大型循环流化床发电机组在烟气污染物超低排放的限制下，仅靠炉内脱硫难以满足要求，需在炉外联用烟气脱硫系统，二者脱硫有机匹配能够降低综合脱硫成本。为确定电厂运行过程中两级联合深度脱硫最佳脱硫分配比例，实现满足排放标准下最低的脱硫成本。根据多种成本因素，建立技术经济计算模型分析不同炉内钙硫比（物质的量之比）对脱硫分配比例的影响及主要成本因素，并研究不同石灰石价格和厂用电价在不同炉内钙硫比下对综合脱硫成本的影响。结果表明，炉内钙硫比为1.0、1.1～1.5、1.6、1.7～2.1时，最佳炉内脱硫份额分别为70%、60%、85%和80%；炉内脱硫对锅炉热效率有较大影响，且钙硫比越高影响越大，当炉内钙硫比超过2.0时，炉内脱硫热损失会降低锅炉热效率；炉内脱硫的主要成本因素是石灰石粉和运行电耗成本，石灰石/石膏湿法烟气脱硫的主要成本因素为石灰石浆液和吸收塔运行电耗成本，且随脱硫分配比例不同有明显变化；不同的石灰石价格和厂用电价在不同炉内钙硫比下具有不同的最佳脱硫分配份额。

Under the restriction of ultra-low emission of flue gas pollutants, the large-scale circulating fluidized bed generator sets can not meet the requirements by desulfurization in the furnace lonely, and need to use a flue gas desulfurization system outside the furnace. The organic matching of the two desulfurization can reduce the comprehensive desulfurization cost. The optimal desulfurization distribution ratio of two-stage combined deep desulfurization in the operation process of power plant can achieve the lowest desulfurization cost under the emission standard. According to a variety of cost factors, a technical and economic calculation model was established to analyze the influence of different furnace calcium-sulfur ratios on the desulfurization distribution ratio and main cost factors, and explore the impact of different limestone prices and plant electricity prices on the comprehensive desulfurization cost. The results show that when the ratio of calcium to sulfur in the furnace is 1.0, 1.1-1.5, 1.6, 1.7-2.1, the best desulfurization shares in the furnace are 70%, 60%, 85% and 80%, respectively. Furnace desulfurization has great influence on boiler thermal efficiency, and the higher the molar ratio of calcium to sulfur, the greater the influence. When the ratio of calcium to sulfur exceeds 2.0, the heat loss of in-furnace desulfurization can reduce boiler thermal efficiency. The main cost factors of in-furnace desulfurization are limestone powder cost and operation power consumption cost, and the main cost factors of limestone/gypsum wet flue gas desulfurization are limestone slurry cost and absorption tower operation power consumption cost, which have obvious changes with different desulfurization distribution ratio. Different limestone prices and factory electricity prices have different optimal desulfurization distribution shares under different conditions of calcium-sulfur ratio in the furnace.

0 引言

1 河坡发电脱硫设备

   1.1 CFB锅炉炉内喷钙脱硫

   1.2 炉外烟气石灰石/石膏湿法脱硫

   1.3 废水处理系统

2 两级脱硫系统成本因素及计算方法

   2.1 石灰石制备成本价格估算

   2.2 炉外脱硫效率的计算方法

   2.3 炉内脱硫成本计算方法

   2.4 石灰石/石膏湿法脱硫成本计算方法

3 计算结果分析及优化

   3.1 机组炉内脱硫运行情况

   3.2 计算条件

   3.3 不同钙硫比下脱硫分配比例对综合脱硫成本的影响

   3.4 不同钙硫比下脱硫分配比例对单项成本的影响

   3.5 石灰石和厂用电价格对综合脱硫成本的影响

4 结论