Wall-Bound Burner Non-Uniform Injection for NOx Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In furnaces with multiple rows of burners, burners near walls and corners produce higher NOx emissions due to increased interaction with the furnace walls, existing methods either incur high capital expenses or reduce efficiency, and fail to effectively differentiate between wall-bound and non-wall-bound burners.
Innovation Solution
Implementing non-uniform injection properties for wall-bound burners in up-fired or down-fired reformers, where the injection properties, such as angle, flow rate, and oxidant/fuel ratios, differ from non-wall-bound burners to create a heat profile with higher heat density distal to the walls, reducing NOx generation and flame volume.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If burners positioned in close proximity to walls and/or corners are used, then burner density and heat distribution are improved, but NOx emissions increase due to greater wall interaction
Solution Approach 1:
The patent applies different combustion air ratios to different burner locations. Wall-bound burners use stoichiometric (100%) combustion air to stabilize flames and prevent soot, while non-wall-bound burners use reduced air ratios (60-80%) to minimize NOx. This local differentiation resolves the contradiction by optimizing each burner's operation according to its specific spatial conditions.
2Stability of the object's composition
If stoichiometric combustion air is provided to wall-bound burners to stabilize flames, then flame stability is improved, but flame temperature and heat interaction with walls increase, producing more NOx
Solution Approach 1:
The patent differentiates combustion air provision by burner location. Wall-bound burners receive stoichiometric air for stability, while non-wall-bound burners receive reduced air ratios. This localized approach allows flame stabilization where needed without unnecessarily increasing NOx production throughout the entire furnace.
3Object-generated harmful factors
If cooling fluid is used to selectively cool regions of high NOx generation, then NOx generation is reduced, but capital expense and equipment complexity increase
Solution Approach 1:
Instead of adding cooling systems, the patent changes the combustion parameters (combustion air ratios) for different burner types. By adjusting the air-to-fuel ratio parameter locally at each burner, the system reduces NOx generation through fundamental combustion control rather than adding complex post-combustion cooling equipment.
4Object-generated harmful factors
If cooling fluid is used to reduce NOx, then NOx emissions are reduced, but efficiency decreases due to reduced heat absorption by process
Solution Approach 1:
The patent reduces NOx by changing combustion parameters (air ratios) rather than using cooling fluids. This approach maintains full heat recovery efficiency because the combustion process itself is optimized, not interrupted by cooling systems that would steal heat from the process.
5Device complexity
If uniform combustion air ratios are used for all burners, then system simplicity is maintained, but wall-bound burners cannot be optimized for their specific conditions
Solution Approach 1:
The patent implements differentiated combustion air ratios based on burner location. Wall-bound burners receive stoichiometric air for optimal stability, while non-wall-bound burners receive reduced air ratios for optimal NOx control. This localized optimization improves overall system reliability without creating excessive complexity.
Solution Approach 2:
The patent segments the burner system into wall-bound and non-wall-bound categories, applying different combustion air ratios to each segment. This segmentation allows optimized performance for each burner type while maintaining manageable system complexity through clear classification and standardized control strategies.
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
This approach reduces NOx emissions, decreases burner interaction with the wall, and achieves high efficiency with lower capital expenses by optimizing flame control and heat distribution.
Implementation Method 1
combusting a fuel in a combustion region of an up-fired or down-fired reformer
Implementation Method 2
forming non-uniform injection properties with a wall-bound burner... generate a heat profile that provides a second heat density distal from the one or more walls that is greater than a first heat density proximal to the one or more walls
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
A method of combustion and a reformer. The method includes combusting a fuel in a combustion region of an up-fired or down-fired reformer and forming non-uniform injection properties with a wall-bound burner. The combusting is performed in a combustion region by burners, wherein at least one of the burners is the wall-bound burner forming the non-uniform injection properties. The non-uniform injection properties generate a heat profile providing a first heat density proximal to a wall and a second heat density distal from the wall, the second heat density being greater than the first heat density. The non-uniform injection properties are formed by injection properties selected from an angle of one or more injectors, a flow rate of one or more injectors, an amount and/or location of oxidant injectors, an amount and/or location of fuel injectors, and combinations thereof.