SK1662017U1 - The rectification tray with directional flow phase and the rectification column - Google Patents

Abstract

A rectified phase flow rectification tray is described, wherein elbow baffles (1) are inserted into the holes in the tray plate (3), wherein the tray (3) has an inlet with an inlet edge (5) on one side and an outlet on the opposite side with overflow edge (2). The knee baffles (1) are rotated by a truncated outlet portion towards the inlet edge (5), as well as a rectification column consisting of rectified rectilinear flow stages consisting of a shell (4) in which the plates are stacked (3). ) trays with alternating inlets with inlet edges (5) and outlets with overflow edges (2) on the opposite side.

Description

Technical field

The technical solution relates to the construction of rectification tray with rectified phase flow and rectification column. The technical solution belongs to the chemical, petrochemical or food industry.

BACKGROUND OF THE INVENTION

Distillation is one of the most widely used methods of separating a homogeneous liquid mixture into the components contained therein. The distillation process consists of evaporation of a part of the liquid mixture (raw material) and subsequent condensation of the resulting vapors to the product - distillate. The separation of the liquid mixture by distillation requires different volatility of the components of the mixture (i.e. different boiling points at a given pressure, or different saturated vapor pressure at a given temperature). Due to the different volatility of the individual components of the mixture, the more volatile components (i.e., components having a lower boiling point at a given pressure) are preferably concentrated in the vapors formed (and thus in the distillate). In this way, a higher concentration of the volatile components in the distillate is achieved compared to the original raw material. In order to obtain a higher concentration of volatile components in the distillate, the distillate obtained must be subjected to distillation again, and the distillation may be repeated several times in succession. The process of repeated distillation represents so-called. rectification. Rectification - multiple distillation is carried out in tower apparatuses - rectification columns.

During distillation, the substance passes between the steam and the liquid. The amount of transported substance from one phase to another depends both on the size of the interfacial (vapor-liquid) interface and on the time during which both phases are in contact. Thus, a further necessary condition for distillation, apart from the different volatility of the components of the mixture, is to ensure a sufficiently large vapor-liquid interface as well as the time during which the vapor and liquid phases are in contact with each other. For this reason, there are two types of built-in structures built into the columns. filling or storey built-in units. For tray columns, each individual tray (or tray) of the column represents a single distillation. For packed columns, the packing height (depending on the packing type) is a number of height equivalents, with one height equivalent representing one simple distillation. Filling trays are more often used in sorption processes and in the distillation processes tray columns dominate.

Floor columns have undergone a relatively long historical development and their industrial applicability is well documented by practice. The liquid flows through the column as a result of gravity from top to bottom, and the vapor produced by the boiling of the liquid mixture rises through the column from bottom to top. The basic concept of the storey is usually a circular plate treated by various structural elements influencing the transfer of the substance from one phase to another. The tray design must provide liquid retention time on the tray, vapor bubbling through the liquid, and vapor distribution throughout the liquid volume. Depending on the various design elements and modifications, the most frequently used rectification stages are: hat stages, sieve stages, valve stages.

The principle of operation of the hat deck is that the steam comes from the lower floor and is guided through the neck of the hat. Upon reaching the top of the cap, the vapor is rotated and bubbled through the surrounding liquid through openings or cut-outs in the cap wall. The cut-outs in the hat are most often trapezoidal, triangular or rectangular in shape. In some cases the cut-outs are absent.

A common screen tray consists of a perforated plate with a large number of small holes (hole diameters typically range from 3 to 8 mm). The vapors coming from the lower tray pass through the openings and bubble through the liquid that is maintained on the tray due to the pressure of the bubbling vapors.

Valve trays are commonly used in two versions: with movable (floating) or fixed (fixed) valves. There are openings in the deck plate into which the valves are inserted. In the case of a movable valve, this pressure is lifted by the pair coming from the lower level and its stroke is limited by the length of the feet. If the valves are fixed, the principle of operation is similar to the sieves.

Each of these types of storeys shows the pros and cons in various operational and economic-technical parameters. In terms of investment costs are the cheapest sieves and the most expensive hat caps. In terms of process and operating parameters, the valve deck features have the best characteristics, guaranteeing the best separating capability and favorable pressure drop. It is for these reasons (the ratio of low price to favorable operating parameters) that the valve stages have recently been pushed to the forefront. Historically and in practice, however, the best-proven hat trays are best. An extremely important parameter when selecting a suitable type of storey is the extent of use. In this respect, the hat trays clearly dominate. The screen and valve trays are considerably limited by the ratio of the number of vapors coming from the lower tray to the amount of liquid flowing from the higher tray. When the vapor load is high, the effect is that the liquid is excessively entrained by the vapor and does not form a continuous layer of liquid. On the other hand, with too few vapors, they do not have enough energy to keep the liquid on the storey and so-called. excessive tearing, when the liquid flows through the holes and again does not form a continuous layer on the tray. These undesirable effects also occur with excessively low (entrainment) resp. high (tear) amount of flowing liquid. Valve level with fixed valves also has similar limitations to the screen level. In valve stages with movable valves, the effect of excessive tear is eliminated by closing the valve. If the vapors do not have enough energy to lift the valve, the valve closes under the influence of its own weight, respectively. under the weight of the liquid. Of course, in this case, however, there is no rectification and the tray is shut down. The effect of excessive entrainment of liquid under high vapor load is similar to sieve trays or fixed valve trays. The main advantage of the hat trays is that the liquid is maintained on the tray due to the siphon effect and not due to the vapor energy. Thus, even at zero vapor load, the liquid level will always be maintained at the level of the top of the cap, respectively. depending on the design at the level of the level of the overflow edge of the deck. The type of trays is also the least susceptible to excessive entrainment, as the vapors pass through larger openings than sieve or valve trays, resulting in less velocity and kinetic energy. In view of the above facts concerning the extent of use of the individual types of storeys, specific applications are also obvious. Due to their good separating capacity, low price, but low controllability and high susceptibility to changing operating conditions, strainer and valve trays are particularly suitable for large continuous operations. In the given conditions, it is possible to determine in advance quite precisely under what conditions the tray will work, what will be the vapor and liquid load, so that the correct tray variant can be designed. However, in the case of a semi-continuous or batch (batch) operation, where the operating conditions vary practically constantly, the only rational choice is the hat racks, which are, to say the most, self-regulating and operate in a wide range of operating conditions.

These shortcomings provided the opportunity to address this problem by appropriate technical means.

The result of this effort is the construction of the rectified phase with rectified phase flow and rectification column according to the present utility model described below.

The essence of the technical solution

The above-mentioned deficiencies are substantially eliminated by the construction of a rectified stage with a rectified phase flow and a rectification column according to the present invention. Although the hat trays rank among the oldest types, their use is still justified especially in batch plants. The present design of the stage with a guided phase flow is based on the concept of a cap floor. The type of storey maintains the basic principle of the siphon effect of maintaining the liquid, which allows its wide use. At the same time, it improves one of the most important shortcomings of the hat trays, which is the small dividing ability of the tray. Most of the commercially available cap floors are essentially only different by adjusting the apertures in the cap wall, which makes the vapor better distributed into the liquid, while producing smaller bubbles, resulting in increased vapor-liquid interface and improved tray separation capability. The essence of the rectified stage design with a rectified phase flow consists in that it consists of structural elements representing rectifying steam sockets, elbows. The necks are inserted into the pre-prepared holes and welded to the circular tray plate. The steam nozzles themselves are made eg. from a 180 ° elbow blank. The relative flow direction of the steam and the liquid is such that the steam coming from the lower level passes through the openings in the plate and is guided through the rectifier neck. The shape and rotation of the steam nozzle allows the steam to be directed in a horizontal direction. The horizontal flow of liquid on the tray is ensured by the alternate location of the weirs, which is already characteristic of a rectification column made up of the trays described above. The deflection throats are always rotated with the truncated spout towards the leading edge. The specific layout of the steam nozzles, their number on the tray, the mutual distance, size and height of the nozzles depends on the specific application. The detailed and final design of the tray must result from adaanchh operating conditions of the column, such as vapor and liquid loading, column diameter, nature of the distilled mixture, desired separation capacity of the column, feedstock composition and desired distillate composition, etc. However, the present proposal allows for adaptation to a wide range of requirements by changing the number of throats per tray, their size and placement. However, the basic nature of the phase with a rectified phase flow must be maintained. This is represented by the directional throats which are turned into the countercurrent of the liquid. The tray must also contain overflow edges (or other type of overflow) whose alternate placement will provide the required fluid flow.

The advantages of the design of the rectified phase with a rectified phase flow and the rectification column according to the utility model are evident from the effects they exert on the outside. In general, the originality of the present apparatus is that the increased vapor-liquid contact time is used to increase the partitioning capacity of the tray, by channeling the vapor phase flows. The present design of the phase flow baffle maintains the horizontal flow of the liquid, but directs the flow of steam from the vertical to the horizontal direction. The mutual countercurrent arrangement of the phase flows and the increase of the vapor retention time in the liquid results in an intensification of the permeability of the substance and an increase in the separating capacity of the tray. The design simplicity of the present design is more favorable in terms of pressure losses for the vapor flow than the hat trays. The flow is not forced to rotate 180 ° 2 times, instead the flow is gradual in one direction. Moreover, by applying the solution, a better separation capacity of the column is obtained, which is reflected in the column sizes, such a column being smaller under the same operating conditions as the cap column. The simpler design of the tray (and therefore of the column) also results in a reduction in the value of the column pressure drop, resulting in a reduction in operating costs. A relatively high value of investment costs is also a problem of commercially available cap floors. These are caused, inter alia, by the necessity of attaching the cap, which is often solved, for example, by means of a screw connection, or in another way. The simplicity of the present design eliminates the need for additional folding of the caps, since almost the entire construction element can be secured as a blank (180 ° elbow). The simplicity of the proposed solution is not only reflected in the reduction of investment costs. It also reduces the risk of fouling and contamination of individual elements, so it can also be used in applications where the criterion has to be taken into account, which in turn has a favorable effect on operating costs. Of course there is the possibility of choosing different sizes and different number of elements on the storeys, which is necessary for a wide and universal industrial application. The design can also be combined universally with different types of weirs, be it weirs, pipes or other types. It is also possible to choose the material used as various metal materials, plastics or glass. As a result, the solution can be tailored to specific applications according to customer requirements.

BRIEF DESCRIPTION OF THE DRAWINGS

The construction of the rectification tray and the rectified phase flow column according to the invention will be illustrated in more detail in the drawing, where in FIG. 1, the rectification column assembly with rectified phase flow streams is shown in two views. In FIG. 2 shows the mutual flow direction of the vapor and liquid phases on the rectification tray with a rectified phase flow.

EXAMPLES

It will be understood that the individual embodiments of the utility model are presented for illustration and not as limitations of the technical solutions. Those skilled in the art will find or be able to ascertain using no more than routine experimentation many equivalents to specific embodiments of the invention. Such equivalents will also fall within the scope of the following protection claims. It cannot be a problem for the skilled artisan to optimally design the structure and select its elements, so these features have not been solved in detail.

Example 1

In this example of a specific embodiment of the subject matter of the present invention, a rectified phase flow design with rectified phase flow is described, as shown in the three rectification levels shown in FIG. 1. The rectified stage with rectified phase flow is designed so that elbow rectifying steam sockets 1 are inserted into the openings in the circular tray 3 of the tray, the circular tray 3 of the tray has an inlet with inlet edge 5 on the one side and The annular plate 3 of the tray is inserted into the housing 4. The elbow rectifying steam sockets 1 are pivoted by the truncated outlet portion towards the inlet edge 5 as shown in FIG. Second

Example 2

In this example of a particular embodiment of the present invention, a rectified phase flow rectification column is constructed, as shown in FIG. 1. The rectification column is designed as a casing 4 in which plates 3 of the trays are arranged one above the other, having inlets with inlet edges 5 alternately arranged and on the opposite side outlets with overflow edges 2.

Industrial usability

The industrial applicability of rectified phase rectifier trays and rectification column according to the technical solution finds applicability in the chemical, petrochemical or food industry and wherever columns with classical hat trays are used, while maintaining all their advantages.

Claims (2)

PROTECTION REQUIREMENTS A rectified stage with a rectified phase flow, characterized in that bore rectifying steam sockets (1) are inserted into the openings in the tray (3) of the tray #, wherein the tray (3) of the tray has an inlet with a leading edge (5) and on the opposite side, it has an outlet with an overflow edge (2), wherein the elbow deflection steam sockets (1) are rotated by the truncated outlet portion towards the inlet edge (5). A rectification column consisting of rectification trays according to claim 1, characterized in that it consists of a jacket (4) in which the tray plates (3) are stacked one above the other with inlets with inlet edges (5) and on the opposite side of the outlets with overflow edges (2).