CN216716208U

CN216716208U - System for realizing low-nitrogen combustion emission of combustor

Info

Publication number: CN216716208U
Application number: CN202123091271.7U
Authority: CN
Inventors: 于利进; 严鹰; 陆永生
Original assignee: Shanghai Boiler Works Co Ltd
Current assignee: Shanghai Boiler Works Co Ltd
Priority date: 2021-12-09
Filing date: 2021-12-09
Publication date: 2022-06-10
Anticipated expiration: 2031-12-09

Abstract

The utility model provides a system for realizing low-nitrogen combustion emission of a burner, which relates to the technical field of flue gas recirculation and low-nitrogen emission, and comprises the burner, an angle sensor, a controller, an electric air valve and a flue gas circulation pipeline, wherein after the burner is ignited to work, the system is automatically started, the angle sensor transmits a burner air valve opening signal to the controller, the controller controls the opening of the electric air valve according to the air valve opening, the flue gas circulation flow is controlled, the generation of nitrogen oxides in the combustion process is further inhibited, the burner is enabled to be stably combusted, and the emission of waste gas reaches the standard; the burner is improved, the burner does not need to be replaced, the original control system is not changed, the burner is stable in combustion, and the emission reaches the standard; the construction period is short, the cost is reduced by 80% compared with the low-nitrogen modification scheme for replacing the combustor, and the method is suitable for low-nitrogen modification of the built boiler.

Description

System for realizing low-nitrogen combustion emission of combustor

Technical Field

The utility model belongs to the technical field of flue gas recirculation and low nitrogen, and particularly relates to a system for realizing low nitrogen combustion emission of a combustor.

Background

At present, the low-nitrogen combustion technology mainly comprises: air staging methods, low-nitrogen burners, flue gas recirculation techniques, reburning techniques, and the integrated utilization of multiple technologies.

The air classification method has the worst emission reduction effect, can reduce the generation of nitrogen oxides by 35 to 50 percent, and has substandard emission; the low-nitrogen combustion method combining the low-nitrogen combustor and the flue gas recirculation technology has the best emission reduction effect, can reduce 50% -90% of nitrogen oxides, but the low-nitrogen combustor is complex in structure and expensive in price.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the problems that: the burner does not need to be replaced, and the flue gas recirculation low-nitrogen technology is utilized under the condition that the original control system is not changed, so that the burner is stable in combustion, and the emission reaches the standard.

In order to solve the problems, the utility model provides a system for realizing low-nitrogen combustion emission of a combustor, which comprises the combustor, an angle sensor, a controller, an electric air valve and a flue gas circulating pipeline, wherein the flue gas circulating pipeline is communicated into the combustor from a flue, the electric air valve is installed on the flue gas circulating pipeline, the angle sensor is connected with an air door valve rod in the combustor, and the controller is connected with the angle sensor and the electric air valve.

Further, the controller is a PLC controller.

Furthermore, the angle sensor is connected with a flexible coupling for coaxiality of an air door valve rod in the combustor, and an opening degree signal of the air door of the combustor is transmitted to the PLC.

The combustor needs gas and air when burning, and the air passes through the fan and draws in the combustor from the air door, and the air door aperture size difference represents the intake difference, represents the combustor power difference.

The angle sensor is an element for converting angle change into an electric signal, and because the angle sensor is connected with the air door valve rod, the opening degree of the air door is increased, the angle sensor can rotate by the same angle and convert the angle signal into the electric signal.

In addition, because the angle sensor is sensitive to vibration during working, and the combustor can vibrate during working, the angle sensor is connected with the air door valve rod in the combustor through the flexible coupling for coaxiality, so that the influence of the combustor vibration on the angle sensor can be reduced, and the numerical value distortion is avoided.

Further, the flue gas circulation pipeline is communicated into the combustor from a flue behind the heat exchanger.

Further, the heat exchanger is an economizer or a preheater.

The economizer or preheater is used for reducing the temperature of exhaust gas and increasing the temperature of inlet water, circular flue gas is introduced from the rear end of the economizer or preheater, the temperature of the flue gas is low, the heat insulation thickness of a flue gas circulation pipeline, the service life of an electric air valve and the service life of a combustor fan are positively influenced, and particularly the temperature of flame of the combustor is positively influenced.

According to the utility model, the flue gas in the flue is introduced into the combustor through the flue gas circulation pipeline by utilizing a flue gas recirculation technology, so that the oxygen content in combustion-supporting air is reduced, the flame temperature during combustion is further reduced, the flame temperature is low, NOx is less, and the low-nitrogen emission of the combustor is realized; wherein, the circulation volume of flue gas needs to change according to combustor power change, otherwise the burning is unstable, easily leads to flame-out, and the electronic blast gate aperture of difference corresponds different air door aperture, can obtain the fitting curve between air door aperture and the electronic blast gate aperture through the debugging calculation, obtains combustor power through the air door aperture, controls the flue gas circulation volume through controlling electronic blast gate aperture, makes it match combustor power.

Has the beneficial effects that:

(1) the utility model provides a system for realizing low-nitrogen combustion emission of a combustor, which is automatically started after the combustor is ignited to work, partial smoke is extracted from a flue by utilizing an original combustor fan and mixed with air to participate in combustion, an opening signal of a combustor air door is transmitted to a controller by an angle sensor, the controller controls the opening of an electric air valve according to the opening of the air door, the circulation flow of the smoke is controlled, the generation of nitrogen oxides in the combustion process is further inhibited, the combustion of the combustor is stable, and the emission waste gas reaches the standard.

(2) According to the utility model, the burner is improved, the burner does not need to be replaced, the original control system is not changed, the burner is stable to burn, and the emission reaches the standard; the construction period is short, the cost is reduced by 80% compared with the low-nitrogen modification scheme for replacing the burner, and the method is suitable for low-nitrogen modification of the built boiler; simple structure, reliability and small occupied area.

The conception, the specific structure and the technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, the features and the effects of the present invention.

Drawings

FIG. 1 is a schematic block diagram of a system for achieving low NOx combustion emissions from a combustor;

reference numerals:

1. an angle sensor; 2. a controller; 3. a flue gas circulation duct; 4. an electric air valve; 5. a burner; 6. a flue.

Detailed Description

The utility model will be further illustrated with reference to specific embodiments. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention can be made by those skilled in the art after reading the teaching of the present invention, and these equivalents also fall within the scope of the claims appended to the present application.

In the drawings, structurally identical elements are represented by like reference numerals, and structurally or functionally similar elements are represented by like reference numerals throughout the several views. The size and thickness of each component shown in the drawings are arbitrarily illustrated, and the present invention is not limited to the size and thickness of each component. The thickness of the components may be exaggerated where appropriate in the figures to improve clarity.

Example (b):

as shown in fig. 1, in a preferred embodiment, taking a gas burner as an example, the utility model provides a system for realizing low-nitrogen combustion emission of the burner, which comprises the gas burner, an angle sensor 1, a PLC controller, an electric air valve 4 and a flue gas circulation pipeline 3, wherein the flue gas circulation pipeline 3 is communicated to the gas burner from a flue 6 behind the economizer, a hole is formed in a shell of the gas burner, the flue gas circulation pipeline 3 extends into the center of a fan inside the shell, the electric air valve 4 is installed on the flue gas circulation pipeline 3, a controller 2 is connected with the angle sensor 1 and the electric air valve 4, the angle sensor 1 is coaxially connected with an air door valve rod in the gas burner by a flexible coupling, and an opening signal of the air door of the burner is transmitted to the PLC controller.

When the burner 5 is ignited to work, the system is automatically started, when the system works, the angle sensor 1 transmits an opening degree signal of an air door of the burner 5 to the PLC, the PLC controls the opening degree of the electric air valve 4 through a fitting curve between the opening degree of the air door and the opening degree of the electric air valve 4, and controls the circulating flow of flue gas, so that the generation of nitrogen oxides in the combustion process is inhibited, the burner 5 is stable in combustion, and the emission of waste gas reaches the standard; when the burner 5 is shut down or stops working, the electric air valve 4 is closed, and the system stops working.

Claims

1. The utility model provides a system for realize low nitrogen burning of combustor and discharge which characterized in that, includes combustor (5), angle sensor (1), controller (2), electronic blast gate (4) and flue gas circulating line (3), flue gas circulating line (3) communicate to in combustor (5) from flue (6), install electronic blast gate (4) on flue gas circulating line (3), angle sensor (1) with air door valve rod in combustor (5) is connected, controller (2) with angle sensor (1) with electronic blast gate (4) are connected.

2. The system for realizing low-NOx combustion emissions of a burner as claimed in claim 1, wherein said controller (2) is a PLC controller.

3. The system for realizing low-nitrogen combustion emission of the burner as claimed in claim 2, wherein the angle sensor (1) is coaxially connected with a flexible coupling for a damper valve rod in the burner (5) and transmits a damper opening signal of the burner (5) to a PLC controller.

4. A system for realizing low-nitrogen combustion emission of a burner as defined in any one of claims 1 to 3, characterized in that the flue gas circulation duct (3) communicates from a flue (6) after a heat exchanger to the inside of the burner (5).

5. The system for achieving low NOx combustion emissions of a combustor as claimed in claim 4, wherein said heat exchanger is an economizer or a preheater.