WO2014048649A1

WO2014048649A1 - Device for heating or cooling a meltable material

Info

Publication number: WO2014048649A1
Application number: PCT/EP2013/067571
Authority: WO
Inventors: Ralf BUCH; Waldemar MÜNCH; Robert Rupaner
Original assignee: Basf Se
Priority date: 2012-09-26
Filing date: 2013-08-23
Publication date: 2014-04-03
Also published as: BR112015005118A2; CN104640621A; AU2013323054A1; EP2900361A1

Abstract

The invention relates to a device for heating or cooling a meltable material in a container, comprising a heating element (10) and a holding device (20), wherein the heating element (10) is designed to be tubular, having an inlet opening (11) and an outlet opening (12) for the flow of a thermal transfer medium, and is fastened movably, in at least one spatial direction, as the primary movement direction, to the holding device (20), characterized in that the device furthermore has an agitator (30) for mixing liquid material, which is likewise movably arranged in the primary movement direction.

Description

The invention relates to a device for heating or cooling a fusible material in a container comprising a heating element and a holding device, wherein the heating element tubular configured with an inlet opening and a drain opening for flow with a heat transfer medium and in at least a spatial direction as the main movement direction is movably attached to the holding device. Furthermore, the invention relates to a method for melting a fusible material and a method for cooling a molten material in a container having on its upper side an opening, by means of a device according to the invention.

Several feedstocks for the chemical or other processing industries, such as waxes, wax-like oligomers and polymers, fats, emulsifiers or salts, are included

Ambient temperature (20 ° C to 25 ° C) in solid or highly viscous state and must be liquefied before further processing. The provision of larger amounts of such substances is associated with some effort. Transport and delivery of such materials are usually carried out in transport containers such as drums or containers, e.g. The so-called "intermediate bulk containers" (IBC), which can usually have a capacity of 500 to 1000 liters depending on the design.The containers have on its top a filling opening of about 15 cm in diameter and a drain cock on the ground of the container.

Since the starting materials often constitute a mixture, it is generally necessary to melt and homogenize the entire contents of a transport container before a homogeneous subset can be removed from the transport container and sent for further processing, since it can be assumed that the preceding solidification process, the components are crystallized at different rates and therefore the mixture is not homogeneously distributed in the container.

The liquefaction of the contents of a transport container is often carried out in so-called heat cabinets, wherein the container are placed in a closed, tempered room in which it is heated as a whole by the surrounding air. In another established method for melting the container contents, the container is immersed in a basin of hot water and left there until the container contents have melted. Both the warming cabinet and the plunge pool are associated with complex construction measures and have a high energy consumption. Furthermore, electrically operated heating bands and heating jackets are known, which are placed around the outer wall of the transport container and transfer heat to the container wall. They too are not very energy efficient.

Another disadvantage of the above-mentioned method is the fact that the heat transfer takes place indirectly via the container wall. As a wall material for IBC, for example, in usually polyethylene (HDPE) used, which has a low thermal conductivity and a thermal resistance of about 100 ° C. This limits the warm-up process with regard to the maximum permissible temperature, in order to avoid damage or even destruction of the container wall. In addition, in the case of wall heating, the layers of the solid near the wall first melt, so that gas layers form between the solid and the inner wall of the container in the course of the melting process, which further reduce the thermal conductivity.

Especially for barrels as a transport container devices are known in which a warm- ing does not take place indirectly over the barrel wall, but in direct contact with the material to be melted. In the published patent application DE 37 06 927 A1 a barrel melting device is described, which comprises a horizontally arranged pipe spiral, which is flowed through by superheated steam. The pipe spiral is placed on the material to be melted and slides in a holder with the progress of the melting process under the influence of gravity in the barrel down.

The document RU 2 159 671 C1 discloses a similar device, which is also intended for the liquefaction of solid, meltable drum contents. Also in this device, a horizontally arranged pipe spiral is placed on the material to be melted and slides with progressive melting process in the barrel down. The pipe spiral is traversed by a liquid heating medium whose temperature is adjustable.

While the two aforementioned devices are capable of liquefying the contents of barrels, they are only of limited use for melting material in a container such as an IBC. Because unlike barrels in which the opening cross-section is the same order of magnitude as the barrel cross-section, the openings of containers are usually much smaller than the container cross-section. Although vertical channels can melt into the material in a container with the mentioned devices, it takes a very long time until the entire material is liquefied, if this is even possible.

The object was to provide a device with which solid or highly viscous materials can be liquefied in transport containers in a short time, homogeneous and energy efficient. This object is achieved by a device for heating a fusible material in a container comprising a heating element and a holding device, wherein the heating element tubular configured with an inlet opening and a drain opening for flow with a heat transfer medium and movable in at least one spatial direction as the main movement direction on the holding device is fixed, wherein the apparatus further comprises a stirrer for mixing liquid material, which is also arranged movable in the main direction of movement. As will be explained below, the device according to the invention can also be used for cooling a fusible material in a container.

The device can also be made movable in two or all three spatial directions. The main direction of movement is understood to mean the direction in which the heating element and the stirrer can be guided into and out of the container. In a preferred embodiment, the holding device is designed such that the heating element and the stirrer are movable in the vertical direction as a main movement direction through an opening in the top of the container.

The heating element according to the invention is tubular and can be flowed through by a fluid heat transfer medium. The tube cross section may have different shapes, preferably it is circular, oval or rectangular, in particular circular. The heating element is preferably made of a material having a high heat transfer coefficient. Particularly preferably, the heating element is made of stainless steel, aluminum or copper. The wall thickness is preferably from 1 to 2 mm, the inner diameter of 0.5 to 3 cm.

In a particularly advantageous embodiment, the heating element comprises a tube coil having a hollow cylindrical contour. This embodiment provides a large heat transfer area in a limited space. It is further preferred that the cylinder axis substantially corresponds to the main movement direction. This has the advantage that, given a given cross-section of the container opening, the outside diameter of the coiled tubing can be chosen as large as possible without jamming with the opening during extension and retraction of the heating element. A deviation of up to 10 ° between the hollow cylinder axis and the main direction of motion is still considered to be tolerable.

In order to ensure a liquid flow through the hollow cylinder not only in the axial, but also in the radial direction, a distance between the tube sections of the helix in the axial direction is preferably provided. The axial distance between adjacent pipe sections is preferably from 20% to 400%, more preferably from 50% to 200% of the outer diameter of the pipe.

In a preferred embodiment, the coiled tubing comprises two part coils with the same outer diameters of the hollow cylinders, wherein the part coiled into each other in the axial direction, are interconnected at their respective one end and open with their respective other end in the inlet opening or the drain opening. Also in this embodiment axially adjacent pipe sections are preferably spaced. In a further advantageous variant, the partial helix are arranged such that the axial distance between adjacent pipe sections is alternately 0% and from 50% to 400%, particularly preferably from 100% to 300% of the outer diameter of the pipe. That is, at one axial surface, the part coil touch, the other surfaces have an axial distance in the specified range. In a further preferred embodiment, the coiled tubing comprises two part coils with different outer diameters of the hollow cylinders, wherein the part coiled into each other in the radial direction, are interconnected at their respective one end and open with their respective other end in the inlet opening or the drain opening.

Both embodiments are also referred to below as a double helix. Preferably, the inlet opening and the outlet opening are located on the end face of the hollow cylinder, which faces away from the container during retraction and extension.

The heating element is preferably dimensioned such that the ratio of its length to its outer diameter of 1 to 10, more preferably from 1, 5 to 8, in particular from 2 to 6. The outer diameter of the heating element is preferably from 4 to 60 cm, more preferably from 8 to 20 cm, in particular from 10 to 16 cm. A length of 60 cm to 120 cm has proven to be advantageous for a number of applications.

In a preferred embodiment of the device according to the invention, the stirrer comprises a stirrer shaft, on which at least one stirring element is arranged, and whose axis corresponds essentially to the main direction of movement. In embodiments with a hollow-cylindrical heating element, the agitator shaft is preferably arranged in the interior of the hollow-cylindrical coiled tubing, particularly preferably coaxially with the cylinder axis.

The agitator shaft can be driven by known motors and transmissions, for example electrically or pneumatically. By selecting the stirring elements, the axial and vertical flow conditions in and around the heating element can be adjusted. Corresponding stirring elements, for example blade, disc, crossbar, impeller, anchor or propeller stirrers, are known to the person skilled in the art. The stirring elements are preferably made of stainless steel, depending on the application, enamelled or e.g. Teflon-coated stirring elements proven to counteract product adhesion. Preferably, the stirring elements are adjustable and / or replaceable attached to the agitator shaft.

In a preferred embodiment, the stirrer is arranged such that it is movable together with the heating element in the main movement direction. In this case, for example, components in which the stirrer is mounted, be firmly connected to the heating element or the holding device.

In a further preferred embodiment, the heating element and stirrer are arranged to be movable independently of one another in the main direction of movement. In this case, components in which the stirrer is mounted can be connected to the heating element in such a way that the stirrer can be moved in the main movement direction relative to the heating element. Preferably, however, the stirrer is movably mounted on the holding device in the main movement direction. Particularly Preferred is an arrangement of heating element and stirrer in which the stirrer move further into the container than the heating element. This allows, for example, the use of a stirring element which spreads depending on the speed and in the spread state has a larger diameter than the outer diameter of the heating element.

The device according to the invention may be provided with one or more sensors, for example for detecting the temperature, the viscosity or the conductivity of the liquefied material or the torque of the agitator shaft. From a change in the speed of the stirrer or its torque during operation can be concluded that changes in the melt properties such as the viscosity.

Another object of the invention is a method for melting a fusible material in a container having on its top an opening, by means of the device according to the invention, comprising the following steps:

Placing the lower end of the heating element on the surface of the material to be melted through the opening in the container,

Flow through the heating element with the heat transfer medium,

Sinking of the heating element into the material with progressive liquefaction of the material,

- mixing already melted material by rotation of the stirrer.

The flow through the heating element with the heat transfer medium need not necessarily be performed as a second step, it can also be started before the heating element is placed on the surface of the material to be melted. The flow can take place permanently during the melting process or intermittently. The steps of decreasing the heating element and the mixing due to the rotation of the stirrer may be performed sequentially or in parallel with each other. They can also be performed alternately one after the other. The heat transfer medium is selected depending on the melting range of the material to be melted. For a wide range of applications, hot to hot water with flow temperatures of 60 to 98 ° C is suitable. If the melting range of the material to be melted requires a higher flow temperature, superheated water or water-steam mixtures are suitable up to a temperature of approx. 160 ° C and a pressure of 4 bar. For even higher temperatures, a pure steam heating is recommended, in which case the components of the heating element must be pressure-resistant. Of course, depending on availability and application, other heat transfer media may be used, for example, oils such as marlotherm oil. These should be used in particular if water is not installed for safety reasons, eg if the contents of the container were to react violently with water in the event of a leak. Another object of the invention is a method for cooling a molten material in a container having on its top an opening, by means of the device according to the invention, comprising the following steps:

Introducing the heating element into the molten material through the opening in the container, flowing through the heating element with a cold heat transfer medium,

after solidification of the material, a brief increase in the temperature of the heat transfer medium for free melting of the heating element,

- Pulling out of the heating element from the free melted area. The flow through the heating element with the cold heat transfer medium need not necessarily be carried out as a second step, it can also be started before the heating element is introduced into the molten material. The flow can take place permanently during the melting process or intermittently. The cold heat transfer medium is selected depending on the melting point of the material to be cooled. For example, cold water, cooling water, brine or another substance are suitable if water is out of the question for the safety reasons already mentioned above. By immersing the heating element in the molten material, it can be cooled quickly and efficiently and optionally solidified depending on its melting point. In the case of a solidified material, the heating element can be briefly flowed through with a hot or hot heat transfer medium, so that the material liquefies in its immediate vicinity. Subsequently, the free-melted heating element is removed from the container and allowed to drain if necessary. The method for cooling a molten material is advantageously used when a final product is to be rapidly cooled or solidified, for example, to make it ready for rapid transport or to prevent crystallization of the material. Furthermore, it can also be used for the rapid cooling of liquids from the food industry, which may be warm or heated for a short time for the purpose of sterilization, for example wine, milk or fruit juices.

In an advantageous embodiment of the method according to the invention, the flow temperature to the heating element is set to a predetermined temperature. Corresponding thermostats or devices for temperature control are known to the person skilled in the art.

To protect against unwanted reactions in the container, for example, oxidations with atmospheric oxygen, a protective gas can be passed into the container during the implementation of the method. Preferably, this is nitrogen. The inventive method is particularly suitable for melting and / or cooling of

solid hydrocarbons or derivatives thereof, for example waxes and paraffins,

Polyether glycols derived from polyethylene, polypropylene or polybutylene glycols or mixtures thereof, which may optionally also be alkylated,

Fats or solid fat-water emulsions,

solid salts, ionic liquids, metals or alloys,

solid mono-, di- or polyisocyanates, low molecular weight prepolymers or silicones,

solid sulfur or organic anhydrides such as maleic anhydride or phthalic anhydride.

The inventive methods are suitable for various transport containers, especially for barrels, transport containers, railway cars, road containers and road tankers. Depending on the application, several devices according to the invention can also be used.

The invention enables the gentle melting and tempering of the contents of a transport container by the direct contact of a tempered heating element with the material to be melted in the container. By generating a flow in the melt by stirring during the heat input into the melt, the container contents are additionally mixed homogeneously, and the duration of the melting process is reduced considerably in comparison with known methods. This also significantly minimizes potentially harmful side effects of the melting process, such as thermal damage to the material or undesired reactions in the container. The device according to the invention is simple in construction and can be used flexibly.

With reference to the drawings, the invention will be further explained in the following, the drawings being to be understood as schematic representations. They do not constitute a limitation of the invention, for example with regard to specific dimensions or design variants of components. For better representability, they are generally not to scale, in particular with regard to length and width ratios. Show it:

Fig. 1: embodiment of a device according to the invention with double helix as a heating element

2: detail of FIG. 1

Fig. 3: Example of the use of a device according to the invention for continuous

Melting of solid flakes

Fig. 4: embodiment of a device according to the invention for use in barrels List of reference numbers used

10. , heating element

1 1. , inlet opening

12. , drain hole

13. , supply line

14. , drain line

15. , coiled tubing

16. , reinforcing element

20. , holder

21. , guide rod

22. , guide sleeve

23. , end stop

30. , stirrer

31. , agitator shaft

32. , stirrer

33. , engine

40. , container

41. , insulated container wall

42. , wire mesh

43. , hopper

44. , Outlet for melt

45. , Solid flakes

46. , melt

47. , gas inlet

In Fig. 1, a preferred embodiment of a device according to the invention is shown. The heating element 10 is tubular in shape as a double helix 15, which has a hollow cylindrical contour. The two part coils have the same outer diameter of the hollow cylinder and run into one another in the axial direction. The axial distance between adjacent pipe sections is alternately 0% and 200% of the tube outer diameter, that is, on one axial surface, the part of the coil touch, the other surfaces have an axial distance corresponding to twice the tube outer diameter. At their respective one end, in Fig. 1 the lower end, the part coil are connected together. With their respective other end open the partial coil in the inlet opening 1 1 and in the drain opening 12. The inlet opening 1 1 and the drain opening 12 are located on the end face of the hollow cylinder, which faces away from the container during retraction and extension. For flow through a heat transfer medium, the two openings with a supply line 13 and a drain line 14 are connected. In order to reinforce the hollow cylinder structure against radial deflection, three band-shaped reinforcing elements 16 are provided in the illustrated example, which extend axially on the outside of the double helix and are firmly connected, eg welded or soldered, to at least some pipe sections. The holding device 20 comprises two guide rods 21, on which a guide sleeve 22 is slidably mounted. In order to prevent the guide sleeve 22 from sliding out of the guide rods 21, these are each provided with an end stop 23 at their lower ends. Preferably, the end stop 23 along the guide rods 21 is variably adjustable in order to limit the sinking depth of the heating element 10 in a container can. The guide sleeve 22 is connected to the inlet and the discharge pipe of the double helix 15.

The holding device 20 may be fixedly mounted, for example on a wall, a ceiling or a free-standing scaffolding, or it may be used on mobile, for example, placed with its lower end on a transport container. In an advantageous embodiment with a stationary holder, the holding device is firmly connected to a wall. The transport container to be treated is placed under the holding device. The heating element and the stirrer can be placed on the holding device in the main direction of movement vertically down through the opening in the top of the transport container on the material to be melted. Preferably, heating element and stirrer are moved via a manually or electrically operated cable pull.

In the interior of the hollow cylindrical double helix 15, a stirrer 30 is coaxially arranged. It comprises a stirrer shaft 31 and, in this example, three stirring elements 32 attached thereto. FIG. 2 shows the lower end of the device from FIG. 1 as a detailed detail. From this figure, the agitator shaft 31 and attached stirring elements 32 are more clearly visible. The bearing of the agitator shaft 31 is not shown in the figures. It can be carried out independently of the bearing of the heating element, in order to allow an axial relative movement between heating element 10 and agitator 30. The axial relative movement makes it possible to move the stirrer further into the container than the heating element. This allows, for example, the use of a stirring element which spreads depending on the speed and in the spread state has a larger diameter than the outer diameter of the heating element. In order to liquefy the contents of a transport container, for example an IBC, the device according to FIG. 1 is placed with its holding device 20 on the opening in the upper side of the container. The heating element 10 is placed on the solid content of the container and put into operation by flowing through it with a warm or hot heat transfer medium, for example, with hot water. The material in the immediate vicinity of the tubular coil 15 begins to melt, whereupon the heating element 10 is immersed in the melt due to its own weight or guided downwards. The stirrer 30 inside the heating element 10 is also immersed in the resulting melt. As soon as one or more of the stirring elements 32 are in the melt, the stirrer is switched on. As a result of the flow thus caused in the melt, the heat transfer between the heat transfer medium and the material to be melted is significantly improved. In addition, the melt is homogenized in this way. After some time, the container contents are completely melted and homogeneously mixed. The stirrer 30 is switched off, the heating element 20 removed from the container and allowed to drain. The transport container can now be removed a desired amount of liquid, homogeneously mixed material.

Experience has shown that only a small part of the energy introduced by the heat transfer medium is needed to melt the solid material. It is therefore also possible to connect several devices in series or in parallel and to operate them in an energy-efficient and cost-efficient manner. Advantageously, a scheme can be provided which optimizes the melting process by the energy input is then increased when there is enough melt to absorb the thermal energy. A preferred control strategy provides, for example, first to melt the material with little energy input until the heating elements have sunk to a predetermined length, and then to increase the temperature of the heat transfer medium and / or the flow of heat transfer medium.

In a preferred embodiment, three to five devices according to the invention are interconnected on the side of the heat transfer medium, the heat transfer medium is pumped in a circle and the energy required for introduction into the melt is continuously introduced into the circuit, e.g. by a heat exchanger or an inflow of heat transfer medium at a higher temperature than present in the circulation stream. For example, it is advantageously possible to use hot condensate from a process plant.

In addition to the discontinuous use for liquefying solid container contents, the device according to the invention can also be used continuously. 3 shows an example of the use of a device according to the invention in a continuous process for melting solid flakes. Shown is a schematic diagram of a longitudinal section through a container 40, which comprises an upper cylindrical part and a downwardly adjoining conical part. The container wall 41 is preferably made thermally insulated. In the lid of the container is a hopper 43 for solid flakes 45, which is equipped with a flap for dosing the flakes. At the lower end of the conical part there is an outlet 44 for the melt 46. At the transition from the cylindrical see to the conical part, a wire screen 42 is mounted, the mesh size is such that only the melt can flow into the conical part, and optionally still in the melt located flakes are retained.

In a further opening in the lid, the holding device 20 of a device according to the invention is attached. Their construction corresponds essentially to that shown in FIG. Only the holding device 20 is modified. The inlet pipe and the drain pipe are attached to a respective guide rod. The two guide rods are slidably mounted in two sleeves, which are connected via the holding device 20 fixed to the container lid. The length and position of the elements of the holding device are selected such that the lower end of the device is in the completely sunken state just above the wire screen 42. The process for the continuous melting of solid flakes can be carried out, for example, as follows: First, portions of flakes 45 are filled into the container interior until they have reached a height starting from the wire screen 42 so that they come into contact with the heating element 10. The heating element 10 is put into operation and flows through with hot water as the heat transfer medium. The melt 46 collects in the lower, conical part of the container, while continuously refilled through the hopper 43 flakes. As soon as approximately half of the container is filled with melt, a continuous melt discharge through the outlet 44 is started. During the flake supply, nitrogen is added via a gas inlet 47 as protective gas.

This melting process can be advantageously used to continuously supply a downstream plant with a molten feedstock, e.g. one of the above substances. For a polyethylene glycol (PEG 6000, melting range about 45 ° C to 60 ° C), for example, a heating element with a ratio of length to outer diameter of 1, 5 is suitable when it is operated with hot water of about 80 ° C. Nitrogen is supplied to the vessel at a rate of 80 liters per minute to protect it from oxidation.

Examples

In the examples 1 to 4 described below, an embodiment of the device according to the invention was used, which corresponded in principle to that shown in Fig. 1. The heating element was made of a stainless steel tube with a wall thickness of 1, 5 mm and an inner diameter of 9 mm. The heating element comprised a double helix with an outer diameter of the hollow cylinder of 13.5 cm and a length of the double helix of 72 cm. The axial distance between adjacent pipe sections was 200% of the pipe outside diameter. The stirrer was pneumatically driven and was speed controlled. On the agitator shaft, three propeller stirrers were arranged as stirring elements at a distance of 20 cm each. The outer diameter of the propeller stirrer was about 8 cm.

Example 1 An IBC was filled with 750 kg of n-octadecane (melting point 28 ° C). The mass was present as a homogeneous solid block in the container. The IBC was opened at the top and the lower end of the holding device of the device according to the invention was placed on the edge of the opening. The heating element was movable in the vertical direction and was placed with its lower end on the solid mass. To heat the solid, the heating element was flowed through with hot water as the heat transfer medium. The water was passed gravimetrically from a condensate tank with a flow temperature of about 80 ° C and a flow rate of about 5 l / min in the heating element. The exiting from the outlet of the heating element Water was discarded. After about 60 minutes, the heating element had melted into the solid over the entire length of the coiled tubing, whereupon the stirrer was switched on at a speed of about 200 rpm. After a total of 12 hours, the entire contents of the container was melted and homogeneously mixed.

The heater was pulled out of the IBC and allowed to drain. After two minutes it was sufficiently clean to be put on the next container. In the meantime, a heated feed pump and a trace-heated pipe were connected to the bottom cock of the IBC and the container was pumped out for further use of the material.

Comparative Example 1

An IBC comparable to Example 1 was placed in a heating cabinet (Fa. Conthermo, 50 m ² heating surface, 4 bar steam-heated) with a tempered volume volume of 2.3 m ³ and a set room temperature of 70 ° C and the lid of the IBC for pressure equalization sufficiently relaxed. The reflow process was visually checked for progress every two hours. Only after 63 hours in the oven, a complete melting of the contents was found. The container was removed from the oven and its contents further processed.

Example 2 The experimental set-up was the same as in Example 1, except that the IBC was filled with 750 kg of the wax mixture LINPAR® 18-20 (supplied by Sasol). The wax mixture consists mainly of n-alkanes of chain length C17 to C19 and has a melting point of about 30 ° C). After about 15 minutes, the coiled tubing was melted over its entire length in the wax mixture, whereupon the stirrer was turned on. After a total of six and a half hours, the entire contents of the container were melted and a subset of 145 kg was removed.

Comparative Example 2 Under the same conditions as in Comparative Example 1, a wax compound LINPAR® 18-20 in an IBC was placed in a heating cabinet. After 33 hours, the mixture was completely melted and the IBC was removed from the oven. With an attached stirrer, the contents of the IBC were homogenized for a period of 10 minutes before a subset of 145 kg of the wax mixture could be removed. Example 3

The experimental setup corresponded to that in Example 1 with the difference that the IBC was filled with 750 kg of a mixture of saturated n-paraffinic hydrocarbons (melting range about 27 ° C to 31 ° C). After about 30 minutes, the coiled tubing was melted into the mixture over its entire length, whereupon the stirrer was switched on. The entire reflow process of the complete IBC content took 8 hours. After melting, a partial amount could be taken from the IBC. Comparative Example 3a

Under the same conditions as in Comparative Example 1, a mixture according to Example 3 in an IBC was placed in a heating cabinet. After 37 hours, the mixture was completely melted and the IBC was removed from the oven. With an attached stirrer, the contents of the IBC were homogenized for 30 minutes before a subset of the mixture could be withdrawn.

Comparative Example 3b An IBC according to Example 3 was wrapped with a commercially available, electrically operated heating tape and heated. After one week of heating, the contents had still not melted and the attempt was stopped.

Example 4

A clamping ring drum with a capacity of 200 liters was filled with 210 kg of a solid emulsifier (melting point about 26 ° C). The main constituent of the emulsifier was p-octylphenol ethoxylate with about 25 moles of EO. The mass was present as a homogeneous solid block in the barrel. The drum cover was removed, and placed the lower end of the holding device of the device according to the invention on the edge of the opening. All further process steps corresponded to those described in Example 1, wherein water was used with a flow temperature of 67 ° C as the heat transfer medium. The stirrer was switched on about one hour after the beginning of the melting process. After 14 hours, all of the contents of the keg had melted and the melt could be pumped to dilute it into a reaction vessel containing hot water.

Comparative Example 4a Under the same conditions as in Comparative Example 1, a barrel with emulsifier according to Example 4 was placed in a heating cabinet. After 67 hours, the drum contents were completely melted. Comparative Example 4b

In a basin with the dimensions 4 x 3 x 2 meters (length x width x depth), which was filled with 15 m ^{3 of} water, four pallets were introduced closed with four barrels according to Example 4 and completely submerged. A constant stream of steam was introduced into the basin for two days, heating up the water and continuously heating the contents of the drum. Experience has shown that after two days of storage the drum contents are completely melted. This usual procedure is complex and very energy intensive. In addition, sampling or control of the reflow process is only possible if a complete pallet is recovered. It has also proven to be disadvantageous that the barrels begin to rust very soon as a result of this treatment.

Example 5

In the two examples described below, an embodiment of the device according to the invention was used, which corresponded in principle to that shown in Fig. 4. The heating element 10 was made of a stainless steel tube with a wall thickness of 1, 5 mm and an inner diameter of 9 mm. The heating element comprised a simple tube coil 15 with an outer diameter of the hollow cylinder of 40 cm and a length of the coiled tubing of 60 cm. The axial distance between adjacent pipe sections was 100% of the pipe outside diameter. The upper end of the tube coil 15 led into the inlet opening 1 1. The lower end of the tube coil 15 was guided as a straight piece of pipe on the inside of the hollow cylinder upwards and led into the discharge opening 12. To reinforce the hollow cylinder structure against radial bending were four band-shaped reinforcing elements 16 provided, which extend axially on the outside of the coiled tubing and were firmly connected at least with some pipe sections. The heating element was designed with a view to melting material in barrels. The diameter of the hollow cylinder has been chosen such that viewed in cross-section perpendicular to the hollow cylinder axis of the area of the circle within the hollow cylinder substantially corresponds to the surface area of the annulus between the hollow cylinder and barrel inner wall. The test results set out below were obtained with the heating element without the use of a stirrer. In comparison to conventional methods for melting the material in the barrels, significantly shorter times could already be achieved with the heating element alone. When using a stirrer, due to the better mixing, once again reduced periods of time for the melting process are to be expected. Example 5a

The inventive device was placed in an empty Spannringfass with 200 liter capacity and the heating element as described in Example 1 put into operation. Under suction, 100 kg of maleic anhydride flakes (melting point 53 ° C) were filled into the barrel and melted. The melting process for the total amount of 100 kg took one hour.

Example 5b

The inventive device was placed in an empty Spannringfass with 200 liter capacity and 100 kg of polyethylene glycol 6000 (melting range about 45 ° C to 60 ° C) filled as a flake. Subsequently, the heating element with hot water as a heat transfer medium with a temperature of about 90 ° C was put into operation. After six hours, the entire contents of the drum had melted, so that the melt could be pumped into a storage tank. For the next melting process again 100 kg of flakes (four sacks of 25 kg) were filled into the clamping ring barrel.

Comparative Example 5b

The dandruff barrel filled with flakes was placed in a heat chamber whose interior temperature was set to 90 ° C. The drum contents were completely melted after 19 hours and could be removed for further use.

Most of the experiments described above were done in the winter. The temperature of the material to be melted before the start of the reflow process was not determined. However, it was the same in the examples and related comparative examples, since the transport containers and barrels were stored in the same place outdoors or in unheated halls.

Examples 6 and 7 illustrate the possible uses of the device according to the invention for the cooling of fusible material. They have not yet been confirmed experimentally. Example 6

In a reaction vessel with a reaction volume of 10 m ³ , a catalyzed solvent-free reaction of a mixture of two different bifunctional isocyanates with a mixture of two diols and a triol to a viscous polyurethane melt is carried out at 110 ° C. The lot size is around six tons. The reaction product must be filled after the completion of the reaction in seven provided IBCs, the cooling process should be carried out quickly and controlled as the reaction product still reacted at the present temperature with increase in viscosity. For filling, the IBCs are next to each other and each IBC is equipped with a device according to the invention as described above, which are each introduced into the empty IBCs. The devices are connected in series to a common cooling circuit and serve to cool the reaction product. Each stirrer is equipped with stirrer speed monitoring. The interconnection of the heating elements is carried out according to the counterflow principle contrary to the order of filling the IBCs. This has the consequence that the IBC currently being filled in each case comes into contact with the coldest coolant flow. As the temperature of the reaction product in the reaction vessel decreases, the viscosity of the mixture increases sharply. Therefore, it is not appropriate to completely cool the reaction product in the reaction vessel. After complete reaction, the mixture is cooled only to about 75 ° C internal temperature and filled under pressure with nitrogen from the reaction vessel via heated lines in the IBCs on the bottom tap. After completing the filling of an IBC, the lines are blown out by means of a nitrogen pressure surge and the corresponding bottom tap is closed.

In the devices, the agitator shaft is lowered about 10 cm from the lower end of the coiled tubing and immersed in the product before this. As the melt surface rises and contact with the coiled tubing, slow cooling sets in, but this does not work until the container is completely filled and no other hot product is flowing. The lowering of the product temperature takes place with a simultaneous increase in intrinsic viscosity until the increasing viscosity leads to a decrease in the stirrer speed. If the speed falls below a predetermined, product-dependent value, the respective device is pulled out of the melt of the IBC. After about 3 hours of cooling, the temperature inside the IBCs has dropped to about 45 ° C. When all IBCs are filled and the devices are pulled out of the IBCs, the cooling is turned off and hot water is passed through the coiled tubing to liquefy adhering product remnants and drain into the IBCs. Thereafter, the IBCs are closed for transport.

Example 7

To produce a defined wax mixture of 2 parts of n-octadecane, 1 part of n-eicosane (C20H42, melting range 36-39 ° C) and 1 part of n-docosan (C22H46, melting range 41-44 ° C), four separate IBCs with the raw materials melted analogously to Example 1 and successively pumped into a dry, nitrogen-filled and preheated to 60 ° C stirred reaction vessel and homogenized for 30 minutes. The devices according to the invention are switched to cooling and flowed through with tempered at + 10 ° C brine. The liquid wax mixture is pushed back from the stirred tank into the IBCs, filling the IBCs. Upon contact of the liquid wax melt with the cool coiled tubing, the mass solidifies quickly and grows around the coiled tubing to the outside. The Cooling is maintained until the entire contents of the IBCs are fully solidified and present as a block, which is the case after about 6 hours. The temperature of the heat transfer medium is then increased to 43 ° C for a period of three minutes to liquefy the environment of the coiled tubing and withdraw the devices from the IBCs. Compared to the usual method in which the container contents are not actively cooled, but slowly solidifies, a more homogeneous distribution of the container contents is achieved by the inventive method. As proof, drilling samples may be taken at different locations in the IBC, which are analyzed for physical properties such as melting temperature.

Claims

claims

Device for heating or cooling a fusible material in a container comprising a heating element (10) and a holding device (20), wherein the heating element (10) tubular with an inlet opening (1 1) and a drain opening (12) designed to flow through with a heat transfer medium and in at least one spatial direction as the main movement direction movably attached to the holding device (20), characterized in that the device further comprises a stirrer (30) for mixing liquid material, which is also arranged movably in the main movement direction.

Apparatus according to claim 1, wherein the holding means (20) is designed such that the heating element (10) and the stirrer (30) are movable in the vertical direction as a main movement direction through an opening in the top of the container.

Apparatus according to claim 1 or 2, wherein the heating element (10) comprises a coiled tubing (15) having a hollow cylindrical contour, and the cylinder axis substantially corresponds to the main movement direction.

Apparatus according to claim 3, wherein the axial distance between adjacent pipe sections is from 20% to 400%, preferably from 50% to 200% of the outer diameter of the pipe.

Apparatus according to claim 3, wherein the coiled tubing (15) comprises two part coil with the same outer diameter of the hollow cylinder, which extend in the axial direction into each other, are interconnected at their respective one end and with their respective other end in the inlet opening (1 1) or Drain opening (12) open.

Apparatus according to claim 3, wherein the coiled tubing (15) comprises two part coils with different outer diameter of the hollow cylinder, which extend in the radial direction into each other, are interconnected at their respective one end and with their respective other end in the inlet opening (1 1) or Drain opening (12) open.

Device according to one of claims 3 to 6, wherein the heating element (10) is dimensioned such that the ratio of its length to its outer diameter of 1 to 10, preferably from 1, 5 to 8, in particular from 2 to 6, and the outer diameter of the heating element (10) of 4 cm to 60 cm, preferably from 8 cm to 20 cm, in particular from 10 cm to 16 cm.

Device according to one of claims 1 to 7, wherein the stirrer (30) comprises a stirrer shaft (31) on which at least one stirring element (32) is arranged, and whose axis

4 Fig. essentially corresponds to the main movement direction.

9. Apparatus according to claim 8, wherein the agitator shaft (31) in the interior of the hollow cylindrical tube coil (15) is arranged.

10. Device according to one of claims 1 to 9, wherein the heating element (10) and the stirrer (30) are mounted independently of each other in the main movement direction movable on the holding device (20). 1 1. Method for melting a fusible material in a container having an opening on its upper side, by means of a device according to one of claims 1 to 10, characterized by the steps:

Placing the lower end of the heating element (10) on the surface of the material to be melted through the opening in the container,

Flowing through the heating element (10) with the heat transfer medium,

Lowering of the heating element (10) into the material as the liquefaction of the material proceeds,

Mixing already molten material by rotation of the stirrer (30). A method of cooling a molten material in a container having an opening on its upper side by means of a device according to any one of claims 1 to 10, characterized by the steps of:

Inserting the heating element (10) into the molten material through the opening in the

Container,

Flowing through the heating element (10) with a cold heat transfer medium,

after solidification of the material short-term increase in the temperature of the heat transfer medium for free melting of the heating element (10),

Pulling out the heating element (10) from the free melted area. 13. The method of claim 11 or 12, wherein the container is a drum, a transport container, a railroad car, a road container or a road tanker train.

4 Fig.