低NOx工业燃气燃烧技术研究进展

随着环保政策对工业炉NOx排放的限制越来越严格，需要开发新型低NOx燃烧器，以对现有加热炉进行改造。本文介绍了燃气燃烧过程中NOx的形成机理，综述了燃料分级（再燃）燃烧、旋流燃烧、脉动供燃料燃烧、富氧燃烧以及温和与深度低氧稀释（MILD）燃烧等几种新型低NOx燃烧技术。结合石化管式加热炉结构和管内流体的特点指出：在不对现有炉子整体结构做改造的情况下通过设计新型结构的燃料分级燃烧器能够减少加热炉NOx的排放；旋流技术能够强化反应物的混合与燃烧过程，然而其对NOx生成量的影响尚需进一步研究；MILD燃烧技术在体积热强度高的加热炉上较容易实现。多种低NOx燃烧技术组合使用会取得比单一措施更好的效果。

Research progress on low-NOx industrial gas combustion technology

According to the mechanism of NOx formation during gas combustion，several low-NOx combustion technologies such as fuel-staged (reburning) combustion，swirling combustion，oscillating combustion，oxygen-fuel combustion and moderate & intense low-oxygen dilution combustion (MILD) were reviewed in this paper. Taking into account the characteristics such as structure and fluid in tube of petrochemical tubular furnace，the following conclusions were presented. Without changing the overall furnace conformation，a novel structure burner achieving fuel-staged combustion can be applied to reduce NOx emission. The swirling combustion will enhance mixing and combustion of reactants，but the impact on NOx formation needs further study. MILD combustion will occur more easily in higher heat release intensity furnace than the lower one. Also a combination of more than one low-NOx combustion technology will achieve better results than a single method.