CN111779578B

CN111779578B - Gas turbine NOx emission prediction system and prediction method

Info

Publication number: CN111779578B
Application number: CN202010672652.5A
Authority: CN
Inventors: 袁奇; 陈劼; 卢桂贤; 李波
Original assignee: Nanjing Ruihua Power Technology Co ltd
Current assignee: Helis Filter Nanjing Co ltd
Priority date: 2020-07-14
Filing date: 2020-07-14
Publication date: 2023-01-06
Anticipated expiration: 2040-07-14
Also published as: CN111779578A

Abstract

The invention discloses a gas turbine NOx emission prediction system, which consists of a gas turbine, a waste heat boiler, a power plant existing control system, a controller and a remote server, wherein the gas turbine is connected with the waste heat boiler through a pipeline, the power plant existing control system and the controller control the operation of the gas turbine and the waste heat boiler and carry out remote service operation through the remote server, the gas turbine comprises a gas compressor, a combustion chamber, a turbine and a generator, and the gas compressor, the combustion chamber, the turbine and the generator are rigidly connected. According to the method, the NOx emission value of the gas turbine is predicted based on an emission model formed by historical data related to NOx emission during combustion adjustment according to environmental conditions or weather forecast, and preventive preparation is made or the emission value is monitored according to the emission prediction, so that the aims of predicting and pertinently processing the NOx emission of the gas turbine are fulfilled.

Description

Gas turbine NOx emission prediction system and prediction method

Technical Field

The invention relates to the technical field of gas turbines, in particular to a system and a method for predicting NOx emission of a gas turbine.

Background

In order to meet the boundary condition requirements of stable combustion, high efficiency, low NOx emission and the like of the gas turbine, the fuel quantity and air quantity ratio entering a combustion chamber of the gas turbine need to be adjusted seasonally and periodically, and the setting values of physical quantities such as a fuel valve position, an air valve position and the like are determined. The adjustment runs through each load stage of the gas turbine from grid connection to full load operation, and ensures that the operation condition during setting meets the requirement of boundary condition limitation.

However, the existing gas turbine has the following problems during operation and use: (1) With the lapse of the running time, the environmental conditions will change continuously, the set value during the combustion adjustment will not be suitable for the new environmental conditions completely, resulting in the emission of NOx exceeding the environmental protection regulation requirements; (2) In addition, due to the inherent characteristics of some gas turbines, NOx is always in an overproof emission state, and in order to ensure that the emission reaches the standard, a denitration system is arranged at the tail section of the HRSG to reduce the emission of the NOx, but due to the large inertia and the nonlinear characteristics of the denitration system and the hysteresis of the existing online measurement of the NOx, the phenomena of delayed ammonia injection control, over-injection and high ammonia escape rate often occur. For this reason, a corresponding technical scheme needs to be designed to solve the existing technical problems.

Disclosure of Invention

The invention aims to provide a system and a method for predicting NOx emission of a gas turbine, which solve the technical problems that environmental conditions can continuously change along with the lapse of operation time, and a set value during combustion adjustment can not be comprehensively suitable for new environmental conditions, so that the NOx emission exceeds the requirements of environmental protection regulations.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a gas turbine NOx discharges prediction system, gas turbine NOx discharges prediction system comprises five parts of gas turbine, exhaust-heat boiler, the current control system of power plant, controller and remote server, be connected through the pipeline between gas turbine and the exhaust-heat boiler, the current control system of power plant and controller control gas turbine and exhaust-heat boiler's operation and carry out remote service operation through remote server, gas turbine includes compressor, combustion chamber, turbine and generator, rigid connection between compressor, combustion chamber, turbine and the generator, ambient humidity sensor and ambient temperature sensor are installed to the air inlet of compressor, exhaust-heat boiler includes a plurality of heating surface and chimney, can also arrange ammonia injection grid, catalyst and ammonia injection flow control valve in exhaust-heat boiler's the flue, the current control system of power plant includes DCS and TCS, the DCS electricity is connected with the controller and is connected with the TCS electricity, remote server comprises treater and memory.

In a preferred embodiment of the present invention, one or more gas turbines and associated DCS/TCS systems are provided in the gas turbine NOx emission prediction system, and combustion adjustment data of a plurality of the same type gas turbines can be shared.

As a preferred embodiment of the invention, the ambient humidity sensor and the ambient temperature sensor are respectively provided with a plurality of groups and are uniformly arranged at the air inlet section and the fuel inlet section of the gas turbine.

As a preferred embodiment of the present invention, the controller may be one of a laptop computer, a tablet computer, a central storage and processing server, or a cloud server.

In a preferred embodiment of the present invention, the gas turbine combustion adjustment data includes at least a boundary condition of stable combustion, a flue gas temperature, a set value such as a valve position of a fuel or air control valve, and a combustion engine load, a load increase/decrease rate, a NOx emission value, an ambient temperature, humidity, and the like at the time of setting;

in a preferred embodiment of the present invention, the real-time values from the DCS/TCS system at least include real-time operation data such as exhaust gas temperature, fuel or air control valve opening, engine load, load increase and decrease rate, ambient temperature and humidity.

In a preferred embodiment of the present invention, the values from the sensor data include at least temperature and relative humidity, and the sensor is installed at the inlet of the compressor to detect the relative humidity and temperature of the intake air in real time, and in some embodiments, the ambient temperature and humidity data are from weather forecast in the local weather section.

As a preferred embodiment of the present invention, an ammonia injection system is driven based on the predicted gas turbine NOx emission values in some real-time instances.

As a preferred embodiment of the present invention, a tangible, non-transitory computer readable medium having stored thereon computer instructions which, when executed by a controller, cause the controller to perform the steps of:

the method comprises the following steps: receiving and storing at least one of performance data related to NOx emissions during combustion tuning of the gas turbine, sensor data from controller sensors disposed at air and fuel inlets of the gas turbine, operational data from the DCS relating to the gas turbine;

step two: predicting NOx emissions or trends under operating conditions using a gas turbine NOx emission model, said gas turbine NOx emission model comprised of gas turbine combustion tuning data; and performing one or more preventative actions based on the NOx emission value or trend, the computer instructions when executed by the controller causing the controller to search for an applicable NOx emission model within a central server or cloud server, wherein the one or more preventative actions include ammonia injection control, combustion adjustment instructions, NOx emission monitoring.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the method, the NOx emission value of the gas turbine is predicted based on an emission model formed by historical data related to NOx emission during combustion adjustment according to environmental conditions or weather forecast, preventive preparation is made or the emission value is monitored according to the emission prediction, and in addition, the NOx emission value can drive ammonia injection control of a denitration system, so that the purposes of NOx emission prediction and targeted treatment of the gas turbine are achieved.

2. The gas turbine NOx emission prediction system designed by the scheme has good prediction accuracy, is simple in structure, has good practical value, and is beneficial to calling corresponding energy conservation and emission reduction.

Drawings

FIG. 1 is a diagram of an embodiment of a gas turbine power plant NOx emission prediction system;

FIG. 2 is a flow chart of a method for predicting NOx emissions using a NOx emissions prediction model.

In the figure: 100. a gas turbine; 101. air; 102. a compressor; 103. a combustion chamber; 104. a fuel; 105. a turbine; 106: a generator; 200. a waste heat boiler; 201. a heated surface; 202. spraying an ammonia grid; 203. a catalyst; 204. a chimney; 205. an ammonia injection flow control valve; 300. a power plant control system; 301, DCS;302.TCS;400. a controller; 401. an ambient humidity sensor; 402. an ambient temperature sensor; 500. a remote server; 501. a processor; 502. a memory.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-2, the present invention provides a technical solution: fig. 1 is a diagram of a NOx emission prediction system for a gas turbine power plant, including a gas turbine 100, a waste heat boiler 200, a plant existing control system 300, a controller 400, and a remote server 500, where the gas turbine 100 includes a compressor 102, a combustor 103, a turbine 105, and a generator 106. The compressor 102, the turbine 105 and the generator 106 are rigidly connected together, the waste heat boiler 200 comprises a plurality of heating surfaces 201 and a chimney 204, and in some embodiments, an ammonia injection grid 202, a catalyst 203 and an ammonia injection flow control valve 205 are arranged in a flue of the waste heat boiler 200; the gas turbine 100 is connected to the waste heat boiler 200 by means of a pipeline, and at least one ambient humidity sensor 401 and one ambient temperature sensor 402 are provided at the inlet of the compressor 102 for measuring the inlet temperature 401 and the inlet relative humidity 402 of the compressor 102. The existing control system 300 of the power plant comprises a DCS301 and a TCS302, which function to control the operation of the gas power plant, to protect equipment, to a controller 400 provided for predicting NOx emissions, and to a remote server 500 for storing and processing combustion regulation data of a plurality of gas turbines.

In the operation process, air 101 is compressed by the compressor 102 and then enters the combustion chamber 103, and is mixed with fuel 104 in a proper ratio and then combusted, chemical energy of the fuel is converted into heat energy of combustion products, high-temperature gas enters the turbine 105 to drive the turbine 105 to rotate, the heat energy is converted into mechanical energy, then the turbine 105 drives the generator 106 to rotate and convert the mechanical energy into electric energy, the rotating turbine 105 simultaneously drives the compressor 106 to suck and pressurize the air 101, the gas doing work inside the turbine 105 enters the heat exchange surface 201 of the waste heat boiler 200 through a pipeline to complete heat recovery, and then the gas is discharged into the atmosphere through the chimney 204.

In some embodiments, for a gas turbine 100 with emissions not meeting regulatory requirements, the exhaust heat boiler 200 is configured with an ammonia injection grid 202, a catalyst 203, and an ammonia injection flow control valve 205 in the back pass. At this time, the gas, which has performed work inside the turbine 105, enters the exhaust heat boiler 200 through a pipeline to complete heat recovery, carries with it nitrogen oxide (NOx) gas generated during combustion, and when flowing through the flue of the exhaust heat boiler 200, it is mixed with ammonia gas injected by the ammonia injection grid 202, and is reduced to nitrogen and water under the action of the catalyst 203, and is discharged to the atmosphere through the chimney 204.

The control of the above process is realized by the existing control systems DCS301 and TCS302 of the gas turbine power plant, wherein the TCS302 is responsible for controlling the start and stop and normal operation of the gas turbine 100, and has the functions of combustion condition monitoring and online combustion adjustment, the periodic and seasonal combustion adjustment set values and the corresponding performance data of the gas turbine 100 can be stored in the TCS302, the DCS301 has the functions of plant-wide coordination control and protection, the TCS302 directly communicates with the DCS301, the information related to the operation of the gas turbine 100 is guided to the controller 400 through the DCS301, the controller 400 communicates with the TCS302 through the DCS301 system, and the signals from the controller 400 can be transmitted to the gas turbines TCS301 and DCS302 or other control components in the system.

In some embodiments, one of the functions of the DCS301 is based on the signal to control the opening of the denitration ammonia injection flow control valve 205 to provide the appropriate reductant.

The ambient humidity sensor 401, the ambient temperature sensor 402 may include communication circuitry that allows the

sensors

401, 402 to be electrically coupled to the controller 400 or the remote server 500 via a wireless (e.g., bluetooth low energy) or wired connection (e.g., ethernet).

In some embodiments, the remote server 500 may receive NOx emission-related combustion tuning data from multiple gas turbines 100 and enable sharing of combustion tuning data for the same model of gas turbine 100. In this way, the cloud-based system may act as a central repository for data relating to NOx emissions (e.g., set point, performance, environmental conditions, NOx emissions, etc.) for a plurality of gas turbines 100 and a central processing system, which central processing system 500 is in communication with controller 400.

FIG. 2 is a flow chart of a method for predicting NOx emissions using a NOx emissions prediction model. The controller 400 receives combustion adjustment data, real-time operational data, and real-time environmental data from the gas turbine 100. As discussed previously, the combustion adjustment data includes combustion adjustment settings, performance data, ambient conditions, NOx emissions data, etc., and the real-time operating data includes real-time load of the gas turbine 100, the ambient humidity sensor 401, the ambient temperature sensor 402, etc. The combustion tuning data may be transmitted while the gas turbine 100 is making combustion tuning or during a shutdown phase.

In certain embodiments, the combustion adjustment data received by the controller 400 may be transmitted to a remote server or cloud server 500 such that the remote server or cloud server 500 may receive the combustion adjustment data for different gas turbines 100 via multiple controllers 400. The combustion adjustment data may be stored on a memory 502 of the remote server or cloud server 500 and analyzed by the processor 501, retrieved by the controller 400 from the remote server or cloud server memory 502, or the like.

The real-time operational data, real-time environmental data may be incorporated into at least one algorithm, and the like. The steps may receive and retrieve combustion tuning data for the same model gas turbine from the steps and may predict emissions produced by the gas turbine 100.

The step is the output of the predicted emissions value of the step, which may be sent to an environmental monitoring department or delivered to. In certain embodiments, the data of the step is transmitted to the DCS as one of the control signals to the ammonia injection flow control valve 205.

The step determines whether the emissions of the gas turbine 100 exceed the regulations. If NOx emissions exceed the regulations of the regulations, combustion regulations must be implemented.

The step of issuing a combustion adjustment request may be to alert an operator of the gas turbine 100 that a combustion adjustment is required. In other embodiments of the invention, the emission values may be automatically sent to the TCS302 or other technical support systems, such as, but not limited to, technical support sent to the gas turbine 100 of the plant subscription.

In other embodiments, the input values in FIG. 2 may be weather forecast data for the site of the plant including: ambient temperature, humidity and combinations thereof and load prediction of ACG. As previously discussed, weather conditions and loads may affect the emission levels of the operating gas turbine 100, which may cause the emissions of the gas turbine 100 to exceed regulatory requirements; it is desirable for a user to predict the emission levels of the gas turbine 100 under upcoming climate conditions and load conditions in order to be timely prepared, such as to notify a technical support or OEM manufacturer to pre-schedule a combustion tuning schedule. By accepting weather forecasts from local meteorological departments including at least humidity, temperature and combinations thereof, and load trends, NOx emission values can be predicted by means of the steps in order to prepare countermeasures and solutions.

In other embodiments, as previously described, for certain gas turbines 100 that have not met regulatory requirements for emissions, the data from the steps is sent to the DCS as one of the control signals for the ammonia injection flow control valve 205. Although the output values in fig. 2 are calculated based on the NOx emission model, since the NOx emission model is constructed based on one or more data sets installed at the time of combustion adjustment of the differently ignited gas turbines 100, in order to predict the future variation tendency of the ammonia injection amount in advance, control and advance regulation are performed based on the future variation amount of the ammonia injection amount, and the closed loop stability and the disturbance rejection capability of the NOx removal system are improved.

The present invention predicts combustion NOx emission values or trends of the gas turbine 100 using a combustion NOx emission model of the gas turbine 100 based on the condition data and the combustion tuning data. Based on the prediction of the NOx emission value or trend, one or more preventative actions may be performed, such as combustion auto-tuning, combustion tuning prediction scheduling combustion tuning, denitration ammonia injection control, remote monitoring of the emissions of the gas turbine 100, and the like.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A gas turbine NOx emission prediction system characterized by: the system for predicting the NOx emission of the gas turbine consists of five parts, namely a gas turbine (100), a waste heat boiler (200), an existing control system (300) of a power plant, a controller (400) and a remote server (500), wherein the gas turbine (100) and the waste heat boiler (200) are connected through a pipeline, the existing control system (300) of the power plant and the controller (400) control the operation of the gas turbine (100) and the waste heat boiler (200) and carry out remote service operation through the remote server (500), the gas turbine (100) comprises a gas compressor (102), a combustion chamber (103), a turbine (105) and a generator (106), the gas compressor (102), the combustion chamber (103), the turbine (105) and the generator (106) are in rigid connection, an ambient humidity sensor (401) and an ambient temperature sensor (402) are installed at the gas inlet of the gas compressor (102), the waste heat boiler (200) comprises a plurality of heating surfaces (201) and a chimney (204), an ammonia injection grid (202), a catalyst (203) and an ammonia injection valve (205) are further arranged in a flue of the waste heat boiler (200), the existing control system (300) comprises a TCS 302) and a TCS (302) and a remote server (302) which are electrically connected with the TCS control system (302), the remote server (500) is composed of a processor (501) and a memory (502), the gas turbine (100) and a matched DCS (301)/TCS (302) system arranged in the gas turbine NOx emission prediction system are provided with one or more than two, the combustion adjustment data of a plurality of gas turbines (100) of the same model can be shared, the ambient humidity sensor (401) and the ambient temperature sensor (402) are respectively provided with a plurality of groups and are uniformly arranged at an air inlet section and a fuel inlet section of the gas turbine (100), the controller (400) can be one of a laptop computer, a tablet computer, a central server or a cloud server, the combustion adjustment data of the gas turbine (100) at least comprises boundary conditions of stable combustion, exhaust gas temperature, valve position set values of a fuel or air control valve and gas turbine load, load lifting rate, NOx emission value, ambient temperature and humidity when set, the DCS (301)/TCS (302) system real-time numerical values comprise exhaust gas temperature, fuel or air control valve opening degree, gas turbine load, load lifting rate, ambient temperature and humidity operation data, real-time air humidity operation data, ambient temperature and humidity operation data, the DCS (301)/TCS (302) system real-time temperature and ambient humidity sensor are installed from the ambient temperature sensor (401) and ambient humidity sensor, the ambient temperature sensor (401) and ambient temperature sensor (401, the ambient temperature sensor are installed in real-time forecast of the ambient temperature sensor and ambient temperature sensor (401) of the ambient temperature sensor and ambient temperature sensor (401, the ambient temperature sensor (402) of the ambient temperature sensor and ambient temperature sensor (401, the ambient temperature sensor and ambient temperature sensor (401) of the ambient temperature sensor and ambient temperature sensor (402) of the gas inlet section of the gas turbine (401, the gas turbine (401) of the gas inlet section of the gas turbine (401) of the gas turbine (402), an ammonia injection system is driven based on the predicted gas turbine NOx emission value.

2. The prediction method of a gas turbine NOx emission prediction system of claim 1, characterized by: a tangible, non-transitory, computer-readable medium having stored thereon computer instructions that, when executed by a controller (400), cause the controller (400) to:

the method comprises the following steps: receiving and storing at least one of performance data related to NOx emissions during combustion tuning of the gas turbine, sensor data from ambient humidity sensors (401) and ambient temperature sensors (402) disposed at air and fuel inlets of the gas turbine (100), operational data associated with the gas turbine (100) from the DCS;

step two: predicting NOx emissions or trends under operating conditions using a gas turbine NOx emission model comprised of gas turbine (100) combustion adjustment data and performing one or more preventative actions based on the NOx emission values or trends, the computer instructions when executed by the controller (400) causing the controller (400) to search for an applicable NOx emission model within a central server or cloud server, wherein the one or more preventative actions include ammonia injection control, combustion adjustment instructions, NOx emission monitoring.