【摘要】 针对某220 t/hП型高压锅炉,综合考虑锅炉现有设备和系统的特点,根据方案简单易行、投资少以及同时兼顾空气燃烧和富氧燃烧等原则提出了富氧燃烧改造方案。为实现一次风和二次风的分离加热,改造方案采取将后三级受热面分仓隔离的方式。锅炉其他受热面保持不变。通过对不同的漏风形式采取相应的处理措施,确保改造方案的漏风率降至较低水平。对改造方案进行性能分析,结果表明:改造后的富氧燃烧条件下的锅炉热效率高于空气燃烧条件,富氧燃烧条件下的绝热燃烧温度低于空气燃烧条件约200℃,锅炉各级受热面的烟气侧出口温度均略低于空气燃烧条件,锅炉本体排烟温度高于烟气酸露点。更多还原

【Abstract】 The oxy-fuel retrofit proposal on a 220 t/h high-pressure boiler was performed with considerations of the present equipment and sub-systems in the boiler system. The principles of minimizing the amount of retrofit work and the compatibility of the work modes of both air-firing and oxy-fuel. To realize the separately heating of primary and secondary recirculating flue gases, a division plate was set between each of the last three heating surfaces in the flue gas flowing direction. Meanwhile the other heating surfaces in the boiler were kept unchanged. Appropriate measures were adopt for various types of air leakages, which make sure the minimum air leakage ratio. The performance analysis was also performed. The result shows that the thermal efficiency of oxy-fuel boiler is higher than that of air-firing boiler. The adiabatic temperature of oxy-fuel boiler is lower about 200 ℃ than that of air-firing boiler. The outlet flue gas temperatures of all heating surfaces are all slightly lower than those of air-firing boiler. The outlet flue gas temperature of the last heating surface is higher than the local acid dew point of flue gas.更多还原