JPS5923923Y2 - Exhaust gas circulation type burner for reducing nitrogen oxide generation - Google Patents

Description

[Detailed explanation of the invention] This invention burns a large volume of low-pressure supplied fuel gas while also burning nitrogen oxides (nitrogen oxides), an air pollutant whose emissions have been subject to strict regulations in modern times. A burner that is capable of reducing the amount of NOx (hereinafter referred to as NOx) emitted; A primary combustion air jetting mechanism for flame stabilization is provided on the outer periphery of the primary combustion air jetting mechanism, and secondary combustion air is jetted to the outer periphery of the primary combustion air jetting mechanism, and the pressure is used to blow out the combustion exhaust gas. A secondary air nozzle for suction and circulation is provided, and at the tip of the venturi mechanism, the secondary combustion air ejected by the secondary air nozzle is sucked and circulated. The present invention relates to an exhaust gas circulation type nitrogen oxide generation reduction burner, which is provided with a mechanism for ejecting fuel gas from the venturi mechanism in a divergent manner at an appropriate inclination angle with respect to the burner axis so as to cross the burner.

As shown in FIG. 1, a conventional burner of this type with such a preemption mechanism is designed so that a large volume of fuel gas ejected from the tip of the central venturi mechanism 1 is appropriately spread out and ejected at an inclination angle of α°. Because it is structured as The fuel gas jetted out intersects with the primary combustion air jetted out parallel to the burner axis a from the jetting mechanism 2 on its outer periphery, and the large volume of fuel gas is spread at the inclination angle α°. The momentum in the direction of the force is obstructed.

Therefore, the velocity due to the momentum of the fuel gas being inhibited with respect to the mixture of the secondary combustion air ejected from the secondary air nozzle 3A and the combustion exhaust gas sucked by the ejection. Due to the combination of the delay in mixing due to the drop in the amount of air and the reduction in forced mixing force due to the drop in momentum, early and reliable mixing of the fuel gas, secondary air and exhaust gas becomes impossible. As a result, the effect of reducing NOx due to the contribution of circulating exhaust gas to combustion has become insufficient.

In other words, the timing of mixing the fuel gas and the combustion exhaust gas sucked and circulated by the secondary air is delayed, and the mixing power is weak, so the fuel gas is combusted without sufficient mixing of the secondary air and exhaust gas. As a result, even though an exhaust gas circulation system was adopted, the desired NOx reduction effect could not be fully achieved.

The present invention has been made in view of the above circumstances, and its purpose is to achieve the above-mentioned advantages in the above-mentioned burner by diffusing and ejecting a large volume of fuel gas radially at an appropriate inclination angle with respect to the burner axis. By improving the engine so that its ejection momentum is not inhibited by the primary combustion air while maintaining a sufficient amount of air, the desired NOx reduction effect achieved by adopting the exhaust gas circulation system can be more than fully achieved. The purpose is to realize the improvement with the simplest possible configuration.

In order to achieve the above object, the thrust-based circulation type nitrogen oxide generation reduction burner according to the present invention has a structure in which, in the above-mentioned one, the tip of the secondary combustion air injection mechanism is provided with a The present invention is characterized in that a mechanism is provided for ejecting the primary combustion air at an angle of divergence that is equal to or approximately equal to an angle of ejection inclination of the fuel force.

According to the characteristic configuration described above, although the extremely simple and economical improvement of providing a mechanism for ejecting primary air for combustion radially, the state in which a large amount of fuel gas is spread out in a radial manner is maintained. Moreover, since the primary combustion air is ejected parallel to the periphery of this fuel gas jet, it is possible to obtain the NOx reduction effect by performing low-temperature charcoal burning in a state where the fuel density is small, and also to reduce the amount of NOx between the primary combustion air and the fuel. Since the gas ejection directions are parallel to each other and do not intersect as in the conventional case, the ejection momentum of the fuel gas is not inhibited by the ejection of the primary air for combustion.
Therefore, it is possible to increase both the mixing speed and mixing force of the fuel gas with respect to the secondary combustion air ejected from the air nozzle and the combustion exhaust gas sucked and circulated thereby, and the secondary combustion air is This allows combustion to take place, thereby making it possible to maximize the desired NOx reduction effect of the exhaust gas circulation system.

Hereinafter, an embodiment of the present invention will be described based on FIG. 2.

Reference numeral 1 denotes a venturi mechanism that sucks low-pressure supplied fuel gas using air jet pressure, and is installed on the burner axis a, and its tip has a venturi mechanism that spreads the fuel gas appropriately with respect to the burner axis a. As a mechanism 4 for ejecting water at an inclination angle α°, a cone member is arranged in series at a location facing the opening at the tip of the Venturi tube 1A.

Reference numeral 2 denotes a primary combustion air injection mechanism 2 for flame stabilization disposed on the outer circumferential side of the venturi mechanism 1, and a tip of the mechanism 2 is provided with a primary combustion air injection mechanism 2 for directing the primary air in the direction of the burner axis a. The divergent inclination angle β is equal to or approximately equal to the ejection inclination angle α° of the fuel gas.

A large number of air ejection holes 5 are used as the mechanism 5 for ejecting the air.
This is a ring-shaped baffle plate with a shape fixed in an inclined position.

In the figure, IB is the air nozzle of the bench 1 mechanism 1, 3 is the exhaust gas circulation mechanism provided on the outer circumferential side of the secondary combustion air injection mechanism 2, 3A... A secondary air nozzle in the exhaust gas circulation mechanism 3,
The combustion exhaust gas is sucked and circulated using the ejection pressure of the secondary combustion air from these secondary air nozzles 3A.

Further, 6 is an ignition mechanism.

[Brief explanation of the drawing]

The drawings illustrate an embodiment of the thrust-based circulation type burner for reducing the amount of nitrogen oxide generated according to the present invention, and FIG. 1 is a longitudinal sectional side view of a conventional burner, and FIG. 2 is a longitudinal sectional side view of the burner of the present invention. . DESCRIPTION OF SYMBOLS 1...Venturi mechanism, 2...Primary combustion air injection mechanism, 3A...Secondary air nozzle, 4...Fuel gas inclined injection mechanism, 5.・・・・・・
・Air tilt jetting mechanism for primary combustion.

Claims (1)

[Scope of utility model registration request] A venturi mechanism 1 that sucks low-pressure supplied fuel gas using air jet pressure is provided on the burner axis a, and an air jet mechanism 2 for primary combustion for flame stabilization is provided on the outer peripheral side of the venturi mechanism 1. A secondary air nozzle 3A is provided on the middle circumferential side of the combustion air injection mechanism 2, which blows out secondary combustion air and sucks and circulates combustion exhaust gas using the pressure of the secondary combustion air.
..., and the venturi mechanism 1
At the tip of the secondary air nozzle 3A, in order to cross the fuel gas with the mixture of the combustion exhaust gas sucked and circulated by the secondary heating air ejected by the secondary air nozzle 3A, In the exhaust gas circulation type nitrogen oxide generation reduction burner, which is provided with a mechanism 4 for ejecting the fuel gas from the venturi mechanism 1 in a divergent shape at an appropriate inclination angle α° with respect to the burner axis a, A mechanism 5 is provided at the tip of the combustion air injection mechanism 2 for ejecting the primary combustion air with respect to the burner axis a at an angle of divergence β° that is equal to or approximately equal to the ejection inclination angle α° of the fuel gas. An exhaust gas circulation type burner for reducing the amount of nitrogen oxide generated, characterized by the following: