SU904752A1 - Packing device for mass exchange apparatus - Google Patents

Description

() NOZZLOCHNY DEVICE FOR MASS EXCHANGE

one

The invention relates to designs for the interaction of gas (vapor) and liquid and can be used for heat and mass transfer processes in the food, pharmaceutical and chemical industries.

Devices for interaction of gas-liquid streams are known, which consist of a cylindrical body and a nozzle operating in emulsification mode.

However, they do not allow the creation of a stable emulsification regime, due to the need for a strict ratio of flow rates, which is not always ensured under the conditions of industrial apparatuses. Deviations from the regimes result in the release of the liquid phase or the breakdown of emulsification.

A nozzle column is known, including a cylindrical body inside which a nozzle is located, made of Raschig rings.

and distribution devices for the U1 liquid phase.

The design has a number of drawbacks. The column operates in the pure film mode, which reduces the intensity of the phase interaction. Emulsification is not used. At the interface of the device body with the nozzle, a bypass in the liquid phase occurs. The liquid phase is not evenly distributed throughout the entire nozzle. All this reduces the intensity of the heat and mass transfer processes.

The purpose of the invention is to create zones of stable emulsification along the height and uniform distribution of phases over the cross section of the apparatus.

Claims (2)

The goal is achieved by the fact that in the housing inside which the nozzle and the distribution device are located, the nozzle is made in the form of three periodically alternating layers, with the free section of the middle layer 390. the nozzle is 2-10 times the free section of the upper layer of the nozzle and the free section of the lower layer is 2-8 times smaller than the free section of the upper layer of the nozzle, and the distribution device is installed in the lower layer of the nozzle. The fluid distributor is made in the form of a vertical cylinder, plugged from the bottom end and provided with horizontal radial nozzles with perforations and vertical guiding plates. In addition, in the upper layer of the nozzle, at its periphery, flat horizontal rings are installed, which exclude the bypass at the interface between the casing of the column and the nozzle. FIG. 1 shows the proposed nozzle design 5 in FIG. 2 is a section along A-A of FIG. 1. The packing device consists of a cylindrical vertical body 1 inside which a nozzle is placed, made, for example, in the form of Raschig rings, consisting of 3 layers: the top layer of the nozzle 2, middle 3, bottom k. The free section of the upper layer is made smaller than the middle layer, and the lower one is smaller than the previous 2 due to the difference in the geometric dimensions of the bodies on the load. In the lower layer of the nozzle k there is a distribution device for the liquid phase, made in the form of a vertical cylinder 5, equipped with horizontal radial nozzles 6 with perforations and vertical guiding plates 7. The order of alternation of the layers of the nozzle in the lower part of the device is similar to that described above. The nozzle can be made not only from Raschig rings but also from various helixes, oak staves, etc. The proposed construction works as follows. The liquid phase is fed to the column from the top and flows through the top layer of the packing 2 in the form of a film. The interaction of liquid and vapor occurs in the film mode. Having reached the middle layer of the nozzle 3, the liquid is collapsed through it onto the lower layer 4, since in the layer 3 the free section of the nozzle is chosen from the condition that the fluid freely moves in the vertical 2 horizontal directions. The free section of the lower layer of the nozzle 4 provides such vapor flow rates at which the liquid is not able to flow through the low layer of the nozzle. Here, by increasing the reflux densities and gas velocity, an emulsification mode occurs. This mode is most effective, since the most intense interaction of the phases is observed, the maximum time and the surface of their contact. The emulsified layer of fluid fills, depending on the ratio of the flows, a determined volume of the middle layer of the nozzle 3 and flows into the vertical cylinder 5 of the distributor. In the latter, a column of liquid occurs, which ensures the overflow of the liquid phase through the pipes 6 and irrigation of the upper cut of the upper layer of the nozzle 2. The movement of liquid and vapor in the underlying nozzle is repeated. The process of mass exchange between the vapor and the liquid occurs wherever there is contact. The most intense mass exchange zone lies above the bottom layer of the nozzle 4 in the area where the emulsion mode occurs. Since the emulsification region occupies only the middle layer 3 and the lower part of the upper layer 2, and not the entire nozzle as in the analogs, it allows for some fluctuation of the vapor flow rate. If, for some reason, steam rates are allowed to increase under production conditions, the emulsification area will increase, but the flooding mode will not occur, since the upper layer of the nozzle 2 performs the function of a separator, and the liquid flows through the lower layer of the nozzle through the distributor . The supply of the cylinder 5 with vertical guide plates provides for the vertical installation of the cylinder, which is necessary for an even distribution of: fluid over the horizontal section of the device. I Installed in the upper layer of the nozzle 2 horizontal plates 8 exclude the bypass in the liquid phase. Experiments show that to ensure the order of movement of liquid and vapor described above, the free section of the middle layer 59 of the nozzle is 2-10 times more than the free layer of the upper layer of the nozzle, and the free section of the lower layer of the nozzle is 2-8 times smaller than the free sections of the top layer of the packing. Thus, the proposed design of the packing device for mass transfer devices allows creating a stable and effective emulsification mode. The device ensures uniform distribution of liquid phases di entire nozzle Due USE OF flat horizontal rings excluded bypass for the liquid phase in place of the coupling housing and n columns cages. The effect of introducing this design can be obtained by reducing the loss of recyclable materials, reducing the metal intensity of the apparatus and simplifying the operation of the device. Claim 1, A nozzle for mass exchangers, consisting of a vertical body, inside which is placed a nozzle, mainly Raschig rings, and a liquid distribution device, characterized in that, in order to create stable emulsification zones and uniform distribution of phases over the cross section of the apparatus, the nozzle is made in the form of three periodically alternating layers, while the free cross section of the middle layer of the nozzle is 2-10 times larger than its. the free section of the upper layer of the nozzle, the free section of the lower layer of the nozzle is 2-8 times smaller than the free section of the upper layer of the nozzle, and the distribution device is installed in the lower layer of the nozzle, 2. The device according to claim 1, wherein the fluid dispenser is made in the form of a vertical cylinder, plugged from the bottom end and provided with horizontal radial nozzles with perforations and vertical guiding plates. Sources of information taken into account during the examination 1, Kafarov V.V., Basics of Mass Transfer, 1972, p. 3 (prototype).