1000 MW燃煤锅炉掺烧生物质的数值模拟

Numerical Simulation of Mixed Biomass in 1000 MW Coal-fired Boiler

生物质能是循环可再生能源,能实现可持续发展。为了节约煤炭资源,探究将生物质能利用于燃煤电站锅炉,研究生物质与煤混燃的可行性。以某电厂1000 MW超超临界旋流对冲锅炉为研究对象,运用Gambit软件搭建模型,导入Fluent软件,研究纯燃煤工况以及生物质掺烧比为20%的混燃工况,其中混燃工况包含生物质从不同喷口位置喷入的5种工况。通过分析各工况时炉膛的速度场、温度场、烟气组分和污染物NOx的变化趋势,确定出最佳的燃烧工况。结果显示:相比于纯燃煤工况,混燃时降低了炉膛内最高温度、提高了炉膛出口温度、降低了炉膛出口的O_(2)浓度、减少了NO的排放量、促进了燃料的燃烧。各混燃工况相比较,在不改变锅炉结构情况下,从最上层燃烧器喷入生物质时降低污染物NO的排放最明显。

Biomass energy is a circular and renewable energy source,which can achieve sustainable development.In order to save coal resources,the use of biomass in coal-fired power plant boiler was explored to study the feasibility of mixed combustion of biomass energy and coal.Taking the 1000 MW ultra-supercritical swirl boiler in a power plant as research object,we used Gambit software to build the model,and introduced Fluent software to study the pure coal burning condition and biomass mixed combustion condition with 20%biomass.The mixed combustion conditions include five working conditions of biomass being injected from different nozzle positions.By analyzing the change trend of furnace speed field,temperature field,flue gas component and pollutant NOx in each working condition,the best combustion condition was determined.The results show that compared with pure coal burning,in the process of mixed combustion,the highest temperature in the furnace is reduced,which improves the temperature of the furnace outlet,reduces the O_(2) concentration of the furnace outlet,reduces the emission of NO,and promotes the combustion of fuel.When comparing the various mixed combustion conditions,the most significant reduction in pollutant NO emissions is achieved when biomass is injected from the uppermost burner without changing the boiler structure.