RU2379096C2 - Horizontal disc-shaped heat- and mass-transfer apparatus - Google Patents

Abstract

FIELD: production processes.

SUBSTANCE: invention refers to processes and apparatus of chemical machine industry and may be used in power, petroleum, chemical, food industry and other branches of industry. Apparatus contains cylindrical body with bottoms, in its upper part tubes for gas delivery and extraction are installed, and in its lower part - tubes for delivery and extraction of liquid. Apparatus is provided with circular baffles forming sections with external annular channels, longitudinal shaft and also with transverse solid and circular contact discs (CCD) installed on shaft in alignment to it, these discs are installed with clearance in relation to solid discs, shaft and each other and are partially submerged in liquid, and they form contact packages with central axial channels in them. Circular baffles are rigidly fixed in relation to each other and to body, at that solid contact discs are fixed on shaft together with circular contact discs and with installed between them opposite to circular baffles separatory contact discs forming together rotor of circular contact discs which is installed in body with minimal clearance in relation to surfaces of central holes of circular baffles. Side surfaces of circular contact discs, between which gas-vapor mixture (GVM) flows from central axial channels to external annular channels, are provided with corrugations which form profile of channels of centrifugal contact packages. Profile of corrugations on circular contact discs, along which flow of gas-vapor mixture is directed from external annular channels to central axial channels, is designed analogous to profile forming system of corrugations on contact discs of centrifugal contact packages, and circular contact discs are installed in rotor in such a way, with respect to circular contact discs of centrifugal contact packages, that they form centripetal contact packages.

EFFECT: structure of heat- and mass-transfer apparatus allows to provide high effectiveness of its production, assembling and disassembling, to increase operating characteristics and to improve process efficiency.

11 cl, 11 dwg

Description

The invention relates to processes and apparatuses of chemical engineering and can be used in the energy, oil and gas, chemical, food and other industries for wet gas purification, absorption, rectification (distillation), etc. processes in the gas-liquid system.

A device is widely known from the prior art for carrying out a heat and mass transfer process by contacting a gas stream with a liquid stream flowing on the surface of a liquid droplet or film in hollow (non-nozzle) plate (cascade), packed film columns (see A.N. Planovsky , P. I. Nikolayev. Processes and Apparatuses of Chemical and Petrochemical Technology. M., Chemistry, 1972, p. 322, 323, 329-331, 373). The intensity of heat and mass transfer is determined by the velocities of the gas and liquid flows and largely depends on the size and shape of the contacting surface, however, an increase (development) of the latter leads to an increase in hydraulic resistance, entrainment of liquid droplets, and complication of the design and dimensions of heat and mass transfer apparatuses.

Heat and mass transfer apparatuses (TMOA) are known containing a housing with a gas channel and nozzles for supplying and discharging gas, the lower part of which is filled with liquid, and a horizontal shaft installed in the housing with disks partially immersed in a liquid that is equipped with a drive for rotation (see Aut St. USSR 262096, class B01J 8/10, 1970; Aut. St. USSR 971437, class B01D 45/18, 1981) In this case, the implementation of disks in the form of grids or blades ensures axial gas flow with high enough speed, but does not allow to significantly develop on top contact phase.

Close to the invention is a mechanical film heat and mass transfer apparatus (see V. M. Ramm. Gas Absorption. M .: Chemistry 1976, pp. 321-322), containing a cylindrical body equipped with dividing annular partitions forming sections. In each section, a solid disk is fixed on the shaft, to each of which packets of ring contact disks are mounted on each side, installed with a gap relative to the housing, shaft and each other. In the upper part of the body there are pipes for supplying and discharging gas, and in the lower part there are pipes for supplying and discharging liquid. The shaft is equipped with a drive for rotation. The contact discs are partially immersed in liquid. Such a device apparatus forms a zigzag radial-axial gas duct in the upper part of the body, and a liquid duct in the lower part, which, in principle, makes it possible to use it effectively for heat and mass transfer processes that require extended contact of the gas with a liquid film.

However, in such devices, a contradiction arises between the efficiency of organizing the heat and mass transfer process and its constructive implementation.

So, from the point of view of increasing the efficiency of the process of heat and mass transfer, in devices of this type it is necessary to ensure minimum axial gaps between the extreme (in packages) ring contact disks and the dividing ring partitions that are not involved in the process of heat and mass transfer (since the latter are fixed (welded) in the housing and their surface is not wetted by liquid), i.e. the size of these gaps should be no more than the value of the optimal gaps between the annular contact disks. At the same time, from the point of view of ensuring the manufacturability and manufacture of such devices and their operation, as practice shows, when installing, as a rule, 10-16 separation ring partitions, part of these gaps is 1.5-2 times greater than the optimal gaps between ring contact disks, which in turn leads to the flow of part of the gas through these "technological" gaps, bypassing the mass transfer process on the contact disks and, as a result, to a decrease in the efficiency of these devices.

A significant drawback of such devices is their structural complexity, low manufacturability and assembly, caused by problems of high precision manufacturing of longitudinally split housings, installation and precise fixation of separation partitions relative to each other, and installation of a shaft with packages of annular contact disks (with predetermined axial clearances relative to separation partitions taking into account manufacturing and assembly errors), which leads to an increase in their dimensions, design mass and cost (by 60-200%) in flesh before losing their competitiveness.

Close to the present invention should include heat and mass transfer apparatus (prototype - RF patent No. 2200054, CL B01D 53/18, 47/18 of 12/19/01), containing a housing consisting of a cylindrical part of the housing and bottoms with, as at least one flange connection, in the upper part of which there are nozzles for supplying and discharging gas, and in the lower part - nozzles for supplying and discharging liquid, equipped with a set of dividing annular partitions installed between cylindrical inserts, fastened to each other on the inside of wok with longitudinal studs, fixed on one side in the extreme separation ring partition of the set, and on the other, in the flange of the housing, and forming sections, in each of which a solid disk is installed on the rotating shaft, on the sides of which are fixed packets of ring contact disks installed with a gap relative to the cylindrical inserts, the shaft, each other and the annular partition walls and forming contact packages that are partially immersed in the liquid and which together with the cylindrical inserts and the section -inflammatory annular partitions formed radially zigzag-axial, series-parallel flow of the gas stream through the flow of the apparatus.

This TMOA has all the above advantages inherent in horizontal disk heat and mass transfer devices (GDTMOA).

The disadvantages of this device, as practice has shown, are:

- low manufacturability and the complexity of manufacturing high-precision cylindrical inserts (in width and purity of the processing of the end surfaces) between the dividing ring partitions;

- the difficulty of combining and sealing holes in cylindrical inserts (bandages) with holes in the housing for supplying and selecting shared homogeneous liquid mixtures from the corresponding sections. This is due to the need to ensure double tight connection of the fittings both with the outer casing and with the holes in the cylindrical inserts (bandages) that form the inner walls of the sections, as a consequence of the difficulty of ensuring the alignment of these holes during their assembly (bulkhead).

In addition, the presence of stagnant zones between the main body and the inner case, formed by the protruding parts of the separation ring partitions relative to the cylindrical inserts and bandages, creates problems in the production of highly pure components or food products, and when combined, it leads to a limitation of their application, lower performance devices, the manufacturability of their manufacture and the increase in the value of GDTMAA.

The disadvantages of this scheme are the lack of objective control of the gaps between the extreme disks of the contact packets and the separation ring partitions during their assembly, since the bandages block access for instrumental measurement of the gaps after tightening the studs. This circumstance required the introduction of technological bandages with “windows” for pre-assembly with instrumental control, since ensuring a guaranteed clearance is necessary when operating these devices in explosive atmospheres, in order to exclude the possibility of sparking when rotating disks come in contact with stationary annular partition walls.

Closest to the invention is a heat and mass transfer apparatus (see RF patent No. 2152245, class C1, dated July 10, 2000), containing a cylindrical body, in the upper part of which there are pipes for supplying and discharging gas, and in the bottom - pipes for supply and drainage of liquid. The apparatus is equipped with a rotating shaft with coaxially mounted transverse solid disks and dividing ring partitions sequentially mounted on it coaxially with the body and shaft with gas-dynamic, hydrodynamic or contact seals installed on their outer diameter. Between the continuous contact disks and the separation walls, coaxial contact packages (CP) are installed, consisting of annular contact disks installed with a gap relative to the housing, shaft and each other and partially immersed in the liquid and which together form a zigzag radial-axial, sequentially parallel flow gas and liquid flows. A shaft with solid contact disks, dividing walls and contact disks form a rotor of contact disks. In this case, the process of heat and mass transfer is carried out during the contact interaction of the gas stream with a liquid film that forms on the surface of the rotating disks under the conditions of a continuous flow of the liquid film.

This device allows you to increase the surface of the effective contact interaction of gas with a liquid film (due to rotation and dividing annular partitions), provides the ability to organize more intense processes of heat and mass transfer and, as a result, significantly higher efficiency of various processes of heat and mass transfer in a wide range of combination of operating parameters and thermophysical properties of interacting media (gas and liquid), with a continuous flow of a liquid film (absorption, rectification, gas purification) in horizontal devices with rotating disks. In addition, this design of the apparatus provides the smallest overall and mass characteristics with high manufacturability and the lowest cost in comparison with other known devices of this class.

At the same time, as experience in the creation and operation of installations for this patent has shown, these installations have a number of disadvantages, which include:

a) a limited specific consumption for the absorbent, since with an increase in the rotational speed of the KP, the flow of absorbent through the apparatus decreases, which imposes restrictions on the rotational speed of the KP (to -40-50 rpm);

b) an increase in hydraulic resistance along the working path (up to 80-140 mm water column) with an increase in the rotational speed of the gearbox, which is undesirable with respect to systems for trapping vapors of low-boiling fractions on gasoline transshipment racks, etc .;

d) in the manufacture of high-capacity devices (with diameters of more than 400 mm), difficulties arise in ensuring the required accuracy of manufacturing the cylindrical part of the housing due to the difficulty of eliminating the ellipse of thin-walled housings and ensuring their alignment with the bearing block (for installing a shaft with contact bags), which automatically leads or to increase the gaps between the housing and the labyrinth seals along the outer diameter of the annular partition walls and, as a result, reduce the efficiency of these devices roystv or to increase body weight by increasing its thickness (processing allowance), and, accordingly, an increase in its weight, which is highly undesirable in the production plants of large diameter of the expensive stainless steels. In addition, the processing of the inner surface of large diameter casings and lengths requires special, expensive equipment.

Considering that at present at the enterprises of chemical engineering, food and other industries up to 60% of heat and mass transfer equipment has exhausted its life and that only 0.5% of nuclear power plants and oil depots, etc. equipped with hydrocarbon vapor recovery systems, as well as the fact that the “niche” at the medium and low productivity solid-state air mass media is practically empty, the relevance of creating high-performance compact plants of this class becomes obvious.

The present invention is directed to the creation of a more efficient, cheap and compact horizontal disk heat and mass transfer apparatus for solving, primarily, the problems of absorption, desorption, concentration and mass transfer, providing a uniform and more intense flow of heat and mass transfer on all CDs with simultaneous pumping of ASG along the working path of the GDTMOA with an increase in the efficiency (Efficiency) of contact disks, reduction of losses due to overflow of ASG along the “technological” gaps, bypassing the mass transfer process to ontact disks, and is also aimed at reducing the thickness and weight of the housing and structural elements of the GDTMOA, increasing the manufacturability of manufacturing and reducing the assembly time of the GDTMOA.

The solution to this problem is provided by the fact that in a horizontal disk heat and mass transfer apparatus (GDTMOA) containing a cylindrical body, in the upper part of which there are pipes for supplying and discharging gas, and in the lower part there are pipes for supplying and discharging liquid, equipped with dividing ring partitions forming sections with external annular channels, a longitudinal shaft mounted for rotation in bearing blocks with seals in the ends of the housing, as well as mounted on the shaft and transverse to it solid and annular contact disks, which are installed with a gap relative to the solid disks, the shaft and each other and partially immersed in the liquid, which form contact packages with central axial channels, according to the invention, the separation ring partitions are rigidly fixed relative to each other and the housing by spacer tubes installed on the longitudinal studs that are fixed in the housing, while the solid contact disks are mounted on the shaft together with the contact disks and installed between opposite the dividing annular partitions, they have dividing contact disks, which together form the rotor of the contact disks, which is installed in the housing coaxially with the dividing annular partitions with a minimum clearance relative to the surfaces of their central holes, while corrugations are made on the lateral surfaces of the contact disks, and the corrugations made on the contact disks between which the ASG flows from the central axial channels to the outer annular channels, form a channel profile of the ASG flow between K Similar profile channels of the centrifugal pump and the centrifugal contact KD form packages, the continuous, annular contact disks and spacer together with dividing septa ring and the housing are formed zigzag, radial-axial, series-parallel flow of the gas and liquid flows.

The claimed constructive implementation of heat and mass transfer apparatuses, in comparison with the prototype, allows you to:

- to reduce the flow of gas and liquid along the “technological” gaps between the sections: by a gap between the housing and the separation ring partitions by 3–5 times and by 2-3 times the gap between the separation contact disks of the rotor and the separation ring partitions;

- ensure the simultaneous processes of heat and mass transfer on all CDs with simultaneous (forced) centrifugal pumping of ASG along the working path of the GDTMOA (with an increase in the efficiency (Efficiency) of contact elements, i.e. contact disks);

- dramatically simplify the manufacturing and assembly technology of the rotor of contact bags and the entire TMOA;

- to reduce the mass and cost of TMOA by 10-20%, and the time of their manufacture - by 30-40%.

It is advisable that the corrugations on the CD be discontinuous, while the distance (L) between the corrugations forming the profiles of the ASG flow channels between the CD should not exceed 3 times the gap (N) between the CD.

The implementation of the corrugations as discontinuous or in the form of a system of cells allows us to achieve optimal turbulence of the ASG flow, to provide the required capture (rise) of liquid on the contact disks (without “choking” the sections of the ASG flow channels) at a given rotor speed and, thus, to ensure maximum heat intensity of the processes - and mass transfer on contact disks (and their efficiency) without a significant decrease in the efficiency of centrifugal packages, as low-pressure fans for pumping ASG.

It is advisable that the corrugation profile (system) on the CD along which the ASG flow is directed from the external annular channels to the central axial channels be performed similarly to the profile formed by the corrugation system on the contact disks of the centrifugal contact packets, and the contact disks themselves should be installed in the rotor with the reverse side to the centrifugal KP.

The execution of the corrugation profile (system) on the CD along which the ASG flow from the external annular channels to the central axial channels is carried out, similar to the profile of the corrugation system on the contact disks forming centrifugal contact packets, with the contact disks in the rotor being installed with the reverse side in relation to the centrifugal gearbox to increase the intensity of heat and mass transfer processes on these CDs with an increase in the effect of pumping ASG along the working path of the GDTMOA due to the (forced) pushing of the captured P by corrugations (analogs of the blades) With interdisk region of the central axial bore, particularly in the area of corrugations KD immersion in liquid. Contact disks with such a corrugation system form centripetal contact packets.

It is advisable that more than 70% of the corrugations on adjacent CDs in each contact package are equidistant.

Performing more than 70% of the corrugations at equidistant CDs allows us to achieve optimal ASG turbulence without a significant increase in hydraulic resistance between the CDs while maintaining the efficiency of centrifugal bags as low-pressure fans for pumping ASGs, and use the minimum number of dies (from two) for the manufacture of all corrugations on the CDs.

It is advisable that the height of the corrugations was not more than half the size of the gap between the contact disks, and the width (diameter) of the base of the corrugations was not more than 2 times the size of the gap (H) between the CD.

The implementation of the corrugations with geometric characteristics not exceeding the indicated relative sizes, allows you to avoid (when rotating the CD) excessive fluid capture, “flooding” and droplet transfer modes with satisfactory performance for pumping ASG along the working path.

It is advisable that the height of the corrugations, their width (diameter) and their number on the contact disks of the packages through which the CBC flows from the external annular channels to the central axial channels, be less (than) than on the CD of centrifugal packages.

This is explained by the fact that the ASG pressure obtained on centrifugal bags and their efficiency as pumping systems for ASGs (analogues of a system of sequentially installed low-pressure fans - liquid ring pumps) are significantly higher than on (centripetal) bags through which ASG flows from external ring channels to the central axial channels. In this regard, the role of the corrugations on them is reduced mainly to the function of increasing the turbulence of the ASG flow and increasing the liquid entrainment and, simultaneously, as the ASG pumping system, which makes it possible to compensate the hydraulic resistance of the ASG along the working path during rotor rotation and, accordingly, reduce energy the cost of its rotation by 15-25%.

It is advisable to install vanes of the guide apparatus on the spacer tubes between the dividing annular partitions in the sections.

The installation of guide vanes on spacer tubes in sections between the dividing annular partitions allows us to solve the following problems:

- in the fluid channel - to block the tangential swirl of fluid in the sections, leading to a sharp decrease in the axial flow of fluid (absorbent) along the apparatus and, thereby, if necessary, increase the flow rate of absorbent through the apparatus. At the same time, due to the formation of a wave from an inhibited flow, the wetting surface of the disks increases, and at the outlet of the disks from the liquid, the excess removal of droplets from the CD surface is blocked at high rotational speeds of the disks (about 70-100 rpm);

- in the external annular gas channel, the blades perform the function of a guide vanes, which can consist of 2-6 blades installed mainly in the zone of immersion of the disks in the liquid channel (during their rotation) and designed to reduce the pressure loss of the ASG at the entrance to the gaps ( centripetal) contact packages.

It is advisable to install additional dividing semicircular partitions opposite to each continuous contact disk in GDTMOA, in the part of the liquid channel of the housing.

The installation of additional dividing semicircular partitions in the GDTMOA opposite each continuous contact disk allows a 2-fold increase in the number of sections (separation stages - plate analogs in vertical TMAA) and to provide a higher degree of separation of components with a shorter GDTMAA length.

It is advisable to install solid disks, contact disks and separation contact disks in the horizontal disk heat and mass transfer apparatus with a gap relative to each other using spacers installed between the contact disks on the longitudinal spokes.

This design solution provides high rigidity of the rotor, the manufacturability of the manufacture and assembly of the rotor KP through the use of standard calibrated rods and cheap washers of the required range, commercially available from industry; allows to increase the length of the rotor, i.e. increase the number of sections in one block GDTMOA.

It is advisable to make gaps between the solid disks, contact disks, and separation ring disks due to the emphasis on the corrugations symmetrically made on the CD, and to provide a rigid connection between each other by tightening the CD between themselves using longitudinal knitting needles.

Such a constructive solution in non-essential products (for example, in absorbers for purifying air, flue gases or trapping ammonia from PVA) provides the ability to refuse spacers, reduce the mass of the rotor of the gearbox and its cost, and dramatically reduce the time it takes to assemble it.

It is advisable during the absorption process in the lower part of the separation discs and additional dividing semicircular partitions to make holes for the duct of the absorbent, and on the spacer tubes between the dividing ring partitions in the sections in the liquid channel to install the vanes of the guide apparatus.

This design solution provides 2-10 times greater absorbent throughput through the GDTMOA liquid path, which allows to achieve a higher degree of capture of various vapors and gases from ASG in the absorption blocks without increasing their dimensions.

Thus, the totality of the proposed technical solutions makes it possible to provide a more uniform heat and mass transfer process along the entire length of the rotor during contact interaction of the gas with the liquid film (by ensuring the same gaps between all CDs, reducing losses from the flow of media between sections and due to the introduction of corrugation), to increase the surface of effective contact interaction of phases (by ensuring the formation of a liquid film on rotating spinning discs), simultaneous pumping of ASG by GDTMOA working path (due to the introduction of a system of sequentially installed centrifugal and centripetal contact packages) while increasing the efficiency (COP) of contact elements (contact disks) and, accordingly, the efficiency of various heat and mass transfer processes in a wide range of combination of operating parameters and thermal properties of interacting wednesday At the same time, high manufacturability of the manufacture and assembly of the rotor and the entire GDTMOA is achieved.

GDTMOA data can be used in technological schemes with various liquid and gaseous substances, for example, during separation of components (rectification), mass transfer, gas purification, absorption of hydrocarbon vapors (phenol, formaldehyde, gasoline, etc.) from steam-air mixtures, instead bulky vertical columns with high hydraulic resistance, the release of "fatty" gases from associated petroleum gases, etc.

Schematic diagram and design features GDTMOA shown in the drawings. Figure 1 schematically shows a General view of GDTMAA. Figure 2 presents the cross section GDTMAA (AA, figure 1) with a view of the dividing ring partition with tightening pins and a contact disk with pulling spokes. Figure 3 schematically shows a fragment of a longitudinal section of the GDTMAA with a view (B, in Figure 1) on a CD with spacer washers and a tightening spoke, dividing ring partitions with a pulling longitudinal pin with a spacer sleeve mounted on it and a guide blade fixed to it. Figure 4 schematically shows the rotor of the contact packages installed in the removable bottom (a) and the housing ГДТМОА (b) in the vertical position for assembly, as well as the cross section С-С and Д-Д of the rotor and the housing. Figures 5 and 6 show cross-sections B-B and MJ GDTMAA (see Fig. 1) in versions with continuous corrugations on the CD (Fig. 5) and intermittent corrugations (Fig. 6) in the embodiment with guide vanes. In Fig. 7 (view E in Fig. 1), diagrams of the corrugations on the CD and the formation of gaps are schematically presented due to the emphasis on symmetrically made corrugations (option 1), one-sided corrugations (option 2) and spacers (var. 3) . On Fig presents cross-sections BB and MJ GDTMOA (see figure 1) in the variant with discontinuous corrugations and in the form of a system of cells, as well as installation options for guide vanes in the liquid channel and around the perimeter of the annular channel. Figure 9 schematically presents options (fragments) of longitudinal sections (G-D in figure 1 by KP) of the corrugation design on CD and options for contact packages. Figure 10 schematically shows a variant (a fragment of a longitudinal section (EE in Fig. 8 in terms of KP) performed by cellular corrugations on a CD and a variant of contact packets). Figure 11 shows the dependence of the efficiency η of the contact element on the fraction of gas bypass D _p between the gaps between the sections.

The horizontal disk heat and mass transfer apparatus (see FIGS. 1-10) contains a cylindrical housing 1, in the upper part of which there are pipes for supplying 2 and gas 3, and in the bottom - pipes 4 and 5, respectively, for supplying and removing liquid, and is equipped with dividing annular partitions 6, forming sections 7, and a removable bottom 8, in which the horizontal shaft 9 is mounted rotatably with transverse solid disks 10 fixed thereon by means of, for example, spacer sleeves 11. Between solid contact disks (C D) 10 are rigidly fixed by means of tightening knitting needles 12 and spacer washers 13 (see figure 2) contact disks (CD) 14 and separation discs (RD) 15, which together with the shaft form a rotor of contact disks (RKD) 16. KD 14 can be made, for example, smooth, rough, corrugated, perforated, ribbed, mesh, etc.

The dividing annular partitions 6 are rigidly fixed relative to each other and the housing 1 by spacer tubes 17 mounted on the longitudinal studs 18, which are fixed, for example, in the flange 19 of the housing 1.

The rotor of the contact disks 16 is mounted to rotate in bearing blocks with seals 20 in the removable bottom 8 and the (elliptical) bottom 22 of the housing coaxially with the dividing annular partitions with a minimum clearance relative to the surfaces of their central holes.

Each continuous contact disk (ACS) 10 together with the separation disk (RD) 15 and the contact disks (CD) 14 installed between them form contact packets 23 (Fig. 3) with axial channels 24 and slotted inter-disk gaps, which together with external ring channels 25, formed by the dividing annular partitions 6, form a longitudinal, relative to the shaft 9, flow channel (see figure 1).

The upper part of the flow channel together with nozzles 2 and 3 (for supplying and discharging gas), external annular channels 25, transverse solid disks 10, gaps between the annular contact disks 14, spacer disks 15 and axial channels 24 form a gas flow channel forming a multi-way zigzag radial-axial, sequentially parallel flow of gas flow. Similarly, in the lower part of the housing filled with liquid, together with the inlet and outlet pipes 4 and 5, a liquid flow channel 26 is formed. The rotation of the shaft 9 of the rotor of the contact disks 16 is provided by a drive (not shown) through a pulley or sprocket 27.

To ensure forced pumping of ASG through the gas flow channel 25 and to increase the turbulence of the gas flow in the gaps between the CDs, corrugations 28 are made on the lateral surfaces of the contact disks (see FIGS. 5-10). At the same time, the corrugations made on the contact disks through which the ASG flows from the central axial channels 24 to the external annular channels 25 form the channel profile of the ASG flow between the KD 14, similar to the channel profile of the centrifugal pumps, and these KD form centrifugal contact packets 29. The corrugations can be continuous 28 (Fig. 5), discontinuous 30 (Fig. 6) or a view of a system of cells 31 (Fig. 8), etc.

The formation of gaps between the CD can be carried out due to the stop in symmetrically made corrugations (see Fig. 7, option 1), due to one-sided corrugations (see Fig. 7, option 2) or spacers (see Fig. 7, var. 3).

Depending on the ratio of the width (diameter) of the corrugations of their bottom part (d) to the width (diameter) (D) at their base, i.e. d / D, the liquid capture by the corrugations during the rotation of the contact disks and the turbulence of the ASG flow change. As the d / D ratio increases, fluid uptake increases. The optimal d / D ratio is such that the angle φ (see Fig. 7) is φ = 15-35 ° (depends on the rotational speed of the rotor KD).

In an embodiment for carrying out the rectification (separation) processes of components, part of the sections of the GDTOA is equipped with temperature sensors 32, nozzles for selecting components 33 with electrovalves 34 for selecting components.

In order to block the tangential swirl of fluid in the sections, leading to a decrease in the axial flow of fluid (absorbent) along the apparatus, it is advisable to install the blades 35 of the guide apparatus on the spacer tubes 17 in the sections (in the fluid channel) between the dividing annular partitions. This allows, if necessary, to increase the consumption of absorbent 5-10 times (including through additional openings 41 for the flow of absorbent in the dividing ring partitions 6 and semicircular partitions 36). At the same time, due to the formation of a wave from a blocked flow, to increase the wetting surface of the disks, and at the outlet of the disks from the liquid, to block the excess removal of droplets from the CD surface (at CD rotation frequencies of about 70-100 rpm); in the external annular gas channel, the blade apparatus 35 is designed to reduce the pressure loss of the ASG at the external input to the rotor of the gearbox.

The installation of additional dividing semicircular partitions 36 of the liquid channel 26 in the GDTMA opposite each continuous contact disk allows a 2-fold increase in the number of sections (separation steps — plate analogs in vertical TMAAs) and to provide a higher degree of separation of the components with a shorter GDMAA length.

The introduction of the inner (relative to the diameter of the casing) flange 19 with a seal 39 and bolt fastening 40 allows to reduce the casing diameter and its mass by 8%.

The process of heat and mass transfer (in the absorption variant) is as follows. The vapor-gas mixture (PGS) flow enters the gas channel through the pipe 2, passes through the gaps between the CD 14 and the disks 10 and 15 of the first (along the PGS) packet 23, coming into contact with the film of liquid (absorbent) draining from the surface of the rotating disks 14, 10 and 15, which during rotation are partially immersed in a wetting liquid from the liquid flow channel 26. Next, the ASG along the axial channel 24 is deployed and passes into the radial gaps of the next (centrifugal) contact packet 29 (where the process repeats), into the outer annular passage 25, rotated 180 ° and moves in radial gaps between the CD package of the third contact, etc. before it leaves the device through the pipe 3.

In this case, the contact interaction of the phases occurs with a radial gas flow, which, flowing along the apparatus as a whole in the axial direction, with a sequential transition from the cavities of one packet of radial gaps - the axial channel 24, through the cavity (the gaps of the next packet, along the gas flow) section 7 into the outer annular channel 25, changes its (radial) direction of movement to the opposite, flowing around the contact elements (rotating disks 10, 14, 15) on both sides with a speed of W _g , i.e. within the limits of the gas channel, makes a multi-way, zigzag radial-axial, sequentially parallel movement.

The continuous flow of a liquid film over the surface of rotating disks 10, 14, 15, with corrugations 28 is ensured by limiting the maximum gas flow rate (W _g ) and selecting the disk rotation frequency (ω), which, in combination with the implementation of the centrifugal separating effect due to the rotation of the gas flow, eliminates the possibility of droplet-dropping, leads to a decrease in the dimensions of the apparatus, since this eliminates the need to create a significant separation space. In addition, the introduction of corrugations 28 makes it possible to increase the turbulence of the (gas) flow and increase the capture of CD liquid by a factor of 1.5-3 and, thereby, significantly increase the efficiency of heat and mass transfer processes in the zone of contact interaction of phases.

Installation of dividing ring partitions in the housing on longitudinal studs with their rigid fastening relative to each other and the housing flange with spacer tubes, with a minimum clearance relative to the housing (tight fit) and a clearance of 0.5-1.5 mm relative to the rotating rotor, while decreasing by 1 / 3 of the diameter of the sealing surface, allows not only 2-3 times to reduce the flow of liquid and ASG between the sections, but also to simplify the design of the heat-mass transfer apparatus, to ensure high manufacturability of assembly and times device bores, increase their operational characteristics.

The introduction of centrifugal 29 (and centripetal 38) gearboxes (see Figs. 9, 10) made it possible, at a minimum, to equalize the pressure at the boundary of the separation ring partitions (P _n ≤P _{n + 1} ) between the sections (see Fig. 10) and , thereby further reducing or eliminating the flow of ASG between sections. In a properly designed GDTMOA according to this scheme, a slight overflow of ASG between the sections (taking into account, for example, the absorption of part of the VFD) is possible in the opposite direction (against the flow), and not vice versa.

As an example. During the experimental development of the absorption block (based on GDTMOA with centrifugal gearboxes according to the schemes shown in Figs. 8 and 9) with the following parameters:

- PVA productivity of 50-60 m ³ / h;

- surface KD 42 m ² ;

- rotational speed of the rotor KD 30-90 rpm;

- outer diameter KD 390 mm;

- the inner diameter of the holes in the CD 160 mm;

- the number of centrifugal contact packages 12;

- a total of 24 contact packets (the number of CDs in the packets decreased from the condition of providing close to the optimal speed of the ASG flow along the GDTMOA working path);

- the height of the corrugations, made in the form of a system of cells on the CD, 1.7 mm;

- electric drive power for rotation of the rotor KD 0.36-0.5 kW,

it was found that on the contact disks in the form of a film there were constantly about 3.5-6 liters of absorbent material (depending on the temperature of the absorbent — chilled diesel fuel, which was T _ab = 0 - -5 ° С). To capture 95-98.5% of gasoline vapors from PVA, the required absorbent flow rate at the maximum mode was at least 600 l / h. At the same time, this amount of absorbent during this time (1 hour) was supplied to the contact zone on the surfaces of rotating CDs in a volume of 10,000 to 18,000 l / h, which is equivalent to the introduction of recirculation lines for each section (with 15-30-fold liquid recirculation ( !)).

The rate of ASG displacement from the gaps between the CDs, when immersed in absorbent material, even at minimum conditions in terms of ASG consumption, was from 0.4 to 1.8 m / s. The pumping of ASG through the absorption unit, due to the introduction of a multistage centrifugal contact bag system (without an injection system at the inlet), amounted to 30-35 m ³ / h. The hydraulic resistance along the working path at maximum mode (50 m ³ / h) decreased to 20-30 mm of water. Art. These effects are extremely important when conducting various processes of heat and mass transfer and provide high stability of the processes in a wide range of load changes.

If necessary, depending on the type of process and its required efficiency, seals 9 can be performed hydrodynamic, gasdynamic, or combined, for example, labyrinth 37 (see Fig. 10), which practically does not increase the electric drive power for rotating the KD 16 rotor.

We give evidence that the installation of dividing annular partitions with the simplest (labyrinth) seals leads to a decrease in the share of bypass and an increase in the efficiency of the apparatus.

The pressure drop between adjacent sections is equal to: Δp = P ₁ -P ₂

,

,

where: Σξ _K is the sum of the hydraulic resistance of the channel;

ℓ _K is the length of the channel;

λ _TP is the coefficient of friction;

d _EC - equivalent diameter of the channel;

W _K is the gas velocity in the channel;

p _G is the density of the gas.

V = ω _K · f _K , where V is the volumetric gas flow in the channel;

f _K is the cross-sectional area of the channel (between the disks 10, 14, 15, i.e. the cross-sectional area of the channel KP).

;

;

;

;

V _P = F _P · ω _P ,

where: ξ _P - coefficient of hydraulic resistance of the bypass channel,

ω _P - gas velocity in the bypass,

V _P - volumetric gas flow in the bypass channel.

The proportion of bypass (D _P ) of gas between sections along the gap Δ (bypass channel, Δ = 1-1.5 mm) in the (labyrinth) seal is determined as follows:

;

;

The figure 11 shows the relationship between the coefficient of efficiency of the contact stage (package of contact disks) and the proportion of gas bypass gap (axial or radial) between adjacent sections of the heat and mass transfer apparatus.

From the graph (Fig. 11) it can be seen that with an increase in the percentage of bypass D _{P, the} efficiency of the contact elements decreases and when D _P = 10-20%, it reduces the efficiency of these devices to 0.6 ÷ 0.55.

In analogs, due to the spread in the accuracy of manufacturing parts, assembly errors, axial clearances between dividing ring partitions and ring contact disks, as a rule, exceed the values of optimal working clearances between ring contact disks by 2-3 times, which leads to an increase in the percentage of bypass D _P to 10-15%, leads to a decrease in the efficiency η of contact elements from 0.7 to 0.55-0.6.

In the prototype, when creating high-performance devices (with a case diameter from 400 mm and above), problems arise with eliminating the ellipse of the cylindrical part of the case and the alignment of the rotor installation. The solution to these problems is connected with the boring of the case, which requires an allowance for processing (up to 4-5 mm) and the use of expensive equipment, which is the main reason that impedes their production.

In the transition to the proposed apparatus with dividing ring partitions installed in the housing (and not on the shaft, as in the prototype), the need for additional processing of the Central holes in the dividing ring partitions in most cases generally disappears.

и восстановить η от 0,55 до 0,67-,69.With gaps of 0.5-1.5 mm relative to the rotating rotor, a simultaneous decrease of 1/3 of the diameter of the sealing surface and the pressure drop between sections in 1-3 mm of water. Art., this technical solution (even without the use of labyrinth seals) allows 2-3 times to reduce the value

and restore η from 0.55 to 0.67-, 69.

It is obvious that when installing contact seals, the proportion of bypass D _P will be close to zero, i.e. the efficiency η of the contact elements (packets) will be close to the maximum possible ~ 0.7.

(It should be noted that the presence of movable, rotating together with the shaft of the separation ring partitions with a seal on their outer diameter, as in the prototype, does not always allow to achieve the required (especially high) purity of the dispersed fractions due to their partial flow of the separated substances between sections in the separation zones ring partitions).

The main advantages of this type of apparatus are:

- less loss on overflow of ASG;

- high manufacturability of manufacturing and assembly (disassembly) of the body and rotor of the GDTMOA for high productivity;

- the efficiency of heat and mass transfer processes and ease of operation of the apparatus;

- higher (up to 10%) device performance (with the same case diameter) due to increased efficiency (η) of contact packages;

- the possibility of direct selection (input) of products from any section of GDTMOA and the introduction of inspection windows for visual control of the process;

- eliminate stagnant zones in the cavity of the apparatus (which was typical for analogues) and helps to expand the scope of application of the apparatus;

- acceptable conditions for repeated washing and sterilization of devices.

Compared with other devices of the "vertical" type for a similar purpose, in this device, while maintaining the continuity of the process, as in packed columns, there are no "bypass effects" and there is no "flooding" of the CP and drip transfer. The constant restoration and replacement of the liquid film on CD during the rotation of disks partially immersed in liquid (phlegm) makes it possible to compensate for the erosion of the phlegm film on the surface of contact disks at high vapor phase flow velocities (from 1.5 to 3.5 m / s, depending from the viscosity of phlegmy and the diameter of the CD).

In the distillation options GDTMOA, reflux continuously flows from section to section (from the side of the reflux condenser), constantly present in each section, as in plate columns, providing phase equilibrium for all contact packets (in each section) during the entire period of operation, which allows continuously select highly enriched distillate of constant composition from the corresponding sections of the apparatus.

The key advantages of this type of apparatus are:

- 2-3.5 times greater (than in existing plate and packed columns) heat and mass transfer coefficients in the conditions of continuous flow of a liquid film with continuous contact interaction of a gas stream with a liquid stream flowing in the form of a film on the surface of rotating disks (during countercurrent flow of liquid and gas), which provides 5-10 times smaller dimensions of TMOA. At the same time, the height of the theoretical separation stage is built not in the axial, but in the radial direction. The latter circumstance allows us to ensure the smallest "height" (in this case, length) of the column;

- high efficiency of heat and mass transfer processes in each section of the apparatus (as a result of increasing the turbulence of the gas stream, a constant and sufficient mass of liquid on the CD and in each section (as in plate columns);

- the possibility of implementing forced pumping of ASG by centrifugal gearboxes, which, in combination with a sufficient accumulating heat capacity of rotating contact disks constantly immersed in liquid, provides (for each contact package) constant movement of ASG along the working path and the constancy of the surface temperature of the contact disks and, therefore, high stability of evaporation processes - condensation along the surface of the contact disks in each section;

- extremely low sensitivity to load changes and the possibility of a significantly wider range of control parameters GDTMOA (compared with the vertical counterparts TMOA) as due to changes in input and output parameters, including temperature and flow rate of input and output steam, accelerated liquid and distillate (reflux), so and by changing the rotor speed of the contact discs;

- a high degree of separation of mixtures with minimal energy costs and minimum dimensions of the apparatus (columns).

In addition, this apparatus has qualitatively new capabilities in the process of vacuum distillation, distillation, concentration, etc., which is associated with both low intrinsic hydraulic resistance (20-80 mm water column) and the implementation of a new property - pushing ASG along the working path of the apparatus during the rotation of the rotor due to the introduction of a corrugation system on the CD, i.e. implementation of the functions of a centrifugal low-pressure fan and a liquid ring pump built into the GDTMOA.

In general, this unit is significantly more technologically advanced than previous analogues, has higher efficiency, smaller dimensions, weight and cost, as well as all the advantages of disk, nozzle, film and disk devices (without inheriting their disadvantages). At the same time, new design solutions for the contact disk rotor, dividing partitions and the housing of the proposed apparatus provide compensation for the hydraulic resistance of the ASG along the working path, low sensitivity to load changes, and other advantages.

Claims (11)

1. A horizontal disk heat and mass transfer apparatus comprising a cylindrical body with bottoms, in the upper part of which there are nozzles for supplying and discharging gas, and in the lower part, nozzles for supplying and discharging liquid, equipped with dividing annular partitions forming sections with external annular channels , a longitudinal shaft mounted for rotation in bearing blocks with seals in the housing bottoms, as well as mounted on the shaft and transverse solid and ring contact disks aligned with it (K KD), which are installed with a gap relative to the solid disks, the shaft and each other and are partially immersed in the liquid, which form contact packages with central axial channels in them, characterized in that the annular dividing partitions are rigidly fixed relative to each other and the housing by spacer tubes installed on longitudinal hairpins; which are fixed in the housing, while the continuous contact disks are mounted on the shaft together with the annular contact disks and installed between them, opposite the separating annular partitions by the separating contact disks, forming together the rotor KKD, which is installed in the housing with a minimum clearance relative to the surfaces of the Central holes of the separating ring partitions, while on the lateral surfaces of the KKD, between which flows the gas-vapor mixture (ASG) from the central axial channels to the external ring channels; corrugations are made that form the channel profile of the centrifugal contact packages, while solid, annular and separation contact disks, together with the separation ring partitions and the body, form a zigzag, radial-axial flow of gas and liquid flows. 2. The apparatus according to claim 1, characterized in that the corrugations on the CCD are intermittent, while the distance (L) between the corrugations forming the profiles of the channels of the CBC flow between the CCD does not exceed 3 times the gap (N) between the CCD. 3. The apparatus according to claim 1, characterized in that the corrugation profile on the ACC, along which the CBC flow is directed from the external annular channels to the central axial channels, is made similar to the profile forming the corrugation system on the contact disks of the centrifugal contact packages, and the ACC themselves are installed in the rotor is thus in relation to the CCD of the centrifugal contact packages, so that they form centripetal contact packages. 4. The device according to claim 1, characterized in that more than 70% of the corrugations on the adjacent KKD in each contact package are made equidistant. 5. The apparatus according to claim 1, characterized in that the height of the corrugations is not more than half the size of the gap between the contact disks, and the width (diameter) of the base of the corrugations is not more than 2 times the size of the gap (H) between the ACC. 6. The apparatus according to claim 1, characterized in that the height of the corrugations, their width and their number on the contact disks of the packages, through which the CBC flows from the outer annular channels to the central axial channels, are made smaller than those on the ACC of the centrifugal contact packages. 7. The apparatus according to claim 1, characterized in that on the spacer tubes between the dividing annular partitions in the sections, vanes of the guide apparatus are installed. 8. The apparatus according to claim 1, characterized in that opposite each continuous contact disk in the part of the liquid channel of the housing, additional dividing semi-annular partitions are installed. 9. The apparatus according to claim 1, characterized in that the gaps between the solid contact disks, the ring contact disks and the separation contact disks are made using spacers installed between them on the longitudinal knitting needles. 10. The apparatus according to claim 1, characterized in that the gaps between the solid contact disks, the ring contact disks and the separation contact disks are made due to the stop in the symmetrically made corrugations on the KKD, and a rigid connection between them is ensured by tightening them using longitudinal knitting needles . 11. The apparatus according to claim 1, characterized in that in the lower part of the dividing contact disks and additional dividing semicircular partitions, holes are made for the absorbent duct, and on the spacer tubes between the dividing ring and semicircular partitions in the sections in the liquid channel, vanes of the guide apparatus are installed.

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