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[Display omitted] • A cross-flow rotating packed bed for NO x oxidation and removal was developed. • Oxidation degree was increased by 1.7 times after internal optimization. • Cross-flow rotating packed bed intensified mass transfer between NO x and Na 2 SO 3. • Oxidation degree and removal efficiency can reach up to 92% and 84% respectively. Stricter emission standards of NO x from marine exhaust call for efficient NO x 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 NO x removal process. The NaClO 2 and Na 2 SO 3 solution were employed as liquid oxidant and absorbent, respectively. NO x 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. NO x absorption process was intensified via the high-gravity environment created by rotating packing. Effects of various operation parameters on NO x oxidation and absorption were also investigated. α and NO x 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 NO x removal from marine exhaust. [ABSTRACT FROM AUTHOR]

[Display omitted] • 3D multiphase CFD model of an RPB with wire mesh packing is developed. • Macroscopic and microscopic characteristics of the liquid flow are analysed. • Dynamic evolution processes of liquid droplet in the packing region are analysed. • The interfacial areas between different phases in the RPB are analysed. An in-depth understanding of the liquid flow characteristics in rotating packed beds (RPBs) is very important for the optimization and modelling of RPB reactors. However, the complex and dense packing makes it very difficult to accurately obtain the dynamic and detailed characteristics of liquid flow in RPBs through experimental methods. Therefore, this paper carried out a 3D gas–liquid flow CFD simulation of an RPB with structured wire mesh packing to obtain detailed liquid flow information. Detailed macro and micro characteristics of the liquid flow in the packing region of the RPB are obtained. The dynamic evolution processes of droplets are observed and analysed. A new flow pattern of "branch flow" is observed in the packing region. In addition, two typical liquid disintegration modes of liquid ligament-droplet disintegration and liquid bridge-droplet disintegration are observed, and the disintegration mechanisms are analysed. Finally, the effects of contact angle and rotational speed on the characteristic parameters are investigated, and the interfacial areas between different phases in the RPB are analysed. In both hydrophilic and hydrophobic packings, the wetted packing surface area is always less than the gas–liquid interfacial area, and their ratio decreases with the increases of contact angle and/or rotational speed, but increases with the increase of the liquid viscosity. [ABSTRACT FROM AUTHOR]