2种活性炭协同布袋除尘对垃圾焚烧厂烟气中二恶英的去除

Removal of dioxins in flue gas from a MSWI using two kinds of activated carbons with baghouse filtration

考察了2种活性炭(活性炭A和活性碳B)对垃圾焚烧厂烟气中二恶英去除率的影响。通过采集与分析垃圾焚烧厂"活性炭喷射+布袋除尘"协同处置工艺前口和后口的烟气样品,得到前后口2,3,7,8-PCDD/Fs的浓度,并计算去除率。结果表明:2种活性炭对2,3,7,8-PCDFs的去除率相当,均为99%左右;而对2,3,7,8-PCDDs的去除率略低,分布在83.3%~99.9%之间,并且活性炭A的去除率高于活性炭B。通过对2种活性炭性能指标测试结果的比较,具备更丰富的中孔以及更大的微孔、中孔平均孔径可能是活性炭A去除率更高的原因。此外,比较了活性炭在不同投加速率(5、10和15 kg·h^(-1))下对二恶英的去除率,发现低投加速率时二恶英去除率随投加速率的增加而增加,而当投加速率从10 kg·h^(-1)增加到15 kg·h^(-1)时二恶英去除率无明显变化。

Removal efficiencies of dioxins by two different types of activated carbon（ A and B） were investigated in the present work. The concentrations of 2,3,7,8-PCDD / Fs in flue gas samples collected before and after treatment by activated carbon injection and a bag filter were measured to calculate the removal rates of these compounds. The removal rates of 2,3,7,8-PCDFs using activated carbons A and B were similar,with values up to 99%. The removal rates of 2,3,7,8-PCDDs（ 83. 3% to 99. 9%） were slightly lower than those of 2,3,7,8-PCDFs. Activated carbon A is more efficient at removing 2,3,7,8-PCDDs than activated carbon B,which may be due to the greater number of mesopores and higher average pore sizes for both micropores and mesopores of activated carbon A. Dioxin removal rates achieved by activated carbon under different injection rates were also estimated. The removal rate increased on increasing the injection rate from 5 kg·h^-1to 10 kg·h^-1and then changes little as the injection rate increased to 15 kg·h^-1.