Gas-liquid contacting devices

Typical Values. Table 11.3 shows typical parameter values for mechanically agitated tanks and other gas-liquid contacting devices. Not shown are values for kgAj since these are usually so large that they have no influence on the mass transfer rate. 

TABLE 11.3 Typical Operating Ranges for Gas-Liquid Contacting Devices... 

At the most basic level, the SDR is an extremely effective gas-liquid contacting device. This makes it ideal for performing many intensified heat or mass transfer operations and, as will be discussed later, it may be deployed as an evaporator or an aerator/desorber. However, its principal application in the process industry is likely to be as a very high-performance reactor. Since the reactor is the heart of... 

Finally it is interesting to learn, which values of the sorption characteristic Y the proposed gas/liquid contacting devices attain in comparison with gas bubbles of a particular size dt, which individually emerge from a borehole. This comparison is presented in Table 4.4 and shows that the bubbles in the swarm have a terminal bubble size of dt > 2 mm. A sorption number value achieved with the slot injector... 

Middleton, J. C., Motionless Mixers as Gas-Liquid Contacting Devices, AIChE 71 Aimual Meeting, Miami, 1978. 

Methods for estimating quantities of entrain meat from gas-liquid contacting devices are also scarce. Distillation tray correlations by Fair1 are useful for tray-contacling operations (Figs. 3.2-3 and 3.2-4). Csb, Rood is obtained from Fig, 3.2-3 die flooding velocity is calculated by... 

Figure 5. Aeration efficiencies of various gas-liquid contacting devices (air-electrolyte systems). Reproduced, with permission, from Ref. 38. Copyright 1981,...

Figure IS. I Gas-liquid contacting devices for low-viscosity systems...

The choice of a particular type of equipment for a given duty will depend upon many factors such as the scale of operation and required rate of mass transfer. A comparison of the operating characteristics of some gas-liquid contacting devices is presented in Table 15.1. 

Table 15.1 Comparison of different gas-liquid contacting devices... 

A general comparison of the properties, relative to other gas-liquid contact devices is given in Table 1.1, Section 1.6.1. 

Ehrig, R., Ofenloch, O., Schaber, K., and Deuflhard, P., Modelling and simulation of aerosol formation by heterogeneous nucleation in gas-liquid contact devices, Chem. Eng. Sci., 57, 1151-1163, 2002. 

Since the term is not relevant in the application of the ejector as a gas-liquid contacting device, Equation 8.2 was further simplified as... 

Computational Fluid Dynamic (CFD) and mechanistic models of gas-liquid flow and mass transfer at turbulent conditions are useful for studying local inhomogeneities and operation conditions of gas-liquid stirred tanks. They are applicable also as scale-up and design tools of gas-liquid stirred tank reactors and other gas-liquid contacting devices with greater confidence compared to purely heuristic design methods. Experiments are needed for the development and the verification of these models. 

Middleton, J. C. (1978). Motionless mixers as gas-liquid contacting devices. Paper 74e, presented at the AIChE Annual Meeting, Miami Beach, FL. 

Any of the gas-liquid contact devices described in Chap. 6 are applicable to the operations described here, and conventional packed and tray towers are very effective in these services. 

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