulfurization system outlet NOxAverage relative deviation of concentration, in%, RDNOx(t) denitration system A, B side outlet NO at time txAverage concentration and desulfurization system outlet NOxReal-time relative deviation of concentration, in%, CNOx,SCR(t) NO at the outlet on the side of the denitration system A, B at time txAverage concentration in mg/m3，CNOx,FGD(t) desulfurization system outlet NO at time txAverage concentration in mg/m3T is a data acquisition period, and the unit s and F are data acquisition frequency and the unit s/time.
7. NO-based according to claim 6xThe method for detecting the denitration ammonia injection uniformity through concentration time domain characteristic analysis is characterized in that NO at an outlet of a denitration system in adjacent peak-out time in an evaluation period is calculatedxMean peak concentration and desulfurization system outlet NOxThe average relative deviation of the peak concentrations proceeds as follows:
wherein RDNOx，peak(T) is the outlet NO of the denitration system in the T periodxMean peak concentration and desulfurization system outlet NOxAverage relative deviation of peak concentration, in%, CNOx,SCR,peak(k) Is the kth NO at the outlet of the denitration system in the T periodxAverage peak concentration in mg/m3，CNOx,FGD,peak(k) Is the kth NO at the outlet of the desulfurization system in the T periodxPeak concentration in mg/m3N isThe number of peaks in the T period is unit.
8. NO-based according to claim 7xThe denitration ammonia injection uniformity detection method based on concentration time domain characteristic analysis is characterized by simultaneously meeting the following two criteria:
criterion 1: RDNOx, average>20％，
Criterion 2: RDNOx，peak(T)>15％，
It is determined that the side outlet NO of the nox removal system A, BxConcentration CEMS monitoring value and A, B side outlet flue section NOxThe actual concentration has larger deviation and can not effectively reflect the real NO at the A, B side of the denitration systemxThe emission concentration level indicates that the uniformity of the side ammonia injection of the denitration system A, B is poor, and ammonia injection control is needed.
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Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08318132A (en) * | 1995-05-29 | 1996-12-03 | Nisshin Steel Co Ltd | Method for denitrating waste gas and denitrator |
| WO2001055565A2 (en) * | 2000-01-26 | 2001-08-02 | Volkswagen Aktiengesellschaft | METHOD AND DEVICE FOR DETECTING A NOx CONCENTRATION OF AN EXHAUST GAS STREAM PERTAINING TO A COMBUSTION ENGINE |
| JP2002162393A (en) * | 2000-11-28 | 2002-06-07 | Mitsubishi Heavy Ind Ltd | Method and device for simultaneously analyzing nox and nh3 |
| US20110320132A1 (en) * | 2010-06-24 | 2011-12-29 | GM Global Technology Operations LLC | METHOD FOR THE DETERMINATION OF A NOx CONCENTRATION VALUE UPSTREAM OF A SCR CATALYST IN A DIESEL ENGINE |
| CN103592407A (en) * | 2013-11-07 | 2014-02-19 | 华北电力大学 | On-line power plant SCR (Selective Catalytic Reduction) denitration system catalyst activity monitoring method |
| DE102013112567A1 (en) * | 2012-11-15 | 2014-05-15 | Ngk Spark Plug Co., Ltd. | NOx detection device and NOx sensor system |
| JP2014102098A (en) * | 2012-11-16 | 2014-06-05 | Mitsubishi Heavy Ind Ltd | System and method for diagnosing catalyst in exhaust gas denitration device |
| JP2015190356A (en) * | 2014-03-28 | 2015-11-02 | 日立造船株式会社 | Method and device for measuring nox removal efficiency for engine |
| CN105547388A (en) * | 2015-12-07 | 2016-05-04 | 华北电力大学（保定） | Flue gas flow rate on-line calibration method used for desulphurization denitration control |
| CN107252630A (en) * | 2017-05-31 | 2017-10-17 | 国家电网公司 | A kind of method for optimizing the distribution of SCR denitration system ammonia nitrogen mol ratio |
| US20190226382A1 (en) * | 2016-10-07 | 2019-07-25 | Cpt Group Gmbh | On-Board Diagnostics for an Exhaust Gas Catalytic Converter and Detection of Aging |
| CN111359438A (en) * | 2020-04-09 | 2020-07-03 | 国电环境保护研究院有限公司 | Ammonia spraying optimization control method and control system for SCR flue gas denitration device |
| CN211955407U (en) * | 2020-04-09 | 2020-11-17 | 国电南京电力试验研究有限公司 | System for accurately monitoring nitrogen oxide and ammonia concentration in coal-fired flue gas in subareas |
| CN112504994A (en) * | 2020-12-18 | 2021-03-16 | 润电能源科学技术有限公司 | Denitration flue gas concentration field on-line measuring system and denitration ammonia injection system |
| CN112697977A (en) * | 2020-12-24 | 2021-04-23 | 重庆大唐国际石柱发电有限责任公司 | Thermal power station boiler flue gas NOx index prediction method |
| CN112705046A (en) * | 2020-12-16 | 2021-04-27 | 苏州西热节能环保技术有限公司 | Denitration ammonia injection fine adjustment method and device |
-
2021
- 2021-12-03 CN CN202111470540.2A patent/CN114166990B/en active Active
Patent Citations (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH08318132A (en) * | 1995-05-29 | 1996-12-03 | Nisshin Steel Co Ltd | Method for denitrating waste gas and denitrator |
| WO2001055565A2 (en) * | 2000-01-26 | 2001-08-02 | Volkswagen Aktiengesellschaft | METHOD AND DEVICE FOR DETECTING A NOx CONCENTRATION OF AN EXHAUST GAS STREAM PERTAINING TO A COMBUSTION ENGINE |
| JP2002162393A (en) * | 2000-11-28 | 2002-06-07 | Mitsubishi Heavy Ind Ltd | Method and device for simultaneously analyzing nox and nh3 |
| US20110320132A1 (en) * | 2010-06-24 | 2011-12-29 | GM Global Technology Operations LLC | METHOD FOR THE DETERMINATION OF A NOx CONCENTRATION VALUE UPSTREAM OF A SCR CATALYST IN A DIESEL ENGINE |
| DE102013112567A1 (en) * | 2012-11-15 | 2014-05-15 | Ngk Spark Plug Co., Ltd. | NOx detection device and NOx sensor system |
| JP2014102098A (en) * | 2012-11-16 | 2014-06-05 | Mitsubishi Heavy Ind Ltd | System and method for diagnosing catalyst in exhaust gas denitration device |
| CN103592407A (en) * | 2013-11-07 | 2014-02-19 | 华北电力大学 | On-line power plant SCR (Selective Catalytic Reduction) denitration system catalyst activity monitoring method |
| JP2015190356A (en) * | 2014-03-28 | 2015-11-02 | 日立造船株式会社 | Method and device for measuring nox removal efficiency for engine |
| CN105547388A (en) * | 2015-12-07 | 2016-05-04 | 华北电力大学（保定） | Flue gas flow rate on-line calibration method used for desulphurization denitration control |
| US20190226382A1 (en) * | 2016-10-07 | 2019-07-25 | Cpt Group Gmbh | On-Board Diagnostics for an Exhaust Gas Catalytic Converter and Detection of Aging |
| CN107252630A (en) * | 2017-05-31 | 2017-10-17 | 国家电网公司 | A kind of method for optimizing the distribution of SCR denitration system ammonia nitrogen mol ratio |
| CN111359438A (en) * | 2020-04-09 | 2020-07-03 | 国电环境保护研究院有限公司 | Ammonia spraying optimization control method and control system for SCR flue gas denitration device |
| CN211955407U (en) * | 2020-04-09 | 2020-11-17 | 国电南京电力试验研究有限公司 | System for accurately monitoring nitrogen oxide and ammonia concentration in coal-fired flue gas in subareas |
| CN112705046A (en) * | 2020-12-16 | 2021-04-27 | 苏州西热节能环保技术有限公司 | Denitration ammonia injection fine adjustment method and device |
| CN112504994A (en) * | 2020-12-18 | 2021-03-16 | 润电能源科学技术有限公司 | Denitration flue gas concentration field on-line measuring system and denitration ammonia injection system |
| CN112697977A (en) * | 2020-12-24 | 2021-04-23 | 重庆大唐国际石柱发电有限责任公司 | Thermal power station boiler flue gas NOx index prediction method |
Non-Patent Citations (4)
| Title |
|---|
| MENGMENG YE等: "《CFD analysis of influencing factors on SCR denitration efficiency of sintering flue gas based on response surface methodology》", vol. 12, no. 07, pages 1309 - 1042 * |
| 方明成;刘玉强;王润明;周明;: "SCR脱硝系统喷氨优化调整试验研究", 华电技术, no. 09, pages 64 - 68 * |
| 赵宇;: "基于动态区域控制偏差的燃煤电厂SCR脱硝控制系统优化研究", no. 06, pages 48 - 51 * |
| 钱勇武;: "基于NO_x预测与均衡脱硝的智能喷氨系统优化控制及应用", no. 08, pages 61 - 63 * |
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