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• The flow and breakage processes of two liquid jets impacting on SSM were studied. • Compared with 2 θ = 30°, the values of d avg at 2 θ = 90° decreased by 32%. • The breakage mode at mesoscale is result of surface tension and inertia force. • Deviation of L s / D 0 between calculated and experimental values was within ± 15%. The flow and breakage behaviors of two liquid jets is of great importance for liquid–liquid mixing and reaction applications. However, the flow behaviors and breakage processes of two liquid jets impacting on the stainless steel wire mesh (SSM) is not clear. In this work, the high-speed photograph method was employed to study the behaviors of two liquid jets impacting on SSM. Effects of impinging angle (2 θ), liquid initial velocity (u 0), mesh number (M), and liquid jet diameter (D 0) on liquid flow and breakage behaviors were investigated. Experimental results showed that the jets of water-water impacting on the SSM were broken into liquid jets and further broken into daughter droplets. The cone angle of dispersion increased with the increase of 2 θ , u 0 , M , and D 0 , and reached the maximum value of 180°. The average diameter of daughter droplets at 2 θ = 90° decreased maximally by 32%, compared with the condition of 2 θ = 30°. For two liquid jets of water- n -hexane impacting on the SSM, a liquid sheet was formed. Under different operating conditions, the breakage mode of liquid sheet could be divided into marginal breakup and internal breakup. The breakage model at mesoscale is the result of surface tension and inertia force, both of which are relevant to the complex impact and flow behaviors. The liquid sheet length (L s) decreased with the increase of u 0 and M. A correlation to calculate L s / D 0 was proposed and the calculated results lied within ± 15% of the experimental values. This study provided a theoretical basis for the guidance of mass transfer enhancement and the reactor design with liquid–liquid system. [ABSTRACT FROM AUTHOR]

[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]