Premix Burner Radiant Strip Heating for Lower NOx Emissions
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current heating systems with radiant strips suffer from high NOx emissions, poor thermal efficiency, risk of backfires, high production and maintenance costs, and inefficient power modulation, leading to increased operational costs and environmental heat dispersion.
Innovation Solution
A premix burner with a cylindrical combustion head and modulating blower system that mixes fuel and air before combustion, allowing for extensive power modulation and reduced NOx emissions, combined with a heat exchanger to pre-heat air for the blower and a cooling mechanism to manage combustion chamber temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If conventional burners are used in radiant strip heating systems, then the system can provide heating function, but NOx emissions are high and thermal efficiency is poor
Solution Approach 1:
The patent applies parameter changes by modifying the combustion process parameters through pre-mixing fuel and air in specific ratios before combustion. This changes the combustion temperature and oxygen concentration parameters, resulting in reduced NOx emissions while improving thermal efficiency through more complete combustion.
Solution Approach 2:
The patent introduces an intermediary mixing chamber where fuel and air are mixed before entering the combustion zone. This intermediary step allows for controlled combustion with reduced peak temperatures, thereby reducing NOx formation while maintaining efficient energy conversion.
2Reliability
If high power ventilators are used to ensure sufficient air suction for combustion, then combustion reliability is improved, but system complexity and operational costs increase
Solution Approach 1:
The patent employs dynamic control of the ventilator operation, adjusting air supply based on actual combustion needs rather than maintaining constant high power operation. This dynamic approach ensures sufficient air mixing for reliable combustion while reducing overall system complexity and operational costs.
Solution Approach 2:
The patent performs preliminary mixing of fuel and air in a mixing chamber before combustion, ensuring proper stoichiometric ratios are achieved beforehand. This preliminary action reduces the need for high power ventilators during combustion, simplifying the system while maintaining combustion reliability.
3Area of stationary object
If radiant strips are extended to cover large areas, then heating coverage is improved, but heat loss to external environment increases
Solution Approach 1:
The patent changes the temperature parameter distribution along the radiant strip system, maintaining optimal combustion temperatures that maximize radiant heat output while minimizing convective losses to the external environment, thereby improving overall thermal efficiency across large coverage areas.
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 solution significantly reduces NOx emissions, enhances thermal efficiency, ensures safe and reliable operation, lowers gas and electricity consumption, and simplifies maintenance, while providing flexible power modulation and reduced noise and heat dispersion.
Implementation Method 1
a premix burner (5) with a cylindrical combustion head (12) on which a flame is generated by combustion of a fuel supplied to a modulating blower (14) for mixing with air
Implementation Method 2
combustion of a fuel supplied to a modulating blower (14) for mixing with air in the combustion chamber (6)
Implementation Method 3
the combustion chamber (6) being externally and uniformly touched and cooled by a recirculation flow of carrier fluid (F)
Implementation Method 4
adapted to be internally traversed by a heated carrier fluid constituted by exhaust gases... in order to heat the surrounding environment mainly by radiation
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
Heating system with radiant strips comprising a burner (5) housed in a containment structure (3) and provided with a combustion chamber (6) and with means (8) for supplying a fuel mixture and a ventilator (9), housed in the containment structure (3), provided with a fan (10) inserted in a recirculation duct (4) and operating in a suction fashion to force the carrier fluid (F) which traverses the radiant strips (2). The burner (5) is of premix type and comprises a conveniently cylindrical combustion head (12) provided with a metal mesh (13) on which the combustion occurs, and is extended into the combustion chamber (6) for at least the section (7') in which this traverses the recirculation duct (4). The supply means (8) of the burner (5) comprise a modulating blower (14) which suctions an adjustable flow, and an electropneumatic controlled valve (15), which is connected to a source of supply gas, and to the modulating blower (14) to which it is susceptible of sending a gas flow as a function of the air suctioned by the modulating blower (15), which are mixed together in the modulating blower (15) and injected by the latter in the combustion head (12) in order to obtain a flame on the cylindrical mesh (13) thereof.