CN-121993795-A - Opposite-impact burner for high-efficiency removal of nitrogen oxides by ammonia-hydrogen combustion

Abstract

The invention belongs to the field of energy and combustion, and particularly relates to a hedging type combustor for efficiently removing nitrogen oxides by ammonia-hydrogen combustion. The utility model provides a hedging combustor, includes the combustor body, have main fuel injection port, secondary fuel injection port and gas vent in the combustor body, main fuel injection port with secondary fuel injection port sets up relatively, main fuel follow main fuel injection port gets into the combustor, secondary fuel gets into the combustor from secondary fuel injection port, two air current are carried and are formed the hedging flow field along opposite direction in the combustor. By the DeNOx process occurring in the side reaction zone, nitrogen oxides are reduced to nitrogen and water, and the final combustion products are discharged through the exhaust port. Compared with the conventional straight-through burner, the opposite-impact burner can obviously reduce the emission of nitrogen oxides and ensure that the leakage amount of ammonia is in an acceptable range, thereby effectively improving the overall performance of an ammonia-hydrogen combustion system.

Inventors

• CAI TAO
• MA XIAN
• TANG AIKUN

Assignees

• 江苏大学

Dates

Publication Date

20260508

Application Date

20251120

Claims (10)

1. 1. The utility model provides a hedging type combustor for high-efficient desorption of ammonia hydrogen combustion nitrogen oxide, includes the combustor body, main fuel injection port, secondary fuel injection port and gas vent have in the combustor body, main fuel injection port with secondary fuel injection port sets up relatively, and main fuel follows main fuel injection port gets into the combustor, and secondary fuel follows secondary fuel injection port gets into the combustor, and two air current are carried and are formed the hedging flow field along opposite direction in the combustor, and the gas after the hedging reaction is followed the gas vent is discharged the combustor.
2. 2. The opposed firing burner of claim 1, wherein the primary fuel is an ammonia-hydrogen/air premixed gas at stoichiometric ratio and the secondary fuel is pure ammonia.
3. 3. The hedging burner of claim 2, wherein the secondary fuel injection ratio is 0.025-0.4.
4. 4. The opposed firing burner of claim 3, wherein the secondary fuel injection ratio is 0.2.
5. 5. The opposed firing burner of claim 1, wherein the secondary fuel injection ports are provided with a first baffle and a second baffle, the first and second baffles circumscribing to form a gas passage, the ends of the gas passage forming secondary fuel injection points.
6. 6. The opposed firing burner of claim 5, wherein the exhaust ports include a first exhaust port and a second exhaust port, the first and second exhaust ports being located on either side of the gas passage.
7. 7. The opposed firing burner of claim 5, wherein the cross-section of the inner wall surfaces of the first and second baffles is straight or wavy or zigzag.
8. 8. The opposed firing burner as claimed in claim 5, wherein the relation of the injection port width (W) to the burner channel width (W) is satisfied with 2/9≤w/w≤5/9.
9. 9. The opposed firing burner of claim 5, wherein the relationship of the baffle axial length (L) to the burner length (L) is 1/6≤l/l≤5/6.
10. 10. The opposed firing burner of claim 5, wherein the burner body, the first baffle, and the second baffle are each fabricated from 316 stainless steel via a wire-cut electrical discharge machining process.

Description

Opposite-impact burner for high-efficiency removal of nitrogen oxides by ammonia-hydrogen combustion Technical Field The invention belongs to the field of energy and combustion, and particularly relates to a opposed burner for efficiently removing nitrogen oxides by ammonia-hydrogen combustion. Background In the background of the growing prominence of energy crisis and global warming, the development of zero-carbon or low-carbon alternative energy sources suitable for power and propulsion systems has become a consensus in the combustion field. In recent years, ammonia has received extensive attention from academia and industry as a carbon-free fuel by virtue of a mature manufacturing process, a well-established storage and transportation infrastructure, and a high volumetric energy density. However, compared to conventional fossil fuels, ammonia has a lower laminar flame speed at normal temperature and pressure, which is only about one fifth of the flame speed of methane under the same conditions, so blending combustion is often employed to improve its combustion performance. Hydrogen is used as the gas fuel with the simplest structure, has higher laminar flame speed and wide flammability limit, and makes the mixed combustion of ammonia and hydrogen become a research hot spot. However, nitrogen elements in ammonia molecules are easy to generate a large amount of fuel nitrogen oxides in the combustion process, so that the ammonia not only endangers human health, but also can cause negative influence on the environment. Therefore, developing efficient nitrogen oxide emission reduction technologies is an important challenge for current ammonia-hydrogen combustion systems. Disclosure of Invention The invention provides a hedging type combustor suitable for ammonia-hydrogen combustion, which introduces reducing agent ammonia through hedging mode, fully mixes and reacts with formed nitrogen oxides to convert the nitrogen oxides into nitrogen and water, and aims to solve the technical challenge of high nitrogen oxide emission in the ammonia-hydrogen combustion process so as to meet increasingly strict environmental protection emission regulations. The invention adopts the following technical scheme that the opposite-flow type combustor comprises a combustor body, wherein a main fuel injection port, a secondary fuel injection port and an exhaust port are arranged in the combustor body, the main fuel injection port and the secondary fuel injection port are arranged opposite to each other, main fuel enters the combustor from the main fuel injection port, secondary fuel enters the combustor from the secondary fuel injection port, two airflows are conveyed in opposite directions in the combustor and form opposite-flow fields, and gas after opposite-flow reaction is discharged out of the combustor from the exhaust port. In one possible implementation, the primary fuel is a stoichiometric ammonia hydrogen/air premix gas and the secondary fuel is pure ammonia gas. In one possible implementation, the secondary fuel is pure ammonia and the secondary fuel injection ratio is 0.025-0.4. In one possible implementation, the secondary fuel injection ratio is 0.2. In one possible implementation, the secondary fuel injection port is provided with a first baffle and a second baffle, which surround to form a gas channel, and the end of the gas channel forms a secondary fuel injection point. In one possible implementation, the exhaust port includes a first exhaust port and a second exhaust port, the first exhaust port and the second exhaust port being located on two sides of the gas channel, respectively. In one possible implementation, the cross sections of the inner wall surfaces of the first baffle plate and the second baffle plate are straight or wavy or zigzag. In one possible implementation, the relation of the injection port width (W) to the burner channel width (W) is satisfied, 2/9≤w/w≤5/9. In one possible implementation, the relationship of the baffle axial length (L) to the burner length (L) is satisfied with 1/6≤l/L≤5/6. In one possible implementation, the burner body, the first baffle, and the second baffle are each fabricated from 316 stainless steel via a wire-cut electric discharge machining process. Advantageous effects The opposite-flow type combustor for efficiently removing the nitrogen oxides by ammonia-hydrogen combustion realizes full combustion reaction by constructing an opposite-flow combustion flow field and combining the accurate introduction of main fuel and secondary fuel with the regulation and control of a reaction zone. Taking ammonia-hydrogen combustion as an example, the high-efficiency reduction and removal of nitrogen oxides in the ammonia-hydrogen combustion process are realized. The technical idea has good universality and can be widely applied to other amino fuel combustion systems. Fresh ammonia hydrogen/air premixed gas enters the burner from the main fuel injection port, and after ignition by