凹凸棒黏土对燃煤PM2.5排放及团聚捕集特性影响

在固定床反应系统上考察凹凸棒黏土对燃煤可吸入颗粒物PM_2.5的排放及团聚捕集特性影响,分析凹凸棒黏土添加量以及添加凹凸棒黏土情况下燃烧气氛、燃烧温度和钙硫物质的量比等参数对燃煤PM_2.5的数量浓度、质量浓度以及团聚捕集率的影响规律。结果表明,煤燃烧过程中添加凹凸棒黏土可以显著降低PM_2.5排放浓度,凹凸棒黏土的添加量不宜超过3%(质量分数);空气气氛下燃烧产生的PM_2.5多于O₂/CO₂气氛;随着钙硫物质的量比的增大,PM₁的质量浓度减小,但PM_1~2.5的质量浓度增大,颗粒物的粒径有向更大粒径转移的趋势;燃烧温度的升高会促进PM_2.5各粒径范围颗粒物的生成,降低了凹凸棒黏土对PM_2.5团聚捕集率。

Effect of attapulgite on PM2.5 emission and agglomeration during coal combustion

Effect of attapulgite on PM_2.5 emissions and agglomeration during coal combustion was investigated in a fixed bed system. The effects of addition amount, combustion temperature, mole ratio of calcium to sulfate and combustion atmosphere on mass and number concentration and collection efficiency of PM_2.5 were analyzed. The results show that attapulgite added during coal combustion can effectively reduce PM_2.5 emissions. The suitable amount of attapulgite is no more than 3%. PM_2.5 emission during coal combustion in air is higher than that in O₂/CO₂ atmosphere. PM₁ mass concentration decreases with increasing mole ratio of calcium to sulfate, while PM_1~2.5 mass concentration increases, indicating an increasing trend in particle size. Increasing combustion temperature will increase PM_2.5 emission and reduce its collection.