NOx removal from gas mixture intensified by rotating packed bed with NaClO2 preoxidation

Abstract Stricter emission standards of NOx from marine exhaust call for efficient NOx removal method. In this work, a wet denitration intensification method conducted in novel Cross-flow rotating packed bed (CFRPB) reactor was proposed to meet the confined space requirement. In the CFRPB, the enhancement of oxidation and absorption were simultaneously achieved during NOx removal process. The NaClO2 and Na2SO3 solution were employed as liquid oxidant and absorbent, respectively. NOx oxidation was intensified by Gas-phase disturbance internal (GPDI) and multilayer wire mesh internals. The oxidation degree (α) was increased by 1.7 times after internal optimization. NOx absorption process was intensified via the high-gravity environment created by rotating packing. Effects of various operation parameters on NOx oxidation and absorption were also investigated. α and NOx removal efficiency (η) can reach up to 92% and 84%, respectively. Compared with traditional scrubbers, CFRPB has higher value of volumetric mass-transfer coefficient, which displays great potential for NOx removal from marine exhaust.