玻璃熔窑中天然气/氢气混合燃料的燃烧过程仿真研究

Simulation of Combustion Process of Natural Gas/Hydrogen Hybrid Fuel in Glass Furnace

推动硅酸盐材料制造过程的低碳排放对于实现碳达峰、碳中和总体战略目标意义重大。本工作以平板玻璃窑炉为基础,采用数值模拟方法开展氢能在玻璃窑炉中应用的基础研究。分析采用天然气/氢气混合燃料对玻璃窑炉燃烧空间温度场/速度场分布、燃烧生成烟气成分的影响,预测氢能在玻璃窑炉中应用的可行性。结果表明,采用天然气/氢气混合燃料为玻璃液熔化提供能量,可以保证玻璃窑炉温度制度稳定。采用天然气/氢气混合燃料供能,燃料燃烧速率加快,释放热量集中,掺氢体积比为20%及以上时,燃烧形成的火焰长度会明显缩短,而热烟气在窑炉内停留时间延长。对比基础窑炉,采用掺氢比例40%的燃料,窑炉总烟气排放质量减少了4.13%,CO_(2)排放质量减少了12.50%,烟气中NOx浓度由1093 mg·Nm^(–3)(干燥,8%O_(2)条件下)增加至1282 mg·Nm^(–3)(干燥,8%O_(2)条件下)。为推动氢能在硅酸盐制造领域的应用还需开展燃烧系统设计、耐火材料侵蚀等方面研究,以解决氢能在大型窑炉中应用存在的问题。

Promoting the low carbon emission of silicate material manufacturing is of great significance to achieve the overall strategic goal of carbon peaking and carbon neutrality.In this paper,the application of hydrogen energy on a flat glass furnace was investigated by a numerical simulation method.The effect of natural gas/hydrogen hybrid fuel on the temperature/velocity fields and the composition of flue gas was analyzed to comprehensively evaluate the feasibility of hydrogen utilization in glass furnace.The results show that the combustion of natural gas/hydrogen hybrid fuel can ensure the temperature stability of glass furnace.Compared to natural gas,the burning rate of natural gas/hydrogen hybrid fuel is improved,and the heat release of fuel combustion is more concentrated.As the proportion of hydrogen increases to 20%or above,the flame length significantly shortens,and the residence time of flue gas at glass furnace increases.In the furnace with a hydrogen proportion of 40%,the total flue gas is reduced by 4.13%,and the CO_(2)emission is reduced by 12.50%,while the emission NO_(x)concentration is increased from 1093 mg·Nm^(–3)(dry with 8%O_(2))to 1282 mg·Nm^(–3)(dry with 8%O_(2)).A further investigation on combustion system design,refractory erosion and other aspects is proposed to solve the problems of hydrogen application in large glass furnace and promote the utilization of hydrogen energy in silicate materials manufacturing.