SU747477A1 - Mass exchange column - Google Patents

Description

one

The invention relates to the equipment for the testing of mass transfer processes between gas and zhitskoe. Especially the preferred area of application of the invention is the rectification under vacuum of thermally sensitive substances, for example lactams, heavy esters, and various oils of food and pharmaceutical products.

A film apparatus is known for carrying out mass transfer processes in a ж ikosta-gas system, comprising a housing in which a package of horizontal plates is installed. The gas passes in the gaps between., Horizontal plates, and the liquid flows from the plate to the plate through the holes at their ends l.

While gas and liquid are moving countercurrently on the same horizontal plate, gas and liquid are moving in the same direction on the adjacent top and bottom of the horizontal plates, i.e. directly. Therefore effectiveness

mass transfer in the apparatus is low. For example, when rectifying it is impossible to obtain several theoretical plates.

A known liquid-gas mass transfer column, comprising a body divided into internal compartments by horizontal partitions with openings, flanged plates mounted at a distance one above the other in the internal compartments in the vice irrigated packages with vertical central channels equipped with reflectors and co-located openings in horizontal partitions 2.

Horizontal partitions and reflectors provide a curvature of the trajectory of the gas flow and force it to cross the gaps between the flanged plates of the irrigated packages. At the same time the gas flow from the central channel of the irrigated package penetrates into the space surrounding the package. The content in the gas of a volatile component (during rectification) is the same in any

point of the central channel. In the gaps, the gas is in contact with the zhitskoi foam covering the flanged plates on top, and is enriched with easily volatile components by reducing its content in the liquid. This enrichment is the more significant, the higher is the gap in the irrigated bag, because the fresh portions of the liquid contain more of the easily volatile component than the liquid, which is already in contact with the gas. Least of all, the gas is enriched with a volatile component in the lowest level of the package, where it contacts with the liquid containing it in the smallest quantities. In the space surrounding the irrigated package, the upper and lower jets (layers) of gas are mixed and flow into the central channel of the overlying package, where the described process is repeated. Due to the fact that the lower gas jets contain less light-flying than the upper ones, they reduce the sparsened concentration of volatile gas in the gas stream leaving the irrigated package. Thus, the overall efficiency of the irrigated package is reduced.

The aim of the invention is to increase the efficiency of mass transfer by partially recirculating the gas stream.

This goal is achieved by the fact that, in the column, the partitions are provided with vertical nozzles installed in the openings, the internal cross section of which by area is 7О-9О% of the cross section of the vertical central channels located relative to the lower part of the irrigated packages packages and the underlying horizontal partitions have gaps, with a height exceeding the distance between the intersection plates 1.5-3 times.

FIG. 1 shows a mass transfer column, a longitudinal section in FIG. 2, section A-A in FIG. one.

The column contains a vertical cylindrical body 1 with nozzles 2 and 3 al of the gas inlet and outlet and with nozzles 4 and 5 for inlet and liquid outlet, with horizontal partitions 6. These barriers divide the working volume of the column into a number of internal compartments. In the latter, there are irrigated packs 7 of beaded plates 8, edges 9 of which are flanged upwards. The beaded plates 8 can be oriented either horizontally or obliquely. For example, they may be in the form of an ozone-positive helical surface, as shown. The flanged plates 8 are installed one above the other at a distance with a gap 1O so that inside the irrigated packages 7 there are free cavities in the form of vertical central channels 11. The latter are equipped with reflectors 12, which are designed to divert the gas flow into the gaps 10 between the flanged plates 8 irrigated packages 7.

Irrigated packages 7 are reinforced with a mixture of ribs 13 on horizontal partitions 6.

In the center of the horizontal partitions

6, re-representative cups 14 with drain nozzles 15 can be installed. Exactly the same cup 14 can be installed under the trimmed nozzle 4 for supplying liquid.

Vertical central channels 11 irrigated packages 7 are communicated through the holes 16 in the horizontal partitions 6 with the underlying internal compartments. Through the gaps 10 between the flanged plates 8, the vertical central channels 11 communicate with the space 17 surrounding the irrigated packages 7.

Between the irrigated packages 7 and the underlying horizontal partitions 6 free spaces 18 are left with a height exceeding 1.5-3 times the size of the gap 10 between the flanged plates 8. In the openings 16 of the horizontal partitions 6 there are vertical nozzles 19. The area of the internal cross section vertical nozzles. 19 represents 7O9O% of the cross-sectional area of the vertical central channels 11.

The vertical nozzles 19 form with the lower part of the irrigated packages 7 annular slots 20, the width of which in the narrowest place is not less than the size of the gap 10 between the flanged plates 8.

The mass transfer column operates as follows.

Liquid through pipe 4 enters the upper redistribution cup 14, from where it spreads in equal parts to all irrigated packages 7. From the packages

Claims (2)

7, the liquid flows to the horizontal partition 6 and is again collected in the redistribution cup 14. From the lowest partition, the liquid is discharged to the outside through the nozzle 5. The gas enters the column through the lower nozzle 2. Through the vertical nozzles 19, reinforced in a horizontal recess 6, the gas at high speed (in the case of vacuum rectification) rushes into the vertical central channels 11, and a certain amount of gas already in contact with the film of gas from the space 17 flows. From the vertical central channels 11 the gas passes through the gaps 10 into the space 17, from where through the vertical nozzles 19 enters the overlying inner compartment. Partial gas recirculation improves mass transfer efficiency in the column. The efficiency of the irrigated bag (as a separate contact stage) increases on average by 1.2 roses compared to the efficiency of the bag without recirculation. A liquid-gas mass transfer column comprising a vertical body divided into internal compartments by horizontal partitions with openings for the passage of gas; 11 20 Sch 9 9 18 / 7 bathtubs, spaced one above the cores in the inner compartments in the vice-irrigated packages with vertical central channels for the passage of gas, equipped with gas flow reflectors and spaced coaxially in the openings in the horizontal recessions, so that efficiency of mass transfer by partial recirculation of the gas flow; the partitions are provided with vertical nozzles installed in the openings, the cross section of which by area is 7-0-9% of the cross section neither the vertical central channels, and the lower part of the irrigated packages is located on the distance from the underlying horizontal partition, which is 1.5–3 times greater than the paccTOjf between the flanged plates. Sources of information taken into account during the examination 1. USSR author's certificate No. 250878, cl. In O1 D 3/30, 1970. 2. USSR author's certificate No. 399240, cl. At 01D 3/30, 1970. i7 Aa