| Regenerative high temperature air combustion (HTAC) technology is an advanced technology which has started since 1980s. It has many advantages such as energy saving, environmental protection and so on. Regarding the U-shaped radiant tube in oil heating furnace as the research object, this paper has mainly studied on the combustion characteristics of HTAC, the optimization of burner structure and operation parameters, and research of engineering application. At the same time, analyze its physical-chemical characteristics and mechanism of low oxygen and HTAC in the furnace. Study on the measures to improve the burner efficiency, ensure the combustion stability and lower the pollutants emission. In order to determine the effect of structural factors, numerical simulation was used to study the effect of factors including the shape of air nozzle, secondary air nozzle angles (a), radial distance of third air (L) and axial distance of third air (H) on radiation tube temperature distribution and NO emission. The results proved that furnace works at the optimizing structural when the shape of air nozzle is sector annular, a=60°, L=114mm, H=45mm. The NO emission concentration was 36.1ppm. Response surface method was used to analysis the air-staged proportion, air preheat temperature and air excess ratio of three factors on the temperature distribution and pollutants emission in radiation tube. The optimal operation parameters are obtained. The paper also completed the transformation of the furnace program and field test program. Evaluation result showed that the water jacket furnace thermal efficiency was 9.35% higher than that of the conventional water jacket furnace after transformation; the NO emission concentration was 32.3% lower than that of the existing water jacket heater and so achieved the purpose of energy saving and emission reduction. |
PDF Full Text Request