The mixed combustion technology of hydrogen-rich gas boiler improves combustion efficiency and reduces pollutant emissions from the root through the scientific ratio of hydrogen and natural gas and precise control of the combustion process, thus achieving the coordinated optimization of energy utilization and environmental performance. This technology is not a simple gas mixing, but a complementary design based on the characteristics of the two fuels, making high efficiency and cleanliness possible.
The high combustion speed of hydrogen enhances the completeness of combustion. The flame propagation speed of hydrogen is much higher than that of natural gas. When the two are mixed and burned, hydrogen can drive the natural gas to complete the oxidation reaction faster, reducing the waste of unburned fuel. In the burner, after the mixed gas is ignited, the rapid combustion characteristics of hydrogen allow the flame to spread to the entire combustion area in a shorter time, ensuring that the natural gas molecules are fully exposed to oxygen and avoiding energy loss caused by incomplete combustion. This fast and complete combustion process directly improves the thermal energy conversion rate of the fuel, allowing the same volume of fuel to release more available heat.
The dynamic optimization of the mixing ratio balances combustion efficiency and stability. The technical system will automatically adjust the mixing ratio of hydrogen and natural gas according to the load of the hydrogen-rich gas boiler (such as the level of heating demand): when the load is high, the proportion of hydrogen will be appropriately increased to increase the combustion intensity by using its high calorific value characteristics; when the load is low, the proportion of natural gas will be increased to ensure the stability of combustion. This flexible ratio avoids the efficiency fluctuation of a single fuel under different loads, allowing the hydrogen-rich gas boiler to maintain efficient operation in the full range of operating conditions, reducing energy waste caused by load changes.
Precise control of combustion temperature reduces heat loss. The flame temperature during hydrogen combustion is high, but the mixed combustion technology controls the flame temperature within a reasonable range by adjusting the excess air coefficient - both ensuring the temperature required for full combustion of the fuel and avoiding the heat loss caused by excessive temperature through the furnace body. At the same time, the high-temperature flame has a stronger thermal radiation capacity and can more effectively transfer heat to the heating surface of the hydrogen-rich gas boiler (such as the water-cooled wall), reducing the heat loss carried away by the flue gas and allowing more heat energy to be converted into the energy required for heating or hot water.
The clean combustion characteristics of hydrogen reduce the generation of pollutants from the source. The main product of hydrogen combustion is water, and no carbon oxides (such as carbon monoxide, carbon dioxide) and sulfides are produced. During mixed combustion, the addition of hydrogen reduces the consumption of natural gas per unit heat output, which is equivalent to reducing the combustion of carbon-based fuels, thereby reducing the emissions of carbon dioxide and carbon monoxide. For carbon monoxide, the full combustion characteristics of hydrogen can also promote the complete oxidation of hydrocarbons in natural gas, further reducing the carbon monoxide produced by incomplete combustion.
Low-nitrogen combustion technology and mixed combustion synergistically reduce nitrogen oxides. The formation of nitrogen oxides is closely related to the combustion temperature. High temperature will cause nitrogen in the air to react with oxygen to produce a large amount of nitrogen oxides. Mixed combustion technology optimizes the mixing method of hydrogen and natural gas to make the flame temperature more evenly distributed and avoid the formation of local high-temperature areas; at the same time, the rapid combustion of hydrogen shortens the residence time of the fuel in the high-temperature area and reduces the chance of nitrogen oxides. This synergistic effect makes the concentration of nitrogen oxide emissions significantly lower than that of pure natural gas combustion, meeting more stringent environmental protection standards.
The structural design of the burner enhances the uniformity of gas mixing. The burner supporting the mixed combustion technology adopts a multi-channel air intake design. Hydrogen and natural gas enter the burner head through independent channels respectively, and are disturbed by multiple layers of porous plates before being ejected to form a uniform premixed gas. This uniform mixing makes the combustion process more stable, avoiding incomplete combustion or high-temperature generation caused by local hypoxia or oxygen enrichment, which not only improves efficiency but also reduces pollutants generated by uneven mixing (such as carbon monoxide generated by local hypoxia).
Flue gas circulation technology further recovers energy and reduces emissions. The flue gas recirculation device set at the rear of the hydrogen-rich gas boiler introduces part of the low-temperature flue gas into the combustion zone, and mixes it with the mixed gas to participate in combustion again. This not only reduces the oxygen concentration and temperature in the combustion zone and inhibits the generation of nitrogen oxides, but also utilizes the waste heat in the flue gas to improve the overall thermal efficiency of the hydrogen-rich gas boiler. The recovered waste heat is equivalent to reducing fuel consumption, indirectly reducing the total amount of pollutant emissions, and forming a virtuous cycle of efficiency improvement and environmental protection and emission reduction.
Through the complementary characteristics of hydrogen and natural gas, precise control of the combustion process, and coordination with environmental protection technologies, the mixed combustion technology allows the hydrogen-rich gas boiler to significantly reduce pollutant emissions while efficiently utilizing energy, becoming an advanced technical solution that takes into account both economy and environmental protection.
