WO2016051372A1

WO2016051372A1 - Valve with floating cap and restraint assembly for deployment in valve trays of distillation columns

Info

Publication number: WO2016051372A1
Application number: PCT/IB2015/057519
Authority: WO
Inventors: Ravindra JAYAWANT
Original assignee: Jayawant Ravindra
Priority date: 2014-10-04
Filing date: 2015-10-01
Publication date: 2016-04-07

Abstract

A improved leakage-free valve (000) with floating cap (004) and restraint assembly for deployment in valve trays (001) of distillation columns is capable of operation across a wide range of operational loads of vapor pressure as may be anticipated in said application environment.

Description

Title of the invention:

VALVE WITH FLOATING CAP AND RESTRAINT ASSEMBLY FOR DEPLOYMENT IN VALVE TRAYS OF DISTILLATION COLUMNS

The following specification describes the invention and particularly the manner in which it is to be performed. -: COMPLETE SPECIFICATION :-

Cross references to related applications: This application claims priority from provisional application for patent No. 3150/MUM/2014 dated 04 October 2015 the contents of which are incorporated herein in their entirety by reference.

Copyright Notice: A portion of the disclosure of this patent document contains material subject to copyright protection. The copyright owner has no objection to the reproduction by anyone of the patent document or the patent disclosure as it appears in the official Patent Office records, but otherwise reserves all copyright rights whatsoever. The following notice applies: © 2015, Ravindra Bhaskar Jayawant. All Rights Reserved

[001 ] Field of the invention

[002] The present invention relates generally to the field of mass transfer / flow control elements and more particularly to construction, manner of operation and deployment of an improved leakage-free floating valve for optimum mass transfer between vapour and liquid phases across a wide range of operational loads.

[003] Background of the invention and description of related art

[004] The process of distillation, as traditionally known in the art, is a method for separating the individual components of a mixture by utilizing the differences in their vapor pressure. Distillation begins from a top portion of a column to a bottom portion of the column. Heavier process liquid flows down the column while lighter process vapor ascends up the column. The main components of distillation columns include a vertical shell, where the separation of the process vapor and liquid substances occurs, and column internals, such as fractionation trays or packings. The column internals increase and enhance the separation between the process vapor and liquid. The internal configurations of the column internals such as tray spacing, column diameter, placement of assemblies to enhance flow increase the efficiency and thereby lead to a lesser requirement of energy.

[005] In a typical distillation column arrangement, a number of horizontally oriented surfaces or fractionation trays are mounted in a sealed, vertically oriented vessel known in the industry as a column or tower. Each of the trays may contain numerous openings which enhance the separation of the vapor and liquid. The simple openings allow the lighter process vapor from below the fractionation tray surface to flow through the tray to interact with the heavier process fluid above. However, these simple openings and holes permitted the vapor to shoot or jet upward through the fractionation tray at lower fluid flow rates and flood the tray. This led to inefficient fluid exchange and separation and a reduction in efficiency and capacity of the entire distillation column. In particular, in the chemical industry, a variety of tray designs have been developed to address these encumbrances and increase the efficiency of the mass transfer.

[006] In plate-type distillation columns, liquid and vapour phases are typically made to contact each other to occasion components from one phase being transferred to the other. The amount of diffusion or mass transfer and thus the mass transfer efficiency depend on whether an intimate and uninterrupted phase contact is maintained between the contacted phases. Much research has been conducted with respect to the optimization of designs for distillation and fractionation columns or zones, i.e., a contacting column or zone wherein liquid and vapor phases are counter currently contacted to effect separation of a fluid mixture, as for example, by contacting of the vapor and liquid phases on a series of vertically spaced horizontal trays or plates mounted within the column. Said design research has primarily focused on the design of different tray structures to improve the efficiency of the overall separation process. However, improvements in distillation and fractionation column design are yet needed to increase the efficiency or capacity of the overall separation process and thereby reduce operating and/or fixed costs. Therefore, avoiding inter-stage back-mixing of liquid and vapor has been identified to be a major target for resolution in the quest for better system design.

[007] Bubble caps have traditionally been used as vapour/liquid contactors in distillation columns. Bubble caps consist of a riser which acts as a liquid seal and through which the vapour rises and then proceeds through a forced downward path for being dispersed via slots in said cap into liquid held in an surrounding tray. However, bubble caps have a limited efficiency of maintaining phase contact and are prone to displacement of cap from atop the riser in events of large vapour load. Besides, bubble caps are also expensive to manufacture, thereby limiting their applicability to the field of the present invention. An alternative to bubble caps are sieve trays wherein liquid is maintained on the tray surface by kinetic energy of vapour phase. Cap valves are placed atop orifices through which the vapour rises into the surrounding liquid. However, this system suffers from many drawbacks including displacement of capping valve when vapour pressure drops and/or seepage of liquid through orifices resulting in weeping or dumping effects, either of which are undesirable in intended operations of the distillation columns and cause severe loss of fractionation efficiency. Thus, it would be desirable to have an improved valve design which overcomes shortcomings associated with existing art and effectively address their imperfections.

[008] To provide an alternative to sieve and bubble caps, valve trays were developed to provide a more efficient fluid exchange and separation. The fractionation tray openings were covered with cover plates capable of lifting up under vapor pressure. The cover plate would "float" above each tray opening. The lighter fluid from below the tray lifted the plates in a upwardly sliding motion to create a flow area for the passage of vapor. The lifting plate directed the vapor to flow horizontally through the liquid on the fractionation tray surface. The increased contact between the vapor and liquid provided better interaction and separation between the process fluids. The cover plates are typically called valves. In a cross-sectional survey of state-of-art, various valve designs have been developed to insert the valve into the fractionation tray openings. The cover plate is attached to downward projections or legs and inserted into the tray openings. During installation, a person skilled in the art would insert the valve device into the tray opening. Another person would be required to be at or near the underside of the fractionation tray to bend or turn the legs whereby the valve would not become detached from the opening during vapor lifting and floating. Other prior art devices utilized locking mechanisms such as retainer rings to limit the lifting of the valve above the tray surface.

[009] However, in typical valve trays, hundreds of valves may be installed on the fractionation tray in the hundreds of openings. This is a time consuming process to have two installers insert each valve and then lock it into place by mechanical force or devices. Additionally, the cover plates of prior art valves could become stuck in a closed position to the fractionation tray surface under a vacuum pressure because of non-uniform mechanical bending and the free moving retainer rings. The non-uniform bending could also cause the valve to become stuck in an "open" position where the cover plate is locked above the fractionation tray surface. Weeping or the seepage of fluid to the tray surface below could occur leading to a greatly reduced efficiency and column. Accordingly, there is a need for a fractionation valve which can be easily inserted into the fractionation tray openings. The fractionation valve should be easy and simple to construct while retaining enough strength to operate in the high pressure vapor and liquid environment. The fractionation valve should also move freely within the tray opening such that vapor flowing from below the tray can easily lift the valve at lower vapor pressure while preventing the valve from being closed due to suction.

[010] Prior art, to the limited extent presently surveyed, does not list a single effective solution embracing all considerations mentioned hereinabove, thus preserving an acute necessity-to-invent for the present inventor who, as result of his focused research, has come up with novel solutions for resolving all needs of the art once and for all. Work of the presently named inventor, specifically directed against the technical problems recited hereinabove and currently part of the public domain including earlier filed patent applications, is neither expressly nor impliedly admitted as prior art against the present disclosures.

[01 1 ] A better understanding of the objects, advantages, features, properties and relationships of the present invention will be obtained from the following detailed description which sets forth an illustrative yet-preferred embodiment.

[012] Objectives of the present invention

[013] The present invention is identified in effectively meeting all of the objectives as set out herein under, of which: [014] It is a primary objective of the present invention to provide a leakage-free non-return valve for implementation in vertical multi-stage tray distillation systems that is capable of operation, back-mixing of liquid and vapor in particular, across a wide range of operational vapour-pressure loads.

[015] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided allows no instance of backflow of fluid / condensate or fouling as observed in fixed trays of conventional distillation column assemblies.

[016] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided allows requirement of less number of trays per distillation column.

[017] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided provisions for less energy consumption due to higher distillation efficiency.

[018] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided allows zero losses of process fluids/ vapor and efficiency even during fluctuation of operating parameters such as steam flow / pressure.

[019] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided allows rising vapor to remain in constant contact with the process liquid irrespective of the levels / height of liquid present on the fractionation tray.

[020] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided is simple in design, easy to operate and capable of robust performance with none, or the least minimal, maintenance and replacement requirements.

[021 ] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided is further capable of scalable operations, preferably in plurality to address requirements of industrial applicability.

[022] It is another objective of the present invention in addition to the aforesaid objectives, that the valve so provided, upon implementation, results in a vertical stage tray distillation system with high efficiency and minimal, if not zero, maintenance operations.

[023] These and other objects and advantages of the embodiments herein will become readily apparent from the following detailed description when considered along with the accompanying drawings.

[024] Brief description of drawings

[025] The present invention is explained herein under with reference to the following drawings, in which,

[026] Figure 1 is a schematic perspective top-view of the valve in its application environment according to the present invention.

[027] Figure 2 is a side elevation view of the valve in its application environment according to the present invention.

[028] Figure 3 is a plan view of the valve in its application environment according to the present invention.

[029] Figure 4 is a side elevation view showcasing construction and dimensions of the valve cage fabricated in accordance with the present invention.

[030] Figure 5 is a perspective top-view showcasing construction and dimensions of the valve cage fabricated in accordance with the present invention.

[031 ] Figure 6 is a bottom view showcasing construction and dimensions of the valve cage fabricated in accordance with the present invention.

[032] Figure 7 is a side elevation view showcasing construction and dimensions of the valve cap fabricated in accordance with the present invention. [033] Figure 8 is a perspective top-view showcasing construction and dimensions of the valve cap fabricated in accordance with the present invention.

[034] Figure 9 is a bottom view showcasing construction and dimensions of the valve cap fabricated in accordance with the present invention.

[035] Figure 10 is a photograph showing the application, in plurality, of the valve of the present invention on a plate / tray integrated in distillation column assemblies.

[036] In above drawings, wherever possible, the same references and symbols have been used throughout to refer to the same or similar parts. References made to particular examples and implementations are for illustrative purposes, and are not intended to limit the scope of the invention or the claims. Numbering has been introduced to demarcate reference to specific components, such references being made in different sections of this specification.

[037] Attention of the reader is now requested to the detailed description to follow which narrates a preferred embodiment of the present invention and such other ways in which principles of the invention may be employed without parting from the essence of the invention claimed herein.

[038] Terms and definitions

[039] In this document, following terms shall have their respective meanings, as under:

[040] The term "Tray" shall refer and mean any surface within a tower column used in mass transfer applications wherein typically the dorsal surface of said tray is toward the top of the tower and the underbelly of the tray is toward the bottom of the tower. Several tray openings are positioned throughout the tray surface ordinarily for positioning valves or other devices to regulate the flow of vapors through the liquids. [041 ] Detailed description

[042] The present invention, at the outset, proposes an improved leakage-free valve with floating cap and restraint assembly for deployment in valve trays of distillation columns capable of operation across a wide range of operational loads. Utility of the proposed system is intended to cover distillation, absorption and extraction applications as well. Principally, general purpose of the present invention is to assess disabilities and shortcomings inherent to known systems comprising state of the art and develop new systems incorporating all available advantages of prior art and none of its disadvantages.

[043] A better understanding of the objects, advantages, features, properties and relationships of the present invention will be obtained from the following narration which sets forth an illustrative preferred embodiment and which is indicative of the various ways in which the principles of the invention may be embodied.

[044] Construction and assembly of the valve (000) proposed herein is intended to encompass various embodiments, among which a few are explained below with reference to certain examples that illustrate generically the manner in which principles of the present invention may be employed.

[045] Accordingly, with reference to the accompanying Figures 1 , 2, and 3, it can be appreciated that the proposed improved leakage-free valve (000) comprises a base tray (001) having at least one hollow riser pipe (002) traversing floor of the tray (001). Riser pipe (002) is essentially a tube one end traversing floor of tray (001) and the other end continuing upward to to form an orifice (003). The end of riser pipe (002) traversing floor of tray (001) is flush with underbelly of the tray (001), to result in an arrangement which makes the riser pipe (002) the only channel available for upward flow / escape of vapour accumulated in wake of tray (001).

[046] Avoiding backflow of condensate / liquid through valve (000) while ensuring passage of vapour through said liquid is an important consideration of the present invention. This is achieved, in combination, via height of riser pipe (002), provision of overflow weir (006) on dorsal floor of tray (001), and capping the orifice (003) to hold, retain and otherwise prevent backflow of condensate / liquid through valve (000). Angled overflow weir (006) provisions for receipt of process fluids from tray above, and causing said fluids to overflow into zone of the valve (000) without causing splashing and/ or ripples. Particularly, the height of riser (003) and overflow weir (006) provision for progressive dead retention zones which must be exceeded before any backflow of condensate / liquid occurs through valve (000). Additionally, backflow is prevented by floating cap (004) which selectively closes orifice (003) to thereby allow only unidirectional upward flow / escape of vapour accumulated in wake of tray (001). Further referring generally to the accompanying Figures 5, 6 and 7, it can be seen that cage (005) comprises, in one embodiment, four diametrically opposing arms (009, 010, 01 1 and 012) that circumscribe floating cap (004). Said arms (009, 010, 01 1 and 012) are anchored centrifugally around riser pipe (002), preferably via welding perpendicularly to floor of tray (001), leaving sufficient space in between the riser pipe (002) and arms (009, 010, 01 1 and 012) for movement of floating cap (004). Corresponding free ends of the arms (009, 010, 01 1 and 012) are arranged to meet centrally above centre of the riser pipe (002) at sufficient height to allow the floating cap (004) positioned over riser pipe (002) to be bounded within cage (005) but free to move within a predefined degree of motion allowing said floating cap (004) to alternate, gradually, between CLOSED and OPEN valve positions corresponding with zero and maximum vapour load values respectively as anticipated in the wake of tray (001) during operations of the distillation column. Furthermore, a plurality of gaps (represented by 007) are preserved between body of cage (005) and floor of tray (001), particularly below the arms (009, 010, 01 1 and 012) being joined by a continuous band (013) for stability, for allowing seepage of rising vapour through liquid present in the fractionation trays upon the valve (000) assuming an OPEN position. Construction of cage (005) follows above general sequential steps, or may alternatively be achieved using a die-cast approach. It shall be appreciated that riser pipe (002), floating cap (004) and cage (005) are coaxial, and their centres are collinear with the point where arms (009, 010, 01 1 and 012) meet above floating cap (004). [048] As apparent from the foregoing narration, floating cap (004) is free to move within circumscribing limits of the enclosure or cage (005). Referring generally to Figures 7, 8 and 9, it can been seen that floating cap (004) itself comprises a cylindrical hollow receptacle being closed on all sides, except its base. The riser pipe (002) is arranged to receive the floating cap (004) in a manner allowing underbelly of the opposing closed surface of floating cap (004) to settle flush against mouth of orifice (003) at end of the riser pipe (002), therefore closing orifice (003) and assuming a resting CLOSED position of valve (000). Conversely, at maximum vapour load, the floating cap (004) lifts above orifice (003) due to pressure of the vapour column rising through riser pipe (002) to thereby assume an actuated OPEN position of valve (000), which allows accumulated vapour from under wake of tray (001) to escape in a controlled manner into space above tray (001). Again, when vapour pressure drops, the floating cap (004) settles / sits under its own weight atop riser pipe (002) thereby sealing the orifice (003) and causing valve (000) to return to its resting CLOSED position, which hence allows no further transfer of vapour from under wake of tray (001) to the space above tray (001).

[049] As will be understood, travel of floating cap (004) is dependent on vapour load acting against gravity to lift the floating cap (004), and therefore, valve (000) is capable of attaining intermediate positions between its fully CLOSED and OPEN valve positions depending on vapour pressure value exceeding that necessary for lifting floating cap (004). This arrangement ensures optimum mass transfer between vapour and gravity, and hence phases across a wide range of operational loads across various sections / shelves of the distillation column while never resulting in the floating cap (004) losing its alignment or being displaced from its motion path due to the circumscribing cage (005). Certain alternative embodiments of the present invention suggest implementation of calibrated travel length and weight of floating cap (004) to thereby allow greater control and predictability in operations of valve (000).

[050] Certain inherent advantages of the present invention are seen to be released as result of the peculiar construction of the improved leakage-free valve (000) outlined hereinabove. Foremost, as the floating cap (004) does not ever loose alignment or is displaced from atop the riser pipe (002), thus entirely avoiding the consequentiality of weeping or dumping during operation of the distillation column. Second, as the liquid / condensate is contained within the base tray (001) through which the riser pipe (002) projects upward, the orifice (003) is always maintained at a height above level of said liquid / condensate, thereby eliminating any instance of liquid seepage under gravity into lumen of the distillation column section in the wake of tray (001). Third, the continuous motion of the cap (005) between its CLOSED and OPEN positions eliminates potential of fouling observed in fixed tray internals and thus, results in zero operational downtimes, thereby saving on valuable resources and costs. Also, as evident from the foregoing narration, the improved leakage-free valve (000) proposed herein is simple to manufacture, operate and maintain, thus releasing promise of wide-spread acceptability and industrial applicability in field of the present invention.

[051 ] The present invention has been reduced to practice by the present inventor, and observed to have satisfactory function as intended during trial runs wherein distillation of very low boiling components have been achieved successfully. The aim of distilling the low boiling component has been achieved and tested for different feed capacities. Also there was no leakage through trays observed.

[052] Reference is now made to certain examples which showcase the manner in which principles of the present invention are presently applied. It shall be understood however these examples are merely illustrative and not restrictive of the ways in which the present invention may be implemented.

[053] Example 1 : Construction

[054] In the trials presently undertaken, following determinations and considerations were applied for fabrication of valve (000):

a) Depth of tray (001) admeasuring 8 mm to 12 mm, particularly 10 mm b) Thickness of sheet used for preparing tray (001) ranging between 1 .7 mm to 2.3 mm, particularly 2 mm

c) Height of riser pipe (002) ranging between 25 mm to 35 mm, particularly 30 mm

d) Internal diameter of orifice (003) ranging between 32 mm to 44 mm, particularly 38 mm e) Height of floating cap (004) ranging between 20 mm to 30 mm, particularly 25 mm

f) Internal diameter of floating cap (004) ranging between 35 mm to 45 mm, particularly 40 mm

g) Height of cage (005) ranging between 35 mm to 50 mm, particularly 42 mm

h) Internal diameter of cage (005) ranging between 28 mm to 45 mm, particularly 31 .25 mm

i) Width of arms (009, 010, 01 1 and 012) ranging between 3 mm to 10 mm, particularly 5 mm

j) Height of overflow weir (006) ranging between 8 mm to 12 mm, particularly 10 mm

k) Thickness of sheet used for overflow weir (006) ranging between 1 .7 mm to 2.3 mm, particularly 2 mm

I) Height of gap (007) ranging between 3 mm to 8 mm, particularly 5 mm m) Material of construction of components (002), (004), (006), (009), (010),

(01 1), and (012) being metal chosen among DOW-Cu, its equivalents and their combinations.

[055] Example 2: Deployment in plurality

[056] The improved leakage-free valve (000) proposed herein is intended for deployment either singly or in plurality in a distillation tray environment wherein long maintenance and/or replacement-free life are envisaged. Figure 10 is a photograph showing the application, in plurality, of the valve of the present invention on a plate / tray integrated in distillation column assemblies. (It is submitted that this photograph is an ideal representation for showcasing to-scale implementation of the present invention in real life).

[057] Example 3: Performance and shelf life

[058] The improved leakage-free valve (000) proposed herein has been experimentally verified to result in an increase in efficiency of around 10% as compared to conventional distillation column designs while separating a mixture of methanol + ethanol. Success of the present invention, as outlined in the examples mentioned above, also releases following evolution in the field of distillation, more particularly identified in that:

a) The leakage-free non-return valve (000) proposed herein for implementation in vertical multi-stage tray-based columnar distillation systems is capable of operation while avoiding back-mixing of liquid and vapor in particular, across a wide range of operational vapour- pressure loads as may occur between those responsible for OPEN and CLOSED positions of valve (000).

b) The leakage-free non-return valve (000) proposed herein allows no instance of backflow of fluid / condensate or fouling as observed in fixed trays of conventional distillation column assemblies as a concerted effect of construction and heights of riser pipe (002), position of cap (004), and flow control due to overflow weir (007).

c) The leakage-free non-return valve (000) proposed herein deliberately causes process vapors escaping through the riser pipe (002) to maintain contact, at all times, with the process liquids present on the partition being traversed irrespective of the levels / height of liquid present on the fractionation tray., thereby increasing the efficiency of mass transfer in said distillation column and therefore allowing requirement of less number of trays per distillation column.

d) The leakage-free non-return valve (000) proposed herein provisions for less energy consumption due to higher distillation efficiency as explained in point c) above.

e) The leakage-free non-return valve (000) proposed herein allows zero losses of process fluids/ vapor and efficiency even during fluctuation of operating parameters such as steam flow / pressure as explained in point b) above.

f) The leakage-free non-return valve (000) proposed herein is simple in design as disclosed hereinbefore, is easy to operate in autonomous fashion requiring no power/ manual inputs, and further capable of robust performance with none, or the least minimal, maintenance and replacement requirements as determined in experimental trials undertaken by the present inventor. g) The leakage-free non-return valve (000) proposed herein is capable of scalable operations, preferably in plurality to address scaling requirements of industrial applicability.

h) The leakage-free non-return valve (000) proposed herein so provided, upon implementation, results in a vertical stage tray distillation system with high efficiency and minimal, if not zero, maintenance operations

[060] From the foregoing narration, an able technology for optimum mass transfer between vapour and liquid phases across a wide range of operational loads is thus provided with improved functionality, durability and long service life than any of its closest peers in state-of-art. As will be realized further, the present invention is capable of various other embodiments and that its several components and related details including variations in sizes, geometries of components, such as square, rectangular, triangular or other shape with the same effect, and alternative materials of construction are capable of various alterations, all without departing from the basic concept of the present invention.

[061 ] Accordingly, the foregoing description will be regarded as illustrative in nature and not as restrictive in any form whatsoever. Modifications and variations of the system and apparatus described herein will be obvious to those skilled in the art. Such modifications and variations are intended to come within ambit of the present invention, which is limited only by the appended claims.

Claims

I claim,

1 ] A valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column, comprising:

a) a hollow riser pipe (002) sitting flush against a perforation made in floor of a partition included in said distillation column for allowing process vapors to rise upward, while avoiding backflow of process liquids, through the partition being traversed;

b) an orifice (003) formed by mouth of the riser pipe (002) for receiving a floating cap (004) that allows the flow of process vapors rising upward while avoiding backflow of process liquids present on dorsal surface of the partition being traversed, especially in the event ; and

c) a cage (005) of diameter larger than the floating cap (004) for restraining movement of the floating cap (004) substantially in a manner that ensures optimum contact between the process liquid and process vapor phases at all times to thereby result in an increased efficiency of mass transfer.

2] The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 1 , wherein the partition being traversed is a tray (001) made of sheet metal of thickness chosen between 1 .7 mm to 2.3 mm, preferably 2 mm, and having an average depth chosen between 8 mm to 12 mm, preferably 10 mm, for holding process liquids of the distillation being implemented.

3] The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 2, wherein the tray (001) further optionally comprises a overflow weir (006) of thickness chosen between 1 .7 mm to 2.3 mm, preferably 2 mm, and having an average depth chosen between 8 mm to 12 mm, preferably 10 mm, for receiving process liquids from a partition above the partition being traversed.

4] The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 1 or 3, wherein the riser pipe (002) is arranged to have a height chosen between 25 mm to 35 mm, preferably 30 mm and having an internal diameter chosen between 32 mm to 44 mm, preferably 38 mm which configuration results in avoiding backflow of process liquids due to height of the riser tube being, at all times, well above level of process liquids held in tray (001).

The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 1 , wherein the floating cap (004) is a hollow cylindrical receptacle having its cross-sectional diameter larger than that of the riser pipe (002) and has a height chosen between 20 mm to 30 mm, preferably 25 mm and internal diameter chosen between 35 mm to 45 mm, preferably 40 mm.

The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 1 , wherein the cage (005) is a hollow cylindrical construct comprising arms (009, 010, 01 1 and 012) that are anchored to the floor of the horizontal partition being traversed centrifugally around riser pipe (002) with sufficient space in between accommodate floating cap (004) and arranged to meet centrally above centre of the riser pipe (002) at sufficient height to allow the floating cap (004) positioned over riser pipe (002) to be bounded within cage (005) but free to move within a predefined degree of motion.

The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 6, wherein the predefined degree of motion is bounded by limits of travel of floating cap (004) corresponding with a CLOSED position at zero and OPEN position at maximum vapour load of about 0.5 kgcm^"2 occurring in wake of the partition being traversed.

The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 6, further comprising a band (013) serving as the connection between arms (009, 010, 01 1 and 012) is positioned at a height between 3 mm to 10 mm, particularly 5 mm above floor of the partition being traversed to provide a gap (007) deliberating process vapors escaping through the riser pipe (002) to maintain contact, at all times, with the process liquids present on the partition being traversed, thereby increasing the efficiency of mass transfer in said distillation column. ] The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 6, wherein gaps between arms (009, 010, 01 1 and 012) allow the floating cap (004) to be held shut under positive pressure in the event the level of liquid above the partition being traversed exceeds the height of riser tube (002) thereby avoiding any instance of flooding of the distillation column. 0] The valve (000) for increasing the efficiency of mass transfer and avoiding backflow of process liquids in a horizontally-partitioned vertical distillation column as claimed in claim 1 , wherein material for construction of components (002), (004), (006), (009), (010), (01 1), and (012) is chosen among DOW-Cu, its equivalents and their combinations.