面向烟气NOx净化与回收的新型吸附工艺

合理高效的吸附工艺是决定吸附法净化和回收烟气中NO_x工业可行性的关键工艺环节。提出一种通过外部补充气体实现固定床循环体空间内多次循环解吸NO_x的新型吸附工艺（GVTSA）。基于该工艺，采用Na-ZSM-5分子筛作为吸附剂，以某钢厂烧结机脱硫后烟气为原料（组分）进行了NO_x吸附回收实验研究。结果表明，GVTSA工艺相较传统吸附工艺（TSA工艺、VSA工艺）可获取更高的NO_x回收量，在优选条件下（220℃，-50 kPa），NO_x回收率达到90%，解吸气中NO₂浓度由原料气的36 mg·m^-3提升到2%以上，NO_x循环吸附量可达0.10 mmol·g^-1，16次吸脱附循环稳定。研究结果可为烟气NO_x治理与资源化工业应用提供参考。

A new adsorption process for flue gas NOx purification and recovery

Reasonable and efficient adsorption process is the key process link that determines the industrial feasibility of the adsorption method to purify and recover NO_x in flue gas. In this paper, a novel adsorption process (GVTSA) with NO_x desorption using multiple hot gas circulations (GC) within the enclosed fixed bed through extra gas replenishment was proposed. Based on Na-ZSM-5 zeolites as sorbents, experimental studies on NO_x adsorption and recycling from desulfurized iron-ore sintering flue gas of a steel plant were conducted. The results show that the GVTSA obtained a higher NO_x recovery compared with traditional adsorption processes (e.g. TSA, VSA), reaching 90% under the optimal conditions (220℃, -50 kPa). The concentration of desorbed NO₂ was more than 2%, significantly enhanced from merely 36 mg·m^-3 in the feed gas. The NO_x cyclic adsorption capacity reached 0.10 mmol·g^-1 for up to 16 cycles. This work can provide references for industrial engineering application of flue gas ultra-low emission control and resource utilization.