CN116571082A

CN116571082A - Ammonia injection optimization and air preheater intelligent soot blowing method and system for SCR mapping relation

Info

Publication number: CN116571082A
Application number: CN202310537892.8A
Authority: CN
Inventors: 朱玉华
Original assignee: Nanjing Yuhua Intelligent Technology Co ltd
Current assignee: Nanjing Yuhua Intelligent Technology Co ltd
Priority date: 2023-05-12
Filing date: 2023-05-12
Publication date: 2023-08-11
Anticipated expiration: 2043-05-12
Also published as: CN116571082B

Abstract

The invention provides an ammonia injection optimization and air preheater intelligent soot blowing method and system for SCR mapping relation, and relates to the field of SCR denitration. The method comprises the following steps: establishing a CFD model; dividing the areas of the ammonia spraying plane, the catalyst outlet plane and the air preheater soot blowing plane, and determining the mapping relation among all areas in the ammonia spraying plane, the catalyst outlet plane and the air preheater soot blowing plane based on a CFD model; setting a plurality of automatic regulating valves on an ammonia spraying plane, setting a plurality of NOx measuring points on a catalyst outlet plane, regulating the opening value of the automatic regulating valves according to the mapping relation between the ammonia spraying plane of any region and each region of the catalyst outlet plane, monitoring the NOx concentration value of the NOx measuring points in real time, and optimizing the ammonia spraying amount of each region of the ammonia spraying plane; and acquiring an opening value and a NOx concentration value in real time, and carrying out targeted soot blowing treatment on the area divided by the soot blowing plane of the air preheater according to the mapping relation. The invention realizes the ammonia injection optimization in the SCR denitration process and avoids the blockage of ammonia bisulfate in the air preheater.

Description

Ammonia injection optimization and air preheater intelligent soot blowing method and system for SCR mapping relation

Technical Field

The invention relates to the field of selective catalytic reduction technology (Selective Catalytic Reduction, SCR) denitration, in particular to an ammonia injection optimization and air preheater intelligent soot blowing method and system of an SCR mapping relation.

Background

In order to achieve the '3060' dual-carbon target and solve the increasingly urgent problems of energy safety, environmental deterioration, climate change and the like, china is building a clean and low-carbon energy system mainly comprising renewable energy. However, as the capacity of new energy units such as photovoltaic power generation and wind power generation is rapidly increased in the power grid, the moment of inertia of the system for keeping the frequency stable in the power grid is reduced. In order to maintain the stability of the frequency of the power grid, the role of the coal-fired power generator set in the power grid is changed, and the main power set with the basic load in the past is changed into a peak regulation and frequency modulation set. The management regulation of deep peak regulation of the thermal power unit is provided in many places, the load range of the deep regulation operation of the thermal power unit is continuously downwards regulated from 50% to 30%, even below 20%, and new challenges are presented to the operation mode of the thermal power unit.

Under the deep adjustment working condition of the unit, the operation control of the denitration system and the treatment of derivative problems are more complex, and the technical difficulties mainly exist in the following aspects:

1) Under the deep adjustment working condition, the flow field and the concentration field of the denitration system are complex and changeable, and how the area measurement and the area ammonia spraying room correspond is not easy to determine:

the complexity of the structure of the selective catalytic reduction technology (Selective Catalytic Reduction, SCR) denitration system is one of the reasons for the complexity of the denitration process mechanism. Taking 600MW unit SCR system of Dabieshan power plant as an example, the ammonia spraying plane size is 13.51X3.2 m ² The total of 21 ammonia spraying pipes and 504 nozzles are used for carrying out catalytic reaction after ammonia is sprayed and then subjected to right angle turning twice and suddenly changed to a catalyst plane with the area of 3 times of the ammonia spraying plane. Through several right angle turns and cross sectionsAfter the abrupt change, the characteristics of the flow field in the SCR reactor change greatly. Meanwhile, the distribution of NOx is uneven after passing through the catalyst layer, and the NOx is reacted in a large space in real time, for example, the catalyst plane of a 600MW unit of a Dabieshan power plant is 13.51X19.6 m ² The NOx reduction effect has yet to be further investigated.

A great deal of research work on aspects of flow field characteristics, ammonia injection regulation strategies and the like in the SCR denitration tower is carried out at home and abroad. In the researches, computational Fluid Dynamics (CFD) simulation is an effective means, and the mixing rule of the reducing agent ammonia and the flue gas is researched by analyzing the calculation results of the flow field, the component field and the like in the denitration tower. And by combining experimental research and other means, the flow field of the SCR device and NH in the flow field are improved by adopting specific measures such as arranging a guide plate at the corner of the flow field, arranging a rectifying device and an AIG partition at the upstream of the catalyst ₃ And uniformity of NOx distribution, thereby improving ammonia nitrogen distribution and matching relation. The flow field optimization of SCR can reduce the deviation of outlet NOx distribution to a certain extent, but the technical route has great limitation: ammonia action tracking and variable condition adaptability remain to be studied.

The root of the ammonia injection adjustment is that the injected ammonia can effectively perform a reduction reaction with NOx when reaching the catalyst layer, thereby reducing ammonia slip and improving denitration efficiency. Therefore, the ammonia tracing and the judgment of the NOx distribution of the catalyst layer play a guiding role in the ammonia injection optimization. In addition, once the structural optimization scheme is implemented, on-line adjustment is difficult. How to take optimal measures against the flow field and NOx distribution change caused by variable load and unstable combustion conditions of the boiler, the variable working condition adaptability of an ammonia injection model and a control strategy is still to be improved.

2) The ash blocking and soot blowing conditions of the air preheater are difficult to carry out thermal measurement:

after the ultra-clean emission is reformed, unavoidable ammonia escape can cause NH to be generated at the cold end of the downstream air preheater ₄ HSO ₄ Dust is deposited, and the dust deposition phenomenon becomes extremely serious after the machine set is deeply regulated. The characteristics of the deposited ash are different from those of loose deposited ash, the adhesive property is extremely strong, the deposited ash is difficult to remove, and meanwhile, NH ₄ HSO ₄ The strength, the position and the like of the deposition are the same as those of the unitThe charge correlation, plus the air preheater is similar to a "black box" with no NOx measurement points inside to measure soot. Therefore, the prior dust blowing of the air preheater has certain blindness and irrational property, and the damage of the heat storage plate of the air preheater is very easy to be caused, thereby affecting the safe and economic operation of a unit.

Researchers at home and abroad have been paying attention to NH generated in SCR denitration process ₄ HSO ₄ Specificity and complexity of ash deposition, and for NH ₄ HSO ₄ Research work has been carried out on the mechanism and regulation of formation. However, the research is still in the starting stage, and the following problems exist:

ammonium bisulfate, which forms ash deposits, is a viscoelastic material and its location and strength of deposit is directly related to the location and amount of ammonia slip, as well as to the operating load, flue gas temperature, i.e., the location and strength of such deposit can vary with operating conditions. Because of the particularity of the ammonium bisulfate deposited ash, the original soot blowing scheme is not applicable any more, the ammonium bisulfate deposited ash is closely related to the running condition, the position and the strength of deposited ash are continuously changed, the soot blowing scheme needs to be combined with the running condition, and the soot blowing scheme can be combined with the escaping amount and position of ammonia, and can be adjusted in time according to the running condition. The existing soot blowing method is mainly used for periodically and regularly blowing soot, the position and strength of ammonium bisulfate deposition are continuously changed along with working conditions, the existing soot blowing mode not only wastes soot blowing resources, but also hardly meets the soot blowing requirement of an air preheater with ammonium bisulfate deposition, and an intelligent soot blowing system is required to develop. I.e. the soot blowing characteristics become more complex and intelligent to be improved.

In summary, the integrated research is performed on the denitration control and ultra-clean emission derivative problems under the deep adjustment working condition of the unit, an ammonia injection total amount control platform is established, the SCR denitration theory and the ammonia injection self-adjustment control strategy and system are studied in depth, and the research on the theory, the monitoring regulation method and the system of the air preheater blocking problem caused by SCR denitration is developed comprehensively, so that the method has important practical application value in improving the denitration efficiency, reducing the ammonia escape and improving the operation safety of the air preheater.

Disclosure of Invention

The invention aims to provide an ammonia injection optimization and air preheater intelligent soot blowing method and system for SCR mapping relation, so as to solve the problem of ammonia bisulfate blockage in the air preheater in the SCR denitration process.

In order to achieve the above object, the present invention provides the following solutions:

an ammonia injection optimization and air preheater intelligent soot blowing method of an SCR mapping relation comprises the following steps:

establishing a CFD model for numerical simulation of flow fields in the SCR denitration tower, a reaction field and a flow field in the air preheater; the CFD model comprises a basic control equation, a turbulence model, a multi-component transportation model and a porous medium model; the basic control equation comprises a continuity equation, a momentum equation and an energy equation;

Dividing areas of an ammonia spraying plane, a catalyst outlet plane and an air preheater soot blowing plane, and determining mapping relations among all areas in the ammonia spraying plane, the catalyst outlet plane and the air preheater soot blowing plane based on the CFD model; the mapping relation comprises the mapping relation between the ammonia spraying plane of any region and each region divided by the catalyst outlet plane, and the mapping relation between the ammonia spraying plane of any region and each region divided by the air preheater soot blowing plane;

setting an automatic regulating valve for independently regulating the ammonia injection amount of the current ammonia injection area in each area of the ammonia injection plane division, setting a NOx measuring point in each area of the catalyst outlet plane division, regulating the opening value of the automatic regulating valve according to the mapping relation between the ammonia injection plane of any area and each area of the catalyst outlet plane division, monitoring the NOx concentration value of the NOx measuring point in real time, and optimizing the ammonia injection amount of each area of the ammonia injection plane division;

and acquiring the opening value and the NOx concentration value in real time, and carrying out targeted soot blowing treatment on the areas divided by the soot blowing plane of the air preheater according to the mapping relation among the ammonia blowing plane, the catalyst outlet plane and each area in the soot blowing plane of the air preheater.

Optionally, the area division is performed on the ammonia spraying plane, the catalyst outlet plane and the air preheater soot blowing plane, and the mapping relation among the ammonia spraying plane, the catalyst outlet plane and each area in the air preheater soot blowing plane is determined based on the CFD model, which specifically comprises the following steps:

dividing the ammonia spraying plane into a plurality of ammonia spraying areas according to an ammonia spraying pipeline;

dividing the areas of the catalyst outlet plane and the soot blowing plane of the air preheater according to the ammonia spraying area;

spraying ammonia to any ammonia spraying area, wherein the ammonia spraying amount of the remaining ammonia spraying area is 0, carrying out numerical simulation calculation on a flow field and a reaction field based on the CFD model, and determining a numerical simulation result;

tracking and calculating the travel track of the ammonia gas sprayed from the current ammonia spraying area according to the numerical simulation result;

based on the travel track, counting the ammonia spraying range and the ammonia spraying quantity of each area divided by the catalyst outlet plane, and determining the mapping relation between the ammonia spraying plane of any area and each area divided by the catalyst outlet plane;

based on the travel track, counting the ammonia spraying range and the ammonia spraying quantity of each area divided by the soot blowing plane of the air preheater, and determining the mapping relation between the ammonia spraying plane of any area and each area divided by the soot blowing plane of the air preheater.

Optionally, adjusting an opening value of the automatic adjusting valve according to a mapping relation between an ammonia injection plane of any region and each region divided by the catalyst outlet plane, and monitoring a NOx concentration value of the NOx measuring point in real time, so as to optimize an ammonia injection amount of each region divided by the ammonia injection plane, specifically including:

acquiring the NOx concentration values of all the NOx measuring points in real time;

and if the NOx concentration value of the current NOx measuring point is higher than the first average range of the NOx concentration values of all the NOx measuring points, adjusting an automatic adjusting valve of an ammonia injection region with the largest ammonia injection amount corresponding to the region where the current NOx measuring point is positioned according to the mapping relation between the ammonia injection plane of any region and each region divided by the catalyst outlet plane until the NOx concentration value of the current NOx measuring point is in the second average range of the NOx concentration values of all the NOx measuring points, returning to the step of ' monitoring the NOx concentration values of all the NOx measuring points in real time ', adjusting a plurality of automatic adjusting valves, and optimizing the ammonia injection amount of each region divided by the ammonia injection plane '.

Optionally, performing targeted soot blowing processing on the area divided by the soot blowing plane of the air preheater according to the mapping relation among the ammonia blowing plane, the catalyst outlet plane and each area in the soot blowing plane of the air preheater, which specifically includes:

If the NOx concentration value of the current NOx measuring point is higher than the first average range of the NOx concentration values of all the NOx measuring points, and the opening value of an automatic regulating valve of an ammonia spraying area in the mapping relation corresponding to the area where the current NOx measuring point is positioned is larger than the third average range of the opening values of the automatic regulating valves in all the ammonia spraying areas, starting a soot blower, and enabling the soot blower to perform soot blowing treatment on the area divided by the soot blowing plane of the air preheater corresponding to the area where the current NOx measuring point is positioned;

when the NOx concentration value of the current NOx measuring point is in a second average range of the NOx concentration values of all the NOx measuring points, stopping the soot blowing treatment of the area divided by the soot blowing plane of the air preheater corresponding to the area where the current NOx measuring point is located, and monitoring the NOx concentration value of the next NOx measuring point;

and circularly monitoring the NOx concentration values of all the NOx measuring points and the opening value of the automatic regulating valve, and carrying out targeted soot blowing treatment on the area divided by the soot blowing plane of the air preheater.

Optionally, the NOx measurement point is disposed at a central position of the area divided by the catalyst outlet plane, or the NOx measurement point is deviated from the central position.

Optionally, the first average range includes the second average range.

Optionally, the number of the areas divided by the ammonia spraying plane, the number of the areas divided by the catalyst outlet plane and the number of the areas divided by the soot blowing plane of the air preheater are equal, or the number of the areas divided by the ammonia spraying plane, the number of the areas divided by the catalyst outlet plane and the number of the areas divided by the soot blowing plane of the air preheater are unequal.

An intelligent soot blowing system of an ammonia injection optimization and air preheater of an SCR mapping relation, comprising:

the CFD model building module is used for building a CFD model for numerical simulation of the flow field in the SCR denitration tower, the reaction field and the flow field in the air preheater; the CFD model comprises a basic control equation, a turbulence model, a multi-component transportation model and a porous medium model; the basic control equation comprises a continuity equation, a momentum equation and an energy equation;

the regional division and mapping relation determination module is used for regional division of an ammonia spraying plane, a catalyst outlet plane and an air preheater soot blowing plane, and determining mapping relation among all regions in the ammonia spraying plane, the catalyst outlet plane and the air preheater soot blowing plane based on the CFD model; the mapping relation comprises the mapping relation between the ammonia spraying plane of any region and each region divided by the catalyst outlet plane, and the mapping relation between the ammonia spraying plane of any region and each region divided by the air preheater soot blowing plane;

The ammonia injection optimizing module is used for setting an automatic regulating valve for independently regulating the ammonia injection quantity of the current ammonia injection area in each area divided by the ammonia injection plane, setting a NOx measuring point in each area divided by the catalyst outlet plane, regulating the opening value of the automatic regulating valve according to the mapping relation between the ammonia injection plane of any area and each area divided by the catalyst outlet plane, monitoring the NOx concentration value of the NOx measuring point in real time, and optimizing the ammonia injection quantity of each area divided by the ammonia injection plane;

the soot blowing processing module is used for acquiring the opening value and the NOx concentration value in real time, and carrying out targeted soot blowing processing on the areas divided by the soot blowing plane of the air preheater according to the mapping relation among the ammonia blowing plane, the catalyst outlet plane and each area in the soot blowing plane of the air preheater.

An electronic device comprising a memory and a processor, the memory being configured to store a computer program, the processor being configured to run the computer program to cause the electronic device to perform the SCR mapping method of ammonia injection optimization and air preheater intelligent soot blowing described in any of the above.

A computer readable storage medium storing a computer program which when executed by a processor implements the ammonia injection optimization and air preheater intelligent soot blowing method of the SCR mapping relationship of any one of the above.

According to the specific embodiment provided by the invention, the invention discloses the following technical effects: the invention provides an ammonia spraying optimization of an SCR mapping relation and an intelligent soot blowing method and system of an air preheater, which are used for dividing areas of an ammonia spraying plane, a catalyst outlet plane and an air preheater soot blowing plane, providing a concept of 'mapping relation' of ammonia nitrogen, determining the mapping relation between the reaction position of the ammonia spraying position and a catalyst layer (namely the reaction for reducing NOx) and the soot blowing position of the air preheater based on the divided areas, guiding an SCR denitration reactor to perform ammonia spraying adjustment and downstream equipment of the SCR denitration reactor to perform soot blowing treatment, achieving the aims of denitration optimization and comprehensive treatment of ammonia hydrogen sulfate blocking of the air preheater, and avoiding the ammonia hydrogen sulfate blocking in the air preheater in the SCR denitration process.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings that are needed in the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart of an intelligent soot blowing method of an air preheater and ammonia injection optimization of an SCR mapping relation provided by an embodiment of the invention;

FIG. 2 is a schematic diagram of an SCR reactor and an air preheater according to a second embodiment of the present invention;

FIG. 3 is a flow chart of an intelligent soot blowing method of an air preheater and ammonia injection optimization of an SCR mapping relationship provided by a second embodiment of the invention;

FIG. 4 is a graph showing ammonia tracing and mapping relationship in the area A1 of the ammonia spraying plane of the embodiment;

FIG. 5 is a mapping relationship diagram of an ammonia injection plane, a catalyst outlet plane and an air preheater soot blowing plane in an embodiment.

Detailed Description

The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.

The invention aims to provide an ammonia injection optimization and air preheater intelligent soot blowing method and system for SCR mapping relation, which realize ammonia injection optimization in the SCR denitration process and avoid ammonia bisulfate blockage in the air preheater in the SCR denitration process.

In order that the above-recited objects, features and advantages of the present invention will become more readily apparent, a more particular description of the invention will be rendered by reference to the appended drawings and appended detailed description.

In the prior art, even though the technology of zoning ammonia injection is adopted, namely the ammonia geometric area of an ammonia injection pipeline or the construction difficulty level is zoned, the ammonia injection is mostly adjusted according to the geometric mapping relation when the ammonia injection is actually operated. That is, when the NOx at a certain measuring point on the rear plane of the catalyst reaction is high, the ammonia injection valve corresponding to the geometry is adjusted. However, this adjustment is inaccurate because not only a 90 ° vertical turn, but also abrupt cross-sectional changes in the ammonia injection plane and catalyst plane in the SCR geometry result in diffusion of ammonia, and each SCR reactor is different. Therefore, the mapping relation between the ammonia injection plane and the catalyst reaction plane is summarized, so that a more accurate ammonia injection regulation strategy is formulated, and the optimization regulation can be more effectively carried out, so that the denitration efficiency is improved, and the ammonia injection quantity and the ammonia escape are reduced.

The prior air preheater blows ash without partition, and only blows ash evenly at regular time, such as three times a day, and each time the soot blower is moved to blow ash evenly. The soot blowing mode cannot strengthen soot blowing for the area which is easy to generate ammonia bisulfate blocking ash, and cannot change according to the operation condition. In fact, the ash blocking of the ammonia bisulfate is caused by excessive ammonia spraying, so that the area with excessive ammonia spraying is found to carry out fixed-point ash blowing, and the pertinence and the effectiveness of ash blowing can be improved.

Example 1

As shown in FIG. 1, the invention provides an ammonia injection optimization and air preheater intelligent soot blowing method of an SCR mapping relation, which comprises the following steps:

step 101: establishing a computational fluid dynamics (Computational Fluid Dynamics, CFD) model of numerical simulation of flow fields in the SCR denitration tower, a reaction field and an air preheater; the CFD model comprises a basic control equation, a turbulence model, a multi-component transportation model and a porous medium model; the basic control equations include a continuity equation, a momentum equation, and an energy equation.

The CFD model includes flow, heat transfer, chemical reaction, etc., and generally, CFD calculation software such as Fluent is applied to build a geometric model first, select a calculation model in the software, set parameters, and calculate.

Step 102: dividing areas of an ammonia spraying plane, a catalyst outlet plane and an air preheater soot blowing plane, and determining mapping relations among all areas in the ammonia spraying plane, the catalyst outlet plane and the air preheater soot blowing plane based on the CFD model; the mapping relation comprises the mapping relation between the ammonia spraying plane of any region and each region divided by the catalyst outlet plane, and the mapping relation between the ammonia spraying plane of any region and each region divided by the air preheater soot blowing plane.

In practical application, the step 102 specifically includes: dividing the ammonia spraying plane into a plurality of ammonia spraying areas according to an ammonia spraying pipeline; dividing the areas of the catalyst outlet plane and the soot blowing plane of the air preheater according to the ammonia spraying area; spraying ammonia to any ammonia spraying area, wherein the ammonia spraying amount of the remaining ammonia spraying area is 0, carrying out numerical simulation calculation on a flow field and a reaction field based on the CFD model, and determining a numerical simulation result; tracking and calculating the travel track of the ammonia gas sprayed from the current ammonia spraying area according to the numerical simulation result; based on the travel track, counting the ammonia spraying range and the ammonia spraying quantity of each area divided by the catalyst outlet plane, and determining the mapping relation between the ammonia spraying plane of any area and each area divided by the catalyst outlet plane; based on the travel track, counting the ammonia spraying range and the ammonia spraying quantity of each area divided by the soot blowing plane of the air preheater, and determining the mapping relation between the ammonia spraying plane of any area and each area divided by the soot blowing plane of the air preheater.

Dividing an ammonia spraying plane into n areas according to the characteristics of an ammonia spraying pipeline, wherein n can be 4-24; the catalyst outlet plane (the plane after the catalyst reaction) is divided into N areas, wherein N can be 4-24, and N can be equal to or different from N; the soot blowing area (soot blowing plane) of the air preheater is divided into M areas, wherein M can be 4-24, and M can be equal to N and N or not.

The following cycles were performed:

(1) Only the ith area sprays ammonia, and other areas do not spray ammonia, namely the ammonia spraying amount of other areas is 0; the ith area is an ammonia spraying area divided by an ammonia spraying plane.

(2) And (3) carrying out numerical simulation calculation of the flow field and the reaction field by using the calculation method in the step (101) to obtain a numerical simulation result.

(3) Tracking and calculating the travel track of ammonia sprayed from the current zone (i zone), and counting the range and the quantity of the ammonia falling on the rear plane of the catalyst layer reaction to obtain the mapping relation between the ammonia sprayed from the i zone and N zones of the catalyst outlet plane (the rear plane of the catalyst layer reaction); counting the quantity and the range of ammonia falling on M areas of a soot blowing plane of the air preheater, so as to obtain the mapping relation among the ammonia spraying plane, a catalyst outlet plane and each area of the soot blowing plane of the air preheater; the mapping relation comprises a mapping relation between an ith area ammonia spraying plane and a catalyst outlet plane and a mapping relation between the ith area ammonia spraying plane and an air preheater soot blowing plane.

The above calculation is looped until i=n ends.

Step 103: an automatic regulating valve for independently regulating the ammonia injection amount of the current ammonia injection area is arranged in each area of the ammonia injection plane division, an NOx measuring point is arranged in each area of the catalyst outlet plane division, the opening value of the automatic regulating valve is regulated according to the mapping relation between the ammonia injection plane of any area and each area of the catalyst outlet plane division, the NOx concentration value of the NOx measuring point is monitored in real time, and the ammonia injection amount of each area of the ammonia injection plane division is optimized.

In practical application, the step 103 specifically includes: acquiring the NOx concentration values of all the NOx measuring points in real time; and if the NOx concentration value of the current NOx measuring point is higher than the first average range of the NOx concentration values of all the NOx measuring points, adjusting an automatic adjusting valve of an ammonia injection region with the largest ammonia injection amount corresponding to the region where the current NOx measuring point is positioned according to the mapping relation between the ammonia injection plane of any region and each region divided by the catalyst outlet plane until the NOx concentration value of the current NOx measuring point is in the second average range of the NOx concentration values of all the NOx measuring points, returning to the step of ' monitoring the NOx concentration values of all the NOx measuring points in real time ', adjusting a plurality of automatic adjusting valves, and optimizing the ammonia injection amount of each region divided by the ammonia injection plane '.

In practical application, the ammonia injection optimization method comprises the following steps:

(1) The ammonia spraying pipeline is provided with n automatic regulating valves corresponding to n areas of the ammonia spraying plane, each valve can independently regulate the ammonia spraying amount of the area, such as the ith valve, and the ammonia spraying amount of the ith area can be independently regulated.

(2) N NOx measuring points are arranged on the plane of the catalyst outlet and respectively arranged in N zones, wherein the measuring points can be arranged at the central position of the N zone or can be deviated from the center.

(3) And obtaining the NOx values of N measuring points of the catalyst outlet plane in real time.

If the NOx value of the I-th measuring point is higher than the average value of N measuring points by plus or minus 20%, the automatic valve in the ammonia injection plane area with the largest ammonia amount in the I-th area is adjusted according to the mapping relation obtained in the step 102 until the NOx value is close to the average value within 10%. Wherein, 20% of the judging standard during the adjustment can be changed, the changing range can be 5% -30%, 10% of the judging standard for stopping the automatic valve and the soot blowing can be changed, and the changing range is 0% -20%.

(4) Repeating the operation of the step (3), monitoring N measuring points in real time and adjusting N valves to achieve the aim of optimizing ammonia injection.

Step 104: and acquiring the opening value and the NOx concentration value in real time, and carrying out targeted soot blowing treatment on the areas divided by the soot blowing plane of the air preheater according to the mapping relation among the ammonia blowing plane, the catalyst outlet plane and each area in the soot blowing plane of the air preheater.

In practical applications, the step 104 specifically includes: if the NOx concentration value of the current NOx measuring point is higher than the first average range of the NOx concentration values of all the NOx measuring points, and the opening value of an automatic regulating valve of an ammonia spraying area in the mapping relation corresponding to the area where the current NOx measuring point is positioned is larger than the third average range of the opening values of the automatic regulating valves in all the ammonia spraying areas, starting a soot blower, and enabling the soot blower to perform soot blowing treatment on the area divided by the soot blowing plane of the air preheater corresponding to the area where the current NOx measuring point is positioned; when the NOx concentration value of the current NOx measuring point is in a second average range of the NOx concentration values of all the NOx measuring points, stopping the soot blowing treatment of the area divided by the soot blowing plane of the air preheater corresponding to the area where the current NOx measuring point is located, and monitoring the NOx concentration value of the next NOx measuring point; and circularly monitoring the NOx concentration values of all the NOx measuring points and the opening value of the automatic regulating valve, and carrying out targeted soot blowing treatment on the area divided by the soot blowing plane of the air preheater.

In practical application, the method for integrally treating the ammonia bisulfate blocking ash of the air preheater comprises the following steps:

(1) And obtaining the opening values of N valves of the ammonia injection plane and the NOx values of N measuring points of the catalyst outlet plane in real time.

(2) If the I NOx measured value of the outlet plane is judged to be smaller than 20% of the average value of all the areas by 1, and the valve opening of the ammonia spraying area of the ammonia spraying plane in the mapping relation corresponding to the I area is judged to be larger than the average value of the valve opening of all the areas by 1, the soot blower is started, and an instruction is sent to move the soot blower to the soot blowing plane area of the air preheater corresponding to the I area of the catalyst outlet plane in the mapping relation to perform soot blowing.

(3) Stopping soot blowing in the zone when the NOx measurement value of the I-th outlet plane is within 10% of the average value of each zone; the monitoring of the next exit station is performed.

(4) And (3) circularly monitoring N measuring points of the catalyst outlet and N valves of the ammonia spraying plane to perform targeted soot blowing on demand in real time, thereby achieving the purpose of removing the ammonia bisulfate blocking ash generated by ammonia escape in real time.

In practical application, the NOx measurement point is arranged at the central position of the area divided by the catalyst outlet plane, or the NOx measurement point deviates from the central position.

In practical applications, the first average range includes the second average range.

In practical application, the number of the areas divided by the ammonia spraying plane, the number of the areas divided by the catalyst outlet plane and the number of the areas divided by the soot blowing plane of the air preheater are equal, or the number of the areas divided by the ammonia spraying plane, the number of the areas divided by the catalyst outlet plane and the number of the areas divided by the soot blowing plane of the air preheater are unequal.

Example two

Taking an SCR reactor and an air preheater of a certain power plant as examples, a mapping relation is established according to the invention, and ammonia injection optimization and air preheater blocking integrated treatment are carried out.

The SCR reactor is provided with three layers of catalysts, and the flue gas entering the SCR from the outlet of the economizer (SCR upstream equipment) firstly flows through the flue of the inclined section and the vertical section and then enters the catalyst layer of the SCR reactor. The flue section size of the inclined section and the vertical section is 4.6mx16m, the section size of the catalyst layer is 16mx16m, the size of the plane (catalyst outlet plane) after the SCR catalyst is reacted is 6.4mx16m, and the soot blowing plane size of the air preheater is a semicircle with the size of phi 6.4 m. The specific structure is shown in fig. 2.

In fig. 2, the ammonia injection plane is the plane a, and the catalyst reaction rear plane, i.e., the catalyst outlet plane, is the plane B; meanwhile, the measuring points of NOx are also arranged on the plane B, so the plane B is also the measuring point plane; the soot blowing plane of the air preheater is a C plane.

As shown in fig. 3, the specific steps are as follows.

Step 1: and establishing a numerical simulation calculation model of flow fields in the SCR denitration tower and the air preheater.

The mixed transportation process of reactants in the SCR reactor is described by adopting a multicomponent material transportation model. Turbulent flow of the flue gas is described by adopting a standard k-epsilon double equation; the simulation of the catalyst layer adopts a porous medium model to describe the diffusion and reaction process of components in the solid wall area of the catalyst.

The invention combines the models and mechanisms to construct the SCR denitration reactor and the air preheater internal flow model.

The basic control equation has mass conservation, momentum conservation and energy conservation, and is the basis of the following models; the turbulence equation is used when calculating the turbulence flow field, but the SCR and the air preheater are usually the turbulence flow field, that is to say, the basic flow process needs a basic control equation and a turbulence equation; the multicomponent transportation model is adopted because ammonia sprayed in SCR and NO in flue gas are different components, and the transportation process between the ammonia and the NO in the flue gas is calculated; the porous medium model is a specific calculation method for simulating the arrangement space of the heat exchange elements in the catalyst layer of the SCR and the air preheater, and can simulate the flow resistance of the part.

The links between the four models: the continuity equation and the turbulence equation are the basis of the latter two models, wherein the continuity equation is the basis of the turbulence equation; component transport can also be calculated without porous media, but the resistance loss and flow field calculations between the catalyst section and the air preheater heat exchange element section would not be practical, thus requiring the four models described above to work together.

1. The basic control equation specifically includes:

(1) Continuity equation

The continuity equation is an expression for conservation of mass in fluid mechanics. The composition s in the mixed gas changes its density ρ with time and distance due to chemical reaction. R is R _S Is the rate of formation of component s per unit volume due to chemical reaction, R _S ＝▽(ρ _S υ _S ) The unit is kg/(m) ³ S). Under a unitary rectangular coordinate system, a control body is taken along the flow direction of the x axis, and the mass flow of the inflow control body minus the mass flow of the outflow control body plus the generation rate is equal to the increase rate of the mass in the control body according to the mass conservation principle. Thus, for component s, the continuity equation is:

wherein m is _s The mass fraction of the chemical component s is defined as:

g and ρ are the total mass flow and density of the mixed gas, and the expressions are:

Γ _s the transport coefficient for chemical component s:

Γ _s ＝ρD _s

wherein D is _s Is the diffusion coefficient of the chemical component s in the mixed gas.

In three-dimensional flow, m _s Gradient in all three directions, assuming diffusion coefficient D _s The continuity equation can be written as:

wherein R is _s Is a source item. Continuity for the whole mixed gasThe equation is still:

for a steady-state flow,therefore(s)>This means that G is not time and space dependent, so the continuity equation for steady state flow can be written as:

(2) Momentum equation

The momentum of the gas mixing process in the SCR reactor is also conserved, and the momentum change of the fluid microcell over time is equal to the sum of the forces acting on the fluid microcell for all external conditions. The conservation of momentum (N-S) equations in different directions of the coordinate system are:

x direction:

y direction:

and Z direction:

(3) Energy equation

The gas mixing process within the SCR reactor has various energy exchanges, so conservation of energy is also followed, i.e. the increase in energy inside the fluid cells is equal to the sum of the net increase in heat flow into the fluid cells and the work done by the force between the surfaces on the fluid cells. The following equation is the conservation of energy:

ρ _g representing fluid density; t is time;is the fluid velocity; u, v, w are the average velocity of the fluid in the x, y, z directions; mu (mu) _g Represents the dynamic viscosity of the fluid; θ is the stress to which the fluid is subjected; s is S _u 、S _v 、S _w Representing the deformation velocity tensors of the fluid in the x, y and z directions, respectively; c _p Representing the constant pressure specific heat capacity of the fluid; lambda (lambda) _g Representing the thermal conductivity of the fluid; s is S _T Representing its viscous dissipation term.

2. Turbulence equation

The flue gas flow in the flue belongs to turbulent flow. The determination of the turbulence viscosity coefficient mu requires the aid of turbulence models, many of which have been proposed so far and applied in calculations, and relatively advanced models are still under development. The invention selects a standard k-epsilon model to describe the turbulent motion of the smoke.

For the two equation model, the turbulence viscosity coefficient is expressed as:

wherein: c (C) _μ Is a model constant, C _μ =0.09; k and ε are turbulence kinetic energy and turbulence kinetic energy dissipation ratio, respectively, defined as:

the equation form of k and ε in the standard k- ε equation is:

the model constants of the formula are: c (C) ₁ ＝1.44；C ₂ ＝1.92；σ _k ＝1.0；σ _ε ＝1.3。

Generation of turbulent kinetic energy:

the transport equations for the variables (u, v, w, e, k, ε) are identical in terms of equations, and thus can be described using a unified form:

wherein: Γ -shaped structure ^φ And S is ^φ The effective diffusion coefficient and the source item corresponding to each variable are respectively obtained. Γ of the respective variables ^φ And S is ^φ The expression of (2) is shown in Table 1.

Table 1 diffusion coefficient and Source expression Meter

3. Multicomponent transport model

The presence of various components in the SCR reactor, e.g. NO, NH ₃ 、O ₂ And the like, the invention adopts a multicomponent substance transportation model to simulate the mixing process among various components in the flowing process, and the mixed transportation of substances is simulated by solving the convection, diffusion and conservation equation of a reaction source of the mixed substances. The principle of solving the conservation equation of the chemical substance is to calculate the mass fraction of each substance by using the convection diffusion equation of the ith substance, and the general form of the conservation equation is as follows:

wherein R is _i Is the net rate of production of the chemical reaction; s is S _i Is the discrete phase and the additional rate of generation caused by the user-defined source term. Assuming that n substances are contained in the system, then n-1 equations need to be solved. The mass fraction of the nth species is obtained by subtracting the mass fraction of the first n-1 species. Therefore, in order to reduce numerical errors occurring in the calculation as much as possible, it is necessary to define the substance having the largest mass fraction as the nth substance. When Fluent sets the mixed gas component of SCR denitration reaction, N ₂ As the substance with the largest mass fraction, N is ensured ₂ Located at the last of the list.

In turbulent flow, the mass diffusion flux is:

wherein D is _i,m Representing the diffusion coefficient, SC, of the i-th substance in the mixture _t Is schmitt number.

4. Porous media model

For SCR heterogeneous catalytic reactions, the flow and reaction process within the catalyst layer occurs not only on the surface layer of the catalyst solid wall, but also deep in the catalyst void. The method widely used by the scholars is to replace the catalyst layer with a porous medium model. The porous medium model is characterized in that fluid and solid are drawn into the same control body, the effect of the solid in a flow area on the flow is regarded as resistance added to the fluid, and the influence of the solid on the flow is characterized by modifying a control differential equation set.

After the porous medium model is adopted, the flow of air among the tube bundles is equivalent to the uniform flow containing solid barriers, and the equivalent flow area and flow passage area are consistent with those of the original flow passages. The influence of solid barriers on the flow is considered by the porous resistance coefficient, so that the number of grids and the calculated amount can be reduced, and the flow and the pressure drop in the heat exchange surface can be reliably simulated.

The porous media model simply adds a loss of momentum in the momentum equation as a source term to the momentum equation for the effects of different flow characteristics and geometries on fluid flow. The source item consists of two parts: one part is the viscous drag coefficient; the other part is the inertial resistance coefficient. Source item S _i Can be expressed as:

wherein S is _i Is an i-directional (x, y, z) momentum source term; d (D) _ij 、C _ij Is a matrix of viscosity and inertial resistance coefficients; μ is the fluid viscosity; ρ is the fluid density; v _j And j is the fluid velocity. The source term directly causes a change in the pressure gradient distribution within the porous medium. Thus, the pressure drop is proportional to the velocity.

For a simple homogeneous porous medium:

wherein alpha is permeability, C ₂ Is the inertial resistance factor, constant C ₂ Can be seen as a loss factor per unit length along the flow direction.

The invention simplifies the catalyst solid wall area into a porous medium area, and the pressure loss generated by fluid passing through the porous medium layer is described as follows according to an Ergun semi-empirical formula taking a fiber ball filter as a model:

the expression for the viscous drag coefficient and the inertial drag coefficient can be further deduced as:

wherein K represents a viscous drag coefficient; epsilon is the porosity; d (D) _P Is the average particle diameter.

The average particle size of the catalyst can be calculated by a body-centered cubic stacking structure calculation model to obtain the corresponding average particle size value of the catalyst under different porosities. The viscous drag coefficient and the inertial drag coefficient in the porous medium model can be obtained by taking the obtained parameters into the expression of the viscous drag coefficient and the inertial drag coefficient.

It should be noted that for a monolithic SCR denitration reactor, the catalyst zone is entirely represented by the porous media zone. In the direction perpendicular to the flue gas flow direction, the gas flow has to pass through the catalyst wall surface, but in the direction parallel to the flue gas flow direction, the gas flow is not blocked by the wall surface, so that the porous medium parameters in the SCR full-size reactor are set to be anisotropic.

Step 2: mapping relation:

the ammonia injection plane (plane a) is divided into n=8 zones (i.e., A1-A8 in fig. 5) according to the ammonia injection line characteristics.

The catalyst outlet plane (the post-catalyst reaction plane, also the arrangement plane of the outlet NOx measurement points, abbreviated as measurement point plane, B plane) is divided into n=8 zones (i.e., B1-B8 in fig. 5).

The soot blowing plane (C plane) of the air preheater is also divided into m=8 zones (i.e., C1-C8 in fig. 5), m=n=n=8 in this embodiment.

The following cycles were performed:

(1) First i=1.

(2) The ammonia spraying plane only sprays ammonia in the i=1 zone, and other zones do not spray ammonia, namely the ammonia spraying amount in other zones is 0.

(3) And (3) carrying out numerical simulation calculation of the flow field and the reaction field by using the calculation method in the step (1) to obtain a numerical simulation result.

(4) Tracking and calculating the travel track of ammonia sprayed from the current zone (i=1 zone), and counting the range and the number of the ammonia sprayed from the i=1 zone and the ammonia sprayed from the catalyst outlet plane (B plane) N=8 zones, wherein the range and the number of the ammonia sprayed from the i=1 zone are counted and fall on the plane (measuring point plane) after the reaction of the catalyst layer; the amount and extent of ammonia falling on the air preheater sootblowing plane (C-plane) m=8 zones were counted, and the mapping relationship between the ammonia injection plane, the catalyst outlet plane and each zone of the air preheater sootblowing plane was obtained as shown in fig. 4.

(5) The above calculation is circulated until i=n is over, and the mapping relation between the catalyst outlet plane (B plane) and the ammonia injection plane (a plane) and the soot blowing plane (C plane) of the air preheater is obtained, as shown in fig. 5.

Step 3: the ammonia spraying optimization method comprises the following steps:

(1) The ammonia spraying pipeline is provided with an automatic regulating valve corresponding to 8 areas of an ammonia spraying plane (A plane), namely 8 automatic regulating valves are arranged, each valve can independently regulate the ammonia spraying amount of the area, such as an ith valve, and can independently regulate the ammonia spraying amount of the ith area.

(2) In the catalyst outlet plane (B plane), 8 NOx measurement points are arranged, which are respectively arranged in 8 zones, and the measurement points may be arranged in the center position of the zones.

(3) And obtaining the NOx values of 8 zone measuring points of the B plane in real time.

And if the NOx value of the measuring point in the I zone is 20% higher than the average value of 8 measuring points of the B plane, adjusting an automatic valve in the ammonia injection zone with the largest ammonia amount in the I zone according to the mapping relation obtained in the step 2. For example, if the NOx value in the B1 zone is higher than 20% of the average value of 8 measuring points on the B plane, the ammonia injection valve in the A1 zone is opened until the NOx value at the inner point of the B1 zone falls within 10% deviation of the average value.

(4) Repeating the operation of the step (3), monitoring 8 measuring points of the plane B and adjusting 8 valves of the plane A in real time, and achieving the purpose of optimizing ammonia injection.

Step 4: and (3) the ammonia bisulfate ash blocking of the air preheater is treated integrally.

The opening values of 8 valves of the ammonia injection plane (A plane) and the NOx values of 8 measuring points of the catalyst outlet plane (B plane) are obtained in real time.

If the measured value of NOx of the I-th outlet plane is judged to be smaller than 20% of the average value of all the areas, and the valve opening of the ammonia spraying area of the ammonia spraying plane in the mapping relation corresponding to the I-th area is larger than 20% of the average value of the valve opening of all the areas, starting the soot blower, and sending an instruction to move the soot blower to the soot blowing plane area of the air preheater corresponding to the I-th area of the catalyst outlet plane in the mapping relation to perform soot blowing; for example, if it is determined that the NOx measurement value of the B1 zone is less than 20% of the average value of the zones, and the valve opening of the ammonia spraying zone of the ammonia spraying plane A1 zone in the mapping relationship corresponding to the first zone is greater than 20% of the average value of the valve opening of the zones, the soot blower is started, and an instruction is sent to move the soot blower to the corresponding air preheater soot blowing plane C2 zone in the mapping relationship to perform soot blowing.

Stopping soot blowing in the zone when the NOx measurement value of the I-th outlet plane is within 10% of the average value of each zone; the monitoring of the next exit station is performed.

And 8 measuring points on the plane B of the catalyst outlet and 8 valves on the plane A of the ammonia spraying plane are monitored in a circulating way to perform targeted soot blowing on demand in real time, so that the purpose of removing the ammonia bisulfate blocking ash generated by ammonia escape in real time is achieved.

Example III

In order to execute the method corresponding to the embodiment to realize the corresponding functions and technical effects, an ammonia injection optimization and air preheater intelligent soot blowing system of the SCR mapping relation is provided below.

Example IV

The embodiment of the invention provides electronic equipment which comprises a memory and a processor, wherein the memory is used for storing a computer program, and the processor runs the computer program to enable the electronic equipment to execute the ammonia injection optimization and air preheater intelligent soot blowing method of the SCR mapping relation provided in the embodiment I.

In practical applications, the electronic device may be a server.

In practical applications, the electronic device includes: at least one processor (processor), memory (memory), bus, and communication interface (Communications Interface).

Wherein: the processor, communication interface, and memory communicate with each other via a communication bus.

And the communication interface is used for communicating with other devices.

And a processor, configured to execute a program, and specifically may execute the method described in the foregoing embodiment.

In particular, the program may include program code including computer-operating instructions.

The processor may be a central processing unit, CPU, or specific integrated circuit ASIC (Application Specific Integrated Circuit), or one or more integrated circuits configured to implement embodiments of the present application. The one or more processors included in the electronic device may be the same type of processor, such as one or more CPUs; but may also be different types of processors such as one or more CPUs and one or more ASICs.

And the memory is used for storing programs. The memory may comprise high-speed RAM memory or may further comprise non-volatile memory, such as at least one disk memory.

Based on the description of the above embodiments, an embodiment of the present application provides a storage medium having stored thereon computer program instructions executable by a processor to implement the method of any embodiment

The ammonia injection optimization and air preheater intelligent soot blowing system of the SCR mapping relation provided by the embodiment of the application exists in various forms, including but not limited to:

(1) A mobile communication device: such devices are characterized by mobile communication capabilities and are primarily aimed at providing voice, data communications. Such terminals include: smart phones (e.g., iPhone), multimedia phones, functional phones, and low-end phones, etc.

(2) Ultra mobile personal computer device: such devices are in the category of personal computers, having computing and processing functions, and generally having mobile internet access capabilities. Such terminals include: PDA, MID, and UMPC devices, etc., such as iPad.

(3) Portable entertainment device: such devices may display and play multimedia content. The device comprises: audio, video players (e.g., iPod), palm game consoles, electronic books, and smart toys and portable car navigation devices.

(4) Other electronic devices with data interaction functions.

Thus, particular embodiments of the present subject matter have been described. Other embodiments are within the scope of the following claims. In some cases, the actions recited in the claims can be performed in a different order and still achieve desirable results. In addition, the processes depicted in the accompanying figures do not necessarily require the particular order shown, or sequential order, to achieve desirable results. In some embodiments, multitasking and parallel processing may be advantageous.

The system, apparatus, module or unit set forth in the above embodiments may be implemented in particular by a computer chip or entity, or by a product having a certain function. One typical implementation is a computer. In particular, the computer may be, for example, a personal computer, a laptop computer, a cellular telephone, a camera phone, a smart phone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

For convenience of description, the above devices are described as being functionally divided into various units, respectively. Of course, the functions of each element may be implemented in the same piece or pieces of software and/or hardware when implementing the present application. It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In one typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include volatile memory in a computer-readable medium, random Access Memory (RAM) and/or nonvolatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). Memory is an example of computer-readable media.

Computer readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of a storage medium for a computer include, but are not limited to, a phase change memory (PRAM), a Static Random Access Memory (SRAM), a Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), a Read Only Memory (ROM), an Electrically Erasable Programmable Read Only Memory (EEPROM), a flash memory or other memory technology, a compact disc read only memory (CD-ROM), a compact disc Read Only Memory (ROM),

Digital Versatile Disk (DVD) or other optical storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices

Or any other non-transmission medium, may be used to store information that may be accessed by a computing device. The computer readable medium, as defined in the present invention, does not include transitory computer readable media (transmission media), such as modulated data signals and carrier waves.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article or apparatus that comprises the element.

The application may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular transactions or implement particular abstract data types. The application may also be practiced in distributed computing environments where transactions are performed by remote processing devices that are connected through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.

In the present specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different point from other embodiments, and identical and similar parts between the embodiments are all enough to refer to each other. For the system disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant points refer to the description of the method section.

The principles and embodiments of the present application have been described in detail with reference to specific examples, which are provided to facilitate understanding of the method and core ideas of the present application; also, it is within the scope of the present application to be modified by those of ordinary skill in the art in light of the present teachings. In view of the foregoing, this description should not be construed as limiting the application.

Claims

1. An ammonia injection optimization and air preheater intelligent soot blowing method of an SCR mapping relation is characterized by comprising the following steps:

2. The method for optimizing ammonia injection and intelligently blowing ash in an air preheater according to the SCR mapping relation of claim 1, wherein the method for dividing the areas of the ammonia injection plane, the catalyst outlet plane and the air preheater blowing ash plane and determining the mapping relation among the areas in the ammonia injection plane, the catalyst outlet plane and the air preheater blowing ash plane based on the CFD model specifically comprises the following steps:

3. The intelligent soot blowing method of an ammonia injection optimization and air preheater of the SCR mapping relation according to claim 1, wherein the opening value of the automatic regulating valve is regulated according to the mapping relation between the ammonia injection plane of any region and each region divided by the catalyst outlet plane, the NOx concentration value of the NOx measuring point is monitored in real time, and the ammonia injection amount of each region divided by the ammonia injection plane is optimized, specifically comprising:

4. The method for optimizing ammonia injection and intelligently blowing ash of an air preheater according to the SCR mapping relation of claim 1, wherein the specific soot blowing processing is performed on the areas divided by the air preheater soot blowing plane according to the mapping relation among the ammonia injection plane, the catalyst outlet plane and the areas in the air preheater soot blowing plane, specifically comprising:

5. The intelligent soot blowing method of an SCR mapping relation for ammonia injection optimization and an air preheater according to claim 1, wherein said NOx measuring point is disposed at a central position of a region divided by said catalyst outlet plane, or said NOx measuring point is deviated from said central position.

6. The method for optimizing ammonia injection and intelligent soot blowing by an air preheater according to the SCR mapping relationship of claim 3 or 4, wherein said first average range comprises said second average range.

7. The method for optimizing ammonia injection and intelligently blowing ash by an air preheater according to the SCR mapping relation of claim 1, wherein the number of areas divided by the ammonia injection plane, the number of areas divided by the catalyst outlet plane and the number of areas divided by the blowing ash plane of the air preheater are equal, or the number of areas divided by the ammonia injection plane, the number of areas divided by the catalyst outlet plane and the number of areas divided by the blowing ash plane of the air preheater are all unequal.

8. An intelligent soot blowing system of an ammonia injection optimization and air preheater of an SCR mapping relation is characterized by comprising the following components:

9. An electronic device comprising a memory and a processor, the memory configured to store a computer program, the processor configured to execute the computer program to cause the electronic device to perform the SCR mapping method of any one of claims 1-7.

10. A computer readable storage medium, characterized in that it stores a computer program, which when executed by a processor implements the ammonia injection optimization and air preheater intelligent soot blowing method of SCR mapping according to any one of claims 1-7.