Burner Tip Plate Oblique Angle for Low NOx Emissions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing premix burners fail to achieve low NOx emissions below 15 ppm with residual oxygen levels below 3% and are not compatible with commercially available boilers, leading to inefficiencies and non-compliance with stringent emission standards.
Innovation Solution
A burner design featuring a combustion head with a tip plate and two concentric tubes, where the inner tube is used for cooling and the outer tube is configured with apertures to direct the air-fuel mixture at an angle, creating a conical flame that reduces NOx emissions and enhances return flows, while mechanical adjustment elements allow for optimal flame temperature control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a long combustion head is used to achieve low NOx emissions, then NOx emissions are reduced, but residual oxygen remains high and compatibility with commercial boilers is limited
Solution Approach 1:
The combustion head is divided into multiple functional sections: a first section remaining outside the boiler and a second section extending into the boiler interior. This segmentation allows the burner to maintain an extended effective combustion length for low NOx emissions while keeping the external frame compact for commercial boiler compatibility.
Solution Approach 2:
The tip plate is oriented at an oblique angle (40-80 degrees) relative to the longitudinal axis of the combustion head, directing the air-fuel mixture at an angle into the boiler. This angular orientation creates a conical flame pattern that extends the combustion path in three dimensions, achieving low NOx emissions without requiring a linearly long combustion head.
2Object-generated harmful factors
If a long combustion head is used to achieve low NOx emissions, then NOx emissions are reduced, but residual oxygen remains high
Solution Approach 1:
The oblique tip plate orientation directs the air-fuel mixture at 40-80 degrees from the longitudinal axis, creating a conical flame that extends combustion in multiple directions. This dimensional approach increases the effective combustion path length, ensuring more complete fuel consumption and lower residual oxygen without requiring a linearly extended combustion head.
Solution Approach 2:
The angle of the tip plate (40-80 degrees) is optimized to achieve the right balance between flame extension and combustion efficiency. This parameter optimization allows the burner to maintain low residual oxygen levels while achieving low NOx emissions through the conical flame pattern.
3Object-generated harmful factors
If the tip plate directs gas flow at an oblique angle to create conical flame, then NOx emissions are reduced, but flame temperature distribution becomes complex
Solution Approach 1:
The tip plate creates different flame temperature zones: a cooler conical flame region and a hotter return flow region. This local temperature differentiation allows the burner to achieve low overall NOx emissions while maintaining sufficient local temperatures for complete combustion. The cooler conical flame reduces thermal NOx formation, while the hotter return flow ensures complete fuel consumption.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The burner achieves NOx emissions below 15 ppm with residual oxygen levels below 3%, and below 5 ppm with residual oxygen levels below 6%, while being compatible with commercially available boilers, thus meeting stringent emission standards and improving operational efficiency.
Implementation Method 1
the inner tube is additionally provided with a supply of combustion air for conveying the combustion air through the tip plate's air openings... for cooling the tip plate
Implementation Method 2
between a side edge of the tip plate and the plane of the tip plate is an oblique angle of incidence for directing a gas delivered forward of the tip plate away from the longitudinal center axis of the combustion head
Implementation Method 3
a burner capable of being installed to a boiler for burning a premixed air-fuel mixture
Data Source
Figure 1~2
Figure 3A~3B
Figure 4A~4B
AI summary
The invention relates to a burner installable to a boiler for burning a premixed air-fuel mixture, said burner comprising a frame member provided with elongated combustion head protruding from the frame member and having what in a view from the frame member is its distal end provided with a tip plate. In said burner - between a side edge of the tip plate and the plane (R) of the tip plate is an oblique angle of incidence (a) for directing a gas delivered forward of the tip plate away from the longitudinal center axis of the combustion head, - the combustion head has its tip plate provided with a plurality of air openings extending through the tip plate and it is for cooling the tip plate that the inner tube is additionally provided with a supply of combustion air for conveying the combustion air through the tip plate's air openings. The invention relates also to a boiler-burner assembly.