微富氧环境下煤粉/高炉煤气掺烧锅炉燃烧过程数值模拟

Numerical simulation on combustion process of a pulverized coal/blast furnace gas combined combustion boiler in micro-oxygen-enriched atmosphere

提出将钢铁企业的放散氧气回收送入其自备电厂混烧锅炉,使炉内形成微富氧燃烧。通过Fluent数值模拟软件对微富氧工况下混烧锅炉的炉内燃烧过程进行数值模拟和热力计算。结果表明:随着助燃空气中氧气浓度的增加,炉内温度水平明显升高,延长了煤粉在炉内的停留时间,增加了辐射换热量,提高了锅炉热效率;氧气浓度的增加还有助于混烧锅炉掺烧部分低热值高灰分烟煤。

Because part of the diffusing oxygen cannot be fully utilized and diffused in the iron and steel enterprises,a new method of diffusing oxygen recycling was proposed,in which the diffusing oxygen is sent to the co-combustion boiler of captive power plant to form micro-oxygen-enriched atmospheres.Numerical simulation and thermodynamic calculation on the combustion process in the combined combustion boiler in micro-oxygen-enriched atmosphere were carried out,by using the Fluent software.The results show that：with an increase in the concentration of oxygen,the temperature in furnace rose obviously,which prolonged the residence time of pulverized coal in furnace,enhanced the radiation heat transfer and improved the boiler thermal efficiency.Moreover,it was helpful for co-firing of the pulverized coal and some bituminous coal with low calorific value and high ash content.