半焦吸附剂烟气脱硫脱硝性能

Flue gas desulfurization and denitrification performance of the semi-coke adsorbents

采用廉价半焦为原料,经硝酸氧化和高温热处理改性后,负载金属氧化物制备半焦吸附剂,考察吸附剂的脱硫脱硝性能和再生性能,并利用BET、TEM和TPD等手段研究影响半焦吸附剂性能的内在因素。结果表明,当烟气组成为NO-O2-N2时,吸附剂具有良好的脱硝性能,失活吸附剂经水洗再生后,脱硝活性恢复较好;当烟气组成为SO2-O2-N2或SO2-NO-O2-N2时,吸附剂具有良好的脱硫性能,NO的存在能够显著提高脱硫活性,但脱硝活性迅速下降,失活吸附剂再生后,脱硝活性不能有效恢复。表征发现,SO2与NO在半焦吸附剂上均有一定的吸附量,而吸附剂的失活主要是由于孔道堵塞,表面性质发生了改变。

The semi-coke adsorbents were prepared by loading metal oxide on a cheap semi-coke material modifed through nitric acid oxidation and high temperature heat treatment. The desulfurization and denitrification and regeneration abilities were investigated. BET, TEM and SEM were employed to explore the effecting factors on the performance of the adsorbents. The results show that the adsorbents have a good denitrification activity and a regeneration ability with water washing when using NO-O2-N2 simulated flue gas. And the adsorbents exhibit an excellent desulfurization activity, especially with the coexistence of NO. However, its denitrification activity decreases rapidly and can not be regenerated effectively for the tests with SO2-O2-N2 and SO2-NO-O2 -N2 simulated flue gas. The characterization results indicate that both SO2 and NO can be adsorbed on the adsorbents, and the main reasons for the adsorbents deactivation are its porous channel plugging and surface property variation.