DE102022104505A1 - Process and separation device for separating water from a carbohydrate-water mixture - Google Patents

Abstract

The invention relates to a method for separating water from a carbohydrate-water mixture (4), wherein the carbohydrate-water mixture (4) is introduced into at least one separation unit (3) in which water is separated from the carbohydrate-water Mixture (4) is separated, wherein- useful heat is supplied to the at least one separation unit (3) on a high-temperature side (9) in order to thermally separate the water from the carbohydrate-water mixture (4), wherein- the at least one separation unit ( 3) thermal secondary energy is dissipated on a low-temperature side (13), wherein- recycling heat is removed from the thermal secondary energy on the low-temperature side (13), and wherein- the recycling heat is transferred to the high-temperature side (9 ) is fed back in at a temperature level of more than 100 °C, at least as part of the useful heat.

Description

The invention relates to a method and a separating device for separating water from a carbohydrate-water mixture.

In order to separate water from a water-containing mixture, such a mixture is introduced into at least one separation unit, useful heat being fed to the separation unit on a high-temperature side, by means of which the water is thermally separated. The at least one separation unit also has a low-temperature side on which secondary thermal energy is dissipated. In order to make the process efficient, recycling heat can be taken from the thermal secondary energy, which is fed back on the high-temperature side at least as part of the useful heat. In order to increase the temperature level of the recycle heat, a heat pump can be provided. If an adsorption heat pump or an absorption heat pump is used, this leads to a limitation of the available temperature range and/or entails problems with regard to the efficiency and controllability of the process. If a vaporous medium exiting on the low-temperature side of a separation unit is compressed and fed back directly to a high-temperature side of the same or another separation unit, for example in the form of what is known as vapor compression, this disadvantageously leads to a mixing of different material flows, in particular a mixing of different condensate qualities or even possibly a mixing of one heating medium with the product. In addition, with this configuration there is the risk of drops entering a compressor impeller provided for the compression of the medium, which represents a not inconsiderable operating risk for the compressor. If the recycling heat is to be returned via a plurality of discrete separation stages, this design also requires a multi-stage arrangement of compressors connected in series, which means that the risk of failure of the entire separation device is high, since the recycling heat can no longer be guaranteed even if a single compressor in the multi-stage arrangement fails is. Furthermore, the size of the compressors depends on the specific volume of the medium to be compressed, which leads to design problems, especially in the low-pressure range.

The invention is therefore based on the object of creating a method and a separating device for separating water from a carbohydrate-water mixture, the disadvantages mentioned not occurring.

The object is achieved by providing the present technical teaching, in particular the teaching of the independent claims and the embodiments disclosed in the dependent claims and the description.

The object is achieved in particular by creating a method for separating water from a carbohydrate-water mixture, the carbohydrate-water mixture being introduced into at least one separation unit in which water is separated from the carbohydrate-water mixture, wherein useful heat is supplied to the at least one separation unit on a high-temperature side in order to thermally separate the water from the carbohydrate-water mixture, secondary thermal energy being removed from the at least one separation unit on a low-temperature side, recycling heat being removed from the secondary thermal energy on the low-temperature side, and wherein the recycling heat is fed back to the high-temperature side at a temperature level of greater than 100° C. at least as part of the useful heat by means of a compression heat pump having a closed working medium circuit. By using a compression heat pump, which has a closed working medium circuit, the recycling heat is advantageously returned from the low-temperature side to the high-temperature side, without a material flow being returned at the same time; Rather, the high-temperature side is connected to the low-temperature side purely thermally, ie thermally, by a flow of heat, but remains materially separate from the low-temperature side with regard to the recirculation of the recycling heat. This advantageously avoids mixing of different material flows, in particular mixing of different condensate qualities or even a heating medium with the product. The risk of droplets entering a compressor impeller is completely eliminated, and the recirculated heat flow can be influenced in a simple manner via the amount of working medium circulated in the compression heat pump, with a number of compressors not being connected in series, particularly in the case of multi-stage recirculation of the recycling heat. The operational risk of a disconnection device operated with the method proposed here is therefore low. Advantageously, the use of a compression heat pump with a closed working medium circuit also allows a comparatively high temperature level of more than 100° C. on the high-temperature side. In particular, at a temperature of more than 100° C., such a compression heat pump also has a high level of efficiency, in particular in comparison to an adsorption or absorption heat pump. Except such a compression heat pump has very good controllability by varying the compressor speed, especially in partial load operation.

In the context of the present technical teaching, a compression heat pump having a closed working medium circuit is understood to mean, in particular, a thermotechnical device that executes a thermotechnical cycle process that is also referred to as counterclockwise. In particular, the compression heat pump - in particular in the specified order along a flow direction of the working medium in the closed working medium circuit - has an expansion valve or a throttle for expanding the working medium, a first working medium heat exchanger, in particular a working medium evaporator, at least one working medium compressor or compressor, and a second working medium heat exchanger, in particular a working medium condenser. The compression heat pump is in particular a high-temperature heat pump or a maximum-temperature heat pump. The working medium circuit has in particular a refrigerant as the working medium, in particular a hydrofluoroolefin or a hydrochlorofluoroolefin, in particular (Z)-1,3,3,3-tetrafluoropropene, (E)-1,3,3,3-tetrafluoropropene, 1,1, 2,2,3-pentafluoropropane, (Z)-1-chloro-3,3,3-trifluoropropene, (E)-1-chloro-3,3,3-trifluoropropene, (Z)-1-chloro-2-, 3,3,3-Tetrafluoropropene, (E)-1-chloro-2,3,3,3-tetrafluoropropene, (Z)-1,1,1,4,4,4-hexafluoro-2-butene, 1, 1,1,3,3-pentafluorobutane, dodecafluoro-2-methylpentan-3-one, isobutane, butane, or n-pentane. The working medium compressor or compressor is in particular a mechanical compressor or compressor, in particular a reciprocating compressor, screw compressor or turbo compressor. The amount of working media circulated in the working media circuit per unit of time and thus the recirculated heat flow can be adjusted in particular by suitably controlling the working media compressor or compressor, in particular by varying the speed of the working media compressor or compressor.

In the context of the present technical teaching, the fact that the recycling heat is fed back to the high-temperature side at a temperature level greater than 100° C. means in particular that the condensation temperature of the working medium is greater than 100° C. during operation of the compression heat pump.

In particular, the useful heat of the high-temperature side is supplied as thermal primary energy.

In one embodiment of the method, it is provided that the useful heat is supplied to the high-temperature side—in particular directly—by means of a heating medium, in particular by means of heating steam. In particular, the separation unit has at least one heating surface, preferably a plurality of heating surfaces, which is acted upon by the heating medium on one side of the heating medium and is in thermal contact, in particular in physical contact, with the carbohydrate-water mixture on a product side facing away from the heating medium side.

In one embodiment of the method, it is alternatively or additionally provided that the useful heat is supplied to the high-temperature side by overheating the carbohydrate-water mixture. In particular, the separating unit in this case has an evaporation space in which water can be evaporated—particularly abruptly or suddenly—from the superheated carbohydrate/water mixture, particularly in the form of a formation of flash steam. The carbohydrate/water mixture is in particular superheated upstream of the evaporation space, ie before the carbohydrate/water mixture enters the evaporation space. In particular, there is a pressure in the evaporation space that is lower than the pressure that prevails upstream of the evaporation space at the point at which the carbohydrate-water mixture is overheated.

The term "upstream of a first element" means here and in the following in general that a so-called second element is arranged along a flow or flow direction in front of the first element, i.e. of a test element moving - possibly imaginary - along the flow or flow direction first - before the first element - is reached. Correspondingly, the term “downstream of a first element” means that a so-called second element is arranged along a direction of flow behind the first element, ie is reached by the test element later—after the first element.

In the context of the present technical teaching, a separation unit is understood to mean in particular a device—also referred to as an evaporation stage—that is set up in such a way that the device, in particular in the device, can be used to separate water from a carbohydrate-water mixture.

According to one embodiment, the separation unit has at least one heating surface, preferably a plurality of heating surfaces, wherein the at least one heating surface is designed to to be acted upon by the heating medium on a heating medium side of the at least one heating surface, and to be brought into thermal contact, in particular touching contact, with the carbohydrate-water mixture on a product side of the at least one heating surface facing away from the heating medium side. Such a separation unit can be designed in particular as a falling film evaporator.

Alternatively or additionally, according to one embodiment, the separation unit has an evaporation chamber, which is arranged and set up in such a way that in the evaporation chamber - in particular abrupt or sudden - evaporation of water from the superheated carbohydrate-water mixture, in particular in the form of flash -Steam, can be done. In one embodiment of the separation unit, an overheating device is provided upstream of the evaporation space, which is set up to overheat the carbohydrate-water mixture before it enters the evaporation space.

In the context of the present technical teaching, a separating device has in particular at least one such separating unit, in particular a plurality of such separating units. In terms of flow, the separation units are arranged one behind the other with respect to a heat flow on the one hand and a product flow of the carbohydrate-water mixture on the other hand, ie in particular arranged in series or connected in series. In one embodiment, it is provided that the sequence of the separation units with regard to the heat flow on the one hand and with regard to the product flow on the other hand corresponds. In another embodiment, however, it is also possible for the sequence of the separation units with regard to the heat flow to differ from the sequence of the separation units with regard to the product flow. In particular, it is possible for the order in terms of the product flow to be in the opposite direction to the order in terms of the heat flow. However, according to yet another embodiment, it is also possible that there is at least no simple correlation between the order in terms of the heat flow on the one hand and the order in terms of the product flow on the other hand.

In one embodiment, the separating device has only separating units, each with at least one heating surface. In another embodiment, the separating device has only separating units, each with an evaporation space. In yet another embodiment, the separating device has at least one separating unit with at least one heating surface and at least one further separating unit with an evaporation chamber.

In the context of the present technical teaching, separating water from a carbohydrate-water mixture is understood in particular to mean that water is removed or expelled from the carbohydrate-water mixture, with a water content of the carbohydrate-water mixture being reduced and a carbohydrate Proportion of the carbohydrate-water mixture is increased. In particular, a product stream of the carbohydrate-water mixture is divided into a first part-product stream, which has a concentrated carbohydrate-water mixture with an increased carbohydrate content, and a second part-product stream, which only contains water or a diluted carbohydrate-water Mixture with increased water content.

In the context of the present technical teaching, thermal separation is understood to mean, in particular, separation by supplying heat, with the water being removed from the carbohydrate-water mixture due to the heat supplied. In particular, in one embodiment, the water is separated from the carbohydrate-water mixture by the water being expelled—in particular by evaporation, in the form of water vapor. The resulting partial product stream, which consists at least essentially of water - possibly with entrained portions of carbohydrate - is also referred to as vapor. Also in a broader sense, a steam generated in particular from a condensate, or also a steam containing alcohol, is sometimes referred to as vapor in the following. In ethanol production in particular, the essential component of the vapor is an alcohol.

In the context of the present technical teaching, useful heat is understood to mean heat or, synonymously, thermal energy, which is supplied to the at least one separation unit—in particular as thermal primary energy—in order to thermally separate the water from the carbohydrate-water mixture.

In the context of the present technical teaching, thermal secondary energy is understood to mean in particular heat or, synonymously, thermal energy, which is discharged from the at least one separation unit on the low-temperature side. In particular, the secondary thermal energy embodied in the separated water is removed, in particular in the form of steam, in particular in the form of vapor. However, thermal secondary energy can also be removed in the form of a condensate, in particular the recycling heat also being a condensate Separation unit can be removed. It is possible that the recycling heat is taken directly from the condensate. However, it is also possible for the condensate to first be fed to another heat sink and for the recycling heat then to be taken from the remaining residual heat of the condensate.

In the context of the present technical teaching, recycling heat is understood to mean in particular that proportion of the thermal secondary energy which is removed on the low-temperature side and returned to the high-temperature side by means of the compression heat pump. In particular, additional heat is generated by the compression heat pump, which is referred to as heat pump heat, with the recycling heat being fed back to the high-temperature side at least as part of the useful heat, increased by the heat pump heat.

According to a development of the invention, it is provided that the carbohydrate-water mixture is selected from a group consisting of: a sucrose-containing medium, in particular a sucrose-containing solution or a sucrose-containing suspension, in particular thin juice or thick juice for the production of sucrose, sucrose syrup, an isomaltulose-containing medium, in particular an isomaltulose-containing solution or an isomaltulose-containing suspension, stillage from bio-alcohol production, an alcohol-water solution, in particular an bio-alcohol-water solution, a sugar-alcohol-water medium , in particular a sugar alcohol-water solution or a sugar alcohol-water suspension, a starch-containing medium, in particular a starch-containing solution or a starch-containing suspension, and moisture-containing crop pieces, in particular sugar beet pulp or chicory roots.

In the following, a thin juice is generally understood to mean a carbohydrate-water mixture with a lower dry matter content and a thick juice means a corresponding carbohydrate-water mixture with a higher dry matter content. The dry matter content of the thick juice is higher than the dry matter content of the thin juice, and vice versa. In particular, i.e. where this is expressly stated or results from the context, a thin juice is understood to mean a sucrose solution with a lower dry matter content and a thick juice means a sucrose solution with a higher dry matter content.

In particular, as part of the process, a thin juice, in particular with a dry matter content of 10% to 25%, is preferably concentrated to form a thick juice with a dry matter content of 65% to 80%. As an alternative or in addition, a desired supersaturation is set or achieved in a crystallization process as part of the method by separating off water. Alternatively or additionally, a rectification process is carried out as part of the process by separating off water. Alternatively or additionally, as part of the process, sugar beet pulp and/or products from bioethanol production are dried in a dry matter range of 30% to 95%.

According to a development of the invention, it is provided that a plurality of separation units is used to separate the water from the carbohydrate-water mixture. The separation units are thermally connected to each other and arranged in series along a heat flow, wherein the recycle heat of the secondary thermal energy on the low-temperature side of a downstream separation unit of the plurality of separation units is extracted and fed to the high-temperature side of an upstream separation unit of the plurality of separation units by means of the compression heat pump. The upstream separation unit is located upstream of the downstream separation unit along the heat flow. Correspondingly, the downstream separation unit is arranged downstream of the upstream separation unit along the heat flow.

In particular, the separation units are arranged one behind the other in series along a temperature gradient and are thermally connected to one another. The term “upstream of a first element” means that a so-called second element is arranged along the temperature gradient at a higher temperature level than the first element. Correspondingly, the term "downstream of a first element" means that a second element so designated is arranged along the temperature gradient at a lower temperature level than the first element.

In particular, the low-temperature side of a separating unit is in each case thermally connected—apart from the last separating unit in the row—to the high-temperature side of a separating unit immediately following along the heat flow. Correspondingly, the high-temperature side of a separation unit is in each case thermally connected—apart from the first separation unit in the row—to the low-temperature side of a separation unit that immediately precedes it along the heat flow. In one configuration, at least one separation unit has at least two partial separation units which are arranged parallel to one another with regard to the heat flow, that is to say in particular at the same temperature level. The at least two partial separation units are preferably arranged in series or in series, ie one behind the other, with respect to the product stream.

In particular, the separation units are additionally arranged one behind the other in a row along a pressure gradient. In particular, the pressure gradient has the same sign as the temperature gradient. In particular, a pressure prevailing in the separation units falls along the row of separation units in the same direction in which the temperature in the separation units also falls.

In one embodiment, the recycling heat is in particular not fed back to the same separation unit from which it was taken from the thermal secondary energy, but rather fed back against the flow of heat by at least one separation unit, in particular a plurality of separation units. The compression heat pump advantageously raises the temperature level of the recycling heat, in particular when the heat pump heat is supplied, with the recycling heat being fed back counter to the temperature gradient at the same time.

According to one development of the invention, it is provided that the recycling heat of the secondary thermal energy is taken from a separation unit of the plurality of separation units that is the last separation unit along the heat flow - in particular from the last separation unit in the series of separation units along the temperature gradient, i.e. the separation unit with the lowest temperature level - and the High-temperature side of a along the heat flow first separation unit of the plurality of separation units - in particular along the temperature gradient first separation unit in the series of separation units, that is, the separation unit with the highest temperature level - is supplied.

According to a development of the invention, it is provided that the useful heat is supplied to the at least one separation unit via a heating medium. In particular, the useful heat of the at least one separation unit is supplied via steam, also referred to as heating steam, in particular steam, as the heating medium. It is possible that the useful heat of a separation unit does not include recycle heat. Alternatively, the useful heat of a separation unit comprises, in addition to heat provided elsewhere - e.g. embodied by steam from a boiler house - the recycle heat, in particular increased by the heat pump heat. As a further alternative, the useful heat consists of the recycling heat increased in particular by the heat pump heat; This means in particular that the useful heat only includes the sum of the recycling heat and the heat pump heat. In particular, the recycling heat - increased in particular by the heat from the heat pump - is supplied to the high-temperature side of the separation unit, embodied by a vapor which is generated using the recycling heat from a condensate of the same separation unit that is produced during separation from the heating medium - in particular from the same vapor.

Alternatively, it is provided that the useful heat is used to heat, in particular to superheat, the carbohydrate-water mixture upstream of an evaporation space of the at least one separation unit. In this embodiment, water evaporates from the heated, in particular superheated, carbohydrate-water mixture in the evaporation space, in particular when it enters the evaporation space, which is also referred to as the formation of flash steam. In particular, the pressure in the evaporation space is lower than the pressure at the point where the carbohydrate-water mixture is heated upstream of the evaporation space. According to one embodiment, the carbohydrate-water mixture is heated, in particular overheated, upstream of the separation unit. In this case, a superheating device that is set up to heat, in particular to superheat, the carbohydrate-water mixture upstream of the evaporation space is not itself part of the separation unit and rather is arranged upstream of the separation unit. According to this configuration, the useful heat of the separation unit is thus supplied, embodied by the carbohydrate-water mixture that is heated, in particular superheated, upstream of the separation unit. According to another embodiment, the carbohydrate-water mixture is heated, in particular overheated, in the separation unit upstream of the evaporation space. In this case the superheating device is part of the separation unit and is arranged in the separation unit upstream of the evaporation space. The useful heat is supplied to the carbohydrate-water mixture--either upstream of the separation unit or in the separation unit--in particular via a heat transport medium or heating medium, in particular water, steam or a thermal oil. In particular, the useful heat consists of the recycling heat increased in particular by the heat pump heat. Alternatively it is possible that the useful heat of a separation unit does not include any recycle heat. Further alternatively, the useful heat of a separation unit comprises, in addition to heat provided elsewhere - for example embodied by steam from a boiler house - the recycling heat, in particular increased by the heat pump heat.

According to a development of the invention, it is provided that the recycling heat is withdrawn from a waste stream carrying away the water separated from the carbohydrate-water mixture. Thus, advantageously, on the low-temperature side of a separation unit in the waste flow, dissipated heat embodied in the waste stream is returned to the high-temperature side of the separation unit or another separation unit, as a result of which the method proposed here is very efficient. At the same time, a material separation of the low-temperature side from the high-temperature side is achieved by means of the compression heat pump, whereby not part of the waste flow itself is returned, but only the recycling heat removed from the waste flow. The low-temperature side and the high-temperature side are therefore connected to one another only thermally, via a heat flow, with regard to the recirculation of the recycling heat, but are materially separated from one another.

In the context of the present technical teaching, a mass flow is understood to mean in particular a mass flow which comprises at least the water separated from the carbohydrate-water mixture in the separation unit, possibly plus entrained components of the carbohydrate-water mixture. In particular, the waste stream in the separation unit is steam formed from the carbohydrate-water mixture, moist air, in particular hot air, or in particular vapor. However, the mass flow can also be a condensate.

In one embodiment it is provided that the mass flow is fed at least partially directly to the first working medium heat exchanger—in particular the working medium evaporator—of the compression heat pump. In this way, the recycling heat can be taken from the mass flow directly in the first working medium heat exchanger.

In another embodiment, it is provided that the recycling heat from the mass flow is conveyed to the first working medium heat exchanger—in particular the working medium evaporator—via a first heat transport device. This allows in particular a spatial separation between the mass flow and the first working medium heat exchanger or the compression heat pump as a whole.

If the recycling heat is extracted from a condensate that is not a waste flow, it is also possible in this case for the condensate to be fed at least partially directly to the first working medium heat exchanger in a first embodiment, or for the recycling heat extracted from the condensate to be used in a second embodiment is fed to the first working medium heat exchanger mediated via a heat transport device.

In the context of the present technical teaching, a heat transport device is understood to mean a device that is set up to transport heat from a first location to another, second location that is at a distance from the first location. The heat transport device can in particular have at least one heat transport element, for example in the simplest configuration an ingot or rod made of a thermally conductive material. In a more complex configuration, the heat transport device has in particular at least one heat pipe, also referred to as a heat pipe. Alternatively or additionally, the heat transport device has at least one pipeline and/or a fitting, in particular at least one heat distributor. Alternatively or additionally, the heat transport device has at least one heat transport medium circuit, in particular with a liquid heat transport medium, with water or a heat transfer oil, for example, being provided as the heat transport medium. The heat transitions in the heat transport medium cycle can include phase transitions or be designed as sensitive heat transitions, ie without phase transitions.

According to a development of the invention, it is provided that the recycling heat is supplied to a heating mass flow which is supplied to the at least one separation unit on the high-temperature side in order to thermally separate the water from the carbohydrate-water mixture.

In the context of the present technical teaching, a heating mass flow is understood to mean a heat-carrying mass flow. The fact that the recycling heat is supplied to the heating mass flow means in particular that the thermal energy of the heating mass flow is increased by the recycling heat—in particular additionally by the heat pump heat.

In one embodiment of the method, the heating mass flow is the mass flow of a heating medium that is used to heat the carbohydrate-water mixture. In particular, it is possible for steam, in particular steam, or air, in particular hot air, or a heat transport medium to be used as the heating medium.

In another embodiment of the method, the heating mass flow is the mass flow of the carbohydrate-water mixture itself. In this case, the recycle heat is used in particular to heat or preheat, in particular to superheat, the carbohydrate-water mixture. In one embodiment, the carbohydrate-water mixture is then introduced into an evaporation chamber of the separation unit, where water suddenly evaporates from the carbohydrate-water mixture—in particular as so-called flash steam.

In one embodiment it is provided that at least a partial heating mass flow of the heating mass flow is conducted upstream of the separation unit through the second working medium heat exchanger—in particular the working medium condenser—of the compression heat pump. In this way, the recycling heat can be supplied to the heating mass flow directly from the second working medium heat exchanger. In one embodiment it is provided that the entire heating mass flow is conducted upstream of the separation unit through the second working medium heat exchanger; in particular, the carbohydrate-water mixture is fed directly through the second working medium heat exchanger.

In another embodiment, it is provided that the recycling heat is supplied to the heating mass flow from the second working medium heat exchanger—in particular the working medium condenser—via a second heat transport device. This allows in particular a spatial separation between the heating mass flow and the second working medium heat exchanger or the compression heat pump as a whole.

In one embodiment, an evaporation unit is used as the at least one separation unit. In another embodiment, a crystallization unit is used as the at least one separation unit.

According to one development of the invention, it is provided that at least one evaporation unit - as at least one first separation unit - and at least one crystallization unit - as at least one second separation unit - are used as the at least one separation unit, with secondary thermal energy being removed from the at least one evaporation unit, recycling heat which is fed back to the at least one evaporation unit by means of a first compression heat pump, and wherein secondary thermal energy is removed from the at least one crystallization unit for recycling heat, which is fed back to the at least one crystallization unit by means of a second compression heat pump. By using separate compression heat pumps for the at least one evaporation unit and thus a concentration or thickening process on the one hand and for the at least one crystallization unit and thus one crystallization process on the one hand, it is advantageously possible to optimize the thermal technology of the various processes at least largely independently of one another, in particular at different temperature levels to perform. In particular, a thermal decoupling of the concentration or thickening, in particular the production of thick juice from the carbohydrate-water mixture entering the process as thin juice, from the crystallization allows a particularly efficient process control of the concentration or thickening process, in particular because it no longer has to be guaranteed that at the end of which a sufficient amount of heat remains for crystallization. Rather, the process can advantageously be conducted in such a way that the initially introduced amount of heat is used as completely as possible in the process itself. In particular, the temperature level for the evaporation can be lowered, in particular - for example for a sucrose solution - from conventional 130 °C to 135 °C in the initial separation stage to around 120 °C, so that the thermal effect in particular is reduced and thus the risk of Discoloration of the resulting thick juice is reduced. In addition, by decoupling the crystallization, a sufficient amount of heat, in particular in the form of vapors, can easily be provided for use in the first compression heat pump. At the same time, the thermal decoupling of the various processes allows the temperature for the crystallization to be raised so that this can also be carried out under particularly favorable conditions. In particular, the (vapour) temperature for the crystallization can be raised, in particular - for example for sucrose crystallization - from conventionally about 60 ° C at 0.2 bar absolute to about 65 ° C at 0.25 bar absolute, which advantageously the Crystallization rate can be increased in particular to their maximum. In particular, a space/time yield in the sugar house can be increased. With a view to the overall process the total amount of heating steam to be supplied from the boiler house can advantageously be significantly reduced. In addition, the heating steam temperature for the crystallization can be selected independently of the design of the evaporation and can even be above 110 °C.

The determining parameter for the temperature selection in the at least one evaporation unit is no longer the crystallization, but rather the target temperature to be reached in the juice heating. Adjusted wiring of the evaporation units reduces the required heating steam temperatures, which also reduces the equivalent heat exposure time. The increased space/time yield in at least one crystallization unit (“sugar house”) is achieved on the one hand by the improved mass transfer to the crystal and on the other hand by an increase in the temperature differences due to higher initial temperatures of the magma in the cooling crystallization.

The procedure proposed here proves to be particularly advantageous in the production of crystalline sucrose or crystalline isomaltulose.

In one embodiment, the separating device has a plurality of evaporation units and exactly one crystallization unit.

According to a development of the invention, it is provided that a carbohydrate/water mixture from the at least one evaporation unit is supplied to the at least one crystallization unit. In particular, the carbohydrate-water mixture is first concentrated or thickened in the at least one evaporation unit, with a thick juice being produced in particular from a thin juice, with a carbohydrate contained in the concentrated carbohydrate-water mixture then being crystallized in the at least one crystallization unit , the carbohydrate being precipitated in particular from the thick juice. In particular, in the at least one crystallization unit, sucrose or isomaltulose is crystallized out of the concentrated carbohydrate-water mixture or thick juice, in particular a sugar solution.

In one embodiment, the crystallization unit and the evaporation unit are connected directly to one another via a product stream of the carbohydrate-water mixture. This allows in particular a continuous process control.

In another embodiment, the crystallization unit and the evaporation unit are separated from one another with respect to the product stream by an intermediate store for the carbohydrate-water mixture. The intermediate storage of the in particular concentrated or thickened carbohydrate-water mixture advantageously allows the various processes to be carried out independently of one another, in particular in a demand-controlled manner.

Alternatively or additionally, the at least one evaporation unit and the at least one crystallization unit, in particular the first compression heat pump and the second compression heat pump, are operated thermally separately from one another. This in particular allows thermal separation of the various processes from one another, combined with the advantages already explained.

Alternatively, it is possible for waste heat from the at least one evaporation unit, in particular embodied by a vapor from the at least one evaporation unit, to be used as a heat source for the second compression heat pump. This advantageously allows waste heat from the concentration or thickening process to be used in the crystallization process.

According to a development of the invention, it is provided that the compression heat pump is driven electrically. The reuse of waste heat as recycling heat with the simultaneous supply of heat pump heat mechanically generated via an electric drive advantageously enables a significant substitution and thus reduction, if necessary even avoidance, of useful heat initially fed into the process, thermally generated, in particular via the combustion of fossil fuels. In particular, an amount of steam initially fed into the process from a boiler house can be reduced - if necessary, in particular depending on the process, even reduced to zero - or the same amount of steam initially fed in from the boiler house can be significantly more efficient, in particular for the separation of a larger amount of water from the carbohydrate-water mixture, in particular for processing a larger quantity of carbohydrate-water mixture. Depending on the type of generation of the electrical energy for driving the compression heat pump, significant costs can be saved, but not least, significant carbon dioxide emissions can be saved. Thus, a significant decarbonization of the process can be achieved.

In one embodiment, the compression heat pump is driven with electrical energy from renewable sources. In particular In this case, the method proposed here has significantly lower carbon dioxide emissions than conventional methods for separating water from a carbohydrate-water mixture. In particular, heat provided thermally from fossil fuels is effectively replaced by heat provided mechanically via the electrically driven working medium compressor, which ultimately results from regenerative sources.

In another embodiment of the method, the compression heat pump is driven mechanically by a heat engine, in particular an internal combustion engine, in particular a gas turbine, in particular via a gearbox. This is also a very efficient and cheap way to mechanically provide heat for the separation of water from the carbohydrate-water mixture. In particular, the internal combustion engine, in particular the gas turbine, is operated with biogas or another fuel gas from a regenerative source, so that in this case too, significant carbon dioxide emissions are effectively saved and decarbonization effects are thus achieved.

According to one development of the invention, it is provided that a plurality of separation units are operated as the at least one separation unit, with a waste stream being removed from each separation unit of the plurality of separation units, with at least one of the waste streams being used as a heat source for a further process. Advantageously, heat comprised by the different mass flows can thus be used efficiently for other processes, for example for heating factory rooms or other industrial, chemical, biological and/or food technology processes--in particular in the same factory or plant.

Alternatively or additionally, at least one of the waste streams can be used as a heat source for preheating the carbohydrate-water mixture, in particular before the carbohydrate-water mixture enters a direction of flow of the carbohydrate-water mixture - i.e. along the direction defined by the product stream Order - first separation unit of the plurality of separation units.

The object is also achieved by creating a separation device for separating water from a carbohydrate-water mixture, which has at least one separation unit, the at least one separation unit having a product inlet for introducing the carbohydrate-water mixture into the separation unit and a product outlet for discharging a partially dewatered carbohydrate-water mixture, the separation unit being set up to separate water from the carbohydrate-water mixture, the at least one separation unit having a useful heat input on a high-temperature side for the supply of useful heat - as thermal primary energy - and on a low-temperature side has a secondary energy outlet for dissipating thermal secondary energy, wherein the separation device has a compression heat pump with a closed working medium circuit and is set up to remove recycling heat from the thermal secondary energy discharged via the secondary energy outlet and to extract the recycling heat from the useful heat inlet on the high-temperature side at a temperature level by means of the compression heat pump greater than 100 °C. In connection with the separating device, there are in particular the advantages that have already been explained in connection with the method.

In one embodiment, the separating device is set up to carry out a method according to the invention or a method according to one or more of the embodiments described above.

In particular, the separating device or elements of the separating device have at least one feature already explained above in connection with the separating device or an element of the separating device, or a combination of these features.

In one embodiment of the separation device, the product inlet and the useful heat inlet of the at least one separation unit are spatially and/or fluidically separated from one another. In particular, in this embodiment, the useful heat input is set up in order to introduce the useful heat, embodied by a heating medium as the heating mass flow, into the separation unit, the heating medium being in particular steam, in particular steam, air, in particular hot air, a heat transport medium, or a condensate from the heating that is, a condensate formed from the heating medium, which is vapors generated by the separation unit having useful heat input, that is, from the same separation unit.

In another embodiment of the separating device, the product input is identical to the useful heat input, in which case the useful heat embodied by the carbohydrate-water mixture itself is introduced into the separating unit as the heating mass flow. In particular, the carbohydrate-water Mixture heated in a superheating device of the separating device, in particular overheated, it then being introduced into an evaporation chamber of the separating unit, where water evaporates from the carbohydrate-water mixture, which is also referred to as flash steam, in particular abruptly.

In one embodiment, the separating device has a plurality of separating units. In one embodiment, the separating device exclusively has such separating units in which the product input is spatially and/or fluidically separated from the useful heat input. In another embodiment, the separating device exclusively has such separating units in which the product input is identical to the useful heat input. In yet another embodiment, the separating device has at least one first separating unit, in which the product input is separated spatially and/or in terms of flow from the useful heat input, the separating device also having at least one second separating unit, in which the product input is identical to the useful heat input.

In one embodiment, the separating device has only separating units, each with at least one heating surface. In another embodiment, the separating device has only separating units, each with an evaporation space. In yet another embodiment, the separating device has at least one separating unit with at least one heating surface and at least one further separating unit with an evaporation chamber.

The secondary energy outlet is set up in particular to dissipate the secondary thermal energy in the form of steam, in particular steam, in particular a vapor formed from the carbohydrate-water mixture, or in the form of hot air and/or in the form of a condensate.

In one embodiment, the separation device is set up to feed the recycling heat back to the useful heat input of the same separation unit on its high-temperature side.

In another embodiment, the separation device is set up to feed the recycling heat back to the useful heat input of a separation unit other than the separation unit from whose secondary energy output the recycling heat originates, on the high-temperature side. In particular, the separation device is set up to extract the recycling heat from a separation unit downstream along a heat flow through the separation device comprising a plurality of separation units and to supply it to a separation unit upstream along the heat flow.

In particular, the separating device has a plurality of separating units which are thermally connected to one another and arranged one behind the other in a row along a heat flow—in particular along a temperature gradient, and preferably additionally along a pressure gradient. The separation device is configured to extract the recycling heat of the secondary thermal energy on the low-temperature side of a downstream separation unit of the plurality of separation units and to supply it to the high-temperature side of an upstream separation unit of the plurality of separation units by means of the compression heat pump, the upstream separation unit being arranged upstream of the downstream separation unit along the heat flow is.

In particular, the downstream separation unit is a last separation unit of the plurality of separation units along the heat flow, and the upstream separation unit is a first separation unit of the plurality of separation units along the heat flow.

In particular, the secondary energy outlet is set up to discharge from the separation unit a waste stream carrying away the water separated from the carbohydrate-water mixture, in particular in the form of steam, in particular steam, in particular a vapor, or in the form of air, in particular moist hot air, and/or or in the form of a condensate.

In one embodiment, the secondary energy output is fluidically connected to the first working medium heat exchanger, in particular the working medium evaporator, of the compression heat pump, so that the recycling heat can be removed from the waste flow directly in the first working medium heat exchanger and used to evaporate the working medium.

In another embodiment, the separating device has a first heat transport device which is arranged and set up to thermally connect the waste flow to the first working medium heat exchanger, in particular the working medium evaporator.

In one embodiment, the useful heat input, or - in particular if the product input is identical to the useful heat input - the product input is fluidically connected to the second working medium heat exchanger, in particular the working medium condenser, of the compression heat pump, so that the recycling heat - in particular increased by the heat pump heat - At least a partial heating mass flow of the heating mass flow can be supplied upstream of the useful heat input or the product input directly in the second working medium heat exchanger, where it is released in particular as condensation heat of the working medium.

In another embodiment, the separating device has a second heat transport device, which is arranged and set up to thermally connect the useful heat input or the product input, and thus the heating mass flow, to the second working medium heat exchanger, in particular the working medium condenser.

In one embodiment, the separation device has an evaporation unit as the at least one separation unit. In another embodiment, the separation device has a crystallization unit as the at least one separation unit.

In one embodiment, the separating device has at least one evaporation unit as the at least one separating unit - as at least one first separating unit - and at least one crystallization unit - as at least one second separating unit -, the separating device being set up to extract recycling heat from thermal secondary energy of the at least one evaporation unit , and to feed the recycling heat back to the at least one evaporation unit by means of a first compression heat pump. The separation device is also set up to remove recycling heat from secondary thermal energy of the at least one crystallization unit and to feed the recycling heat back to the at least one crystallization unit by means of a second compression heat pump. In particular, as the compression heat pump, the disconnection device has the first compression heat pump on the one hand and the second compression heat pump on the other, ie in particular two compression heat pumps.

In one embodiment, the separating device has a plurality of evaporation units and exactly one crystallization unit.

In one embodiment of the separation device, the at least one crystallization unit is fluidically connected - in particular via a product line - to the at least one evaporation unit, so that the crystallization unit can be fed a carbohydrate-water mixture from the at least one evaporation unit directly via the fluidic connection for crystallization.

In another embodiment, the separating device has an intermediate store into which the carbohydrate-water mixture emerging from the at least one evaporation unit can be stored, wherein the carbohydrate-water mixture can be removed from the intermediate store and fed to the at least one crystallization unit for crystallization. In particular, the at least one evaporation unit and the at least one crystallization unit are fluidically separated from one another or at least not directly connected to one another, with mass transport of the carbohydrate-water mixture from the evaporation unit to the crystallization unit only being provided via the intermediate storage facility.

In one embodiment, the separation device is set up to operate the at least one evaporation unit and the at least one crystallization unit, in particular the first compression heat pump and the second compression heat pump, thermally separately from one another.

In another embodiment, the separation device is set up to use waste heat from the at least one evaporation unit as a heat source for the second heat pump. In particular, the separating device has a thermal connection - in particular in the form of a vapor line - between the at least one evaporation unit and the second compression heat pump, in particular the first working medium heat exchanger, in particular the working medium evaporator of the second compression heat pump.

In one embodiment of the separation device, the compression heat pump has an electrical machine, in particular an electric motor, as a drive for the working medium compressor. In particular, the compression heat pump is set up to be operated with electrical energy from renewable sources.

In another embodiment of the separating device, the compression heat pump is driven by a heat engine—preferably via a gear tied. In one embodiment, the heat engine is designed as an internal combustion engine, in particular as a gas turbine, and is preferably set up to be operated with biogas or another fuel gas from regenerative sources.

In one embodiment, the separating device has a plurality of separating units, with each separating unit of the plurality of separating units being assigned a waste flow discharge line which is thermally connected to at least one further process, so that at least one of the waste flows of the separating units can be used as a heat source for a further process can be used.

• 1 ein erstes Ausführungsbeispiel eines Verfahrens und einer Abtrennvorrichtung zum Abtrennen von Wasser aus einem Kohlenhydrat-Wasser-Gemisch;
• 2 ein zweites Ausführungsbeispiel eines Verfahrens und einer Abtrennvorrichtung zum Abtrennen von Wasser aus einem Kohlenhydrat-Wasser-Gemisch;
• 3 ein drittes Ausführungsbeispiel eines Verfahrens und einer Abtrennvorrichtung zum Abtrennen von Wasser aus einem Kohlenhydrat-Wasser-Gemisch;
• 4 ein viertes Ausführungsbeispiel eines Verfahrens und einer Abtrennvorrichtung zum Abtrennen von Wasser aus einem Kohlenhydrat-Wasser-Gemisch, und
• 5 ein fünftes Ausführungsbeispiel eines Verfahrens und einer Abtrennvorrichtung zum Abtrennen von Wasser aus einem Kohlenhydrat-Wasser-Gemisch.

The invention is explained in more detail below with reference to the drawing. show:

• 1 a first embodiment of a method and a separation device for separating water from a carbohydrate-water mixture;
• 2 a second embodiment of a method and a separation device for separating water from a carbohydrate-water mixture;
• 3 a third embodiment of a method and a separating device for separating water from a carbohydrate-water mixture;
• 4 a fourth exemplary embodiment of a method and a separating device for separating water from a carbohydrate-water mixture, and
• 5 a fifth embodiment of a method and a separation device for separating water from a carbohydrate-water mixture.

In general, the following system of variables is introduced in the figures for the purpose of describing the various exemplary embodiments: A specific separation unit or thermal separation stage, on the low-temperature side of which recycling heat is removed, is denoted by the variable x, which can assume values from 1 to n, where n is the is the total number of separation units included in a separation device under consideration and integrated into a common heat flow. The thermal secondary energy removed on the low-temperature side of the separation unit x, embodied in particular by a vapor, is denoted by B _x . The useful heat supplied on the high-temperature side of a separation unit, which at least partially comprises the recirculated recycling heat - in particular again embodied by a vapor - is denoted by B _xy , where y denotes the number of separation units including the separation unit from which the recycling heat is removed, by which the recycle heat is returned. If the recycling heat is returned directly from the low-temperature side of a separation unit to the high-temperature side of the same separation unit, y=1 accordingly applies. A heating condensate of separation unit x is denoted by K _x-1 . A product condensate of the separation unit x is denoted by K _x .

In particular, the useful heat B _xy comprising at least part of the recycling heat removed from the separation unit x and recirculated by y stages is generally fed to the separation unit x-y+1. A heating condensate K _xy , a vapor B _x-y+1 and a product condensate K _x-y+1 occur in this separation unit x-y+1 . Useful heat in the form of a vapor B _x-1 is supplied to the separation unit x; there falls a heating condensate K _x-1 and a vapor B _x . The product condensate of the vapor B _x is referred to as K _x .

In particular, the invention integrates a closed, left-handed heat pump cycle process in which a vapor B _x is condensed as a heat source in order to feed a heating steam B _xy for heating to a heating element of an upstream stage xy. The heat provided by the working media circuit on the high-pressure side is transferred in the working media condenser to a condensate stream from stage x-y+1 (K _xy ), which leads to its evaporation. This additionally generated amount of heating steam B _xy is supplied to the heating element of the stage. The heat fed back from stage x to stage x-y+1 brings about a change in the evaporation capacity. This can be influenced by the amount of working medium circulated in the compression heat pump. An adjustment of the dry substance content is therefore possible without material return transport of a heating medium or vapor when selecting the parameter y.

The closed heat pump circuit increases the energy content of the vapor B _x from the separation stage x using mechanical energy to the exergetic level of a vapor quality that precedes by y stages and is therefore exergetically higher. The heating element of stage x-y+1, which is heated by the heating steam B _xy , can also have different quality requirements for the heat transfer medium of the heating steam compared to the heat source, which represents the energy content of the vapor B _x , since in the closed heat pump circuit only an energy and no mass transport from the heat mequelle B _x to heat sink B _xy takes place. Equally, instead of vapours, however, any form of liquid heat source - in particular a condensate K _x - can be available from any utilization stage x, in which the heat is transferred by cooling the liquid.

1 now shows a first embodiment of a method and a separation device 1 for separating water from a carbohydrate-water mixture.

The separation device 1 has a separation unit 3 which in turn has a product inlet 5 for introducing the carbohydrate-water mixture 4 into the separation unit 3 and a product outlet 7 for discharging a partially dewatered carbohydrate-water mixture 4 . In this case, the separation unit 3 is set up to separate water from the carbohydrate/water mixture. The separation unit 3 has a useful heat input 11 on a high-temperature side 9 for the supply of useful heat and a secondary energy output 15 for dissipating thermal secondary energy on a low-temperature side 13 . Furthermore, the separation device 1 has a compression heat pump 17 with a closed working medium circuit 19 and is set up to extract recycling heat from the thermal secondary energy discharged via the secondary energy outlet 15 and to transfer the recycling heat to the useful heat inlet 11 on the high-temperature side 9 by means of the compression heat pump 17 at a temperature level greater than 100 °C to be supplied again.

The first embodiment of the separating device 1 is arranged to separate water from moisture-containing crop pieces as the carbohydrate-water mixture 4, in particular sugar beet cossettes or chicory roots. In particular, the separating device 1 is set up for drying chips in a sugar factory.

The first exemplary embodiment of the separating device 1 also has a drying stage 21 upstream of the separating unit 3 along a product flow of the carbohydrate-water mixture 4; however, this can also be omitted in another exemplary embodiment and is therefore optional.

The compression heat pump 17 has - in particular in the specified order along a flow direction of a working medium in the closed working medium circuit 19 - an expansion valve 23 for expanding the working medium, a first working medium heat exchanger 25, in particular a working medium evaporator 27, a working medium compressor 29, here two working fluid compressors 29 connected in parallel in terms of flow, and a second working fluid heat exchanger 31, in particular a working fluid condenser 33.

In the first exemplary embodiment of the separating device 1 and thus of the method at the same time, the useful heat of the separating unit 3 is supplied via a heating medium 34 , here via supply air 35 . The recycling heat is withdrawn from a waste stream 37, in this case waste air 39, which removes the water separated from the carbohydrate-water mixture. The mass flow 37 is in this case fed directly to the first working medium heat exchanger 25, that is to say the working medium evaporator 27, in order to remove the recycling heat. Alternatively, it is possible in another exemplary embodiment that the recycling heat from the mass flow 37 is conveyed to the first working medium heat exchanger 25 via a first heat transport device.

The recycling heat is fed to a heating mass flow, here the mass flow of the heating medium 34, i.e. the supply air 35, with the heating mass flow being fed to the separation unit 3 on its high-temperature side 9 in order to thermally separate the water from the carbohydrate-water mixture 4. The recycling heat is conveyed to the heating mass flow, i.e. in the first exemplary embodiment the supply air 35, from the second working medium heat exchanger 31, in particular the working medium condenser 33, via a heat transport device 41, here to distinguish it from the above-mentioned first heat transport device as the second heat transport device 41 designated supplied. The second heat transport device 41 has a heat transport medium circuit 43, in particular with a liquid heat transport medium, it being possible for water or a heat transfer oil, for example, to be provided as the heat transport medium. The heat transport medium circuit 43 comprises a third heat exchanger 45 through which the heat transport medium flows on the one hand and the heating medium on the other hand, with the recycling heat—particularly increased by the heat pump heat—being transferred to the heating medium 34. Alternatively, it is possible in another initial example for at least a partial heating mass flow of the heating mass flow to be routed through the second working medium heat exchanger 31 upstream of the separation unit 3 .

The compression heat pump 17, in particular the working media compressor 29 are at the first embodiment shown here each driven by an electric machine 44, in particular an electric motor. They are preferably driven with electrical energy from regenerative sources. Advantageously, heat otherwise provided from chemical energy, in particular by burning fossil fuels, can thus be replaced by mechanically generated heat, in particular using electrical energy—in particular from regenerative sources—mechanically generated heat.

In the first exemplary embodiment, the useful heat supplied during operation of the separation unit 3 preferably consists entirely of the recycling heat—augmented by the heat pump heat. No further supply of heat is then required while the disconnecting device 1 is in operation. To start up the separating device 1, however, external heat can be supplied, for example by means of an electric air heater, until a sufficient amount of heat is available in the waste mass flow 37 for the removal of recycling heat in autonomous operation.

In particular, the crop pieces are fed to the separating device 1 with a mass flow of 45 t/h at a dry matter content of 32%. After passing through the upstream drying stage 21, a mass flow of 20 t/h of crop pieces with a dry matter content of 70% results, which enters the separation unit 3 via the product inlet 5. A mass flow of 138,000 m ³ /h supply air 35 is introduced into the separation unit 7 via the useful heat input 11, the supply air 35 having previously been in the third heat exchanger 45 from 7 °C with a relative humidity of 77% to 100 °C with a relative humidity is heated by 0.8%.

A mass flow of 16 t/h of crop pieces with a dry matter content of 90% is discharged from product outlet 7.

The mass flow 37 has a temperature of 30° C. and a relative humidity of 99.9%. After passing through the first working medium heat exchanger 25 with the release of the recycling heat, the waste stream 37 still has a temperature of 25° C. with a relative humidity of 99.9%.

The total electrical output of the working medium compressors 29, in particular the electrical machines 44, is 2 MW - preferably 1 MW per working medium heat exchanger 29.

The heat transport medium in the heat transport medium circuit 43 preferably has a temperature of 105 °C everywhere along the heat transport medium circuit 43 during operation and is evaporated in the second working medium heat exchanger 31, with condensation heat being extracted from the working medium and fed to the heat transport medium as evaporation heat becomes. The heat transport medium is condensed in the third heat exchanger 45, heat of condensation being extracted from it and fed to the heating medium 34. In an alternative embodiment, however, sensitive heat transfers without phase transitions of the heat transfer medium are also possible, in particular if the heat transfer medium is designed as heat transfer oil.

Since the separating device 1 in the first exemplary embodiment has only one separating unit 3, from the low-temperature side 13 of which the recycling heat is returned to its own high-temperature side 9, x=1, y=1, n=1, and _Bxy = B ₀ . The thermal secondary energy is correspondingly denoted by B ₁ .

2 shows a second embodiment of a method and a separation device 1 for separating water from a carbohydrate-water mixture 4.

Elements that are the same and have the same function are provided with the same reference symbols in all figures, so that reference is made to the previous description in each case.

The second exemplary embodiment of the separating device 1 is set up to separate water from a sucrose-containing solution, in particular from thin juice for the production of sucrose.

In particular, the separating device 1 according to the second embodiment is designed as an evaporation station of a sugar factory.

The separation device 1 according to the second exemplary embodiment has a plurality of separation units 3, here in particular four separation units 3, which are thermally connected to one another and arranged in series along a heat flow, in particular along a temperature gradient and along a pressure gradient. In the row of separating units 3, the temperature and the pressure are highest in a first separating unit 3.1, with both the pressure and the temperature along the row of separating units 3 via a second separating unit 3.2 and a third separating unit 3.3 up to a fourth Remove separation unit 3.4 so that the temperature and pressure in the fourth separation unit 3.4 are lowest.

In this exemplary embodiment, the separation units 3 are designed as evaporation units.

The useful heat is first supplied to the first separation unit 3.1 via a heating medium 34, in this case heating steam 48, in particular steam, which in particular includes boiler house heating steam 49 coming partially from a boiler house 47. The recycling heat is taken from the secondary thermal energy on the low-temperature side 13 of a downstream separation unit 3 of the plurality of separation units 3, here specifically a fourth low-temperature side 13.4 of the fourth separation unit 3.4, and is transferred by means of the compression heat pump 17 to the high-temperature side 9 of an upstream separation unit 3 of the plurality of separation units 3, here specifically a first high-temperature side 9.1 of the first separation unit 3.1; according to the above, the first, upstream separation unit 3.1 is arranged along the heat flow upstream of the fourth, downstream separation unit 3.4. In particular, in this second exemplary embodiment, the recycling heat of the secondary thermal energy is taken from the last separation unit 3.4 of the plurality of separation units 3 along the heat flow and fed to the high-temperature side 9.1 of the first separation unit 3.1 of the plurality of separation units 3 along the heat flow.

In particular, the recycling heat is supplied to the heating mass flow of the heating medium 34, here the boiler house heating steam 49, namely mediated via the second heat transport device 41 from the second working medium heat exchanger 31 of the compression heat pump 17.

The separation units 3 each have at least one heating surface 51, preferably a plurality of heating surfaces 51, which are acted upon by the heating steam 48 on a heating medium side 53 and are in thermal contact with the carbohydrate-water mixture 4 on a product side 55 remote from the heating medium side 53 , especially in physical contact. In particular, the at least one heating surface 51 of the first separation unit 3.1 is acted upon by the heating medium 34, which condenses on the heating surface 51 to form a heating condensate 57 and gives off the heat of condensation to the carbohydrate/water mixture 4. The resulting heating condensate 57 of the first separation unit 1 is fed at least in part to the second working medium heat exchanger 31 of the compression heat pump 17 by means of the second heat transport device 41, where it is again evaporated and then fed to the boiler house heating steam 49 as recycling steam 59. The heating steam 48 fed to the first separating unit 3.1 thus comprises partly the boiler house heating steam 49 flowing in from the boiler house 47 and partly the recycling steam 59 formed from the heating condensate 57.

The heating condensate 57 is preferably initially collected in a collection container 61 . A dividing device 63, which can in particular be designed as a pump or as a valve, preferably specifies which proportion of the heating condensate 57 is fed to the second working medium heat exchanger 31. The remaining portion of the heating condensate 57 that is not fed to the second working medium heat exchanger 31 is preferably fed—particularly after cooling in a cooler 65—to a feedwater tank 67 of a steam generator of the boiler house 47 (not shown).

The recycling heat is extracted from the waste stream 37, here a vapour, removing the water separated from the carbohydrate-water mixture 4 in the fourth separation unit 3.4, with the waste stream 37 being fed at least partially directly to the first working medium heat exchanger 25 of the compression heat pump 17. In the first working medium heat exchanger, the vapor is condensed to form a product condensate 69, which is finally discharged—particularly for further use as a heat source in other processes. The compression heat pump 17 provides a material separation of the fourth low-temperature side 13.4 of the fourth separating unit 3.4 from the first high-temperature side 9.1 of the first separating unit 3.1, with these only being thermally connected to one another via the compression heat pump 17. In this way, mixing of the product condensate 69 with the heating condensate 57 is advantageously avoided.

In each of the separation units 3, a vapor is produced by separating the water from the carbohydrate-water mixture 4. According to the system of variables explained above, x=4, y=4 and n=4, so the heating steam 48 is denoted by B _xy =B ₀ , the first vapor from the first separation unit 3.1 by B ₁ , the second vapor from the second separation unit 3.2 with B ₂ , third vapor from the third separation unit 3.3 as B ₃ , and finally the fourth vapor from the fourth separation unit 3.4 with B ₄ , the fourth vapor B ₄ being the waste stream 37 . The first separation unit 3.1 Subsequent separation units 3 are each heated by the vapor of the immediately preceding separation unit 3--heating medium carrying useful heat. The secondary thermal energy of an immediately preceding separation unit 3 is therefore at the same time at least partly the useful heat of the immediately following separation unit 3. A condensate is produced in each of the separation units 3, with the condensates analogous to the designation of the vapors as K ₀ , K ₁ , K ₂ , and K ₃ . In particular, the second to fourth condensates K ₁ , K ₂ , and K ₃ are each simultaneously product condensates of the separation unit 3.1, 3.2, 3.3 with the same designation according to the index and heating condensates of the immediately following separation unit 3.2, 3.3, 3.4 with index increased by 1. The first condensate K ₀ occurring at the first separation unit 3.1 is the heating condensate 57. A fifth condensate K ₄ of the fourth vapor B ₄ is the product condensate 69. The condensates K ₀ , K ₁ , K ₂ , K ₃ , K ₄ are each collected in collection containers 61 and finally discharged—particularly for further use as a heat source in other processes.

The vapors B ₁ , B ₂ and B ₃ are preferably used proportionately for preheating the carbohydrate-water mixture 4 in heaters 71, in addition to heating the separation unit 3 immediately following in each case. Furthermore, they are preferably proportionately - condensed in the collecting containers 61 and correspondingly discharged as condensate - in particular to a remaining proportion. The fourth vapor B ₄ is preferably used proportionally for further heat applications, for example for juice purification, in particular raw juice, or for diffusion. The separating device 1 is preferably operated in such a way that no portion of the fourth vapor B ₄ that needs to be recooled remains while the compression heat pump 17 is in operation. In particular, the first working medium heat exchanger 25 as a heat sink provides the driving force for the process. If, however, a portion to be re-cooled remains—in particular when the separating device 1 is started up or shut down—this is preferably fed to a cooling tower 73 in order to provide sufficient driving force for the evaporation process. The supply line to the cooling tower 73 can in particular be opened or closed as required via a valve device 75 . In particular, the valve device 75 is closed during continuous operation and can be opened in particular to start up the separation device 1 and in particular can remain open until the compression heat pump 17 can completely remove the remaining waste heat of the fourth vapor B ₄ apart from the further heat uses.

In particular, a waste stream 37 in the form of the respective vapor B ₁ , B ₂ , B ₃ , B ₄ is removed from each separation unit 3 of the plurality of separation units 3 , with at least one of the waste flows 37 , in particular each waste flow 37 , as a heat source for a further process is used.

In the second exemplary embodiment shown here, the product flow of the carbohydrate-water mixture 4 is designed parallel and in the same direction as the heat flow: The carbohydrate-water mixture 4 first flows into the first separation unit 3.1 as a thin juice and then runs through the second separation unit 3.2, the third separation unit 3.3 and finally the fourth separation unit 3.4, which it then leaves concentrated as thick juice.

In particular, the exemplary embodiment of the separation device 1 shown here is operated with the following parameters: 525 t/h of thin juice with a dry substance content of 18% are fed to the first separation unit 3.1 as the carbohydrate-water mixture 4, with the evaporation process taking place in the four separation units 3 is conducted in such a way that a mass flow of 124 t/h thick juice with a dry matter content of 72% results from the fourth separation unit 3.4.

While a conventional separation device 1 with a directly connected and thermally connected crystallization unit and six separation units 3 for the corresponding separation and crystallization capacity, a mass flow of 100 t/h of heating steam from the boiler house 47 at a temperature level of 130 °C to 135 °C would have to be supplied, only a mass flow of 41 t/h boiler house heating steam 49 from the boiler house 47 at a temperature level of 120° C. at 1.96 bar absolute is fed to the separation device 1 shown here with its only four separation units 3 . Energy is thus advantageously saved in two respects: on the one hand, with regard to the amount of steam to be generated in the boiler house 47, on the other hand, with regard to the steam temperature, as a result of which a significantly reduced use of, in particular, fossil chemical combustion energy for steam generation is necessary; on the other hand, the risk of unwanted discoloration of the thick juice during the drying process is effectively reduced due to the lower thermal effect at the reduced temperature. In addition, 68 t/h of recycling steam 59 at a temperature of 120° C. at 1.96 bar absolute are brought in from the second working medium heat exchanger 31, so that the first separation unit 3.1 receives a total of 109 t/h of heating steam 48 at 120° C. and 1.96 bar absolute as the heating medium 34. The energy for generating the recycling steam 59 is taken from the mass flow 37 and thus the fourth vapor B ₄ in the first working medium heat exchanger 25, which has a total mass flow of 93.5 t/h at a temperature of 95 °C and a Has a pressure of 0.84 bar absolute, of which 56.5 t/h are supplied to the first working media heat exchanger 25 and 37 t/h to the further heat uses. On the other hand, the energy comes from electrical power with which the working medium compressors 29 are operated, here a total of 6 MW. The reduction in the number of separation units compared to a conventional process makes it particularly advantageous to maintain a high steam temperature downstream of the last separation unit. so that sufficient recycle heat can be extracted.

3 shows a third exemplary embodiment of a method and a separating device 1 for separating water from a carbohydrate-water mixture 4. The fourth exemplary embodiment of the separating device 1 is set up to crystallize sucrose from thick juice or syrup by separating water from the thick juice or syrup . In particular, the separating device 1 according to the third embodiment is designed as a crystallization unit of a sugar factory.

In particular, the separating device 1 according to this exemplary embodiment has exactly one separating unit 3 designed as a crystallization unit.

In this third exemplary embodiment, during operation of the separating device 1 of the separating unit 3 on its high-temperature side 9, only recycling heat in the form of recycling steam 59 is supplied as useful heat—increased by the heat pump heat; the useful heat consists in any case during operation of the recycling heat - increased by the heat pump heat - so that the energy required for the operation of the separation device 1, at least during operation, consists exclusively of the electrical power supplied to the working medium compressors 29, here 8 MW, originates. To start up the separating device 1 , heating steam can be fed in via a steam valve 77 in a manner that is not explicitly shown here, until the thermal secondary energy available on the low-temperature side 13 is sufficient for the autonomous operation of the separating device 1 . The recycling steam 59 is generated directly from the heating condensate 57 in the second working medium heat exchanger 31 . The recycling steam 59 therefore condenses on the heating surface 51 of the separation unit 3 to form the heating condensate 57 and gives off condensation heat to the carbohydrate-water mixture 4, and the heating condensate 57 in turn becomes the recycling steam 59 in the second working medium heat exchanger 31 evaporated. The temperature preferably remains at least approximately constant along this cycle, an energy exchange or heat flow only takes place in the form of condensation heat in the separation unit 3 - with evaporation of water from the carbohydrate-water mixture 4 - and evaporation heat in the second working medium heat exchanger 31 - with condensation of the working medium - instead.

The recycling heat is removed from part of the waste stream 37 occurring as vapors in the first working medium heat exchanger 25 . The resulting product condensate 69 is preferably used to preheat raw juice from the sugar factory. Another part of the waste stream 37 is preferably used for the direct heating of thick juice and/or raw juice, with the vapor first being condensed in a pre-condenser shown as a first cooling tower 73.1, with the resulting mixture of condensate and cooling water then going to the corresponding heat sink, i.e. the thick juice -Warming and/or the raw juice warming is supplied. The valve device 75 is preferably closed during operation, but can be opened in particular to start up the separating device 1 in order to supply heat that has not been removed to a second cooling tower 73.2.

According to the system of variables discussed above, x=1, y=1, n=1 and the recycle vapor 59 is denoted as B _xy = B ₀ . The vapor occurring as the mass flow 37 is correspondingly denoted by B ₁ . The heating condensate 57 is denoted as K ₀ and the product condensate 69 as K ₁ .

In particular, the separation unit 3 is supplied with a mass flow of 51 t/h of recycling steam 59 at 102° C. and 1.09 bar absolute. The mass flow 37 is 36 t/h and leaves the separation unit 3 at a temperature of 65° C. and an absolute pressure of 0.25 bar. At the location of the first working medium heat exchanger 25, it still has a temperature of 60°C.

In an exemplary embodiment that is not explicitly shown, but which can be thought of as a combination of the second exemplary embodiment and the third exemplary embodiment, the separating device 1 has at least one evaporation unit as at least one first separating unit, in particular the four separating units 3 of the second exemplary embodiment, and additionally at least one crystallization unit, in particular the separation unit 3 of the third exemplary embodiment, as at least one second separation unit. In this case, recycling heat is extracted from the thermal secondary energy of the at least one evaporation unit, which is fed back to the at least one evaporation unit by means of a first compression heat pump, wherein at the same time recycling heat is extracted from the secondary thermal energy of the at least one crystallization unit, which is fed back to the at least one crystallization unit by means of a second compression heat pump .

In particular, the carbohydrate-water mixture 4 from the at least one evaporation unit is supplied to the at least one crystallization unit—directly or via an intermediate storage facility—that is to say, in particular, the thick juice. In particular, the at least one evaporation unit and the at least one crystallization unit, in particular the first compression heat pump and the second compression heat pump, are operated thermally separately from one another.

4 shows a fourth embodiment of a method and a separating device 1 for separating water from a carbohydrate-water mixture 4. The fourth embodiment of the separating device 1 is set up to separate water from a starch-containing medium as the carbohydrate-water mixture 4. In particular, the separating device 1 is set up as an evaporation station of a starch factory.

The separation device 1 according to the fourth exemplary embodiment has a plurality of separation units 3, here in particular four separation units 3, which are thermally connected to one another and arranged in series along a heat flow, in particular along a temperature gradient and along a pressure gradient. In the row of separating units 3, the temperature and the pressure are highest in a first separating unit 3.1, with both the pressure and the temperature along the row of separating units 3 via a second separating unit 3.2 and a third separating unit 3.3 up to a fourth Remove separation unit 3.4 so that the temperature and pressure in the fourth separation unit 3.4 are lowest.

The separation units 3 are designed as evaporation units in the fourth exemplary embodiment as well.

Also in the fourth exemplary embodiment, during operation of the separating device 1 of the first separating unit 3.1 on its first high-temperature side 9.1, only recycling heat in the form of recycling steam 59 is supplied as useful heat; the useful heat consists of the recycling heat at least during operation, so that the energy required to operate the separation device 1, at least during operation, comes exclusively from the electrical power supplied to the working medium compressors 29, here 1.6 MW. Boiler house heating steam 49 can be fed in from a boiler house 47 in particular for starting up the separation device 1 until the thermal secondary energy available on the fourth low-temperature side 13.4 of the fourth separation unit 3.4 is sufficient for the autonomous operation of the separation device 1. The recycling steam 59 is generated directly from a heating condensate 57 in the second working medium heat exchanger 31 . The recycling steam 59 condenses on the heating surface 51 of the first separation unit 3.1 to form the heating condensate 57 and gives off condensation heat to the carbohydrate-water mixture 4, and the heating condensate 57 in turn becomes the recycling steam 59 in the second working medium heat exchanger 31 evaporated. The temperature preferably remains at least approximately constant along this circuit.

The heating condensate 57 is preferably initially collected in a collection container 61 .

The recycling heat is extracted from the waste stream 37, here a vapour, removing the water separated from the carbohydrate-water mixture 4 in the fourth separation unit 3.4, with the waste stream 37 being fed at least partially directly to the first working medium heat exchanger 25 of the compression heat pump 17. In the first working medium heat exchanger 25, the vapor is condensed to form a product condensate 69, which is finally discharged—particularly for further use as a heat source in other processes. The compression heat pump 17 provides a material separation of the fourth low-temperature side 13.4 of the fourth separating unit 3.4 from the first high-temperature side 9.1 of the first separating unit 3.1, with these only being thermally connected to one another via the compression heat pump 17. In this way, mixing of the product condensate 69 with the heating condensate 57 is advantageously avoided.

In each of the separation units 3, a vapor is produced by separating the water from the carbohydrate-water mixture 4. According to the system of variables explained above, x=4, y=4 and n=4, so the heating steam 48 is denoted by B _xy =B ₀ , the first vapor from the first separation 3.1 with B ₁ , the second vapor from the second separation unit 3.2 with B ₂ , third vapor from the third separation unit 3.3 as B ₃ , and finally the fourth vapor from the fourth separation unit 3.4 with B ₄ , the fourth vapor B ₄ being the waste stream 37 . The separation units 3 following the first separation unit 3.1 are each heated by the vapor from the immediately preceding separation unit 3. A condensate is produced in each of the separation units 3, the condensates being referred to as K ₀ , K ₁ , K ₂ and K ₃ , analogously to the designation of the vapors. In particular, the second to fourth condensates K ₁ , K ₂ , and K ₃ are each simultaneously product condensates of the separation unit 3.1, 3.2, 3.3 with the same designation according to the index and heating condensates of the immediately following separation unit 3.2, 3.3, 3.4 with index increased by 1. The first condensate K ₀ occurring at the first separation unit 3.1 is the heating condensate 57. A fifth condensate K ₄ of the fourth vapor B ₄ is the product condensate 69.

In addition to heating the third separation unit 3.3, the second vapor B ₂ is used proportionately for preheating the carbohydrate/water mixture 4 in a first heater 71.1. The heating steam 48 is used proportionately in a second heater 71.2 for intermediate heating of the carbohydrate-water mixture 4.

The separating device 1 is preferably operated in such a way that during operation of the compression heat pump 17 a proportion of 2.9 t/h of the fourth vapor B ₄ remains to be recooled, in particular since there are no other consumers or heat sinks in this exemplary embodiment. This portion to be re-cooled is preferably fed to a cooling tower 73, in particular in order to provide sufficient driving force for the evaporation process to achieve the desired dry matter content. The supply line to the cooling tower 73 can in particular be opened or closed as required via a valve device 75 .

In the fourth exemplary embodiment shown here, the product flow of the carbohydrate-water mixture 4 is not designed along the heat flow: the carbohydrate-water mixture 4 first flows into the third separation unit 3.3 and then runs through the fourth separation unit 3.4 in the order given, the second separation unit 3.2 and finally the first separation unit 3.1, which it then leaves in concentrated form. Between the fourth separation unit 3.4 and the second separation unit 3.2, the carbohydrate-water mixture 4 is intermediately heated by means of a portion of the second vapor B ₂ in the first heater 71.1. Between the second separation unit 3.2 and the first separation unit 3.1, the carbohydrate-water mixture 4 is intermediately heated by means of a portion of the heating steam 48 in the second heater 71.2. In particular, the sequence of the separation units 3 along the product stream and the heaters 71 ensure that the carbohydrate-water mixture 4 remains sufficiently flowable when it is concentrated.

In particular, the exemplary embodiment of the separation device 1 shown here is operated with the following parameters: The third separation unit 3.3 is supplied with 43 t/h of syrup with a dry matter content of 32% as the carbohydrate-water mixture 4, with the evaporation process taking place in the four separation units 3 is conducted in such a way that a mass flow of 17 t/h of concentrated syrup with a dry substance content of 81% results from the first separation unit 3.1.

6.8 t/h of recycling steam 59 at a temperature level of 105° C. at 1.2 bar absolute are fed to the separation device 1 . The fourth vapor B ₄ occurs with a mass flow of 7.4 t/h at a temperature level of 48° C. and a pressure of 0.11 bar absolute, of which 4.5 t/h are routed to the first working medium heat exchanger 25 . The remaining 2.9 t/h are supplied to the cooling tower 73, in particular via the valve device 75.

5 shows a fifth exemplary embodiment of a method and a separating device 1 for separating water from a carbohydrate-water mixture 4. The fifth exemplary embodiment of the separating device 1 is set up to separate water from a stillage from bio-alcohol production as the carbohydrate-water mixture 4 to separate

The separating device 1 according to the fifth exemplary embodiment has a plurality of separating units 3, here in particular four separating units 3, with at least the first three separating units 3.1, 3.2 and 3.3 being thermally connected to one another. These three separation units 3.1, 3.2, 3.3 are arranged in series along a heat flow, in particular along a temperature gradient and along a pressure gradient. In the row of separating units 3, the temperature and the pressure are highest in a first separating unit 3.1, with both the pressure and the temperature decreasing along the row of separating units 3 via the second separating unit 3.2 to the third separating unit 3.3 men, so that the temperature and the pressure in the third separation unit 3.3 are lowest.

The fourth separation unit 3.4 is separated from the heat flow of the other separation units 3 and heated separately, in particular by means of boiler house heating steam 49 as a carrier of useful heat from a boiler house 47. A waste flow 37 assigned to this fourth separation unit 3.4 and therefore referred to as fourth waste flow 37.4 is at least for the most part discharged to a cooling tower 73 in the exemplary embodiment shown here, but can at least partly also be fed to the first working medium heat exchanger 25, so that this fourth Mass flow 37.4 recycling heat can be removed for the operation of the other separation units 3. In this way, the fourth separation unit 3.4 is then thermally connected to the remaining separation units 3.

The separation units 3 are designed as evaporation units in the fifth exemplary embodiment as well.

In the fifth exemplary embodiment as well, only recycling heat in the form of recycling steam 59 is supplied as useful heat during operation of the separating device 1 of the first separating unit 3.1 on its first high-temperature side 9.1.

The first, second and third separation unit 3.1, 3.2, 3.3 each have an evaporation chamber 79 which is arranged and set up in such a way that in the evaporation chamber 79 an - in particular abrupt or sudden - evaporation of water from the superheated carbohydrate-water mixture 4 , in particular in the form of flash vapor formation. Upstream of the evaporation chamber, the first, second and third separation units 3.1, 3.2, 3.3 each have an overheating device 81, which is set up to overheat the carbohydrate-water mixture 4 before it enters the respective evaporation chamber 79 a pressure that is lower than the pressure that prevails upstream of the respective evaporation space 79--in particular in the respectively associated overheating device 81.

The useful heat is thus supplied to the respective high-temperature side 9 by overheating the carbohydrate-water mixture 4 .

In particular, the recycle steam 59 is at least partially fed—to a first proportion—to the first superheating device 81.1 of the first separation unit 3.1, where it condenses so that its heat of condensation is used to superheat the carbohydrate-water mixture 4. A heating condensate 57 produced in this way is conducted into the second working medium heat exchanger 31 of the compression heat pump 17 and vaporized there, from which the recycling vapor 59 is produced in turn. A second portion of the recycling steam 59 is preferably used in a first additional superheater 83.1 of the first separation unit 3.1 for superheating the carbohydrate-water mixture 4. A third portion of the recycling steam 59 is preferably used in a second additional superheater 83.2 of the second separation unit 3.2 for superheating the carbohydrate-water mixture 4.

The recycling heat is transferred in particular to the third waste stream 37.3, here a vapor, which removes the water separated from the carbohydrate-water mixture 4 in the third separation unit 3.3, and/or—depending on the heat requirement or specific design—the fourth waste stream 37.4, also a vapor, withdrawn, at least one of the mass flows 37.3, 37.4 being supplied at least partially directly to the first working medium heat exchanger 25 of the compression heat pump 17. In the first working medium heat exchanger 25, the corresponding vapor is condensed to form a product condensate 69, which is finally discharged—in particular for further use as a heat source in other processes.

In each of the separation units 3, a vapor is produced by separating the water from the carbohydrate-water mixture 4. Since the fourth separation unit 3.4 is preferably not integrated into the heat flow of the other three separation units 3, it is not considered in the variable system explained above. According to this, x = 3, y = 3 and n = 3, so the recycling steam is denoted by B _xy = B ₀ , the first vapor from the first separation unit 3.1 by B ₁ , the second vapor from the second separation unit 3.2 by B ₂ , and the third vapor from the third separation unit 3.3 with B ₃ . The separation units 3 following the first separation unit 3.1--in particular their respective overheating devices 81--are each heated by the vapor from the immediately preceding separation unit 3, which brings in the respective useful heat. A condensate is produced in each of the separation units 3 in the overheating device 81, the condensates being referred to as K ₀ , K ₁ and K ₂ , analogously to the designation of the vapors. In particular, the second and third condensate K ₁ and K ₂ are each simultaneously product condensates of the separation unit 3.1, 3.2 and Heating condensates of the immediately following separation unit 3.2, 3.3 with an index increased by 1. A third condensate K ₃ of the third vapor B ₃ is part of the product condensate 69.

A proportion of the third and fourth mass flows 37.3, 37.4 to be re-cooled is preferably fed to the cooling tower 73. This proportion can be adjusted in accordance with requirements via a valve device 75 in particular.

In the fifth exemplary embodiment shown here, the product flow of the carbohydrate-water mixture 4 is at least partially designed counter to the heat flow: the carbohydrate-water mixture 4 first flows into the fourth separation unit 3.4 and then successively passes through the third separation unit 3.3 in the specified order , the second separation unit 3.2 and finally the first separation unit 3.1, which then leaves it concentrated. In particular, this ensures that the carbohydrate-water mixture 4 remains sufficiently flowable when it is concentrated. A predetermined proportion of the concentrated carbohydrate-water mixture 4 emerging from the evaporation chambers 79 of the first to third separation units 3 is returned to the respective separation units 3 via the respective superheating device 81; the remaining portion is fed to the separation unit 3 following along the product stream.

In particular, the exemplary embodiment of the separation device 1 shown here is operated with the following parameters: The fourth separation unit 3.4 is supplied with 83 t/h stillage with a dry matter content of 15% as the carbohydrate-water mixture 4, with the evaporation process taking place in the four separation units 3 is conducted in such a way that a mass flow of 31 t/h of concentrated stillage with a dry substance content of 39% results from the first separation unit 3.1.

The fourth separation unit 3.4 is supplied with 39 t/h of boiler house heating steam 49 at a temperature level of 94° C. at 0.79 bar absolute. The fourth mass flow 37.4 occurs with a mass flow of 41.7 t/h at 46° C. and a pressure of 0.1 bar absolute. The third vapor B ₃ occurs with a mass flow of 3.7 t/h at a temperature level of 46 °C and a pressure of 0.1 bar absolute. The first working medium heat exchanger 25 is supplied with 3.8 t/h, in particular the third mass flow 37.3, and to a small extent of 0.1 t/h the fourth mass flow 37.4. The remaining 41.6 t/h of the fourth waste stream 37.4 are supplied to the cooling tower 73—in particular via the valve device 75.

6.2 t/h of recycling steam 59 at 102° C. and 1.1 bar absolute are fed to the first separation unit 3.1.

The power consumption of the working media compressor 29 is 1.4 MW.

Claims (12)

Process for separating water from a carbohydrate-water mixture (4), wherein - The carbohydrate-water mixture (4) is introduced into at least one separation unit (3), in which water is separated from the carbohydrate-water mixture (4), wherein - Useful heat is supplied to the at least one separation unit (3) on a high-temperature side (9) in order to thermally separate the water from the carbohydrate-water mixture (4), wherein - Thermal secondary energy is removed from the at least one separation unit (3) on a low-temperature side (13), wherein - On the low-temperature side (13) of the thermal secondary energy recycling heat is removed, and wherein - the recycling heat is fed back to the high-temperature side (9) at a temperature level of more than 100 °C at least as part of the useful heat by means of a compression heat pump (17) having a closed working medium circuit (19). procedure after claim 1 , wherein the carbohydrate-water mixture (4) is selected from a group consisting of: a sucrose-containing medium, in particular a sucrose-containing solution, in particular thin juice or thick juice for sucrose production, sucrose syrup, an isomaltulose-containing medium, in particular one isomaltulose-containing solution, a stillage from bio-alcohol production, an alcohol-water solution, in particular a bio-alcohol-water solution, a sugar-alcohol-water medium, a starch-containing medium, and moisture-containing crop pieces, in particular sugar beet pulp or chicory roots. Method according to one of the preceding claims, wherein a plurality of separation units (3) is used to separate the water from the carbohydrate-water mixture (4), the separation units (3) being thermally connected to one another and being arranged in series along a heat flow , wherein the recycling heat of the secondary thermal energy on the low-temperature side (13) of a downstream separation unit (3) of the plurality of separation units (3) taken and by means of the compression heat pump (17) of the high-temperature side (9) an upstream term separation unit (3) of the plurality of separation units (3), wherein the upstream separation unit (3) is arranged along the heat flow upstream of the downstream separation unit (3). procedure after claim 3 , wherein the recycling heat of the secondary thermal energy is taken from a last separation unit (3) of the plurality of separation units (3) along the heat flow and fed to the high-temperature side (9) of a first separation unit (3) of the plurality of separation units (3) along the heat flow. Method according to one of the preceding claims, wherein - The useful heat is supplied to the at least one separation unit (3) via a heating medium (34), or wherein - The useful heat is used to heat, in particular to overheat, the carbohydrate-water mixture (4) upstream of an evaporation space (79) of the at least one separation unit (3). Process according to one of the preceding claims, in which the recycling heat is withdrawn from a waste stream (37) removing the water separated from the carbohydrate-water mixture (4), preferably - The mass flow (37) is at least partially fed directly to a first working medium heat exchanger (25), in particular a working medium evaporator (27), of the compression heat pump (17), or wherein - The recycling heat from the mass flow (37) is fed to the first working medium heat exchanger (25), in particular the working medium evaporator (27), mediated via a first heat transport device. Method according to one of the preceding claims, wherein the recycling heat is fed to a heating mass flow which is fed to the at least one separation unit (3) on the high-temperature side (9) in order to thermally separate the water from the carbohydrate-water mixture (4), preferably - At least a partial heating mass flow of the heating mass flow is guided upstream of the separation unit (3) through a second working medium heat exchanger (31), in particular a working medium condenser (33), of the compression heat pump (17), or wherein - The recycling heat is supplied to the heating mass flow from the second working medium heat exchanger (31), in particular the working medium condenser (33), mediated via a second heat transport device (41). Method according to one of the preceding claims, wherein at least one evaporation unit and at least one crystallization unit are used as the at least one separation unit (3), wherein thermal secondary energy of the at least one evaporation unit is removed for recycling heat, which is recovered from the at least one evaporation unit by means of a first compression heat pump (17). is supplied, wherein thermal secondary energy of the at least one crystallization unit is removed recycling heat, which is fed back to the at least one crystallization unit by means of a second compression heat pump (17). procedure after claim 8 , wherein a carbohydrate-water mixture (4) from the at least one evaporation unit is supplied to the at least one crystallization unit, and/or wherein the at least one evaporation unit and the at least one crystallization unit, in particular the first compression heat pump (17) and the second compression heat pump (17 ), are operated thermally separated from each other. Method according to one of the preceding claims, wherein the compression heat pump (17) is driven electrically, in particular with electrical energy from regenerative sources. Method according to one of the preceding claims, wherein a plurality of separation units (3) are operated as the at least one separation unit (3), with a waste stream (37) being discharged from each separation unit (3) of the plurality of separation units (3), with at least one of the waste streams (37) is used as a heat source for a further process. Separation device (1) for separating water from a carbohydrate-water mixture (4) with at least one separation unit (3), wherein - the at least one separation unit (3) has a product inlet (5) for introducing the carbohydrate-water mixture (4 ) into the separation unit (3) and a product outlet (7) for discharging a partially dehydrated carbohydrate-water mixture (4), the separation unit (3) being set up to separate water from the carbohydrate-water mixture (4). , wherein - the at least one separation unit (3) has a useful heat input (11) on a high-temperature side (9) for supplying useful heat and on a low-temperature side (13) a secondary energy output (15) for dissipating secondary thermal energy, wherein - the separating device (1) has a compression heat pump (17) with a closed working medium circuit (19) and is set up to extract recycling heat from the thermal secondary energy discharged via the secondary energy outlet (15) and to transfer the recycling heat to the useful heat inlet (11 ) on the high-temperature side (9) at a temperature level greater than 100 °C.

Images