Devolving apparatus equipped with a static mixer and a distributor

Abstract

The present invention relates to a defloration apparatus for deflorating a composition containing volatile components, such as for deflorating a solid or liquid polymer composition containing unreacted monomers, a solvent, and / or by-products, wherein the defloration apparatus comprises a container having an inlet for the composition to be deflored, at least two overlapping and spaced-apart partitions, at least one outlet for the deflorated composition, and at least one outlet for the gas, and each of the at least two partitions comprises at least one static mixer.

Description

【Technical Field】 【0001】 The present invention relates to a devolatilization apparatus for devolatilizing a composition containing volatile components, such as for devolatilizing a solid or liquid polymer composition containing unreacted monomers and solvents, a plant for polymer preparation comprising at least one such devolatilization apparatus, and a devolatilization method using such a devolatilization apparatus. 【Background Art】 【0002】 Devolatilization, i.e., degassing, respectively refers to removing gas and other volatile substances such as solvents or moisture from solids and liquids under control. Devolatilization is usually used to remove volatile components, which are mostly components having a relatively low molecular weight such as residual monomers, solvents, reaction by-products, and water from polymers. This devolatilization is necessary to achieve the required purity of each polymer before use by removing harmful and / or toxic components, components that adversely affect further processing of the polymer such as moldability of the article, components that deteriorate the properties of the polymer, components that cause an unpleasant odor of the polymer, and / or components that are otherwise undesirable. Furthermore, removing monomers and solvents from the polymer composition makes it possible to recover and potentially recycle the monomers and solvents during the process so as to increase the yield of the process and reduce the amount of waste. 【0003】 To achieve defoliation, the components to be evaporated must each have a higher partial pressure or thermodynamic activity than the polymer. Furthermore, the components to be evaporated must be able to diffuse through the polymer composition to the phase boundary. Specifically, in the case of viscous polymers or polymer melts, where the polymer and polymer melt typically have similar viscosity, a slow diffusion rate can be a rate limiting factor. Therefore, to accelerate defoliation, the composition to be defoliated is usually defoliated at high temperatures and / or at pressures below atmospheric pressure. This is because both measurements increase the thermodynamic activity of the volatile components, and further, as the temperature increases, the viscosity of the polymer decreases, thereby improving the diffusion of volatile components within the polymer. 【0004】 Several types of devolatilization devices are known, including static and dynamic devolatilization devices. Dynamic devolatilization devices have moving parts such as blades to maintain a high interfacial concentration gradient and a high diffusion rate of volatile components within the polymer, while static devolatilization devices do not have moving parts but have internal structures such as one or more trays, specifically perforated trays, to produce a high specific surface area of ​​the composition to be devolatilized and to distribute the composition to be devolatilized across the entire cross-section of the devolatilization device. However, dynamic devolatilization devices are associated with serious drawbacks due to their moving parts, such as high cost, high energy consumption during operation, the need for periodic maintenance, and a relatively high leakage rate. 【0005】 Therefore, compared to dynamic devolatilization apparatuses, static devolatilization apparatuses have advantages such as lower energy consumption, lower installation costs, less maintenance required, and a relatively low leakage rate, due to the absence of moving parts. Common types of static devolatilization apparatuses are flash devolatilization apparatuses and falling strand devolatilization apparatuses. Flash devolatilization apparatuses typically comprise a preheater, such as a heat exchanger, and a flash chamber. During operation, the polymer composition to be devolatilized is first pumped to the heat exchanger, where it is heated and optionally pressurized to reduce its viscosity. The polymer composition is then pumped from the heat exchanger to the top of the flash chamber, where the pressure is released and evaporation of volatile components occurs. The polymer composition then falls downward through the flash chamber, during which time multiple bubbles of volatile components are nucleated within the polymer composition. This results in a larger surface area for mass transfer, and therefore leads to rapid devolatilization. The defolable gas phase is collected and condensed in a condenser, while the residual polymer composition is collected at the bottom of the flash chamber and removed by pumping. A drop strand defollation system operates similarly to a flash defollation system, but includes one or more perforated trays to generate a high specific surface area of ​​the composition to be defolated, to distribute the composition to be defolated across the entire cross-section of the defolation system, to form drop strands of the composition to be defolated, to promote the development of bubbles of volatile components, and to accelerate the diffusion process. 【0006】 To provide flexibility with respect to the compositions to be defolable, such as polymers, the defolable apparatus is preferably suitable for use in defolating a wide range of compositions, specifically compositions with relatively high viscosity and compositions with relatively low viscosity. Such flexibility is required in industrial polymerization plants because various product grades are produced in various subsequent production charges, including polymers with various molecular weights and / or polymers with various polymer structures such as linear, branched, and cross-linked structures, and consequently polymers with various viscosities. For example, one example is the production of polycaprolactone, an advanced bioplastic derived from fossils but biodegradable, suitable as an additive in medical applications and polyurethane production. Various polymer grades, i.e., polycaprolactone with various molecular weights and / or polycaprolactone with various polymer structures, are produced in various subsequent batches in a single polymerization plant. Therefore, the devolatilizer included in this polymerization plant should be able to process any of the produced batches independently of the viscosity of the polymer melt and should be able to provide an optimal residence time for devolatilizing the polymer melt to the desired degree. However, to prevent the internal structure of the devolatilizer from becoming blocked during the devolatilization of high-viscosity compositions, for example, by the blockage of openings in the internal structure by the high-viscosity composition being devolatilized, devolatilizers are usually designed only for high-viscosity compositions. As a result, typical devolatilizers are not optimized at all for devolatilizing low-viscosity compositions and perform insufficient devolatilization of low-viscosity compositions. 【0007】 Alternatively, the devolatilization apparatus may be designed to devolatilize only low-viscosity compositions. However, in this case, the devolatilization apparatus cannot be used to devolatilize high-viscosity compositions. [Prior art documents] [Patent Documents] 【0008】 [Patent Document 1] International Publication No. 2010 / 066457A1 [Patent Document 2] European Patent Application Publication No. 1206962A1 [Patent Document 3] European Patent No. 2158027B1 [Patent Document 4] European Patent No. 0655275B1 [Patent Document 5] U.S. Patent No. 3,743,250(A) [Patent Document 6] European Patent No. 2548634B1 [Patent Document 7] European Patent No. 0815929B1 [Patent Document 8] European Patent No. 1510247B1 [Patent Document 9] U.S. Patent No. 4,093,188(A) [Patent Document 10] U.S. Patent No. 4,296,779(A) [Overview of the Initiative] [Problems that the invention aims to solve] 【0009】 In this regard, the fundamental objective of the present invention is to provide a devolatilization apparatus for devolatilizing compositions containing volatile components, such as solid or liquid polymer compositions containing unreacted monomers, solvents, and / or by-products. The devolatilization apparatus enables efficient and low operating cost devolatilization in a compact design not only of high-viscosity compositions having a kinematic viscosity of at least 1,000 Pa·s, but also of low-viscosity compositions having a kinematic viscosity of less than 1,000 Pa·s, particularly less than 500 Pa·s. Therefore, the devolatilization apparatus is scalable and may be used to devolatilize polymer melts, such as polycaprolactone polymer melts, for various grades of polymers, i.e., it is variable with respect to the structure and molecular weight of the polymer charge produced. [Means for solving the problem] 【0010】 The present invention provides a defoliation apparatus for defoliating a composition containing volatile components, such as for defoliating a solid or liquid polymer composition containing unreacted monomers, a solvent, and / or by-products, wherein the defoliation apparatus comprises a container having an inlet for the composition to be defoliated, at least two overlapping and spaced-apart partitions, at least one outlet for the defoliated composition, and at least one outlet for the gas, and each of the at least two partitions is equipped with at least one static mixer. 【0011】 The devolatilization apparatus according to the present invention comprises at least two distinct supply points and distributors, by dividing the container of the devolatilization apparatus into several, i.e., at least two, sections, each of which is equipped with a distributor, and each of the distributors being equipped with at least one static mixer, i.e., by dividing the container of the devolatilization apparatus into at least two devolatilization sections. The at least two distinct supply points and distributors may be optimized for various charges of polymer melts containing polymers of various polymer grades, i.e., polymers having different molecular weights and / or different structures, and consequently different viscosities, so as to enable devolatilization of high-viscosity compositions and low-viscosity compositions. Thus, depending on the viscosity of the polymer, determined by the molecular weight, structure, and monomer content of the polymer melt leaving the polymerization reactor, the devolatilization apparatus according to the present invention enables the supply of the polymer melt through one of the at least two distinct distributors, i.e., at one of the at least two distinct supply points, to a suitable devolatilization section that is appropriate and optimized for processing the polymer melt at a given viscosity and optimal residence time, thereby realizing a target polymer with the desired quality. Specifically, the static mixer in each distributor allows for adjustment of the pressure drop in each distributor so that only polymer melts with a suitable viscosity enter each distributor. Thus, the static mixer in each distributor not only mixes the polymer melts before devolatilization, but also, in practice, controls which of at least the devolatilization zones each polymer melt to be devolatilized is supplied to, depending on the viscosity of the polymer melt. Overall, the devolatilization apparatus according to the present invention enables efficient and low-operating-cost devolatilization in a compact design not only of high-viscosity compositions having a kinematic viscosity of at least 1,000 Pa·s, but also of low-viscosity compositions having a kinematic viscosity of less than 1,000 Pa·s, particularly polycaprolactone polymer melts of different polymer grades, such as less than 100 Pa·s. 【0012】 The fact that the distributor comprises at least one static mixer means that at least one static mixer is directly connected to the distributor, for example, the upstream end of the distributor, so that the composition contained in the distributor or processed in the mixer flows directly into the distributor. Preferably, at least one of the at least two distributors, more preferably each, has an inlet for the composition to be devolatilized at its upstream end and an outlet for distributing the composition to be devolatilized into a container at its downstream end, with at least one static mixer positioned downstream of the inlet and upstream of the outlet. However, as stated above, it is also possible that at least one static mixer is directly connected to the distributor, for example, the inlet of the distributor. 【0013】 Favorable results are particularly obtained when at least one static mixer is located directly upstream of the upstream end, or downstream of or at least near the downstream end of the upstream end of each distributor, because the static mixer can allow or prevent each composition to be defolable from entering each distributor before the composition enters the distributor. In this regard, it is preferable that in at least one of the at least two distributors, more preferably each, the static mixer is located directly upstream of the inlet, directly downstream of the inlet, or downstream of the inlet such that the distance between the inlet and the uppermost end of the static mixer is less than 20%, preferably less than 10%, more preferably less than 5%, and most preferably less than 1% of the length of the distributor. In this context, the length of the distributor means the distance between the uppermost and lowermost ends of the distributor. 【0014】 Therefore, in each of the at least two distributors described above, it is preferable that the static mixer is positioned directly upstream of the inlet, directly downstream of the inlet, or downstream of the inlet of each distributor such that the distance between the inlet and the uppermost end of the static mixer is 10 cm or less, preferably 5 cm or less, and more preferably 0.5 cm or less. 【0015】 According to the present invention, each of at least two distributors comprises at least one static mixer. According to the present invention, a static mixer is defined as a stationary device comprising at least two deflection means, not openings, orifices, for mixing a single-phase or two-phase fluid flow, preferably continuously. Preferably, the static mixer comprises a housing having one or more inlets, one or more outlets for the mixed fluid, and an internal flow path in which at least two deflection means are arranged. Furthermore, the two deflection means are preferably selected from the group consisting of plates, bars, crossbars, baffles, helically formed deflection means, grids, and any combination of two or more of the aforementioned deflection means. In addition, the static mixer preferably comprises at least three, more preferably at least five, and even more preferably at least ten deflection means, where each bar, plate, crossbar, helically formed deflection means, and grid counts as one deflection means. Specifically, the static mixer is designed to achieve a mixing effect for layered single-phase fluid flows and even more so for two-phase fluid flows. Static mixers draw energy from the fluid itself to mix the fluid flow and require no additional power source. Preferred examples of static mixers include X-type static mixers, vortex / spiral-type static mixers, quattro-type static mixers, baffle plate-type static mixers, turbulator-strip-type static mixers, and any combination of two or more of the above mixer types. An X-type static mixer comprises deflection means in the form of bars, crossbars, plates, etc., which have an X-shaped configuration in plan view, side view, and / or cross view. Such X-type static mixers are described, for example, in International Publication No. 2010 / 066457A1, European Patent Application Publication No. 1206962A1, European Patent No. 2158027B1, and European Patent No. 0655275B1, and are commercially available from Sulzer Chemtech Ltd, Winterthur, Switzerland under the trade names SMX, SMXL, and SMX plus, and from Fluitec, Neftenbach, Switzerland under the trade name CSE-X.A vortex / spiral static mixer has a spirally formed deflection means and is described, for example, in U.S. Patent No. 3,743,250(A), while a quattro static mixer has a deflection means that forms a chamber-like mixing area and is described, for example, in European Patent No. 2548634B1 and European Patent No. 0815929B1. Baffle plate type static mixers typically feature longitudinal deflection means and are described, for example, in European Patent No. 1510247B1 and U.S. Patent No. 4,093,188(A), while turbulator strip type static mixers feature multiple elongated strips within a tube and are described, for example, in U.S. Patent No. 4,296,779(A), each elongated strip being formed by a series of alternating deflection panels continuously joined together, for example, by substantially triangular bridging portions, with the strips being held together and substantially fixed to the axis of the tube by every other bridging portion, and the other bridging portions being located adjacent to the inner wall of the tube. Other suitable static mixers are available from Sulzer Chemtech AG under the trade names CompaX, SMI, KVM, SMV, and GVM, and from Stamixco AG, Wollerau, Switzerland under the trade name GVM. From the above standpoint, it is preferable that at least one, more preferably all, of the at least one static mixers in the at least two distributors be selected from the group consisting of X-type static mixers, vortex / spiral-type static mixers, quattro-type static mixers, baffle plate-type static mixers, turbulator / strip-type static mixers, and any combination of two or more of the above mixer types. 【0016】 In order to easily distribute the composition to be devolatilized to a suitable dispenser and through the suitable dispenser, in a further development of the idea of the present invention, it is suggested that the devolatilization device further comprises a distribution line, the distribution line having an inlet for the composition to be devolatilized at one of its ends and being further connected to each of the inlets of the at least two dispensers. Thereby, the composition to be devolatilized can flow through the inlet into the distribution line, which may be a pipe, and then along the distribution line to enter the appropriate dispenser for the composition actually supplied through the distribution line. 【0017】 For example, the distribution line may comprise at least two valves, and each of the inlets of the at least two dispensers is connected to one of the at least two valves. 【0018】 According to the present invention, the devolatilization device comprises a container having at least two dispensers that are overlapping and spaced apart. According to a particularly preferred embodiment of the present invention, each of the at least two dispensers, which is arranged above another of the at least two dispensers, has a higher pressure loss than the other dispenser. In other words, the devolatilization device is embodied such that while the low-viscosity composition to be devolatilized is allowed to enter the uppermost dispenser or at least one of the uppermost dispensers, the composition to be devolatilized having a higher viscosity can only enter one of the lower dispensers or even only the lowermost dispenser. 【0019】 Each pressure loss distribution, that is, each of the at least two dispensers, which is arranged above another of the at least two dispensers, having a higher pressure loss than the other dispenser can be easily achieved by appropriately selecting a static mixer for a single dispenser, that is, as a result, preferably, at least one static mixer of the dispenser arranged above another dispenser produces a higher pressure loss than at least one static mixer of the other dispenser located below that dispenser during operation. 【0020】 Each pressure loss distribution, i.e., each of the at least two distributors positioned above one of the at least two distributors, can also be realized by having different cross-sectional areas of the distributors. Thus, in addition to the above embodiment using static mixers that achieve different pressure losses during operation, or in place of the above embodiment using static mixers that achieve different pressure losses during operation, each of the at least two distributors positioned above the other distributor may have a smaller cross-sectional area (such as a smaller diameter in the case of a distributor with a circular cross-section) than at least one other distributor located below it. Good results can be achieved, for example, if each of the at least two distributors is a pipe or has an upstream portion that is a pipe, and the pipe of the distributor positioned above the other distributor has a smaller cross-sectional area diameter than the pipe of the other distributor. The pipe or portion embodied as a pipe may have any kind of cross-sectional shape, such as circular, square, rectangular, elliptical, oblong, or polygonal cross-sectional shapes. Preferably, the pipe or portion embodied as a pipe has a circular cross-section. Most preferably, each of the at least two distributors is a pipe having an inclined downstream end. 【0021】 According to yet another embodiment of the present invention, each pressure loss distribution, that is, each of the at least two distributors disposed above another distributor among the at least two distributors, can also be realized by making the distributor lengths of a single distributor different. As a result, in addition to the above embodiments using a static mixer that realizes different pressure losses during operation and / or a distributor having different cross-sectional areas, or instead of the above embodiments using a static mixer that realizes different pressure losses during operation and / or a distributor having different cross-sectional areas, each of the at least two distributors disposed above another distributor may be longer than at least one other distributor located below that distributor. Good results are achieved, for example, when each of the at least two distributors is a pipe or includes an upstream portion that is a pipe, and the pipe of the distributor disposed above another distributor is longer than the pipe of the other distributor. Also in this case, the pipe or the portion embodied as a pipe may have any type of cross-sectional shape, such as a circular, square, rectangular, elliptical, oval, or polygonal cross-sectional shape. Preferably, the pipe or the portion embodied as a pipe has a circular cross-section. Most preferably, each of the at least two distributors is a pipe having an inclined downstream end. 【0022】 In a further development of the idea of the present invention, it is proposed that each of the at least two distributors is disposed at least substantially horizontally in the container and extends from one end of the container over 20% to 80% of the width of the container. Being at least substantially horizontal means, in the context of the present invention, that the angle between the longitudinal direction of the distributor and the horizontal plane is less than 20°, preferably less than 10°, more preferably less than 5°, even more preferably less than 1°, and most preferably 0°. Good results are particularly achieved when each of the at least two distributors is disposed at least substantially horizontally in the container and extends from one end of the container over 20% to 60%, more preferably 25% to 50% of the width of the container. Most preferably, each of the at least two distributors is disposed horizontally in the container. 【0023】 Regarding the material from which the above-mentioned at least two partitions are fabricated, there are no specific limitations as long as the material is resistant to the composition to be deflated and is mechanically stable. Furthermore, it is preferable that the partition material has relatively good thermal conductivity. Particularly good results are obtained when each partition is made from stainless steel, carbon steel, Hastelloy, etc. 【0024】 According to another preferred embodiment of the present invention, the at least two distributors may be heatable. For example, each of the at least two distributors may have a bottom made of two plates stacked with a gap between them, and the cavity between the two plates may be filled with a heating medium to heat the upper bottom plate to an optimal temperature. 【0025】 The container of the daphne apparatus according to the present invention is divided into at least two daphne regions when viewed vertically. Any region is designated as a daphne region, formed between the top of one distributor and the top of the next lower distributor. Thus, each daphne region comprises one distributor. 【0026】 Further development of the concept of the present invention suggests that each davoltation area is provided with at least one perforation tray, that is, in other words, that each davoltation area is provided with one distributor and at least one perforation tray. 【0027】 Furthermore, it is preferable that the uppermost devolatilization section has more perforated trays than one or more of the lower devolatilization sections. This ensures that the uppermost devolatilization section has a higher capacity than the devolatilization sections located below it. This contributes to the good scalability of the devolatilization device. 【0028】 Particularly favorable results are obtained when each devolatilization area located above another devolatilization area has more perforated trays than the next devolatilization area below it. 【0029】 In general, the daphne apparatus container according to the present invention comprises preferably 2 to 20, more preferably 3 to 10, and even more preferably 4 to 6 distributors arranged in a stacked and spaced-apart manner. 【0030】 In a particularly preferred embodiment of the present invention, the number of trays in each devolatilization area decreases from the uppermost devolatilization area to the lowermost devolatilization area. Particularly good results are obtained when the container of the devolatilization apparatus according to the present invention comprises three distributors and three associated devolatilization areas: a first devolatilization area between the top of the first uppermost distributor and the top of the second central distributor, a second devolatilization area between the top of the second central distributor and the top of the third lowermost distributor, and a third devolatilization area between the top of the third lowermost distributor and the bottom of the container. In this embodiment, it is preferable that three perforated trays are spaced apart and overlapping in the first devolatilization area, while two perforated trays are spaced apart and overlapping in the second devolatilization area, and one perforated tray is arranged in the third devolatilization area. 【0031】 The present invention is not specifically limited with respect to the shape and size of the perforating trays. Good results can be achieved, for example, if at least one, more preferably all, of the perforating trays have a polygonal, rectangular, square, circular, elliptical, or trapezoidal shape when viewed from the top. However, it is preferable that at least one, more preferably all, of the perforating trays have a circular shape when viewed from the top. 【0032】 Furthermore, there are no specific restrictions on the material of the perforation tray, as long as the material is resistant to the composition to be deflated and is mechanically stable. In addition, it is preferable that the material of the perforation tray has relatively good thermal conductivity. Particularly good results are obtained when at least one, more preferably all, of the perforation trays are made of stainless steel, carbon steel, etc. 【0033】 The preferred thickness of the perforation trays depends on the mechanical stability of the material from which one or more perforation trays are made. Good results can be obtained, for example, when at least one, more preferably all, of the perforation trays have a thickness of 2 to 20 mm, more preferably 5 to 10 mm. 【0034】 Furthermore, it is preferable that at least one, more preferably all, of the perforating trays be positioned at least substantially horizontally in the container and extend at least substantially across the entire cross-section of the container. Extending at least substantially across the entire cross-section of the container means, in this context, that at least one, more preferably all, of the perforating trays extend at least 80%, preferably at least 90%, more preferably at least 95%, even more preferably at least 99%, and most preferably across the entire cross-section of the container. Again, being substantially horizontal means, in this context, that the angle between the longitudinal direction of the perforating tray and the horizontal plane is less than 20°, preferably less than 10°, more preferably less than 5°, and most preferably less than 1°. Most preferably, each of at least two trays is positioned horizontally in the container. 【0035】 In a further development of the spirit of the present invention, it is proposed that at least one weir is positioned on the outer edge of each perforation tray, and that at least one weir extends at least substantially vertically upward from the surface of each perforation tray. Being at least substantially vertical means that the angle between the at least one weir and the vertical is at most 10°, preferably at most 5°, more preferably at most 1°, and most preferably 0°. Preferably, the at least one weir surrounds the perforation tray in a fluid-seal manner so that the liquid contained on the surface of the perforation tray cannot flow outside the perforation bottom element except through an opening provided at the bottom of the perforation tray. 【0036】 When the height of at least one of the weirs is 1 to 1,000 cm, more preferably 10 to 1,000 cm, and even more preferably 100 to 500 cm, particularly good results can be obtained. 【0037】 According to the present invention, each perforated tray has a plurality of openings. The present invention is not specifically limited with respect to the cross-sectional shape of the openings of the perforated tray. For example, some or preferably all of each opening of the perforated tray may have a polygonal, rectangular, square, circular, elliptical, or trapezoidal cross-sectional shape. More preferably, at least some and most preferably all of each opening of the perforated tray have a circular cross-sectional shape. 【0038】 All of the openings in the perforation tray may have the same shape and cross-sectional area, or they may differ in shape and / or cross-sectional area. Even if all of the openings in each tray have the same cross-sectional area, the openings in one tray may have a different cross-sectional area from the openings in another tray. 【0039】 Favorable results are particularly obtained when each of the openings in a tray has at least substantially the same cross-sectional area. This means that the openings in any given tray have at least substantially the same cross-sectional area, and the cross-sectional area of ​​one tray's opening may differ from that of another tray's opening. At least substantially the same cross-sectional area means that each of the tray's openings has a cross-sectional area of ​​70-130%, preferably 80-120%, more preferably 90-110%, even more preferably 95-105%, and most preferably equal to the average cross-sectional area of ​​the openings in each tray. The average cross-sectional area of ​​the tray's openings is the sum of the cross-sectional areas of all the openings in each tray divided by the total number of openings in each tray. 【0040】 According to another preferred embodiment of the present invention, at least one perforated tray, more preferably each perforated tray, has a plurality of openings, wherein the average cross-sectional area of ​​the openings of a tray located in a devolatile area positioned above another devolatile area is smaller than the average cross-sectional area of ​​the openings of a tray located in a devolatile area below. 【0041】 Further development of the concept of this invention suggests that the davoltaic device may not include any back pressure valve. 【0042】 In a further embodiment, the present invention relates to a polymer preparation plant comprising at least one polymerization reactor, the outlet of at least one polymerization reactor being connected to at least one of the above-mentioned defoliation devices. 【0043】 Preferably, at least one polymerization reactor is a plug-flow reactor. 【0044】 The plant may comprise two or more reactors and one, two or more of the above-mentioned davoltaic devices. 【0045】 In a further embodiment, the present invention relates to a method for defoliating a composition containing volatile components, comprising the steps of: supplying the composition to be defoliated to an inlet for the composition to be defoliated in a defoliation apparatus; drawing out a gas from a gas outlet; and drawing out the defoliated composition from an outlet for the defoliated composition. 【0046】 Particularly favorable results are obtained when the composition to be defoliated is selected from the group consisting of polycaprolactone, polyolefin elastomer, polylactic acid, polyglycolic acid, polyolefin, and mixtures or copolymers of two or more of the above polymers. 【0047】 Subsequently, this patent application will be described by reference to advantageous embodiments and the accompanying drawings. [Brief explanation of the drawing] 【0048】 [Figure 1a] This is a schematic longitudinal cross-sectional view of a daphne apparatus according to one embodiment of the present invention. [Figure 1b] This is a schematic longitudinal cross-sectional view of a daphne apparatus according to one embodiment of the present invention. [Figure 1c] This is a schematic longitudinal cross-sectional view of a daphne apparatus according to one embodiment of the present invention. [Figure 2a] This figure shows four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 2b] This figure shows four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 2c] This figure shows four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 2d] This figure shows four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 2e] This figure shows four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Modes for carrying out the invention] 【0049】 The defoliation apparatus 10 shown in Figure 1, for defoliating compositions containing volatile components, such as solid or liquid polymer compositions containing unreacted monomers, solvents, and / or by-products, comprises a distribution line 12 having an inlet 14 at one end for the composition to be defoliated, and a container 16. The container 16 comprises three partitioned and overlapping distributors 18, 18', and 18''. Thus, the container 16 comprises three deflorescence zones 20, 20', and 20'', namely, a first deflorescence zone 20 between the top of the uppermost distributor 18 and the top of the second distributor 18', a second deflorescence zone 20' between the top of the second distributor 18' and the top of the lowermost distributor 18'', and a third deflorescence zone 20'' between the top of the lowermost distributor 18'' and the bottom of the container 16. In addition, the container 16 comprises an outlet 22 for the deflorescence composition and an outlet 24 for the gas. Each of the three distributors 18, 18', and 18'' is a pipe having an upstream end and an inclined downstream end, with a static mixer 26 located at the upstream end of each. Furthermore, the distribution line 12 is equipped with three valves 28, and each of the inlets of the three distributors 18, 18', and 18” is connected to another of the three valves 28. Below each of the distributors 18, 18', and 18” is positioned at least one perforated tray 30; that is, below the uppermost distributor 18, there are three perforated trays 30, below the second distributor 18', there are two perforated trays 30, and below the lowermost distributor 18” there is one perforated tray 30. As specifically shown in Figure 1b, each perforated tray 30 has a circular cross-section and is equipped with a plurality of circular openings 32. The circumference of each perforated tray 30 is equipped with a weir 34 that extends vertically. 【0050】 During the operation of the defolatorializer 10, the composition to be defolatorialized is supplied to the distribution line 12 via an inlet 14 for the composition to be defolatorialized, and from there to one of the distributors 18, 18', and 18'' via one of the valves 28. More specifically, each of the distributors 18, 18', and 18'' has a specific pressure loss due to the properties of the static mixer 26 applied, the length of the distributors 18, 18', and 18'', and the cross-sectional area of ​​the distributors 18, 18', and 18'', namely the highest pressure loss at the uppermost distributor 18 and the lowest pressure loss at the lowermost distributor 18''. For this reason, low-viscosity polymer melts enter the uppermost distributor 18, while medium-viscosity melts enter the middle distributor 18', and high-viscosity polymer melts enter the lowermost distributor 18''. From each of the distributors 18, 18', and 18'', the polymer molten material flows onto the next lower perforated tray 30, where it is distributed across the entire cross-section of the perforated tray and flows through the opening 32 onto the next lower perforated tray 30 or onto the bottom of the container 16. The defolatant polymer is withdrawn from the container 16 via the outlet 22, while the separated gas is withdrawn from the container 16 via the outlet 24. 【0051】 Figure 2 shows five different types of static mixers usable in the devolatilization apparatus and method according to the present invention, namely, Figure 2a shows an X-shaped static mixer 26 equipped with a crossbar-shaped deflection means 36 having an X-shape in both plan and side views. Figure 2b shows a baffle plate-type static mixer 26 equipped with a longitudinal deflection means 36, while Figures 2c and 2d show static mixers 26 equipped with a curved deflection means 36. Figure 2e shows a combined static mixer 26 and heat transfer element equipped with a tubular heat transfer element 38 for transporting a heat transfer medium within a tube, such as the one marketed as SMR by Sulzer Chemtech Ltd, where the tubular heat transfer element 38 also functions as a deflection means for the liquid being transported outside the tubular heat transfer element. [Explanation of symbols] 【0052】 10 Devolatilization equipment 12 distribution lines 14 Inlet for composition to be defoliated 16 Container 18 Distributor 18' distributor 18” distributor 20 Devolatilization area 20' Devolatilization area 20” Devolatilization area 22. Outlet for defoliated composition 24 Gas outlet 26 Static mixer 28 valves 30 perforation trays 32 Tray opening 34 Weir 36 Static mixer deflection means 38 Heat transfer elements of a static mixer

Claims

[Claim 1] A defloration apparatus (10) for deflorating a composition containing volatile components, such as for deflorating a solid or liquid polymer composition containing unreacted monomers, solvents, and / or by-products, wherein the defloration apparatus (10) comprises a container (16) having an inlet for the composition to be deflorated, at least two partitions (18, 18', 18") arranged in overlapping and spaced apart, at least one outlet (22) for the deflorated composition, and at least one outlet (24) for the gas, and each of the at least two partitions (18, 18', 18") comprises at least one static mixer (26). [Claim 2] The daphne generator (10) according to claim 1, wherein each of the at least two distributors (18, 18', 18") has an inlet at its upstream end and an outlet at its downstream end, and the at least one static mixer (26) is located directly upstream of the inlet, or downstream of the inlet and upstream of the outlet. [Claim 3] The daphne generator (10) according to claim 1 or 2, wherein in each of the at least two distributors (18, 18', 18"), a static mixer (26) is positioned directly upstream of the inlet, directly downstream of the inlet, or downstream of the inlet such that the distance between the inlet and the uppermost end of the static mixer (26) is less than 20%, preferably less than 10%, more preferably less than 5%, and most preferably less than 1% of the length of the distributors (18, 18', 18"). [Claim 4] The daphne generator (10) according to any one of claims 1 to 3, wherein in each of the at least two distributors (18, 18', 18"), a static mixer (26) is positioned directly upstream of the inlet, directly downstream of the inlet, or downstream of the inlet such that the distance between the inlet and the uppermost end of the static mixer (26) is 10 cm or less, preferably 5 cm or less, more preferably 0.5 cm or less. [Claim 5] The davoltation apparatus (10) according to any one of claims 1 to 4, wherein at least one, preferably all, of the at least one static mixer (26) is selected from the group consisting of an X-type static mixer, a vortex / spiral-type static mixer, a quattro-type static mixer, a baffle plate-type static mixer, a turbulator / strip-type static mixer, and any combination of two or more of the mixer types. [Claim 6] The daphne generator (10) according to any one of claims 1 to 5, wherein the daphne generator (10) further comprises a distribution line (12), the distribution line (12) having an inlet (14) at one end for the composition to be daphne, and is further connected to each of the inlets of the at least two distributors (18, 18', 18"), preferably the distribution line (12) comprises at least two valves (28), and each of the inlets of the at least two distributors (18, 18', 18") is connected to one of the at least two valves (28). [Claim 7] A davoltaic apparatus (10) according to any one of claims 1 to 6, wherein each of the at least two distributors (18, 18', 18") is positioned above one of the distributors (18, 18', 18") and has a higher pressure loss than the other distributor (18, 18', 18"). [Claim 8] The devolatilization apparatus (10) according to claim 7, wherein the at least one static mixer (26) of the distributor (18, 18', 18") located above another distributor (18, 18', 18") produces a higher pressure loss than the at least one static mixer (26) of the other distributor (18, 18', 18"). [Claim 9] A daphne generator (10) according to any one of claims 1 to 8, wherein each of the at least two distributors (18, 18', 18") is a pipe or comprises an upstream portion that is a pipe, and the pipe of the distributor (18, 18', 18") located above another distributor (18, 18', 18") has a smaller cross-sectional area than the pipe of the other distributor (18, 18', 18"), and / or the pipe of the distributor (18, 18', 18") located above another distributor (18, 18', 18") is longer than the pipe of the other distributor (18, 18', 18"). [Claim 10] A daversion apparatus (10) according to any one of claims 1 to 9, wherein at least one, preferably each, daversion area (20, 20', 20") is provided, which is the area (20, 20', 20") between the top of one distributor (18, 18', 18") and the top of the next lower distributor (18, 18', 18"), or the area (20, 20', 20") between the top of the lowest distributor (18, 18', 18") and the bottom of the container (16), and preferably the uppermost daversion area (20, 20', 20") is provided with more perforated trays (30) than one or more of the lower daversion areas (20, 20', 20"), and preferably the uppermost daversion area (20, 20', 20") is provided with more perforated trays (30) than the lower daversion areas (20, 20', 20"). [Claim 11] The container (16) comprises three distributors (18, 18', 18") and three associated devolatilization zones (20, 20', 20"): a first devolatilization zone (20) between the top of the first uppermost distributor (18) and the top of the second central distributor (18'); a second devolatilization zone (20') between the top of the second central distributor (18') and the top of the third lowermost distributor (18"); and the container (16) between the top of the third lowermost distributor (18") and the container (16) A devolatilization apparatus (10) according to any one of claims 1 to 10, comprising: a third devolatilization area (20") between the bottom of the first devolatilization area (20); three perforated trays (30) arranged in overlapping and spaced apart in the first devolatilization area (20); two perforated trays (30) arranged in overlapping and spaced apart in the second devolatilization area (20'); and one perforated tray (30) in the third devolatilization area (20"). [Claim 12] Each perforated tray (30) has a plurality of openings (32), and each of the openings (32) of a tray (30) has at least substantially the same cross-sectional area, where at least substantially the same cross-sectional area means that each opening (32) has a cross-sectional area of ​​70 to 130%, preferably 80 to 120%, more preferably 90 to 110%, even more preferably 95 to 105%, of the average cross-sectional area of ​​the openings (32) of each tray (30), with the top of one distributor (18, 18', 18") and the next lower distributor (18, 18', 18") The daphne apparatus (10) according to claim 10 or 11, wherein the area between the top of the (20, 20', 20") and the area between the top of the lowest dispensing unit (18") and the bottom of the container (16), and the average cross-sectional area of ​​the opening (32) of a tray (30) located in a daphne area (20, 20', 20") located above another daphne area (20, 20', 20") is smaller than the average cross-sectional area of ​​the opening (32) of a tray (30) located in a lower daphne area (20, 20', 20"). [Claim 13] A polymer preparation plant comprising at least one polymerization reactor, the outlet of at least one of the at least one polymerization reactor, and at least one defoliation device (10) according to any one of claims 1 to 12. [Claim 14] A method for deflorating a composition containing a volatile component, comprising the steps of: supplying the composition to be deflorated to the inlet (14) for the composition to be deflorated of a defloration apparatus (10) according to any one of claims 1 to 11; drawing out a gas from the outlet (24) for gas; and drawing out the deflorated composition from the outlet (22) for the deflorated composition. [Claim 15] The method according to claim 14, wherein the composition to be deflated is selected from the group consisting of polycaprolactone, polyolefin elastomer, polylactic acid, polyglycolic acid, polyolefin, and a mixture or copolymer of two or more of the polymers.

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