采用再燃技术降低锅炉Nox排放的工程实践

概述低NOx再燃技术在我国的试验研究及工程应用情况。通过试验台试验和数值模拟计算，并结合现场试验，为改造工程提供了最优化的方案，使工程应用达到了预期效果。将天然气作为再燃剂应用在一台50MW机组锅炉上，取得了NOx排放质量浓度降低44％的效果（天然气体积分数为15．6％）；将细煤粉作为再燃剂应用在一台65t／h煤粉炉上，取得了NOx排放质量浓度降低56．5％效果（再燃燃料质量分数为20％），成功实现了低NOx再燃技术在我国的工程应用。再燃技术的整个系统结构简单、运行操作方便、投资费用和运行成本都相对较低。实践证明，低NOx再燃技术是适应我国国情的高效低NOx燃烧技术，具有一定的应用前景。

Research and application of reburning technology to reduce Nox emission of coal-fired boiler

The experimental research and engineering application of low-NOx reburning technology in China were introduced in this paper. The experimental research (including experimental tests, computer simulation, combined with data from tests on site) provided optimal solution for engineering application and achieved expected results. The nature gas-reburning technology was put into practice on a 50 MW coal-fired boiler, through which NOx emission has been reduced by 44% (the fraction of nature gas was 15.6%); Meanwhile the pulverized coal-reburning technology was carried out on a 65 t/h coal-fired boiler, through which NOx emission has been reduced by 56.5% (the mass fraction of reburning fuel was 20%). The cases mentioned above mark the successful engineering application of reburning technology in China. The reburning technology has many advantages such as simple system, convenient operation, low investment and operation cost. According to local conditions, the reburning technology is high efficient and low NOx emission suitable for China and it is of bright application prospect.