Underwater granulation apparatus and method

Abstract

The underwater granulation apparatus comprises a die plate assembly having a molten material inlet for supplying a liquid molten material and a molten material outlet for discharging a plurality of molten strands to an adjacent cutting chamber; a cutting device for generating granulated particles from the molten strands; and a cutting chamber adjacent to the die plate assembly, which is fillable with water or other liquid, and has at least one inlet for supplying water or other liquid to the cutting chamber, and at least one granulated material outlet for discharging a mixture of water or other liquid and granulated material from the cutting chamber. The underwater granulation apparatus also has at least one gas inlet connectable to a gas source for supplying gas directly or indirectly to the cutting chamber so that the supplied gas interacts with the granulated material within the cutting chamber.

Description

Technical Field

[0001] (Cross - reference to related applications) This patent application claims the benefit of the filing of German Patent Application No. 102023119050.4, filed on July 19, 2023, the entire content of which is incorporated herein by reference.

[0002] The present disclosure relates to an underwater granulation apparatus and an underwater granulation method for producing granules or pellets from a resin melt, particularly a polymer melt.

[0003] The present disclosure particularly relates to a granulation apparatus for producing granules from a free - flowing curable resin, comprising a die plate assembly having a melt inlet for supplying a liquid melt and a melt outlet for discharging a plurality of melt strands into an adjacent cutting chamber, a cutting device for generating granule particles from the melt strands, a cutting chamber adjacent to the die plate assembly, which can be filled with water or another liquid and has at least one (water) inlet for supplying water or another liquid into the cutting chamber and at least one (water / ) granule outlet for discharging a mixture of water or another liquid and the granules from the cutting chamber. The present disclosure also relates to the method according to the preamble of claim 9. Water is generally the preferred liquid, but other liquids or mixtures of liquids may also be used.

Background Art

[0004] Granulation apparatuses and methods are known from the prior art, for example, from European Patent Application Publication No. 3711923 or European Patent Application Publication No. 3915747 filed by the present applicant. In such an underwater granulation apparatus, a resin (also called a molten material) that has been made free-flowing by heating is supplied to a die assembly comprising a die plate having multiple fluid channels. The liquid molten material flows through a die plate positioned adjacent to a cutting chamber filled with water. The molten strands flowing out of the holes in the die plate are separated into individual granular particles or pellets made of the molten material by blades that are in contact with the die plate and generally rotating, and discharged into a cutting chamber, also called a "water box". The individual particles come into contact with the water in the cutting chamber, thereby forming a single granular material or pellet that solidifies over time. Water is continuously supplied to the cutting chamber. The pellets are cooled by contact with the water and solidify in the process.

[0005] The pellets thus formed are removed from the cutting chamber by the flow of water in a two-phase flow of water and pellets. International Publication No. 2009 / 155196 proposes introducing air into a transport pipe downstream of the granulator to facilitate the transport of the water and the generated pellets to a centrifugal dryer in order to expedite the removal of the water / pellet mixture from the cutting chamber. After removal, the pellets are separated from the water and dried in a drying process using a drying apparatus. The pellets thus produced are subsequently melted and used, for example, to manufacture resin products in injection molding processes or machinery, or, for example, as a liquid adhesive in manufacturing processes.

[0006] The pellets or granulated particles formed after discharge from the die plate and cutting in the cutting chamber have irregular shapes, ranging from more or less elongated, partially curved, rounded, or elliptical. Often, the goal is to make them closer to spherical, as this offers advantages in terms of packing density, fluidity, and crystallization for transport.

[0007] The purpose of this disclosure is to identify a granulation apparatus and a granulation method for producing pellets or granules in an underwater granulation process, in order to improve the shape of the pellets in the cutting chamber, in particular, such that the pellets produced are substantially spherical in shape.

[0008] This disclosure achieves its objectives through the granulation apparatus described in claim 1 and the method described in claim 9. [Overview of the Initiative]

[0009] In the granulator and similar method according to the present disclosure, at least one gas inlet, connectable to a gas source, is provided for directly or indirectly introducing gas into the cutting chamber, such that the directly or indirectly introduced gas interacts with the granules within the cutting chamber. The gas introduced directly or indirectly into the cutting chamber according to the present disclosure moves through the water within the cutting chamber and interacts with pellets that are initially somewhat free-flowing, released by the die plate assembly and suspended in the water within the cutting chamber (water box), after which the pellets are cooled and solidified. After introduction into the cutting chamber, the gas forms gas bubbles, which typically rise due to buoyancy in the water, thereby moving in addition to the flow of water introduced into and flowing through the cutting chamber. The gas bubbles come into contact with the pellets, influencing the movement of the pellets in the water and potentially mixing in additional movement of the pellets. According to the present disclosure, as an overall result, compared to the prior art, the pellets acquire a rounder, more uniform, and more homogeneous shape within the cutting chamber upon solidification. The size and uniformity of the target circular or elliptical shape of the formed pellets are also suitably influenced by the introduced gas. According to this disclosure, better overall quality of pellets can be achieved in an underwater granulation process as a result of a three-phase flow or movement of gas / water / pellets within a cutting chamber. According to this disclosure, the gas introduced into the cutting chamber makes it possible to produce pellets or granules with better properties. In particular, the gas introduced directly or indirectly into the cutting chamber according to this disclosure makes it possible to make the produced pellets more advantageously compact, especially spherical in shape, or even to ideally achieve a spherical shape. Another advantage of making the pellets more spherical according to this disclosure is that, for example, when polyethylene terephthalate (PET) resin is used, the subsequent crystallization behavior of the pellets is improved, so less energy is required to liquefy the pellets later.The resulting pellets or granules, being closer to a spherical shape, can achieve higher internal heat, and therefore higher crystallinity or higher crystallinity, which is advantageous when further processing the pellets in a resin processing system, particularly during melting. The introduced gas allows the process to run better, even outside of the otherwise optimal operating mode, and also reduces wear between the blade and die plate, or blockage of the nozzle opening in the die plate.

[0010] The gas is preferably air, but other gases or gas mixtures may also be used. The air is preferably supplied from a compressed gas source. Thus, another factor influencing the resin solidification process is provided in the form of the introduced gas, typically in the form of the resulting gas bubbles. The amount of gas introduced into the cutting chamber according to this disclosure, measured, for example, as a volumetric flow rate or mass flow rate, is also used to influence the solidification process in a desired manner, as a further variable in the solidification and formation process of pellets having the best possible quality and homogeneity. According to this disclosure, chemical reactions caused by the gas introduced into the cutting chamber are also possible, such as the reaction of gas molecules with resin molecules. It is also according to this disclosure to introduce, directly or indirectly, other gases or gas mixtures, such as inert gases, argon, nitrogen, etc., preferably of a type that does not react with the molecules contained in the pellets, into the cutting chamber instead of air, either directly or indirectly. As a further alternative, liquids other than water, such as mixtures of water with other liquids, may be introduced directly or indirectly into the cutting chamber.

[0011] According to one embodiment of the granulation apparatus of the present disclosure, a gas nozzle device is provided which has a plurality of nozzle openings for directly or indirectly discharging gas into a cutting chamber and which can be connected to a gas inlet, and the gas nozzle device is positioned directly inside the cutting chamber or inside a (water) supply passage connected to the cutting chamber so that a large number of gas bubbles are formed in the cutting chamber which can be filled with water or other liquid. Such a gas nozzle device can assist in the formation of bubbles, thereby generating, for example, a large number of small gas bubbles, which then vigorously interact with pellet particles in the cutting chamber.

[0012] According to another embodiment, the gas nozzle device is positioned upstream of the outlet of the cutting chamber, preferably directly into or inside the cutting chamber, or indirectly into or inside the (water) supply path, preferably inside the (water) supply pipe. In this way, gas can be introduced into the cutting chamber, either alternatively or cumulatively, directly and / or indirectly. This can form a large number of gas bubbles, which can then vigorously interact with the cutting pellets introduced into the cutting chamber. Due to the buoyancy of the gas, preferably air, in the water flow, the velocity components of the flowing water and the suspended gas are added together, and as a result, the gas bubbles can travel at an increased speed into the area where the pellets are suspended in the water, influencing how the pellets are formed. This can have a further positive effect on the uniformity and quality of the formed pellets. According to this disclosure, the formed pellets come closer to a compact shape, particularly an optimal sphere, although in many cases sphere is merely a goal, and in practice, a perfect sphere is rarely achieved. Experiments have shown that this disclosure achieves an improved approximation to a spherical or compact shape compared to the prior art. According to this disclosure, the sphericity of the pellets increases.

[0013] Therefore, it is preferable that the gas nozzle device be positioned below the die plate assembly.

[0014] Another embodiment of the present disclosure features a gas nozzle device positioned inside a water supply pipe forming a water supply passage, which is preferably substantially vertically oriented and preferably substantially below the die plate assembly, supplying a water / gas mixture to the cutting chamber when in operation. This allows for the concentrated and uniform formation of a large number of gas bubbles in the water-supplied area, thus enabling a strong interaction between the gas bubbles suspended in the water flow and the solidifying pellets. The use of a (water) supply pipe in which the gas nozzle device is positioned results in a very simple design and avoids gas connections in the immediate vicinity of the cutting chamber.

[0015] According to an advantageous development of the present disclosure, in terms of suitable and concentrated mixing of bubbles and pellets, it is proposed that the molten outlet of the die plate assembly be arranged such that the granulated particles and the water / gas mixture move toward each other at least partially, substantially between 60° and 120°, preferably at an angle of about 90°, within the cutting chamber.

[0016] The granulation apparatus is preferably designed such that a water / granule discharge channel for discharging the granule / water / gas mixture is located at the top of the cutting chamber, and the water / granule discharge channel is preferably in the form of a pipe and preferably positioned at least partially substantially vertically to discharge the granule / water / gas mixture during operation and to further transport it for separation and drying of pellets.

[0017] Bubbles can be formed particularly intensively by supplying gas at a high volumetric flow rate and by designing the gas nozzle device as a ring nozzle.

[0018] The advantages described above are also equally achieved by an underwater granulation method for producing granules from a free-flowing curable resin, preferably using the underwater granulation apparatus of the present disclosure, comprising the steps of: supplying a liquid resin in the form of a molten mass to a die plate assembly having a die plate; discharging from the die plate in the form of multiple molten strands through multiple fluid channels in the die plate; dividing the discharged molten strands into individual granule particles by a cutting device; discharging the granule particles into a cutting chamber filled with water or other liquid; introducing water or other liquid into the cutting chamber through at least one (water) inlet; and discharging the water or other liquid and the granules from the cutting chamber through at least one outlet, wherein gas is introduced into the cutting chamber through a gas inlet so that the gas interacts with the granule particles in the cutting chamber filled with water or other liquid. For technical effects and advantages, refer to the above description of the apparatus to avoid repetition.

[0019] Preferably, gas is supplied through a gas inlet to a gas nozzle device connected to the gas inlet and having multiple nozzle openings, and the gas is discharged from the nozzle openings into the cutting chamber so as to form a large number of gas bubbles inside the cutting chamber or inside a (water) supply channel connected to the cutting chamber, and the gas bubbles interact with the granulated particles in the cutting chamber, thereby influencing the shape of the granules or particles during solidification, which can advantageously improve the compactness or sphericity of the pellets.

[0020] Furthermore, it is preferable that the gas is introduced upstream of the outlet of the cutting chamber, preferably directly into or inside the cutting chamber, or indirectly into or via a gas nozzle device located inside a (water) supply passage formed by a (water) supply pipe. The gas nozzle device is located below the die plate assembly, and / or the gas is introduced by the gas nozzle device into a (water) supply pipe that forms a (water) supply passage, which is preferably substantially vertically oriented and preferably located substantially below the die plate assembly, to supply a water / gas mixture to the cutting chamber when in operation.

[0021] In one embodiment, the underwater granulator includes a die plate assembly having a molten inlet for supplying a liquid molten material and a molten outlet for discharging a plurality of molten strands into an adjacent cutting chamber. The underwater granulator further includes a cutting device for producing granulated particles from the molten strands. The underwater granulator further includes a cutting chamber adjacent to the die plate assembly, which is fillable with water or other liquid, and has at least one (water) inlet for supplying water or other liquid into the cutting chamber, and at least one (water) granulated outlet for discharging a mixture of water or other liquid and granules from the cutting chamber. The underwater granulator is also characterized by at least one gas inlet connectable to a gas source for supplying gas directly or indirectly to the cutting chamber so that the supplied gas interacts with the granules within the cutting chamber.

[0022] As described above, specific aspects of this disclosure have been outlined to aid in understanding the detailed description herein and to allow for a more appropriate evaluation of the invention as a contribution to the art. Naturally, there are further aspects of this disclosure described below, which constitute the subject matter of the appended claims.

[0023] In this regard, before explaining at least one aspect of the present disclosure in detail, it should be understood that the present disclosure is not limited to the details of the structures or the arrangements of components described in the following description or drawings. The present disclosure can be implemented and carried out in various ways in addition to what has been described. Also, the expressions and terms, as well as the abstract, used in this specification are for the purpose of explanation and should not be construed as limiting.

[0024] Therefore, those skilled in the art will understand that the underlying concepts of the present disclosure can be readily utilized as a basis for the design of other structures, methods, and systems for achieving the objectives of the present disclosure. Therefore, the claims should be construed to include such corresponding structures insofar as they do not depart from the spirit and scope of the present disclosure.

Brief Description of the Drawings

[0025] The present disclosure will be described with reference to embodiments and the accompanying drawings.

[0026] [Figure 1] It is a schematic view of a first embodiment of a granulating apparatus and a granulating method. [Figure 2] It is a perspective view of a second embodiment of a granulating apparatus. [Figure 3] It is a side view of the granulating apparatus of FIG. 2. [Figure 4] It is an enlarged side view of a part of the granulating apparatus showing gas bubbles. [Figure 5] It is a front view of the granulating apparatus. [Figure 6] It is a partial broken view of the granulating apparatus. [Figure 7] It is a cross-sectional view of a granulating apparatus provided with a gas nozzle device. [Figure 8] It is a partial cross-sectional view of FIG. 7. [Figure 9] It is a cross-sectional view of a granulating apparatus provided with a gas nozzle device according to an alternative embodiment. [Figure 10] It is a partial cross-sectional view of FIG. 9. [Figure 11]This is a cross-sectional view of a granulation apparatus equipped with a gas nozzle device according to another embodiment. [Figure 12] This is a partial cross-sectional view of Figure 11. [Figure 13] This figure shows the granules produced in the first experiment according to the prior art without gas supply. [Figure 14] This figure shows the granules produced by the method of the disclosure in the apparatus of the disclosure in the first experiment. [Figure 15] This figure shows the granules produced in the second experiment according to the prior art without gas supply. [Figure 16] This figure shows the granules produced by the method of the disclosure in the apparatus of the disclosure in the second experiment. [Modes for carrying out the invention]

[0027] The two embodiments shown in Figures 1 and 2-12 each illustrate an (underwater) granulation apparatus 1 and method for producing granules 3 or pellets 3 from a free-flowing curable resin, such as a polymer, and the apparatus is therefore also referred to as a granulator 1. Figures 1 and 4 schematically show a number of pellet particles or granules 3. In the two embodiments, the same reference numerals are used for identical or substantially identical parts and components.

[0028] The granulator 1 shown in Figures 1 and 2 displays a die plate assembly 6 of a type known from the prior art, which typically has a porous disk with multiple cylindrical passages and includes a molten material inlet 8 for supplying liquid molten material and a molten material outlet for discharging multiple molten strands into an adjacent cutting chamber 2. The cutting chamber 2 is also called a water box 2 because it is filled with water that flows through it during operation. Other liquids or fluid mixtures may be used in the apparatus 1 instead of water.

[0029] The cutting device 12, not shown in Figure 1, is shown in Figures 2 to 6 and will be described in more detail with reference to these. The cutting device 12 includes a drive means and a blade rotatable by the drive means and is used to produce individual granules 3 from a molten strand that is discharged from a die assembly 6 having a porous disk to a cutting chamber 2 located adjacent to the die plate assembly 6 and which can be filled with water or other fluid. The cutting chamber 2 is preferably located in the lower region and in this example has (at least) one water inlet 14 for indirectly supplying water to the cutting chamber 2, and is located in the upper region and has (at least) one water / granule outlet 16 for discharging a mixture of water, granules and gas from the cutting chamber. The water inlet 14 of the cutting chamber 2 is coupled to a water supply pipe 38 connected thereto, which forms a water supply passage 36 for supplying water to the cutting chamber 2. An outlet 16 in the upper region of the cutting chamber 2 is connected to a water / granule discharge pipe 18, through which the granules 3 are discharged upward along with water and gas and can be supplied to a separator of a type known to those skilled in the art for separating the produced granules 3 from water, and preferably to a dryer (not shown) for drying the produced granules 3.

[0030] The first example shown in Figure 1, and more specifically in Figures 2 to 11, illustrates an apparatus 1 having at least one gas inlet 19 connectable to a gas source (not shown) for introducing gas into a cutting chamber 2 such that the introduced gas interacts with the granules 3 in the cutting chamber 2, particularly preferably in the form of moving bubbles. In embodiments, the gas inlet 19 is located inside a water supply pipe 38 connected to the cutting chamber 2, and thus the introduced gas is introduced into the cutting chamber 2 indirectly through the supply pipe 38 and then directly through the inlet 14, in this embodiment as a water / gas mixture flowing into the cutting chamber 2 through the water supply pipe 38 and the inlet 14. It is also within the scope of this disclosure that the gas is introduced into the cutting chamber 2 through a gas inlet 19 located inside the cutting chamber 2, or through a gas inlet 19 formed in the wall of the cutting chamber 2, and is introduced from a gas source during operation. The introduced gas is preferably air, which preferably forms a number of gas bubbles introduced into the cutting chamber 2 indirectly by flowing through the supply pipe 38 as shown, or directly as described, where it interacts with the particles of the granules 3.

[0031] Water or other liquid can be supplied upward from the reservoir by a pump through the (water) connection 40, preferably through a vertical supply pipe 39, initially as a single-phase flow indicated by arrow 39, as shown in Figures 1 and 4. The gas inlet 19 is connected to a gas nozzle device 20 having a plurality of nozzle openings 44 for discharging gas into the cutting chamber 2. The gas nozzle device 20 may be located inside the cutting chamber 2 in a manner not shown, or inside a (water) supply passage 36 formed by the supply pipe 38 and connected to the cutting chamber 2, as shown in the embodiment, in either case, a number of gas bubbles 24 are formed in the cutting chamber, preferably filled with water. The gas flow, in the form of bubbles 24, indicated here by arrow 41, flows in a two-phase flow with the supplied water (arrow 39) through the supply pipe 38 and the inlet 19 to the cutting chamber 2, where it may interact with the granules 3 produced. The flow of granules 3, indicated by arrow 43, then flows further upward from the cutting chamber 2 in a three-phase flow (consisting of granule particles, water, and air) along with water and gas, through the outlet 16 and discharge pipe 18, the discharge pipe 18 preferably positioned at least partially vertically for further processing, particularly for the separation and drying of the granules 3.

[0032] Figures 1 and 4-6 show a water / granule discharge channel 17 located at the top of the cutting chamber 2 for discharging the granule / water / gas mixture, which is in the form of a discharge pipe and is preferably positioned at least partially substantially vertically to discharge the granule / water / gas mixture during operation.

[0033] As can be seen particularly from Figures 2 and 3, the apparatus 1 has a mechanical frame 32 which is preferably movable by rollers, on which a cutting device 12 including a rotating blade and a driving means 34 in the form of an electric motor are arranged, as well as a gear transmission connected between the driving means 34 and the blade. The rotating blade is driven by a preferably horizontally positioned shaft 33 (Figures 4 and 6) which extends through the inside of the cutting chamber 2 in a manner known to itself, and the cutting edge of the blade is in contact with a porous disk, which divides the emerging still liquid molten material into particles, and these particles form granules 3 which solidify in water or other liquid in the cutting chamber 2. The shaft 33 that drives the blade is also shown in Figure 6.

[0034] As shown in the embodiment of Figure 1, the cutting chamber 2 is installed within a piping system including a water supply pipe 38 and a water / granule discharge pipe 18, which are each connected to other pipelines. A three-phase flow of water (or other liquid), pellets 3, and gas, particularly air, is formed in the upper discharge pipe 18. As shown in Figures 1 and 4, these three components of the three-phase flow flow in the directions indicated by arrows 39, 41, and 43.

[0035] In a manner not shown, the water connection 40 is connected to a further pipeline to supply water or other liquid from below through the connection 40 using a pump from the storage unit. The discharge pipe 18 can be seen at the top of Figures 2 to 4. The water or other liquid can be reused.

[0036] As is clearly shown in Figures 1 to 4, a gas nozzle device 20 for introducing gas into water or other liquids through a plurality of nozzle openings 44 is located inside the supply pipe 38 downstream of the (water) connection 40. At the same time, the gas nozzle device is located upstream of the outlet 6 of the cutting chamber 2, or directly in or inside the cutting chamber 2 in a manner not shown, or in or inside the water supply passage 36, preferably inside the water supply pipe 38, as shown in the embodiments. In the illustrated embodiments, the gas nozzle device 20 is preferably located in a portion of the pipe 38 that is detachably attached to another portion of the pipe 38. In one embodiment, the nozzle device 20 is located inside the water supply passage 36 connected to the cutting chamber 2, such that gas flows in from the gas inlet 19 and through the inlet 14 into the cutting chamber 2. According to the present disclosure, by introducing gas into the cutting chamber 2 in this manner, or by direct introduction of gas, gas, preferably a number of gas bubbles, are formed in the water-filled cutting chamber 2. The gas nozzle device 20 is located upstream of the water inlet 14 in the area where water is supplied. As can be seen in the diagram, the gas nozzle device 20 is positioned below the die plate assembly 6. As a result, the formed gas bubbles 24 rise upward and reach the area of ​​molten particles discharged from the die assembly 6 into the cutting chamber 2, where these particles form granules 3, which solidify in the water inside the cutting chamber 2 as the process continues.

[0037] As can be seen in Figure 4, the molten outlet of the porous disk of the die plate assembly is arranged so that the granulated particles and the water / gas mixture move toward each other at least partially, substantially between 60° and 120°, preferably at an angle of about 90°, inside the cutting chamber 2. The flow paths inside the porous disk are substantially horizontal, with the molten material flowing into the cutting chamber 2 from right to left, while the (water / )gas mixture flows substantially vertically upward through the inlet 14 into the molten chamber 2 (see also arrows 39 and 41 in Figure 1). Thus, during operation, interaction occurs between the gas bubbles in the water and the particles of the granulated material 3. The mass or volumetric flow rates of water, gas, and molten material can be adjusted and modified by appropriately adjusting the pump, gas supply, and water supply to optimize the production of granulated material 3 in good quality and especially in a compact form.

[0038] As shown in Figure 1, gas is supplied to the gas nozzle device 20 by a pipe 29, preferably arranged horizontally. The pipe 29 is connected to a compressed gas source in a manner not shown. It extends through an opening in the wall of the supply pipe 38. In this embodiment, the openings 44 of the gas nozzle device 20, which are located inside the supply pipe or directly in the cutting chamber 2, are used to release gas from the nozzle device 20 into water or other liquids and ultimately into the cutting chamber 2 (see also Figures 8–12). The openings 44 may be arranged in annular, linear, or any random pattern. Figures 6 and 10 show how the nozzle device 20 is designed as a ring nozzle having multiple openings 44 located in a circle.

[0039] The cross-sectional view in Figure 6 shows a supply pipe 38 in which a gas nozzle device 20, designed as a ring nozzle with multiple openings 44, is located. The gas, along with water, flows into the cutting chamber 2 from the inlet 14. Granules in the form of particles formed using the nozzle device 6 and the cutting device 12 are also supplied to the cutting chamber, where the granules 3 come into contact with water and gas, particularly gas bubbles 24. The mixture of granules 3, water, and gas flows out of the cutting chamber 2 through the outlet 16 and pipe 18.

[0040] Figures 7 and 8 show the gas nozzle device 20 and the pipe 29 (pipeline 29) for supplying gas / air from the compressed gas source to the nozzle device 20. The gas is supplied through pipe 29 into the interior of the supply pipe 38 section.

[0041] Figures 9 and 10 show that the gas nozzle device 20 can be designed as a ring nozzle having multiple openings 44 so that a large number of gas bubbles are formed in the water flow.

[0042] Figures 11 and 12 show an alternative embodiment of the nozzle device 20. Here, multiple through-holes with openings 44 are formed in the wall of a section of the (water) supply pipe 38, and gas is supplied into the interior of the supply pipe 38 through these openings. To this end, the pipe 29 is connected to an annular space 46 (Figure 12), and the gas can flow out from the annular space 46 through the openings 44 into the interior of the supply pipe 38.

[0043] The above-mentioned figure also illustrates the underwater granulation method according to the present disclosure for producing granules 3 from a free-flowing curable resin, the method preferably performed using a granulator 1. A liquid resin in the form of a molten material is supplied to a die plate assembly 6 having a die plate and discharged from the die plate in the form of multiple molten strands through multiple fluid channels within the die plate. A cutting device 12 having at least one rotating blade generates a number of individual particles in the die plate that form the granules. The granule particles are discharged into a cutting chamber 2 (water box) filled with water or other liquid. Water or other liquid is supplied to the cutting chamber 2 via at least one (water) inlet 14. Gas is supplied to the cutting chamber 2 directly or indirectly via a supply path 36 from a gas inlet 19. The gas supplied to the cutting chamber 2 interacts with the granule particles within the cutting chamber 2 filled with water or other liquid. The water or other liquid, the granules 3, and the gas are transported out of the cutting chamber 2 via at least one outlet 17. The gas is preferably supplied via a gas inlet 19 to a gas nozzle device 20 connected thereto, which has a plurality of nozzle openings 44. The gas exiting the nozzle openings 44 pre-forms a number of gas bubbles 24 inside the cutting chamber 2 or inside a (water) supply passage 36 connected to the cutting chamber 2. According to one embodiment, the gas is introduced into the (water) supply passage 36 by the gas nozzle device 20, which is preferably substantially vertically oriented and preferably located substantially below the die plate assembly 6, and supplies a (water / )gas mixture to the cutting chamber 2 when in operation.

[0044] In accordance with this disclosure, it is preferable that the gas, preferably compressed air, is supplied continuously. Continuous supply of gas is understood here to mean that the volumetric or mass flow of the gas is constant, and various flow rates are possible, i.e., different volumetric or mass flow rates can be set. However, alternatively, in the method of this disclosure using the apparatus of this disclosure, it is also possible to supply the gas at a variable volumetric or mass flow rate. For example, it is also possible to supply the gas intermittently in accordance with this disclosure, i.e., to turn the gas supply on during a particular phase and pause it during a different phase. To those skilled in the art, it is reasonable to implement continuous, variable, discontinuous, or intermittent gas supply. For example, the gas supply can be changed or different volumetric or mass flow rates can be adjusted by switching each valve on or off and / or by each throttle valve. Those skilled in the art will understand that the gas, in particular air, may be supplied from a gas source such as a compressed gas system. The gas supply can be controlled and regulated by appropriately controlling the apparatus.

[0045] Figure 13 shows a schematic diagram of resin granules 3 manufactured according to the prior art. Figure 14 shows resin granules 3 manufactured using the apparatus 1 according to the disclosure and under similar manufacturing conditions according to the manufacturing method according to the disclosure. Figures 13 and 14 show the different results without gas supply according to the disclosure (Figure 13) and with gas supply according to the disclosure (Figure 14).

[0046] In this experiment, the following parameters were set: experimental setup as shown in the embodiment in Figure 1, mass flow rate of molten resin: 150 kg / hour, process water temperature: 60°C.

[0047] Highly irregular granule shape (Figure 13): Figure 13 shows that particles manufactured according to prior art are elongated, and in some cases compact, far from the ideal spherical shape. The ratio of the minimum length of the particles to the maximum length is far from a value of 1. A value of 1 is achieved in an ideal sphere.

[0048] With gas supply according to this disclosure: with a mass flow rate of molten resin of 150 kg / hour, a process water temperature of 60°C, and a 10% gas supply of compressed air, the shape of the granules is significantly improved in that they are more compact, rounder, and closer to spherical (Figure 14). From the particle shape in Figure 14 (according to this disclosure), it can be seen that the particles are closer to spherical and more compact with the gas supply according to this disclosure compared to Figure 13 (related to the prior art). The ratio of the minimum width to the maximum length is close to the ideal spherical value of 1.

[0049] Figure 15 shows a schematic diagram of resin granules 3 manufactured according to the prior art. Figure 16 shows resin granules manufactured using the apparatus 1 according to the present disclosure under similar manufacturing conditions according to the manufacturing method according to the present disclosure.

[0050] Figures 15 and 16 show the different results of the present disclosure without gas supply (Figure 15) and with gas supply (Figure 16). In this experiment, the following parameters were set: experimental setup as shown in the embodiment of Figure 1, mass flow rate of molten resin: 200 kg / hour, process water temperature: 50°C. This results in a highly irregular granule shape (Figure 15).

[0051] With gas supply as described in this disclosure: with a mass flow rate of molten resin of 200 kg / hour, a process water temperature of 50°C, and 50% gas supply by compressed air, there is little change in the shape of the granules (Figure 16), however, it is clear that the shape of the granules becomes more rounded and closer to a sphere.

[0052] Measurements show that the sphericity of granule 3 is improved by the gas supply according to this disclosure (Figure 16). The sphericity is improved here from 0.661 to 0.765 (1.0 represents a spherical shape). Sphericity is determined here by calculating the quotient obtained by dividing the minimum particle length by the maximum particle length.

[0053] The surface area of ​​individual granules also decreases, thus showing a positive change toward a spherical shape.

[0054] A comparison between Figures 13 and 15 (prior art) and Figures 14 and 16 (present disclosure) shows that supplying gas to the process water according to the present disclosure affects the shape of the granules formed during the solidification process. According to the present disclosure, the interaction of gas bubbles in the process water within the region of the cutting chamber 2 during the solidification of granule particles leads to an improvement in the quality of the granules 3, resulting in granules that are more compact and closer to spherical than those in the prior art.

[0055] (Explanation of symbols) 1 Underwater granulation equipment 2. Cutting chamber (water box) 3. Granules or pellets (particles) 6 Die Plate Assembly 7 Die Plates 8. Molten material inlet 10 Molten material outlet 12 Cutting device 14 (Wed) Entrance 16 (Water / ) Granule outlet 17 (Water / ) Granule discharge channel 18 (Water / ) Granule discharge pipe 19 Gas Inlet 20 Gas nozzle device 24 Gas bubbles 29 tube 31 Transmission Gear 32 Machine Frames 33 Drive shaft 34. Driving means (cutting device) 35 blades 36 (Wed) Supply route 38 (Water) Supply pipe 39 Arrows indicating the direction of water flow 40 (Water) Connection 41 Arrows indicating the direction of gas flow 43 Arrows indicating the direction of granulation logistics 44 Nozzle openings 46 Circular Space

[0056] One embodiment: The underwater granulator includes a die plate assembly having a molten inlet for supplying a liquid molten material and a molten outlet for discharging a plurality of molten strands into an adjacent cutting chamber. The underwater granulator further includes a cutting device for producing granulated particles from the molten strands. The underwater granulator further includes a cutting chamber adjacent to the die plate assembly, which is fillable with water or other liquid and has at least one (water) inlet for supplying water or other liquid into the cutting chamber, and at least one (water) granulated outlet for discharging a mixture of water or other liquid and granules from the cutting chamber. The underwater granulator is also characterized by at least one gas inlet connectable to a gas source for supplying gas directly or indirectly to the cutting chamber so that the supplied gas interacts with the granules in the cutting chamber.

[0057] The embodiments described above may further include one or more combinations of the following embodiments: a granulator of the embodiments described above, characterized in that it has a plurality of nozzle openings for directly or indirectly discharging gas into a cutting chamber, and is provided with a gas nozzle device connectable to a gas inlet, wherein the gas nozzle device is positioned directly inside the cutting chamber or inside a (water) supply channel connected to the cutting chamber, such that a plurality of gas bubbles are formed in the cutting chamber, which can be filled with water or other liquid. According to another embodiment, the granulator of the embodiments described above, characterized in that the gas nozzle device is positioned upstream of the outlet of the cutting chamber, preferably directly in or inside the cutting chamber, or indirectly in or inside the (water) supply channel, preferably inside the (water) supply pipe. The granulator of the embodiments described above, characterized in that the gas nozzle device is positioned below the die plate assembly. The granulator of the embodiments described above, characterized in that the gas nozzle device is positioned inside a water supply pipe forming a water supply channel, which is preferably substantially vertically oriented and preferably substantially below the die plate assembly, and supplies a water / gas mixture to the cutting chamber when in operation.

[0058] One embodiment: The underwater granulator includes a die plate assembly having a molten inlet for supplying a liquid molten material and a molten outlet for discharging a plurality of molten strands into an adjacent cutting chamber. The underwater granulator further includes a cutting device for producing granulated particles from the molten strands. The underwater granulator further includes a cutting chamber adjacent to the die plate assembly, which is fillable with water or other liquid and has at least one inlet for supplying water or other liquid into the cutting chamber, and at least one granulated outlet for discharging a mixture of water or other liquid and granulated material from the cutting chamber. The underwater granulator also includes at least one gas inlet connectable to a gas source for supplying gas directly or indirectly to the cutting chamber so that the supplied gas interacts with the granulated material within the cutting chamber.

[0059] The embodiments described above may further include one or more combinations of the following embodiments: a granulator of the above embodiment having a plurality of nozzle openings for directly or indirectly discharging gas into a cutting chamber, and provided with a gas nozzle device connectable to a gas inlet, wherein the gas nozzle device is positioned directly inside the cutting chamber or inside a supply path connected to the cutting chamber so as to form a plurality of gas bubbles in the cutting chamber, which can be filled with water or other liquid; a granulator of the above embodiment, wherein the gas nozzle device is positioned upstream of the outlet of the cutting chamber; a granulator of the above embodiment, wherein the gas nozzle device is positioned upstream of the outlet of the cutting chamber, directly in or inside the cutting chamber, or indirectly in or inside a supply path; a granulator of the above embodiment, wherein the gas nozzle device is positioned upstream of the outlet of the cutting chamber, directly in or inside the cutting chamber, or indirectly in or inside a supply path inside a supply pipe; a granulator of the above embodiment, wherein the gas nozzle device is positioned below the die plate assembly. The granulator of the above embodiment, wherein a gas nozzle device is located inside a water supply pipe forming a water supply passage, the water supply passage is preferably oriented substantially vertically and preferably located substantially below the die plate assembly to supply a water / gas mixture to the cutting chamber during operation. The granulator of the above embodiment, wherein the molten outlet of the die plate assembly is arranged such that the granulated particles and the water / gas mixture move toward each other at least partially at an angle of substantially 60° to 120°, preferably at an angle of about 90°, inside the cutting chamber. The granulator of the above embodiment, wherein the gas nozzle device is in the form of a ring nozzle. The granulator of the above embodiment, wherein a water / granulated discharge passage for discharging the granulated mixture and / or water mixture is located above the cutting chamber, the water / granulated discharge passage is preferably in the form of a pipe and preferably oriented at least partially substantially vertically to discharge the granulated mixture, water mixture, and / or gas mixture during operation.A method for underwater granulation according to the above-described embodiment, preferably using a granulation apparatus, wherein a liquid resin in the form of a molten material is supplied to a die plate assembly having a die plate, discharged from the die plate in the form of multiple molten strands through multiple fluid channels in the die plate, the discharged molten strands are divided into individual granular particles by a cutting device, the granular particles are discharged into a cutting chamber filled with water or other liquid, water or other liquid is introduced into the cutting chamber through at least one inlet, the water or other liquid and the granules are discharged from the cutting chamber through at least one outlet, and gas is introduced into the cutting chamber through a gas inlet so that the gas interacts with the granular particles in the cutting chamber filled with water or other liquid. The underwater granulation method of the above embodiment, wherein gas is supplied via a gas inlet to a gas nozzle device connected to the gas inlet and having a plurality of nozzle openings, and the gas is discharged from the nozzle openings into the cutting chamber so as to form a number of gas bubbles inside the cutting chamber or inside a supply path connected to the cutting chamber, and the gas bubbles interact with granulated particles in the cutting chamber, thereby affecting the shape of the granulated material or particles during solidification. The underwater granulation method of the above embodiment, wherein gas is introduced through a nozzle device downstream of the inlet in the region where water is supplied, and the gas nozzle device is preferably located below the die plate assembly. A method according to at least one of the preceding embodiments.

[0060] In this specification, terms such as "First," "Second," etc., are used to describe various elements, but these elements are not limited by these terms. These terms are used solely to distinguish one element from another. For example, without departing from the scope of disclosure, the First element may be called the Second element, and similarly, the Second element may be called the First element. In this specification, the term "and / or" includes any combination of one or more items from the relevant enumerated items.

[0061] When an element such as a layer, region, or substrate is described as being located "on" or extending "onto" another element, that element may be located directly on or extend directly onto the other element, or an intermediate element may exist between them. On the other hand, when an element is described as being located "directly on" or extending "directly onto" another element, there is no intermediate element. Similarly, when an element such as a layer, region, or substrate is described as being located "over" or extending "over" another element, that element may be located directly over the other element, extend directly onto it, or an intermediate element may exist between them. On the other hand, when an element is described as being located "directly over" or extending "directly over" another element, there is no intermediate element. When an element is described as being "connected" or "coupled" to another element, that element may be directly connected or coupled to the other element, or an intermediate element may exist between them. On the other hand, when elements are described as "directly connected" or "directly coupled," there are no intermediate elements.

[0062] Relative terms such as "below," "above," "upper," "lower," "horizontal," and "vertical" are used to describe the relationship between one element, layer, or region and another, as shown in the diagram. It should be understood that these terms, and those mentioned above, are intended to include different orientations of the apparatus in addition to the orientation shown in the diagram.

[0063] The terms used herein are for the purpose of describing specific aspects and are not intended to limit the scope of the disclosure. In this specification, singular forms such as “a,” “an,” and “the” are to be interpreted as including plural forms unless the context clearly indicates otherwise. Furthermore, the terms “comprises,” “comprising,” “includes,” and “including” are used herein to identify the presence of described features, integers, steps, actions, elements, and / or components, but should not be constrained by the existence or addition of one or more other features, integers, steps, actions, elements, components, and / or groups thereof.

[0064] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as those generally understood by those skilled in the art to the extent of this disclosure. Furthermore, terms used herein should be construed to be consistent with their meanings in the context of this specification and in the relevant art, and should not be interpreted in an idealized or overly formal sense unless expressly defined so.

[0065] Many of the features and advantages of this disclosure will become apparent from the detailed description. Accordingly, the attached claims are intended to encompass all the features and advantages of this disclosure that are included in the spirit and scope of this disclosure. Furthermore, since many modifications and changes are readily conceivable to those skilled in the art, this disclosure is not limited to the exact configuration or operation illustrated or described, and therefore all suitable variations and equivalents within the scope of this disclosure are included therein.

Claims

1. An underwater granulation apparatus for producing granules from a freely flowing curable resin, A die plate assembly having a molten material inlet for supplying liquid molten material and a molten material outlet for discharging multiple molten strands to an adjacent cutting chamber, A cutting device for generating granulated particles from the molten strand, A cutting chamber adjacent to the die plate assembly, which can be filled with water or other liquid, having at least one (water) inlet for supplying water or other liquid to the cutting chamber, and having at least one (water) granule outlet for discharging a mixture of water or other liquid and granules from the cutting chamber, An underwater granulation apparatus having at least one gas inlet connectable to a gas source for supplying gas directly or indirectly to the cutting chamber so that the supplied gas interacts with the granulated material within the cutting chamber.

2. A gas nozzle device is provided, having multiple nozzle openings for directly or indirectly discharging gas into the cutting chamber, and connectable to the gas inlet. The underwater granulation apparatus according to claim 1, characterized in that the gas nozzle device is positioned directly inside the cutting chamber, or inside a (water) supply channel connected to the cutting chamber, such that a large number of gas bubbles are formed inside the cutting chamber, which can be filled with water or other liquid.

3. The underwater granulation apparatus according to claim 2, characterized in that the gas nozzle device is positioned upstream of the outlet of the cutting chamber, preferably directly in or inside the cutting chamber, or indirectly in or inside the (water) supply path, preferably inside the (water) supply pipe.

4. The underwater granulation apparatus according to claim 2 or 3, characterized in that the gas nozzle device is positioned below the die plate assembly.

5. The underwater granulation apparatus according to any one of claims 2 to 4, wherein the gas nozzle device is located inside a (water) supply pipe forming the (water) supply passage, the (water) supply passage is preferably oriented substantially vertically and preferably located substantially below the die plate assembly, and supplies a water / gas mixture to the cutting chamber when in operation.

6. The underwater granulation apparatus according to any one of claims 1 to 5, characterized in that the molten outlet of the die plate assembly is arranged such that the granulated particles and the water / gas mixture move toward each other at least partially, substantially at an angle of 60° to 120°, preferably at an angle of about 90°, inside the cutting chamber.

7. An underwater granulation apparatus according to any one of claims 1 to 6, characterized in that a water / granule discharge channel for discharging a granule ( / water) mixture is located above the cutting chamber, the water / granule discharge channel is preferably in the form of a pipe, and preferably is positioned at least partially substantially vertically to discharge a granule / water / gas mixture during operation.

8. The underwater granulation apparatus according to any one of claims 1 to 7, characterized in that the gas nozzle device is in the form of a ring nozzle.

9. A method for producing granules from a freely flowable curable resin using underwater granulation, preferably using an underwater granulation apparatus as described in any one of claims 1 to 8. A liquid resin in the form of a molten material is supplied to a die plate assembly having a die plate, and discharged from the die plate in the form of multiple molten strands through multiple fluid channels within the die plate. The discharged molten strand is divided into individual granulated particles by a cutting device. The granulated particles are discharged into a cutting chamber filled with water or other liquid. Water or other liquid is introduced into the cutting chamber through at least one (water) inlet. Water or other liquid and granules are discharged from the cutting chamber through at least one outlet. A method for underwater granulation, characterized by introducing a gas into a cutting chamber via a gas inlet so that the gas interacts with granulated particles in the cutting chamber, which is filled with water or other liquid.

10. Through the gas inlet, gas is supplied to a gas nozzle device having a plurality of nozzle openings connected to the gas inlet. The method according to claim 9, characterized in that the gas is discharged from the nozzle opening into the cutting chamber such that a large number of gas bubbles are formed inside the cutting chamber or inside the (water) supply channel connected to the cutting chamber, and the gas bubbles interact with the granulated particles inside the cutting chamber, thereby affecting the shape of the granulated material or particles during solidification.

11. The method according to claim 9 or 10, characterized in that gas is introduced via the nozzle device downstream of the (water) inlet in the region where water is supplied, and the gas nozzle device is preferably located below the die plate assembly.

12. The method according to any one of claims 9 to 11, characterized in that gas is introduced by the gas nozzle device into a (water) supply pipe forming the (water) supply passage, the (water) supply passage is preferably substantially vertically oriented and preferably substantially below the die plate assembly, and supplies a water / gas mixture to the cutting chamber when in operation.

13. An underwater granulation apparatus for producing granules from a freely flowing curable resin, A die plate assembly having a molten material inlet for supplying liquid molten material and a molten material outlet for discharging multiple molten strands to an adjacent cutting chamber, A cutting device for generating granulated particles from the molten strand, A cutting chamber adjacent to the die plate assembly, which can be filled with water or other liquid, and which has at least one inlet for supplying water or other liquid to the cutting chamber, and at least one granule outlet for discharging a mixture of water or other liquid and granules from the cutting chamber, An underwater granulation apparatus having at least one gas inlet connectable to a gas source for supplying gas directly or indirectly to the cutting chamber so that the supplied gas interacts with the granules within the cutting chamber.

14. A gas nozzle device is provided, having multiple nozzle openings for directly or indirectly discharging gas into the cutting chamber, and connectable to the gas inlet. The underwater granulation apparatus according to claim 13, wherein the gas nozzle device is positioned directly inside the cutting chamber or inside a supply path connected to the cutting chamber, so as to form a large number of gas bubbles inside the cutting chamber, which can be filled with water or other liquid.

15. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is positioned upstream of the outlet of the cutting chamber.

16. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is disposed upstream of the outlet of the cutting chamber, directly in or inside the cutting chamber, or indirectly in or inside the supply path.

17. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is disposed upstream of the outlet of the cutting chamber, directly in or inside the cutting chamber, or indirectly in or inside the supply passage inside the supply pipe.

18. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is located below the die plate assembly.

19. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is arranged inside the water supply pipe that forms the water supply path.

20. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is arranged inside a water supply pipe forming the water supply passage, and the water supply passage is substantially oriented vertically.

21. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is located inside a water supply pipe forming the water supply passage, the water supply passage is substantially vertically oriented and located substantially below the die plate assembly, and supplies a water / gas mixture to the cutting chamber when in operation.

22. The underwater granulator according to claim 19, wherein the molten outlet of the die plate assembly is arranged such that the granulated particles and the water / gas mixture move toward each other at least partially, substantially between 60° and 120°, within the cutting chamber.

23. The underwater granulator according to claim 19, wherein the molten outlet of the die plate assembly is arranged such that the granulated particles and the water / gas mixture move toward each other at least partially, substantially at an angle of about 90°, within the cutting chamber.

24. The underwater granulation apparatus according to claim 13, wherein a water / granule discharge channel for discharging a granule mixture and / or a water mixture is located above the cutting chamber.

25. The underwater granulation apparatus according to claim 13, wherein a water / granule discharge channel for discharging a granule mixture and / or water mixture is located above the cutting chamber, and the water / granule discharge channel is in the form of a pipe.

26. The underwater granulation apparatus according to claim 13, wherein a water / granule discharge channel for discharging a granule mixture and / or a water mixture is located above the cutting chamber, and the water / granule discharge channel is in the form of a pipe and is positioned at least partially substantially vertically for discharging the granule mixture, water mixture and / or gas mixture during operation.

27. The underwater granulation apparatus according to claim 14, wherein the gas nozzle device is in the form of a ring nozzle.

28. An underwater granulation method for producing granules from a freely flowing curable resin, using the underwater granulation apparatus described in claim 13, A liquid resin in the form of a molten material is supplied to a die plate assembly having a die plate, and discharged from the die plate in the form of multiple molten strands through multiple fluid channels within the die plate. The discharged molten strand is divided into individual granulated particles by a cutting device. The granulated particles are discharged into a cutting chamber filled with water or other liquid. Water or other liquid is introduced into the cutting chamber through at least one inlet. Water or other liquid and granules are discharged from the cutting chamber through at least one outlet. A method of underwater granulation, comprising introducing a gas into a cutting chamber via a gas inlet so that the gas interacts with granulated particles in the cutting chamber, which is filled with water or other liquid.

29. Through the gas inlet, gas is supplied to a gas nozzle device having a plurality of nozzle openings connected to the gas inlet. The underwater granulation method according to claim 28, wherein the gas is discharged from the nozzle opening into the cutting chamber such that a large number of gas bubbles are formed inside the cutting chamber or inside the supply passage connected to the cutting chamber, and the gas bubbles interact with the granulated particles in the cutting chamber, thereby affecting the shape of the granulated material or particles when solidified.

30. The underwater granulation method according to claim 28, wherein gas is introduced via a nozzle device downstream of the inlet in the region where water is supplied.

31. The underwater granulation method according to claim 28, wherein gas is introduced via a nozzle device downstream of the inlet in the region where water is supplied, and the gas nozzle device is positioned below the die plate assembly.

32. The underwater granulation method according to claim 28, wherein gas is introduced into a supply pipe forming the supply path by a gas nozzle device.

33. The method for granulating water underwater according to claim 28, wherein gas is introduced by a gas nozzle device into a supply pipe forming the supply passage, and the supply passage is substantially oriented vertically.

34. The underwater granulation method according to claim 28, wherein gas is introduced by a gas nozzle device into a supply pipe forming the supply passage, the supply passage being substantially vertically oriented and positioned substantially below the die plate assembly, and supplying a water / gas mixture to the cutting chamber when in operation.

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