循环流化床锅炉机组碳排放特性分析与计算  

Analysis and Calculation on Carbon Emission Characteristics of CFB Boiler Units

作　　者：高建强[1] 宋铜铜 张雪 GAO Jianqiang;SONG Tongtong;ZHANG Xue(School of Energy,Power and Mechanical Engineering,North China Eleetric Power University,Baoding 071003,Hebei Province,China;State Grid Qinhuangdao Power Supply Company,Qinhuangdao 066000,Hebei Province,China)

机构地区：[1]华北电力大学能源动力与机械工程学院,河北保定071003 [2]国网秦皇岛供电公司,河北秦皇岛066000

出　　处：《动力工程学报》2021年第1期14-21,共8页Journal of Chinese Society of Power Engineering

摘　　要：针对循环流化床(CFB)锅炉的特点,从燃煤过程、脱硫过程及锅炉辅机系统耗能3个方面分析了CFB锅炉机组的碳排放特性。根据CO2生成机理,分别给出了燃煤过程、炉内干法脱硫过程和炉外钙法烟气脱硫过程对应的单位标准煤CO2生成系数K计算方法,建立了适用于CFB锅炉机组的碳排放强度计算模型,以某300 MW CFB锅炉机组为例,利用该模型研究了煤质变化对单位标准煤CO2生成系数的影响以及碳排放强度随机组负荷的变化规律。结果表明:煤质、脱硫效率、钙硫比、机组负荷、锅炉辅机系统用电量及厂用电率是影响CFB锅炉机组碳排放强度的主要因素;低热值、高硫分煤种对应的单位标准煤CO2生成系数大于高热值、低硫分煤种对应的单位标准煤CO2生成系数;在煤质不变的情况下,CFB锅炉机组的碳排放强度与炉内钙硫比呈正相关,与机组负荷呈负相关,机组负荷平均每下降1%,碳排放强度升高2.41 g/(kW·h),且低负荷时碳排放强度随机组负荷下降而升高的幅度更大。Based on the features of circulating fluidized bed(CFB) boiler, the carbon emission characteristics were analyzed from the following three aspects: coal burning process, desulfurization process and auxiliary system energy consumption, etc. According to the CO2 generation mechanism, calculation methods were proposed for the CO2 generation coefficient K per unit standard coal consumption in the coal burning process, in-furnace dry desulfurization process and off-furnace calcium desulfurization process, respectively, while a calculation model was given for the carbon intensity of CFB boiler unit. Taking the 300 MW CFB boiler unit as an example, a study was conducted using the calculation model established to investigate the influence of coal quality change on the CO2 generation coefficient per unit standard coal consumption and the variation law of carbon emission intensity with the load of the CFB boiler unit. Results show that the coal quality, desulfurization efficiency, Ca/S ratio, unit load and the auxiliary power consumption are the main factors influencing the intensity of carbon emission of the CFB boiler. The CO2 generation coefficient per unit standard coal consumption corresponding to low calorific value and high sulfur coal is higher than that corresponding to high calorific value and low sulfur coal. Under the condition of a certain coal quality, the carbon emission intensity of CFB boiler is positively correlated with the Ca/S ratio in the furnace, and negatively correlated with the load of the unit;for every 1% decrease in load, the carbon emission intensity increases by 2.41 g/(kW·h), which increases by a greater extent with the decrease in unit load under low load conditions.

关 键 词：CFB锅炉 碳排放 炉内脱硫 钙硫比 计算模型 

分 类 号：TK229[动力工程及工程热物理—动力机械及工程]