KR200177803Y1 - Low nox burner by changing the shape of flow divider - Google Patents

Abstract

1. TECHNICAL FIELD OF THE INVENTION

The present invention relates to a nitrogen oxide (NOx) reduction burner by changing the shape of the flu divider.

2. The technical problem the invention is trying to solve

Compared with the exhaust gas circulation method and the two-stage combustion method in the furnace, it is more economical in equipment, maintenance, and maintenance, and it is intended to create a burner that can reduce nitrogen oxides without additional equipment by only changing the structure by considering aerodynamics inside the burner.

3. Summary of solution of design

It is solved by the present invention in which a bidirectional air dispersion plate 3 is attached to the end of the flow divider 4 of the low nitrogen oxide burner.

4. Important uses of the devise

It can reduce nitrogen oxide and dust generated by the existing burner by more than 30% and prevent local overheating of the furnace water pipe to maintain the overall temperature distribution in the furnace and apply it to various furnace shapes with improved combustion reliability.

Description

NOx-reducing burner by changing the shape of the flu divider

The present invention relates to a nitrogen oxide (NOx) reduction burner by changing the shape of the flu divider, and more particularly to an industrial burner that can reduce the nitrogen oxide, a pollutant generated by the combustion of fossil fuels during the combustion process, Air divider is installed at both ends of the flow divider and diffused radially in the primary air roll passing through the outer vane without increasing the turning to create a surplus of air in the wake of the flame. By promoting the reduction reaction of the produced nitrogen oxides and the complete combustion of incomplete combustion materials, the secondary air and the tertiary air passing through the inner vane to enhance the axial velocity component to promote the backward flow of fuel It is located in the flame zone at low temperature to promote the gasification of nitrogen-based gas in the fuel so as to suppress the production of partial fuel nitrogen oxide (FUEL NOx). Through this, the reduction of unburned gas and dust, which are pollutants, and the stabilization of the initial combustion zone initializing salt, and the high temperature zone by maximizing the quenching effect of the high temperature flame surface and increasing the time delay of combustion in the furnace. This is to reduce the production of nitrogen oxides.

In industrial boilers using fossil fuels, nitrogen oxides formed during the combustion process are the main cause of photochemical smog, and their emissions are strictly regulated. Therefore, in the conversion of chemical energy into thermal energy by combustion, complete combustion is a basic requirement of the burner, and the reduction of nitrogen oxide without increasing the amount of fine dust is a very important item that determines the performance of the burner.

The nitrogen oxide reduction technique used in the industrial burner is conventionally used in high temperature combustion zones to reduce the 'thermal NOx' generated by nitrogen contained in the combustion air reacting with excess oxygen in a high temperature combustion atmosphere. In order to suppress the reaction of nitrogen while maintaining fuel over-air insufficiency so that excess oxygen is insufficient, incomplete combustion products caused by lack of air are completely burned by injecting sufficient combustion air from the downstream side of the furnace where the furnace temperature is relatively low. The method is used in numbers. In other words, by forming a relatively low temperature combustion atmosphere at the front of the burner, supplying primary combustion air to suppress the production of nitrogen oxides to maintain the fuel surplus and lack of air, and to completely burn the produced combustion products Supply primary combustion air.

As such, companies and apparatus currently in use as a method for forming a fuel over-air shortage in front of a burner include an exhaust gas recirculation method, a two-stage combustion method in a furnace, and a low nitrogen oxide burner.

The exhaust gas recirculation method is a method of mixing a part of the burned exhaust gas with combustion air and introducing it into a burner, and the two-stage combustion method in the furnace sends a part of combustion air directly to a hole installed on the burner to burner area. This method is to completely burn the combustion gas which is incompletely burned in the air. The exhaust gas circulation method and the two-stage combustion method in the furnace are nitrogen oxide reduction method by the addition of equipment. The low nitrogen oxide burner is a burner that reduces the generation of nitrogen oxides by controlling the mixing characteristics of the combustion air and the fuel by using an aerodynamic method of splitly supplying combustion air from the burner.

The former exhaust gas circulation method and the two-stage combustion method in the furnace have a high effect of reducing nitrogen oxides, but an additional burden is required for the economic burden, equipment, maintenance, and maintenance, since additional equipment for reducing nitrogen oxides must be installed in the existing equipment. do. Therefore, in recent years, it is a trend to prefer the latter low nitrogen oxide burner which can reduce the nitrogen oxide without additional equipment only by the structural change by the aerodynamic consideration inside the burner.

Invented to cope with such demands actively, the present invention prevents excessive increase in unburned water and dust generated during the combustion process by making the downstream combustion region in excess air due to the aerodynamic consideration of the burner. Stabilization and lean combustion are alleviated to alleviate the maximum temperature range of flames due to delayed combustion reaction, thereby forming a low temperature combustion atmosphere, thereby suppressing the formation of nitrogen oxides in the excess fuel region near the burner and forming an excess air region in the wake of the flame. Therefore, it is an object of the present invention to provide a low nitrogen oxide burner that reduces nitrogen oxides by promoting a reduction reaction of nitrogen oxides to nitrogen.

The purpose is to stabilize the initial salts by the diffusion effect of the primary air, which is strongly swirled without changing the degree of rotation, by arranging the bidirectional air dispersion plate at the end of the flu divider at an appropriate angle. It suppresses the formation of nitrogen oxides by reducing the high-temperature area due to the excess fuel and cooling the high-temperature flame surface by making the air ratio <1), and strengthens the axial velocity component by weakly turning air to promote the backward movement of the fuel By placing it in the flame zone, it promotes the gasification of the nitrogenous component of the fuel tank, thereby suppressing partial 'FUEL NOx' formation, and the incomplete combustion material generated by the fuel surplus is concentrated in the circulating air outside the flame zone. And intensive oxidation in weak-turn air and the downstream combustion zone to ensure complete combustion, and by making the downstream combustion zone into excess air, It can be achieved by the present invention to promote the reduction of water to nitrogen, will be described in detail below with reference to the accompanying drawings.

1 is an enlarged cross-sectional view of the present invention and a bidirectional air dispersion plate.

2 is a distribution diagram of the combustion air in the furnace of the present invention.

3 is a burner outlet velocity distribution characteristic diagram of the present invention.

4 is a temperature distribution characteristic diagram of the furnace of the present invention.

5 is a nitrogen oxide and dust emission characteristics of the present invention.

6 is a cross-sectional view of a conventional design.

* Explanation of symbols for main parts of the drawings

1: primary bain 2: secondary bain

3: two-way air dispersion plate 4: outer burner

5: flu divider 6: burner parallel part

7: fuel nozzle 8: diffusion type diffuser

9: primary vane drive shaft 10: secondary vane drive shaft

1 is a sectional view of the present invention and an enlarged view (a) of a bidirectional air dispersion plate.

The present invention is designed to burn the nitrogen oxide in the burner itself without increasing the amount of special unburned substances and dust, the primary vane (1), secondary vanes (2), burner barrel (4), flu divider (5), In the low nitrogen oxide burner burned by the burner parallel part 6, the fuel nozzle 7, the diffusion type injector 8, the primary vane drive shaft 9, and the secondary vane drive shaft 10, the flu divider 5 is used. It consists of a two-way air distribution plate (3) attached to the end.

The air dispersion plate 3 has the outer refraction portion 3 'bent to the outside of the flu divider 5 by α angle with respect to the horizontal axis B of the flu divider 5, and the inner refraction portion 3 " The inside of the flu divider 5 is flexed by a D angle.

Hereinafter, the operation of the present invention will be described in detail.

2 is a distribution diagram of the combustion air in the present invention, FIG. 3 is a burner outlet velocity distribution characteristic diagram of the present invention, FIG. 4 is a temperature distribution characteristic diagram of the furnace design, and FIG. 5 is a nitrogen oxide and Dust emission characteristics are shown.

The burner to which the present invention is applied has a diffusion effect by reinforcing radial velocity components to some air passing through the primary vane 1 for turning as shown in FIG. 1 by attaching a bidirectional air dispersion plate to the end of the flu divider of the conventional burner of FIG. Increase and increase the axial velocity component in weakly turned secondary and tertiary air and enter the furnace.

The flu divider (5) extends to the burner parallel part (6) and the fuel is sprayed symmetrically in the center of the furnace through a fuel nozzle (7) installed in the center of the burner, wherein the combustion air secondary vane (2) The axial flow rate component is strengthened and the weakly slewing air supplied crosswise with the slewing air pushes the evaporating fuel droplets to the downstream side and is located in the unburned state by placing the fuel droplets in the low temperature flame zone. Nitrogen content in the fuel is gasified and fuel nitrogen oxides can be suppressed, thereby acting particularly effectively on the combustion of the nitrogen-rich fuel.

In addition, the combustion air rotated while passing through the primary turning vane 1 is concentrated by the fluid divider 5 and the bidirectional air distribution plate 3 toward the outside of the furnace rather than the center of the furnace, as shown in FIG. Flame stabilization in the combustion zone is achieved, and cooling of the flame is promoted to reduce the combustion zone at high temperature to suppress the production of nitrogen oxides.

In this process, the flame zone becomes a fuel overcapacity with insufficient combustion air, thereby suppressing the generation of secondary nitrogen oxides, and the main combustion occurs while the steel turning air and the weak turning air passing through the bidirectional air distribution plate 3 cross each other. By maximizing the flame cooling effect in the area, the overall temperature distribution of the furnace is equalized to the fourth degree, thereby suppressing the generation of thermal nitrogen oxides.

In addition, as shown in FIG. 3, the turning direction is enhanced by the bidirectional air dispersing pipe 3 to increase the radial velocity component, so that the residence time of the combustion gas is relatively long, thereby making it sufficient time to achieve complete combustion in the downstream. As a result, the reduction zone of the intermediate product generated by the fuel surplus and the generated nitrogen oxide to nitrogen also becomes long, thereby maximizing the nitrogen oxide reduction effect.

And as shown in Fig. 3, the bidirectional air dispersion plate increases the degree of mixing in the flame wake by the diffusion of the combustion air passing through it, thereby creating sufficient conditions to achieve complete combustion in the wake. Nitrogen oxides can be reduced by increasing the atmosphere of the reduction reaction with the generated nitrogen oxides to nitrogen.

As an effect of this invention, it showed in FIG. 4 and FIG. 5 compared with the conventional design. As shown in the above results, it is possible to reduce nitrogen oxide and dust generated by the existing burner by more than 30%, and to prevent the local heat overheating of the furnace water pipe by considering the length of the flame to uniformly distribute the overall temperature distribution in the furnace. It is possible to achieve the optimum combustion state. In addition, since the appropriate turning degree according to the furnace shape can be adjusted by the primary vane drive shaft 9 and the secondary vane drive shaft 10, it is possible to improve and apply combustion reliability to various furnace shapes.

In addition, compared with the conventional exhaust gas circulation method and the two-stage combustion method in the furnace, there is no need to install additional equipment for reducing nitrogen oxides in the existing equipment, and thus it is economical and has excellent effects of easy installation, maintenance, and maintenance.

Claims (1)

Primary vane (1), secondary vane (2), burner barrel (4), flow divider (5), burner runner (6), fuel nozzle (7), diffusion type flame sprayer (8), primary vane drive shaft (9) In the low nitrogen oxide burner composed of the secondary vane driving side 10, the outer refractive portion 3 ′ is deflected outwardly of the flu divider 5 with respect to the horizontal axis B of the flu divider 5. And a bidirectional air dispersion plate 3 having an inner refraction portion 3 &quot; refracted to the inside of the flu divider 5 by? Angle is attached to the end of the flu divider 5, so that nitrogen oxides are unpulverized. NOx-reduced burners by changing the shape of the flu divider without a special increase in