Devolving apparatus with perforated roof elements

Abstract

The present invention relates to a defloration apparatus for deflorating compositions having volatile components, such as for deflorating solid or liquid polymer compositions having unreacted monomers, solvents, and / or by-products. The defloration apparatus has a container having at least one inlet for the composition to be deflored, at least one outlet for the deflored composition, at least one outlet for the gas, and at least one tray, the at least one tray having a perforated bottom element, at least one baffle disposed on the perforated bottom element and separating the perforated bottom element into at least one internal area having one or more openings and at least one external area having one or more openings, and at least one perforated roof element having one or more openings and disposed above at least a portion of the internal area of ​​the perforated bottom element. At least one weir is positioned on the outer edge of the perforated bottom element, the inlet is located above at least one perforated roof element, the area of ​​the projection surface of at least one perforated roof element is 100-150% of the surface area of ​​at least one internal area of ​​the perforated bottom element, and the opening of at least one external area of ​​the perforated bottom element has a larger cross-sectional area than the opening of at least one internal area of ​​the perforated bottom element and the opening of at least one perforated roof element.

Description

[Technical Field]

[0001] The present invention relates to a devolatilization apparatus for defolatilizing compositions containing volatile components, such as for defolatilizing solid or liquid polymer compositions having unreacted monomers and solvents, and to a devolatilization process using such a devolatilization apparatus. [Background technology]

[0002] Devolatilization, or degassing, refers to the controlled removal of gases and other volatile substances such as solvents or water from solids and liquids, respectively. Devolatilization is typically used to remove volatile components, which are mostly components with relatively low molecular weights, such as residual monomers from polymers, solvents, reaction by-products, and water. 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 into articles, components that degrade the polymer's properties, components that cause unpleasant odors in the polymer, and / or components that are undesirable for other reasons. Furthermore, by removing monomers and solvents from the polymer composition, it becomes possible to recover and potentially recycle monomers and solvents during the process to increase process yield 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 have 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 gaseous 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 has 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 defollation 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 composition to be devolatilized, such as polymers, the devolatilizer is preferably suitable for use in devolatilizing a wide range of compositions, specifically compositions with relatively high viscosity and compositions with relatively low viscosity. 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 therefore 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.

[0008] To overcome this problem, it has already been proposed to install two types of internal structures in the devolatilization apparatus: one for devolatilizing low-viscosity compositions and the other for devolatilizing high-viscosity compositions. Such a devolatilization apparatus has an inlet line that splits into a secondary inlet line for low-viscosity compositions and a secondary inlet line for high-viscosity compositions, and a valve through which the composition to be devolatilized can be guided to either the secondary inlet line for low-viscosity compositions or the secondary inlet line for high-viscosity compositions. Thus, depending on the specific devolatilization application, the polymer feed to be devolatilized is directed to either the internal structure for devolatilizing high-viscosity compositions or the internal structure for devolatilizing low-viscosity compositions. However, such devolatilization apparatuses are expensive, and only a portion of the internal structure is used while devolatilizing high-viscosity polymers, resulting in an extremely low yield per unit volume of the devolatilization apparatus. [Prior art documents] [Patent Documents]

[0009] [Patent Document 1] International Publication No. 2010 / 066457 (A1) [Patent Document 2] European Patent Application Publication No. 1206962 (A1) [Patent Document 3] European Patent No. 2158027 (B1) [Patent Document 4] European Patent No. 0655275 (B1) [Patent Document 5] U.S. Patent No. 3,743,250 (A) [Patent Document 6] European Patent No. 2548634 (B1) [Patent Document 7] European Patent No. 0815929 (B1) [Patent Document 8] European Patent No. 1510247 (B1) [Patent Document 9] U.S. Patent No. 4,093,188 (A) [Patent Document 10] U.S. Patent No. 4,296,779 (A) [Summary of the Invention] [Problems to be Solved by the Invention]

[0010] From this point, the fundamental object of the present invention is to provide a devolatilization apparatus for devolatilizing a composition having volatile components, such as for devolatilizing a solid or liquid polymer composition having unreacted monomers, solvents, and / or by-products. The devolatilization apparatus enables not only a high-viscosity composition having a kinematic viscosity of at least 1,000 Pa·s but also a low-viscosity composition having a kinematic viscosity of less than 1,000 Pa·s, particularly less than 500 Pa·s, to be devolatilized in a compact design with high efficiency and low operating costs. [Means for Solving the Problems]

[0011] According to the present invention, a defoliation apparatus for defoliating a composition having volatile components, such as for defoliating a solid or liquid polymer composition having unreacted monomers, solvents, and / or by-products, the defoliation apparatus having a container having at least one inlet for the composition to be defoliated, at least one outlet for the defoliated composition, at least one outlet for the gas, and at least one tray, wherein the at least one tray has a perforated bottom element and at least one baffle disposed on the perforated bottom element, separating the perforated bottom element into at least one internal area having one or more openings and at least one external area having one or more openings, This objective is satisfied by providing a daphragm having at least one perforated roof element having one or more openings and positioned above at least a portion of the internal area of ​​a perforated bottom element, wherein at least one weir is positioned on the outer edge of the perforated bottom element, the inlet is located above the at least one perforated roof element, the area of ​​the projected surface of the at least one perforated roof element is 100-150% of the surface area of ​​the at least one internal area of ​​the perforated bottom element, and the opening of the at least one external area of ​​the perforated bottom element has a larger cross-sectional area than the opening of the at least one internal area of ​​the perforated bottom element and the opening of the at least one perforated roof element.

[0012] Viewed in the horizontal direction, by dividing the perforated bottom element of one or more trays of the devolatilization device into at least one internal area and at least one external area, and by arranging a perforated roof element above at least one internal area of the perforated bottom element, where the openings of at least one external area have a cross-sectional area larger than the openings of at least one internal area and the openings of at least one perforated roof element, one or more trays are suitable for use in the devolatilization of high-viscosity compositions and the devolatilization of low-viscosity compositions. During operation, the composition to be devolatilized is led onto the perforated roof element. If the composition to be devolatilized has a sufficiently low viscosity such that it enters and passes through the openings of the perforated roof element, the composition falls onto the surface of at least one internal area of the perforated bottom element and enters and passes through the openings of at least one internal area of the perforated bottom element. However, if the composition to be devolatilized has a high viscosity, due to which the composition to be devolatilized cannot enter and pass through the openings of the perforated roof element, the composition flows over the perforated roof element and falls onto the surface of at least one external area of the perforated bottom element and enters and passes through the openings of at least one external area of the perforated bottom element. Overall, the devolatilization device according to the present invention has the advantage of a compact design and enables the devolatilization of compositions over a wide viscosity range efficiently and at low operating costs.

[0013] The term "perforated roof element" is used herein to refer to any kind of perforated element. The term "roof" is used only to easily distinguish this element from other elements of the devolatilization device without intending to structurally limit this element.

[0014] According to the present invention, at least one external area of the perforated bottom element, at least one internal area of the perforated bottom element, and at least one perforated roof element each have one or more openings. This means that according to the present invention, the openings extend through the perforated bottom element and the perforated roof element respectively, thereby enabling liquid to flow from the upper side of the perforated bottom element and the perforated roof element through the openings to the opposite lower side.

[0015] According to the present invention, at least one of the trays of the daphne apparatus has a perforated bottom element. The perforated bottom element may be formed from a single perforated bottom plate. Alternatively, the perforated bottom element may have two or more perforated bottom plates that are adjacent to each other and fixed to each other to form the perforated bottom element. When the perforated bottom element has two or more perforated bottom plates, each perforated bottom plate is preferably connected to each other in a fluid-seal manner, so that the liquid can flow through the perforated bottom element only through the openings of the perforated bottom plates and not through the gaps between adjacent perforated bottom plates.

[0016] The present invention is not specifically limited with respect to the shape and size of each perforated bottom element or one or more perforated bottom plates. Good results can be achieved, for example, when one or more perforated bottom plates have a polygonal, rectangular, square, circular, elliptical, or trapezoidal shape when viewed from the top. However, it is preferable that the perforated bottom element has a rectangular, pentagonal, or hexagonal shape when viewed from the top. Furthermore, when the perforated bottom element has two or more perforated bottom plates, it is preferable that a single perforated bottom plate has a rectangular or half-trapeze shape when viewed from the top, for example, that some of the perforated bottom plates have a rectangular shape and the others have a half-trapeze shape. Most preferably, the perforated bottom element has a hexagonal shape when viewed from the top, and the hexagonal shape is formed from one perforated bottom plate, or from two or more perforated bottom plates, each independently having a rectangular or half-trapeze shape.

[0017] Furthermore, there are no specific limitations on the material of each perforated bottom element or one or more perforated bottom plates, as long as the material is resistant to the composition to be volatilized and is mechanically stable. It is also preferable that the material of the perforated bottom plates has relatively good thermal conductivity. Particularly good results are obtained when each of the one or more perforated bottom plates is made from stainless steel, carbon steel, Hastelloy, etc.

[0018] The preferred thickness of the perforated bottom element, or one or more perforated bottom plates, depends on the mechanical stability of the material from which each is made. Good results can be obtained, for example, when the thickness of the perforated bottom element, or each of the one or more perforated bottom plates, is 1 to 30 mm, more preferably 5 to 15 mm.

[0019] According to a particularly preferred embodiment of the present invention, at least one baffle fluidly seals at least one internal area from at least one external area of ​​the perforated bottom element.

[0020] In this context, the term baffle refers to any wall and is therefore equivalent to a partition wall. Fluid-seal separation of at least one internal area from at least one external area means that fluid cannot flow through one or more baffles from any of the at least one internal area to any of the at least one external area of ​​the perforated bottom element, and vice versa. In other words, if at least one tray has two or more baffles, all baffles are preferably connected to one or more internal areas to fluid-seal separation of any of the one or more internal areas from any or more external areas. Furthermore, all one or more baffles are preferably non-perforated.

[0021] The present invention is not specifically limited to the material of at least one baffle, as long as that material is resistant to the composition to be deflated and mechanically stable. Particularly good results are obtained when each at least one baffle is made from stainless steel, carbon steel, Hastelloy, etc. Particularly preferably, at least one baffle is made from the same material as the perforated bottom element.

[0022] Preferably, at least one baffle extends at least substantially vertically upward from the surface of the perforated bottom element, and being at least substantially vertical means that the angle between at least one baffle and the vertical direction is at most 10°, preferably at most 5°, more preferably at most 1°, and most preferably 0°. The vertical direction is the direction perpendicular to the plane of the perforated bottom element.

[0023] Further development of the concept of the present invention suggests that each of the one or more baffles may have a thickness of 1 to 30 mm, more preferably 5 to 15 mm.

[0024] In addition, it is preferable that each of the one or more baffles has a height of 100 to 1,000 mm, more preferably 300 to 500 mm.

[0025] According to a particularly preferred embodiment of the present invention, at least one tray has one baffle having a hollow cylindrical shape, or at least one tray has four baffles. Each of the four baffles is connected on each side to another of the four baffles such that, when viewed from above, all four baffles form a hollow rectangle or hollow square shape, thereby surrounding the rectangular or square internal area of ​​the perforated bottom element.

[0026] In the above-described embodiment, it is even more preferable that the perforated bottom element has a hexagonal shape when viewed from the top, and that the hollow cylindrical baffle or the four baffles are arranged such that the center point of the internal area surrounded by each of the hollow cylindrical baffle or the four baffles is also the center point of the hexagon. In other words, the internal areas are preferably arranged concentrically around the center point of the perforated bottom element.

[0027] The present invention is not specifically limited with respect to the shape of at least one perforated roof element. Particularly good results are obtained when at least one perforated roof element has the shape of a hollow dome, hollow cone, hollow pyramid, hollow frustum of a cone, or hollow frustum of a pyramid.

[0028] As described above, the function of at least one perforated roof element is to guide the composition to be deflated in dependency of its viscosity, that is, if the viscosity is relatively low, to guide it through the openings of the perforated roof element to the surface of at least one internal area of ​​the perforated bottom element, or if the viscosity is relatively high, to guide it along the peripheral region of the perforated roof element to the surface of at least one external area of ​​the perforated bottom element. For this reason, it is preferable that at least one perforated roof element covers the entire area or at least substantially the entire area of ​​at least one internal area of ​​the perforated bottom element. Accordingly, according to the present invention, the area of ​​the projected surface of at least one perforated roof element is substantially the same as the surface area of ​​at least one internal area of ​​the perforated bottom element, where substantially the same area means that the area of ​​the projected surface of at least one perforated roof element region is 100 to 150%, preferably 100 to 130%, more preferably 100 to 110%, even more preferably 100 to 105%, and most preferably equal to the surface area of ​​at least one internal area of ​​the perforated bottom element. The term "projection plane of a perforated roof element" refers to the base region, or ground region, of the perforated roof element.

[0029] Further developments of the present invention suggest that the peripheral region of at least one perforated bottom element is moderately inclined with respect to the horizontal plane so that, depending on its viscosity, the composition to be deflated, such as a polymer melt, is prevented from flowing along the peripheral region to the surface of at least one external region of the perforated bottom element rather than flowing through the opening of the perforated roof element to the surface of at least one internal region of the perforated bottom element due to gravity, even when the composition to be deflated, such as a polymer melt, flows through the opening of the perforated roof element to the surface of at least one internal region of the perforated bottom element, rather than flowing along the peripheral region to the surface of at least one external region of the perforated bottom element, even when the viscosity is low. In this regard, the angle between the peripheral region of at least one perforated roof element and the horizontal plane is preferably 1° to 60°, preferably 10° to 45°, and more preferably 15° to 30°. For example, at least one perforated roof element has the shape of a hollow cone, hollow pyramid, hollow frustum of a cone, or hollow frustum of a pyramid, and the angle between the peripheral region of at least one perforated roof element and the horizontal plane is 1° to 60°, preferably 10° to 45°, more preferably 15° to 30°.

[0030] Good results are particularly obtained when at least one perforated roof element has a height of 3 to 300 cm, more preferably 10 to 150 cm. Here, height refers to the vertical distance between the lower projection plane and the highest point of the perforated roof element.

[0031] At least one perforated roof element is preferably positioned on top of at least one baffle surrounding at least one internal area of ​​the perforated bottom element, or at a distance above at least one baffle surrounding at least one internal area of ​​the perforated bottom element, such that at least one perforated roof element covers up to 150%, preferably up to 130%, more preferably up to 110%, even more preferably up to 105%, and most preferably all of the surface area of ​​at least one internal area of ​​the perforated bottom element. In the latter case, where at least one perforated roof element is positioned at a distance above at least one internal area of ​​the perforated bottom element, it is preferable that the perforated roof element is connected to one or more baffles by one or more connecting means, each of which may be in the form of a bar.

[0032] According to a particularly preferred embodiment of the present invention, the tray has a perforated bottom element having a hexagonal shape when viewed from the top, and four non-perforated baffles are arranged on the surface of the perforated bottom element such that they form a hollow rectangle or hollow square arranged around the center point of the perforated bottom element, thereby fluidly sealing the perforated bottom element into one rectangular or square internal area and an external area, and a perforated roof element having the shape of a hollow dome, hollow cone, or hollow pyramid is positioned on top of the four non-perforated baffles or above the four non-perforated baffles and is connected to the four non-perforated baffles by one or more connecting bars.

[0033] According to an alternative, particularly preferred embodiment of the present invention, the tray has a perforated bottom element having a hexagonal shape when viewed from the top, a hollow cylindrical baffle is positioned on the surface of the perforated bottom element such that it forms a cylinder arranged around the center point of the perforated bottom element, thereby fluidly sealing the perforated bottom element into one circular inner section and an outer section, and a perforated roof element having the shape of a hollow dome, hollow cone, or hollow pyramid is positioned on top of or above the four non-perforated baffles and is connected to the four non-perforated baffles by one or more connecting bars.

[0034] The present invention is not specifically limited in terms of the relative sizes of the internal and external regions of the perforated bottom element. Good results are obtained when the ratio of the surface area of ​​at least one internal region to the total surface area of ​​the perforated bottom element is 20-70%, preferably 30-50%. The total surface area of ​​the perforated bottom element is the sum of the area of ​​at least one internal region and the area of ​​at least one external region.

[0035] According to the present invention, each of the at least one internal region of the perforated bottom element, each of the at least one external region of the perforated bottom element, and each of the at least one perforated roof element have openings. All of the openings in the at least one internal region of the perforated bottom element may have the same shape and the same cross-sectional area, or they may differ in their shape and / or cross-sectional area. Similarly, all of the openings in the at least one external region of the perforated bottom element may have the same shape and the same cross-sectional area, or they may differ in their shape and / or cross-sectional area. In the same way, all of the openings in the at least one perforated roof element may have the same shape and the same cross-sectional area, or they may differ in their shape and / or cross-sectional area. If all the openings in each region or element have the same cross-sectional area, then all the openings in the at least one external region of the perforated bottom element have a larger cross-sectional area than all the openings in the at least one internal region of the perforated bottom element and all the openings in the at least one perforated roof element. If the cross-sectional areas of the openings in each section or element differ, the average cross-sectional area of ​​the openings in at least one external section of the perforated bottom element is greater than the average cross-sectional area of ​​the openings in at least one internal section of the perforated bottom element, and also greater than the average cross-sectional area of ​​the openings in at least one perforated roof element. The average cross-sectional area of ​​the openings in a single section or element is the sum of the cross-sectional areas of all the openings in that section or element divided by the total number of openings in that section or element.

[0036] The present invention is not specifically limited with respect to the cross-sectional shape of the opening in at least one internal area of ​​the perforated bottom element, the cross-sectional shape of the opening in at least one external area of ​​the perforated bottom element, and the cross-sectional shape of the opening in at least one perforated roof element. For example, part or preferably all of the opening in at least one internal area of ​​the perforated bottom element, part or preferably all of the opening in at least one external area of ​​the perforated bottom element, and part or preferably all of the opening in at least one perforated roof element may have a polygonal, rectangular, square, circular, elliptical, or trapezoidal cross-sectional shape. More preferably, at least part, most preferably all, of the opening in at least one internal area of ​​the perforated bottom element, at least part, most preferably all, of the opening in at least one external area of ​​the perforated bottom element, and at least part, most preferably all, of the opening in at least one perforated roof element may have a circular cross-sectional shape.

[0037] Furthermore, it is preferable that all openings in at least one internal region of the perforated bottom element have at least substantially the same cross-sectional area. In addition, it is preferable that all openings in at least one external region of the perforated bottom element have at least substantially the same cross-sectional area, and as described above, the (average) cross-sectional area of ​​the openings in at least one external region of the perforated bottom element is larger than the (average) cross-sectional area of ​​the openings in at least one internal region of the perforated bottom element. Similarly, it is preferable that all openings in at least one perforated roof element have at least substantially the same cross-sectional area, and as described above, the (average) cross-sectional area of ​​the openings in at least one perforated roof element is smaller than the (average) cross-sectional area of ​​the openings in at least one external region of the perforated bottom element. In this context, "at least substantially the same cross-sectional area" means that each opening in each region or element differs from the average cross-sectional area of ​​all openings in each region or element by 70% or less, more preferably 40% or less, even more preferably 10% or less, and most preferably 1% or less, respectively, and has no different cross-sectional area at all. In this case as well, the average cross-sectional area of ​​all openings is the sum of the cross-sectional areas of all openings in each area or element divided by the total number of openings in each area or element.

[0038] According to the present invention, the opening of at least one external area of ​​the perforated bottom element has a larger cross-sectional area than the opening of at least one internal area of ​​the perforated bottom element and the opening of at least one perforated roof element. Particularly good results are obtained when the average cross-sectional area of ​​the opening of at least one external area of ​​the perforated bottom is at least 50%, preferably at least 125%, more preferably at least 300%, even more preferably at least 1,500%, even more preferably at least 3,000%, and most preferably at least 6,300% larger than the average cross-sectional area of ​​the opening of at least one internal area of ​​the perforated bottom and the average cross-sectional area of ​​the opening of at least one perforated roof element.

[0039] A particularly good result is obtained when all openings in at least one external area of ​​the perforated bottom have the same cross-sectional area, all openings in at least one internal area of ​​the perforated bottom have the same cross-sectional area, all openings in at least one perforated roof element have the same cross-sectional area, and the cross-sectional area of ​​the opening in at least one external area of ​​the perforated bottom is at least 50%, preferably at least 125%, more preferably at least 300%, even more preferably at least 1,500%, even more preferably at least 3,000%, and most preferably at least 6,300% larger than the cross-sectional area of ​​the opening in at least one internal area of ​​the perforated bottom and the cross-sectional area of ​​the opening in at least one perforated roof element.

[0040] In further development of the concept of the present invention, it is preferable that all openings in at least one external area of ​​the perforated bottom have a circular cross-sectional shape and the same diameter, all openings in at least one internal area of ​​the perforated bottom have a circular cross-sectional shape and the same diameter, all openings in at least one perforated roof element have a circular cross-sectional shape and the same diameter, and the diameter of the opening in at least one external area of ​​the perforated bottom is at least 25%, preferably at least 50%, more preferably at least 100%, even more preferably at least 300%, and most preferably at least 700% larger than the diameter of the opening in at least one internal area of ​​the perforated bottom and the diameter of the opening in at least one perforated roof element.

[0041] According to a further particularly preferred embodiment of the present invention, the cross-sectional area of ​​the opening of at least one perforated roof element is the same as, or at least substantially the same as, the cross-sectional area of ​​the opening of at least one internal area of ​​the perforated bottom element. In this regard, it is preferable that the average cross-sectional area of ​​the opening of at least one perforated roof element is 70 to 130%, preferably 80 to 120%, more preferably 90 to 110%, and even more preferably 95 to 105% of the average cross-sectional area of ​​the opening of at least one internal area of ​​the perforated bottom element. Most preferably, the average cross-sectional area of ​​the opening of at least one perforated roof element is the same as the average cross-sectional area of ​​the opening of at least one internal area of ​​the perforated bottom element.

[0042] In this case as well, particularly good results are obtained when all openings of at least one perforated roof element have the same cross-sectional area, all openings of at least one internal area of ​​the perforated bottom have the same cross-sectional area, and the cross-sectional area of ​​the opening of at least one perforated roof element is 70-130%, preferably 80-120%, more preferably 90-110%, even more preferably 95-105%, and most preferably equal to the cross-sectional area of ​​the opening of at least one internal area of ​​the perforated bottom element.

[0043] In further development of the concept of the present invention, it is preferable that all openings of at least one perforated roof element have a circular cross-sectional shape and the same diameter, all openings of at least one internal area of ​​the perforated bottom have a circular cross-sectional shape and the same diameter, and the diameter of the opening of at least one external area of ​​the perforated bottom is 70 to 130%, preferably 80 to 120%, more preferably 90 to 110%, even more preferably 95 to 105%, and most preferably equal to the diameter of the opening of at least one internal area of ​​the perforated bottom element.

[0044] The average cross-sectional area of ​​the opening in at least one external area of ​​the perforated bottom element is preferably at least 3 cm². 2 , more preferably at least 5 cm 2 More preferably, at least 10 cm 2and on the other hand, the average cross-sectional area of the openings in at least one internal region of the perforated bottom element and the average cross-sectional area of the openings in at least one perforated roof element are at most 10 cm 2 , preferably at most 5 cm 2 , more preferably at most 3 cm 2 In this case, particularly good results are obtained. Preferably, the average cross-sectional area of the openings in at least one external region of the perforated bottom element is at most 80 cm 2 , more preferably at most 50 cm 2 , even more preferably at most 30 cm 2 and on the other hand, the average cross-sectional area of the openings in at least one internal region of the perforated bottom element and the average cross-sectional area of the openings in at least one perforated roof element are at least 0.2 cm 2 , more preferably at least 0.7 cm 2 , even more preferably at least 1 cm 2 .

[0045] Also in this case, particularly good results are obtained when all the openings of at least one perforated roof element have the same cross-sectional area, all the openings of at least one internal region of the perforated bottom have the same cross-sectional area, and all the openings of at least one external region of the perforated bottom have the same cross-sectional area. In this embodiment, the cross-sectional area of the openings in at least one external region of the perforated bottom element is preferably at least 3 cm 2 , more preferably at least 5 cm 2 , even more preferably at least 10 cm 2 and on the other hand, the cross-sectional area of the openings in at least one internal region of the perforated bottom element and the cross-sectional area of the openings in at least one perforated roof element are preferably at most 10 cm 2 , more preferably at most 5 cm 2 , even more preferably at most 3 cm 2 . Preferably, the cross-sectional area of the openings in at least one external region of the perforated bottom element is at most 80 cm 2 , more preferably at most 50 cm 2 , even more preferably at most 30 cm 2On the other hand, the cross-sectional area of ​​the opening of at least one internal area of ​​the perforated bottom element and the cross-sectional area of ​​the opening of at least one perforated roof element are preferably at least 0.2 cm². 2 , more preferably at least 0.7 cm 2 More preferably, at least 1 cm 2 That is the case.

[0046] Favorable results are particularly obtained when all openings in at least one external area of ​​the perforated bottom have a circular cross-section and the same diameter, all openings in at least one internal area of ​​the perforated bottom have a circular cross-section and the same diameter, and all openings in at least one perforated roof element have a circular cross-section and the same diameter. In this embodiment, the diameter of the opening in at least one external area of ​​the perforated bottom element is preferably at least 20 mm, more preferably at least 30 mm, and even more preferably at least 40 mm, while the diameter of the opening in at least one internal area of ​​the perforated bottom element and the diameter of the opening in at least one perforated roof element are preferably up to 30 mm, more preferably up to 25 mm, and even more preferably up to 20 mm. Preferably, the diameter of the opening in at least one external area of ​​the perforated bottom element is a maximum of 100 mm, more preferably a maximum of 80 mm, and even more preferably a maximum of 60 mm, while the diameter of the opening in at least one internal area of ​​the perforated bottom element and the cross-sectional area of ​​the opening in at least one perforated roof element are preferably at least 5 mm, more preferably at least 10 mm, and even more preferably at least 15 mm.

[0047] According to the present invention, at least one weir is positioned on the outer edge of the perforated bottom element. Preferably, at least one weir extends at least substantially vertically upward from the surface of the perforated bottom element. Preferably, at least one weir surrounds the perforated bottom element in a fluid-seal manner so that the liquid contained on the surface of the perforated bottom element cannot flow out of the perforated bottom element. In this case as well, being at least substantially vertical means that the angle between at least one weir and the vertical direction is at most 10°, preferably at most 5°, more preferably at most 1°, and most preferably 0°.

[0048] Favorable results are particularly obtained when at least one weir is 10-100 cm high, more preferably 20-50 cm high.

[0049] The present invention is not specifically limited with respect to the type of at least one inlet for the composition to be deflated. For example, the at least one inlet for the composition to be deflated is an opening in an inlet line, and that inlet line may be a pipe.

[0050] According to the present invention, the inlet is located above at least one perforated roof element. Particularly good results are achieved when the inlet is located above the center point of at least one perforated roof element and spaced away from the center point of at least one perforated roof element.

[0051] Depending on the amount of composition to be devolatilized per period and the surface area of ​​the perforated bottom element of at least one tray, the devolatilization apparatus has one tray or two or more trays. When the devolatilization apparatus has two or more trays, preferably all trays are embodied as described above, and all trays are arranged overlapping and spaced apart. For example, the devolatilization apparatus has one tray or two to ten trays, more preferably two to five trays, and most preferably two trays.

[0052] In further development of the concept of the present invention, it is suggested that a preheater element be positioned upstream of at least one inlet for the composition to be devolatiled. This makes it possible to temperature-control (temperate) the composition to be devolatiled to a suitable temperature. The preheater element may be any known heating element, such as a tubular heat exchanger with mixing elements, a heat exchanger with mixing bundles, or a plate-frame heat exchanger, particularly for low-viscosity fluids. For example, at least one inlet for the composition to be devolatiled is an opening in an inlet line, and that inlet line is connected (preferably directly) upstream of the inlet to a preheater element.

[0053] In a further particularly preferred embodiment of the present invention, at least one static mixer is positioned upstream of at least one inlet for the composition to be deflated. This allows for mixing the composition to be deflated, i.e., a gas-liquid mixture, which has volatile components, in order to enhance the mass transfer of volatile substances from the bulk liquid to the liquid surface and to maximize the gas-liquid interaction surface during the operation of the defloration apparatus.

[0054] A static mixer is a mixer that has no moving parts, and in particular no rotating parts. More specifically, according to the present invention, a static mixer is defined as a stationary device that includes at least two deflection means, not openings, orifices, for mixing a one-phase or two-phase fluid flow, preferably continuously. Preferably, the static mixer has 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, it is preferable that the at least two deflection means are 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, it is preferable that the static mixer has 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, static mixers are designed to achieve mixing effects for single-phase and even two-phase fluid flows that flow in layers. Static mixers draw energy for mixing the fluid flow from the fluid itself and do not require any 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 has 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 / 066457(A1), European Patent Application Publication No. 1206962(A1), European Patent No. 2158027(B1), and European Patent No. 0655275(B1), 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 Nos. 2548634(B1) and 0815929(B1). Baffle plate type static mixers typically have longitudinal deflection means and are described, for example, in European Patent No. 1510247(B1) and U.S. Patent No. 4,093,188(A), while turbulator strip type static mixers have 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.

[0055] Good results can be obtained, for example, if at least one inlet for the composition is an opening in an inlet line, and that inlet line is connected (preferably directly) to at least one static mixer upstream of that inlet.

[0056] More preferably, the inlet line, when viewed upstream, is first connected (preferably directly) to one or more static mixers, and further upstream, (preferably directly) to a preheater element.

[0057] In addition, the distributor may be located upstream of the above-mentioned inlet, in which case the above-mentioned inlet is the outlet of the distributor.

[0058] In another aspect, the present invention relates to a method for defoliating a composition having volatile components, comprising the steps of supplying a composition to be defoliated to the inlet of a defoliation apparatus, drawing out (removing) gas from a gas outlet, and drawing out the defoliated composition from an outlet for defoliated compositions.

[0059] The present patent application will then be described by reference to advantageous embodiments and the accompanying drawings. [Brief explanation of the drawing]

[0060] [Figure 1] This is a schematic longitudinal cross-sectional view of a daphne apparatus according to one embodiment of the present invention. [Figure 2] Figure 1 is a perspective view of the two trays included in the thawing device shown. [Figure 3a] This figure shows one of four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 3b] This figure shows one of four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 3c] This figure shows one of four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 3d] This figure shows one of four different types of static mixers that can be used in the devolatilization apparatus and method according to the present invention. [Figure 3e] This figure shows one of 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]

[0061] The defoliation apparatus 10 shown in Figure 1, for defoliating compositions containing volatile components, such as solid or liquid polymer compositions having unreacted monomers, solvents, and / or by-products, has a container 12 having at least one inlet 14 for the composition to be defoliated, at least one outlet 16 for the defoliated composition, at least one outlet 18 for the gas, and at least two trays 20, 20' arranged to overlap and be spaced apart.

[0062] Each of the two trays 20, 20' has a perforated bottom element 22, four baffles 24 positioned on the perforated bottom element 22 and separating the perforated bottom element 22 into an internal area 26 having one or more openings and an external area 28 having one or more openings 30, a perforated roof element 32 and a weir 36. The weir 36 is positioned on the outer edge of the perforated bottom element 22 and oriented vertically upward, while the perforated roof element 32 has a pyramidal shape and has one or more openings 34 on its peripheral wall, is positioned above the internal area 26 of the perforated bottom element 22 and is connected to the four baffles 24 by four bars 37. Each of the four baffles 24 is connected on each side to another of the four baffles 24, so that when viewed from above, all four baffles 24 form a hollow square shape, thereby surrounding the square interior area 26 of the perforated bottom element 22. The opening 30 of the exterior area 28 of the perforated bottom element 22 has a larger cross-sectional area than the opening of the interior area 26 of the perforated bottom element 22 and the opening 34 of the perforated roof element 32. Furthermore, the davoltizer 10 has an inlet line 38 connected to the preheater element 40 and downstream thereto connected to the static mixer 42, the downstream end of the static mixer 42 forming an inlet 14.

[0063] During operation, the composition to be defolazed is supplied to the inlet 42 via the inlet line 38, passing through the preheating element 40 and the static mixer 42, from where it falls to the center point of the pyramidal perforated roof element 32. If the composition to be defolazed has a viscosity low enough to enter and pass through the opening 34 of the perforated roof element 32, it falls onto the surface of the internal area 26 of the perforated bottom element 22, enters and passes through the opening of the internal area 26 of the perforated bottom element 22. However, if the composition to be defolazed has a high viscosity, it is unable to enter and pass through the opening 34 of the perforated roof element 32, and instead flows along the peripheral wall of the perforated roof element 32, falls onto the surface of the external area 28 of the perforated bottom element 22, enters and passes through the opening 30 of the external area 28 of the perforated bottom element 22. Overall, the devolatilization apparatus 10 according to the present invention is characterized by its compact design, enabling efficient and low-cost devolatilization of compositions with a wide viscosity range.

[0064] Figure 3 shows five different types of static mixers usable in the devolatilization apparatus and method according to the present invention, namely, Figure 3a shows an X-type static mixer 42 having a crossbar-shaped deflection means 44 having an X-shape in both plan and side views. Figure 3b shows a baffle plate-type static mixer 42 having a longitudinal deflection means 44, while Figures 3c and 3d show static mixers 42 having a curved deflection means 44. Figure 3e shows a combined static mixer and heat transfer element 46 having a tubular deflection means 44, which is distributed by Sulzer Chemtech Ltd under the trade name SMR, and is formed to function as a heat transfer element by transporting a heat transfer medium within a tube, and at the same time function as a static mixer for a liquid transported to the outside of the tubular deflection means 44. [Explanation of Symbols]

[0065] 10 Devolatilization equipment 12 containers 14 Entrance 16. Outlet for defoliated composition 18 Gas outlet 20 trays 20' Tray 22 Perforated bottom element 24 baffles 26 Internal area of ​​perforated bottom element 28. External area of ​​perforated bottom element 30 Openings in the exterior area 32 Perforated roof elements 34 Openings of perforated roof elements 36 Weir 37 Bar 38 Entrance Line 40 Preheater elements 42 Static mixer 44 Static mixer deflection means 46 Heat transfer elements of a static mixer

Claims

1. A defoliation apparatus (10) for defoliating a composition having volatile components, such as for defoliating a solid or liquid polymer composition having unreacted monomers, solvents, and / or by-products, The defoliation apparatus (10) has a container (12), the container (12) has at least one inlet (14) for the composition to be defoliated, at least one outlet (16) for the defoliated composition, at least one outlet (18) for the gas, and at least one tray (20, 20'), The at least one tray (20, 20') comprises a perforated bottom element (22), at least one baffle (24) disposed on the perforated bottom element (22), the baffle (24) separating the perforated bottom element (22) into at least one internal area (26) having one or more openings and at least one external area (28) having one or more openings (30), and at least one perforated roof element (32) having one or more openings (34) and disposed above at least a portion of the internal area (26) of the perforated bottom element (22), At least one weir (36) is positioned on the outer edge of the perforated bottom element (22), The entrance is located above the at least one perforated roof element (32), The area of ​​the projection surface of at least one perforated roof element (32) is 100 to 150% of the surface area of ​​at least one internal area (26) of the perforated bottom element (22), and A defoliation device (10), wherein the opening (30) of the at least one external region (28) of the perforated bottom element (22) has a larger cross-sectional area than the opening of the at least one internal region (26) of the perforated bottom element (22) and the opening (34) of the at least one perforated roof element (32).

2. The daphne generator (10) according to claim 1, wherein the perforated bottom element (22) has one perforated bottom plate or at least two perforated bottom plates arranged adjacent to each other.

3. The devolatilization apparatus (10) according to claim 1 or 2, wherein the at least one baffle (24) fluidly seals the at least one internal area (26) from the at least one external area (28) of the perforated bottom element (22).

4. The daphne generator (10) according to any one of claims 1 to 3, wherein the at least one baffle (24) extends at least substantially vertically upward from the surface of the perforated bottom element (22), and at least substantially vertical means that the angle between the at least one baffle (24) and the vertical is at most 10°, preferably at most 5°, more preferably at most 1°, and most preferably 0°.

5. The daphne generator (10) according to any one of claims 1 to 4, wherein the at least one tray (20, 20') has one hollow cylindrical baffle or four baffles, and each of the four baffles is connected on each side thereof to another of the four baffles (24), so that when viewed from above, all four baffles (24) form a hollow rectangle or a hollow square shape.

6. The devolatilization device (10) according to claim 5, wherein the perforated bottom element (22) has a hexagonal shape when viewed from the top, and the one hollow cylindrical baffle is arranged such that the center point of the circular internal area (26) is also the center point of the hexagon, or the four baffles (24) are arranged such that the center points of the rectangular or square internal area (26) are also the center points of the hexagon.

7. The daphne generator (10) according to any one of claims 1 to 6, wherein the at least one perforated roof element (32) has the shape of a hollow dome, a hollow cone, a hollow pyramid, a hollow frustum of a cone, or a hollow frustum of a pyramid.

8. The daphne generator (10) according to any one of claims 1 to 7, wherein the area of ​​the projection surface of the at least one perforated roof element (32) is 100 to 130%, preferably 100 to 110%, more preferably 100 to 105%, and most preferably the same as the surface area of ​​the at least one internal area (26) of the perforated bottom element (22).

9. The daphne generator (10) according to any one of claims 1 to 8, wherein the at least one perforated roof element (32) has the shape of a hollow cone, a hollow pyramidal

10. The average cross-sectional area of the openings (30) of the at least one external region (28) of the perforated bottom is at least 50%, preferably at least 125%, more preferably at least 300%, even more preferably at least 1,500%, even more preferably at least 3,000%, and most preferably at least 6,300% larger than the average cross-sectional area of the openings of the at least one internal region (26) of the perforated bottom and the average cross-sectional area of the openings (34) of the at least one perforated roof element (32). The devolatilization device (10) according to any one of claims 1 to 9.

11. The average cross-sectional area of the openings (34) of the at least one perforated roof element (32) is 70 to 130%, preferably 80 to 120%, more preferably 90 to 110%, even more preferably 95 to 105%, and most preferably the same as the average cross-sectional area of the openings (30) of the at least one internal region (26) of the perforated bottom element (22). The devolatilization device (10) according to any one of claims 1 to 10.

12. All of the openings (30) of the at least one external region (28) of the perforated bottom have the same cross-sectional area and circular cross-sectional shape, all of the openings of the at least one internal region (26) of the perforated bottom have the same cross-sectional area and circular cross-sectional shape, and all of the openings (34) of the at least one perforated roof element (32) have the same cross-sectional area and circular cross-sectional shape. The diameter of the openings (30) of the at least one external region (28) of the perforated bottom element (22) is at least 20 mm, preferably at least 30 mm, more preferably at least 40 mm, while the diameter of the openings of the at least one internal region (26) of the perforated bottom element (22) and the diameter of the openings (34) of the at least one perforated roof element (32) are at most 30 mm, preferably at most 25 mm, more preferably at most 20 mm. The devolatilization device (10) according to any one of claims 1 to 11.

13. The at least one weir (36) extends at least substantially vertically upward from the surface of the perforated bottom element (22). The angle between the at least one weir (36) and the vertical direction is at most 10°, preferably at most 5°, more preferably at most 1°, and most preferably 0°. Preferably, the daphne generator (10) according to any one of claims 1 to 12, wherein the at least one weir (36) surrounds the perforated bottom element (22) in a fluid-seal manner so that the liquid contained on the surface of the perforated bottom element (22) cannot flow out of the perforated bottom element (22).

14. The daphne generator (10) according to any one of claims 1 to 13, wherein the at least one inlet (14) for the composition is an opening in an inlet line (38), the inlet is located above the center point of the at least one perforated roof element (32) and is spaced apart from the center point of the at least one perforated roof element (32).

15. The daphne generator (10) according to any one of claims 1 to 14, wherein the at least one inlet (14) for the composition is an opening in an inlet line (38), and the inlet line (38) is directly connected upstream of the inlet (14) to a preheater element (40) and / or at least one static mixer (42).

16. A method for defolazing a composition having a volatile component, comprising the steps of: supplying the composition to be defolazed to the inlet of a defolazing apparatus (10) according to any one of claims 1 to 15; removing gas from the outlet (18) for gas; and removing the defolazed composition from the outlet (16) for the defolazed composition.

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