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CN-121993794-A - Ultralow NOx combustor

CN121993794ACN 121993794 ACN121993794 ACN 121993794ACN-121993794-A

Abstract

The invention relates to an ultralow NOx burner which comprises peripheral guns, a central ring gun, a pilot burner, an air box, a brick supporting plate, an inner layer brick and an outer layer brick, wherein a plurality of peripheral guns are uniformly distributed on the inner wall of a burner shell, the pilot burner is arranged in the center of the inner cavity of the shell, the central ring gun is arranged around the pilot burner, the brick supporting plate is arranged above the burner shell, the inner layer brick and the outer layer brick are arranged on the brick supporting plate, a hollow cavity formed inside the inner layer brick forms a primary air channel, a cavity between the inner layer brick and the outer layer brick is a secondary air channel, the upper part of the outer layer brick is closed, and the air box is arranged on the burner shell and is communicated with the inner cavity of the shell. The invention breaks through the limitation of single classification of the traditional burner, and realizes the accurate control of the classification proportion and the combustion height of the gas and air cooperative classification through the two-layer spray gun and the two-layer burner block structure.

Inventors

  • LI ZIYAO
  • YU WEIGEN
  • LI YIFENG
  • YAN YUPING
  • LI ZHONGYI
  • HAN XUEBIN

Assignees

  • 北京航天石化技术装备工程有限公司

Dates

Publication Date
20260508
Application Date
20251209

Claims (7)

  1. 1. An ultralow NOx burner is characterized by comprising a peripheral gun (1), a central ring gun (2), a pilot burner (3), an air box (4), a brick supporting plate (5), an inner layer brick (6) and an outer layer brick (7); The burner comprises a burner shell, a plurality of peripheral guns (1), a brick supporting plate (5), an inner layer brick (6) and an outer layer brick (7), wherein the inner wall of the burner shell is uniformly distributed with a plurality of peripheral guns (1), a pilot lamp (3) is arranged in the center of the inner cavity of the shell, a central ring gun (2) surrounds the pilot lamp (3), the peripheral guns (1), the central ring gun (2) and the bottom of the pilot lamp (3) are all penetrated out of the lower end of the burner shell, a brick supporting plate (5) is arranged above the burner shell, a hollow cavity formed by the inner side of the inner layer brick (6) forms a primary air channel (101), a cavity between the inner layer brick (6) and the outer layer brick (7) is a secondary air channel (102), and the upper parts of the central ring gun (2) and the pilot lamp (3) extend into the hollow cavity of the inner layer brick, and the primary air channel (101) and the secondary air channel (102) are communicated with the inner cavity of the burner shell; The upper part of the peripheral gun is provided with an upward main spray hole and a horizontal spray hole, the horizontal spray hole faces the outer layer brick, a preset hole is arranged on the outer layer brick at the position corresponding to the horizontal spray hole, the central ring gun is provided with a right upper spray hole and an oblique upper spray hole, and the oblique upper spray hole faces the inner wall of the inner layer brick.
  2. 2. The ultra-low NOx burner of claim 1, wherein the acute angle between the center of the upper main nozzle hole above the peripheral gun and the vertical is 5-12 °.
  3. 3. An ultra-low NOx burner according to claim 1, wherein the primary air duct lower surface area is 15% -25% of the primary air duct and secondary air duct lower surface area.
  4. 4. The ultra-low NOx burner of claim 1, wherein a distance is provided between the outside of the inner layer brick and the inside of the outer layer brick.
  5. 5. An ultra-low NOx burner according to claim 4, wherein the minimum horizontal distance between the outside of the inner layer brick and the inside of the outer layer brick 10Mm-40mm.
  6. 6. The ultra-low NOx burner of claim 1, wherein the center ring gun load is 10-15% of the total burner load.
  7. 7. An ultra-low NOx burner according to claim 1, wherein the burner air-fuel ratio is achieved by controlling the ratio of the central annular cavity to the fuel intake at the bottom of the peripheral guns and the minimum annular space area between the inner and outer bricks 。

Description

Ultralow NOx combustor Technical Field The invention belongs to the technical field of industrial combustion equipment, relates to an ultralow NOx burner, and in particular relates to an ultralow NOx burner of a heating furnace with gas and air in cooperative grading. Background The main technology of low-nitrogen combustion of the existing heating furnace burner is gas staged combustion or air staged combustion, and the existing burner is matched with the flue gas circulation technology mostly provided with, so that only 60 mg/Nm 3 can be ensured, 50 mg/Nm 3 is strived for, and the construction cost and the continuous catalyst investment of a follow-up denitration device are increased for the emission standard with higher requirements. The cooperation of the gas classification and air classification technology is difficult to design, particularly the classification proportion and the combustion height of the gas and the air need to be precisely controlled, and the primary combustion area and the secondary combustion area cannot be coupled, so that the peak temperature of the flame is increased to the threshold value for quickly generating thermal NOx. To solve the above contradiction, there is a need in the art to develop a gas and air staged low NOx combustion system. Disclosure of Invention The invention solves the technical problems of overcoming the defects of the prior art and providing an ultralow NOx burner. The solution of the invention is as follows: an ultralow NOx burner comprises a peripheral gun, a central ring gun, a pilot lamp, an air box, a brick supporting plate, an inner brick and an outer brick; The inner wall of the burner shell is uniformly provided with a plurality of peripheral guns, a pilot burner is arranged in the center of the inner cavity of the shell, the central ring gun is arranged around the pilot burner, the bottoms of the peripheral guns, the central ring gun and the pilot burner all penetrate out of the lower end of the burner shell, a brick supporting plate is arranged above the burner shell, an inner layer brick and an outer layer brick are arranged on the brick supporting plate, a hollow cavity formed by the inner side of the inner layer brick forms a primary air channel, a cavity between the inner layer brick and the outer layer brick is a secondary air channel, the upper parts of the central ring gun and the pilot burner extend into the hollow cavity of the inner layer brick, and the primary air channel and the secondary air channel are communicated with the inner cavity of the burner shell; The upper part of the peripheral gun is provided with an upward main spray hole and a horizontal spray hole, the horizontal spray hole faces the outer layer brick, a preset hole is arranged on the outer layer brick at the position corresponding to the horizontal spray hole, the central ring gun is provided with a right upper spray hole and an oblique upper spray hole, and the oblique upper spray hole faces the inner wall of the inner layer brick. Preferably, the acute included angle between the center of the upper main spray hole above the peripheral gun and the vertical direction is 5-12 degrees. Preferably, the lower surface area of the primary air channel accounts for 15% -25% of the sum of the lower surface areas of the primary air channel and the secondary air channel. Preferably, a distance is reserved between the outer side of the inner layer brick and the inner side of the outer layer brick. Preferably, the minimum horizontal distance between the outside of the inner layer brick and the inside of the outer layer brick10Mm-40mm. Preferably, the load of the center ring gun accounts for 10-15% of the total load of the burner. Preferably, the burner air-fuel ratio is achieved by controlling the ratio of the central annular cavity to the fuel intake at the bottom of the peripheral gun, and the minimum annular space area between the inner and outer bricks。 Compared with the prior art, the invention has the beneficial effects that: 1. The ultralow NOx emission is that the primary combustion zone burns lean in the burner block and rich in oxygen, so that the combustion deviates from the stoichiometric ratio, the combustion temperature is less than or equal to 1500 ℃, and the secondary combustion zone burns under dilution of incombustible components in the hearth, so that the local high temperature of flame is reduced, the combustion temperature is less than or equal to 1300 ℃, and the thermal NOx generation is inhibited. In the injection area of the peripheral gun nozzle, the gas injects inert gas in the hearth, so that the local oxygen content is low, and the local high temperature is reduced, thereby reducing the generation of nitrogen oxides. 2. The burner block structure is succinct effective, through the structural variation of two-layer burner block, adapts to the flame height of different fuels of different loads, guarantees that two-layer combustion zone can't interfere t