300 MWCFB锅炉提高SO_2超低排放经济性试验研究

为了提高锅炉机组SO_2超低排放的经济性,在某300 MWCFB锅炉开展了实炉试验,研究了CFB锅炉炉内干法脱硫与CFB-FGD脱硫相结合的两级联合脱硫技术。结果表明:通过理论分析和试验室检测可优选出炉内干法脱硫和CFB-FGD的最佳脱硫剂品种。CFB锅炉运行参数中负荷的变化同时影响两级脱硫效率。随着锅炉负荷的升高,床温和脱硫塔入口温度均呈现上升趋势。床温的升高降低了炉内脱硫效率,脱硫塔入口温度的上升提高了CFB-FGD脱硫效率。按照推荐的石灰石和生石灰物化参数及两级脱硫系统匹配方式运行,锅炉净烟气SO_2浓度满足超低排放限值要求,炉内干法脱硫与CFB-FGD脱硫剂耗量均下降,提高了SO_2超低排放的经济性,降低了脱硫成本。

Experimental study on improving the SO2 ultra low emission economy of 300 MWCFB boiler

In order to improve the economy of SO2 ultra low emission of boiler unit,a real boiler test has been carried out in a 300 MWCFB boiler.The two stage combined desulfurization technology combined with dry desulfurization and CFB-FGD desulfurization in CFB boiler has been studied.The results show that the best desulfurizer varieties in dry process desulfurization and CFB-FGD can be optimized by theoretical analysis and laboratory test.The change of load in the operation parameters of CFB boiler affects two stage desulfurization efficiency at the same time.With the increase of the boiler load,the boiler bed temperatrue and inlet temperature desulfurization tower all show an upward trend.The increase of bed temperature reduces the desulfurization efficiency in the furnace,and the increase of the inlet temperature of desulfurization tower improves desulfurization efficiency of CFB-FGD.In accordance with the recommended limestone and lime physical and chemical parameters and two stage desulfurization system matching operation,the SO2 concentration in boiler flue gas meets the requirements of ultra-low emission limits.The dry desulfurization and CFB-FGD desulfurizer consumption in the furnace both decrease,and the economic efficiency of SO2 ultra low emission is improved,and the desulfurization cost is reduced.