PROCESS FOR PRODUCING THIN JUICE FOR THE PRODUCTION OF SUGAR, PROCESS FOR PRODUCING SUGAR AND SUGAR PRODUCTION PLANT

Abstract

The present invention relates to a process for producing thin juice (17, 27) for the production of sugar, wherein lime milkin a first liming step (3)is first added to a raw juice (14) to obtain a mixture of raw juice and lime milk (15), and then carbon dioxidein a first carbonation step (4)is added to the mixture of raw juice and lime milk (15) to obtain a mixture of raw juice and precipitated non-sugar substances (16), and the mixture of raw juice and precipitated non-sugar substances (16) is thenin a first filtration step (5)filtered to obtain a first thin juice (17), lime milkin a second liming step (3)is optionally added to the first thin juice (17) to obtain a mixture of first thin juice and lime milk (25), and carbon dioxidein a second carbonation step (4)add carbon dioxide to the first thin juice (17) or the mixture of first thin juice and lime milk (25) to obtain a mixture of first thin juice and precipitated non-sugar substances (26), andin a second filtration step (5)filter the mixture of first thin juice and precipitated non-sugar substances (26) to obtain a second thin juice (27), wherein at least one first sensor device (21) is used to detect first measurement data relating to the mixture of raw juice and lime milk (15) and/or the mixture of first thin juice and lime milk (25) during or after the first or second liming step (3, 3), and/or at least one second sensor device (22) is used to detect second measurement data relating to the mixture of raw juice and precipitated non-sugar substances (16) and/or the mixture of first thin juice and precipitated non-sugar substances (26) during or after the first or second carbonation step (4, 4), and/or
at least one third sensor device (23) is used to detect third measurement data relating to the first and/or second thin juice (17).

Claims

1. A process for producing thin juice for the production of sugar, wherein lime milk, in a first liming step, is first added to a raw juice to obtain a mixture of raw juice and lime milk, and carbon dioxide, in first carbonation step, is then added to the mixture of raw juice and lime milk to obtain a mixture of raw juice and precipitated non-sugar substances, and then, in a first filtration step, the mixture of raw juice and precipitated non-sugar substances is filtered to obtain a first thin juice, optionally, in a second liming step, lime milk is added to the first thin juice to obtain a mixture of first thin juice and lime milk, and optionally, in a second carbonation step, carbon dioxide is added to the first thin juice or the mixture of first thin juice and lime milk to obtain a mixture of first thin juice and precipitated non-sugar substances, and in a second filtration step, the mixture of first thin juice and precipitated non-sugar substances is filtered to obtain a second thin juice, characterized in that at least one first sensor device used to detect first measurement data relating to the mixture of raw juice and lime milk and/or the mixture of first thin juice and lime milk during or after the first or second liming step, and/or at least one second sensor device is used to detect second measurement data relating to the mixture of raw juice and precipitated non-sugar substances and/or the mixture of first thin juice and precipitated non-sugar substances during or after the first or second carbonation step, and/or at least one third sensor device is used to detect third measurement data relating to the first and/or second thin juice.

2. (canceled)

3. The process according to claim 1, characterized in that: at least one process parameter of the first and/or second liming step is set depending on the first measurement data and/or the second measurement data and/or the third measurement data; wherein the process parameter is an added amount of lime milk and/or a target value of the pH value and/or a concentration of the lime milk and/or an added amount of precipitated calcium carbonate and/or a withdrawal amount of carbonated juice.

4. The process according to claim 1, characterized in that: at least one process parameter of the first and/or second carbonation step is set depending on the first measurement data and/or the second measurement data and/or the third measurement data; and.or at least one process parameters of the first and/or second filtration step is set depending on the first measurement and/or the second measurement data and/or the third measurement data; at least one process parameter of the first and/or second liming step is set depending on the first measurement data and/or the second measurement data and/or the third measurement data; and/or wherein the first, second, and/or third measurement data comprises a content indication of the pectins and/or dextrans, wherein an added amount of dextranase is determined based on the content indication of the pectins and/or dextrans.

5. (canceled)

6. The process according to claim 1, characterized in that the first sensor device has a first optical imaging device and the first measurement data comprises first image data, and/or the second sensor device has a second optical imaging device and the second measurement data comprises second image data, and/or the third sensor device has a third optical imaging device and the third measurement data comprises third image data.

7. The process according to claim 6, characterized in that a geometric property of the particles and/or air inclusions contained in the respective raw juice or thin juice is/are determined based on the first, second, and/or third image data.

8. The process according to claim 7, characterized in that the geometric property is a flake shape, optionally wherein a color of a liquid phase of the respective raw juice or thin juice is determined based on the first, second, and/or third image data.

9. (canceled)

10. The process according to claim 8, characterized in that, in the first and/or second liming step, an added amount of lime milk is set depending on the identified flake shape of the particles and/or the color of the liquid phase.

11. The process according to claim 8, characterized in that an added amount of dextranase is set depending on the determined flake shape of the particles and/or the determined color of the liquid phase.

12. The process according to claim 1, characterized in that the first sensor device has a first near-infrared spectroscopy device and the first measurement data comprises a first content indication of an ingredient, and/or the second sensor device has a second near-infrared spectroscopy device and the second measurement data comprises a second content indication of an ingredient, and/or the third sensor device has a third near-infrared spectroscopy device and the third measurement data comprises a third content indication of an ingredient.

13. The process of claim 1, wherein the first, second, and/or third measurement data comprise a content indication of the pectins and/or dextrans, wherein a status indication of a status of one or more filter devices, for example filter candles, is determined on the basis of the content indication of the pectins and/or dextrans used in the filtration step.

14. (canceled)

15. The process of claim 1, wherein the first sensor device has a first nitrogen sensor and the first measurement data comprises a first nitrogen concentration, and/or the second sensor device has a second nitrogen sensor and the second measurement data comprises a second nitrogen concentration, and/or the third sensor device has a third nitrogen sensor and the third measurement data comprises a third nitrogen concentration.

16. The process of claim 1, wherein the third sensor device has a turbidity and/or color sensor and the third measurement data comprises a turbidity and/or color indication.

17. The process according to claim 16, characterized in that a process parameter of the first and/or second filtration step is set depending on the turbidity and/or color indication.

18. The process of claim 1, wherein the third sensor device has a Brix sensor and the third measurement data comprises a sugar content.

19. The process of claim 1, wherein the first sensor device is arranged in a first bypass line, into which the mixture of raw juice and lime milk or the mixture of first thin juice and lime milk is introduced during or after the first or second liming step, and a standing mixture is generated to detect the first measurement data, and/or the second sensor device is arranged in a second bypass line, into which the mixture of raw juice and precipitated non-sugar substances or the mixture of first thin juice and precipitated non-sugar substances is introduced during or after the first or second carbonation step, and a standing mixture is generated for detecting the second measurement data, and/or the third sensor device is arranged in a third bypass line, into which the first or second thin juice is introduced and a standing thin juice is generated to detect the third measurement data.

20. The process according to claim 19, characterized in that, after carrying out a measurement in the first, second and/or third bypass line, a self-cleaning procedure for cleaning the bypass line is carried out.

21. The process according to claim 1, characterized in that: a particle size of particles is determined based on the first measurement data, in particular first image data, and/or the second measurement data, in particular second image data, and/or the third measurement data, in particular third image data; or a rate of descent of particles is determined based on the first measurement data, in particular first image data, and/or the second measurement data, in particular second image data, and/or the third measurement data, in particular third image data.

22. (canceled)

23. The process according to claim 1, characterized in that acrystal habit of calcium carbonate is determined based on the first measurement data, in particular first image data, and/or the second measurement data, in particular second image data, and/or the third measurement data, in particular third image data.

24. A process for producing sugar, wherein thin juice is produced according to a process according to claim 1, and sugar is produced from the thin juice in subsequent process steps: optionally, wherein at least one process parameter of any one of the subsequent process steps is set depending on the first measurement data and/or the second measurement data and/or third measurement data, wherein the subsequent process step is a thickening step or a crystallization step or a separation step; optionally, wherein to obtain the raw juice, an extraction step is carried out to obtain the raw juice from sugar beet pulp, wherein at least one process parameter of the extraction step is set depending on the first measurement data and/or the second measurement data and/or the third measurement data.

25. (canceled)

26. (canceled)

27. A sugar production plant with a juice purification facility, which is configured to: First, in a first liming step, add lime milk is first added to a raw juice (14) to obtain a mixture of raw juice and lime milk, and Then, in a first carbonation step, add carbon dioxide to the mixture of raw juice and lime milk to obtain a mixture of raw juice and precipitated non-sugar substances, and Then, in a first filtration step, filter the mixture of raw juice and precipitated non-sugar substances to obtain a first thin juice, Optionally, in a second liming step, add lime milk to the first thin juice to obtain a mixture of first thin juice and lime milk, and Optionally, in a second carbonation step, add carbon dioxide to the first thin juice or the mixture of first thin juice and lime milk to obtain a mixture of first thin juice and precipitated non-sugar substances, and, in a second filtration step, filter the mixture of first thin juice and precipitated non-sugar substances to obtain a second thin juice, characterized by: at least one first sensor device for detecting first measurement data relating to the mixture of raw juice and lime milk and/or the mixture of first thin juice and lime milk during or after the first or second liming step, and/or at least one second sensor device for detecting second measurement data relating to the mixture of raw juice and precipitated non-sugar substances and/or the mixture of first thin juice and precipitated non-sugar substances during or after the first or second carbonation step, and/or at least a third sensor device for detecting third measurement data relating to the first and/or second thin juice.

Description

BRIEF DESCRIPTION OF THE FIGURES

[0069] FIG. 1 shows a process for producing sugar according to a first exemplary embodiment of the invention.

[0070] FIG. 2 shows a process for producing thin juice according to a first exemplary embodiment of the invention.

[0071] FIG. 3 shows a process for producing sugar according to a second exemplary embodiment of the invention.

[0072] FIG. 4 shows a process for producing thin juice according to a second exemplary embodiment of the invention.

EMBODIMENTS OF THE INVENTION

[0073] In the various figures, the same parts are always provided with the same reference numerals and are therefore usually only named or mentioned once.

[0074] The flow chart shown in FIG. 1 shows a first exemplary embodiment of a process according to the invention for producing sugar, which is carried out in a sugar production plant. In the exemplary embodiment, sugar beets are used as the starting material. The sugar beets delivered to the sugar production plant are preferably first cleaned, that is, freed from buildup such as soil, sand, or leaves. In a first process step of cutting 1, the sugar beets are crushed by a cutting machine obtain sugar beet pulp 11.

[0075] The sugar beet pulp 11 is leached by water in an extraction device in an extraction process step 2 or juice extraction step following cutting 1. Optionally, the sugar beet pulp 11 can first be preheated, for example in a range from 60? C. to 80? C., to make the cell walls more permeable. The actual extraction 2 takes place in a countercurrent process in which the sugar beet pulp 11 is conveyed or passed through the extraction device in a countercurrent to hot water. The product of extraction 2, in addition to sugar beet pulp residue, is raw juice 14, which contains almost all of the sugar contained in the sugar beets.

[0076] According to a modification of the exemplary embodiment, sugar cane can be used as the starting material. The sugar cane is first cut and can then also be fed to an extraction step 2 to extract raw juice 14 using a diffusion process. Alternatively, the raw juice can be obtained by press extractioni.e. by pressing the sugar cane or sugar cane chips.

[0077] Lime in the form of lime milk is added to the raw juice 14 in a liming process step 3. The lime binds non-sugar substances contained in the raw juice 14. Acids are neutralized and the pH value is raised.

[0078] In the subsequent process step of carbonation 4, carbon dioxide is introduced into the mixture 15 of raw juice and lime milk. Calcium and other non-sugar substances are bound and precipitate as lime (calcium carbonate). In the subsequent process step of filtration 5, the lime is then separated off and the thin juice 17 remains. The process steps of liming 3, carbonation 4 and filtration 5 are also referred to as juice purification. The steps of liming 3, carbonation 4, and filtration 5 can optionally be carried out in this order multiple times, for example twice in a row, to improve the cleaning result, see FIG. 3.

[0079] This is followed by the process step of thickening 6, in which the thin juice 17 is thickened in a usually multi-stage heating process to obtain the thick juice 18.

[0080] Sugar is crystallized from the thick juice 18 in a crystallization process step 7 at high temperature and negative pressure. The crystallization 7 preferably comprises multiple successive crystallization steps. A mixture 19 of thick juice and granulated sugar is obtained, which is also known as magma.

[0081] Finally, the crystal sugar is separated in a separation process step 8, for example in a centrifuge.

[0082] In the process according to FIG. 1, juice purification according to the invention with the process steps liming 3, carbonation 4, and filtration 5 is used, which will be explained below using the illustration in FIG. 2.

[0083] During juice purification, lime milk is first added to the raw juice 14 in the liming step 3 to obtain a mixture 15 of raw juice and lime milk. During the liming step 3, first measurement data relating to the mixture of raw juice and lime milk are detected with a first sensor device 21 during the liming step. For example, the liming step 3 can include a sub-step of pre-liming, and the first sensor device 21 can detect first measurement data relating to the raw juice after pre-liming. In such a configuration, the end point of the pre-liming can be determined by evaluating the measurement data detected with the first sensor device 21. The pre-liming sub-step can be followed by a main liming sub-step. A second main liming step can optionally be intended. Alternatively, the first sensor device 21 can be arranged after the liming step 3, so that measurement data relating to the mixture 15 of raw juice and lime milk are detected.

[0084] Carbon dioxide is then added to the mixture 15 of raw juice and lime milk in the carbonation step 4. This causes non-sugar substances to precipitate. The resulting mixture 16 of raw juice and precipitated non-sugar substances is detected by a second sensor device 22 to obtain second measurement data relating to the mixture of raw juice and precipitated non-sugar substances after the carbonation step. Alternatively, the second sensor device 22 can be arranged such that measurement data is detected during the carbonation step 4.

[0085] The mixture 16 of raw juice and precipitated non-sugar substances is then filtered in the filtration step 5 to obtain the thin juice 17. Third measurement data relating to the thin juice 17 is detected with a third sensor device 23.

[0086] In the exemplary embodiment, the first sensor device 21 comprises an optical imaging device which detects first image data. The optical imaging device can be designed, for example, as a camera, in particular as a color camera. The optical imaging device of the first sensor device 21 is used to determine first image data, on the basis of which a particle size of particles/flakes contained in the raw juice is determined. Alternatively or additionally, a rate of descent of the particles is determined. Alternatively or additionally, a flake shape and/or a color of the particles is determined. Alternatively or additionally, the crystal habitus of calcium carbonate contained in the raw juice is determined. A process parameter of the liming step is set depending on the specific valuesthat is, the particle size and/or the rate of descent and/or the crystal habit. For example, the added amount of lime milk and/or a target value of the pH value and/or a concentration of the lime milk and/or an added amount of precipitated calcium carbonate can be set depending on the specific values. The added amount of lime milk and/or an added amount of dextranase is preferably adjusted depending on the flake shape and/or color of the particles determined.

[0087] The second sensor device 22 according to the exemplary embodiment comprises an optical imaging device which detects second image data and a near-infrared spectroscopy device which determines content indication on ingredients of the mixture 16 of raw juice and precipitated non-sugar substances. These are the following ingredients and their content: sucrose, fructose, glucose, lactic acid, oxalic acid, oxalates, nitrates, nitrites, pectins, dextrans, nitrogen. Depending on the determined dextran content, the added amount of dextranase added during juice purification is controlled. Furthermore, the extraction time and/or extraction temperature is set in extraction step 2 depending on the determined glucose content. Depending on the determined glucose content, an evaporation temperature during thickening 6 of the thin juice 17 and/or a dwell time during thickening 6 of the thin juice 17 and/or a number of crystallization steps during crystallization 7 of the thick juice 18 are also set.

[0088] In addition, a status indication regarding a condition of the filter devices used for filtering 5, for example filter candles, can be determined based on the content of pectins and/or dextrans determined as well as on the image data from the optical imaging device of the second sensor device 22.

[0089] The third sensor device 23 has a near-infrared spectroscopy device that determines content indication on the ingredients of the thin juice 17, as well as a turbidity and/or color sensor and a Brix sensor. The measurement data detected with the third sensor device 23 enables quality control of the juice purification processes 3, 4, 5.

[0090] The flow chart shown in FIG. 3 shows a second exemplary embodiment of a process according to the invention for producing sugar, which is carried out in a sugar production plant. The procedure according to the second exemplary embodiment corresponds to the first exemplary embodiment as described in FIG. 1, except that a two-stage juice purification 3, 4, 5, 3, 4, 5 is carried out. In a second liming step 3, lime milk is added to the first thin juice 17 to obtain a mixture of first thin juice and lime milk 25. Carbon dioxide and preferably soda or caustic soda are then added to this mixture of first thin juice and lime milk 25 in a second carbonation step 4 to obtain a mixture of first thin juice and precipitated non-sugar substances 26. This mixture of first thin juice and precipitated non-sugars 26 is then filtered in a second filtration step 5, so that a second thin juice 27 is obtained. The second filtration step 5 is preferably multi-stage, e.g. two-stage.

[0091] The two-stage juice purification according to FIG. 3 is explained in more detail below using the illustration in FIG. 4.

[0092] In contrast to the juice purification according to the first exemplary embodiment, the juice purification of the second exemplary embodiment provides for another first sensor device 21 which, during the second liming step 3 detects other first measurement data relating to the mixture of the first thin juice and lime milk. The other first sensor device 21 comprises an optical imaging device, which detects further first image data. The optical imaging device can be designed, for example, as a camera, in particular as a color camera. The optical imaging device of the first sensor device 21 is used to determine first image data, on the basis of which a particle size of particles contained in the raw juice is determined. Alternatively or additionally, a rate of descent of the particles is determined. Alternatively or additionally, the crystal habitus of calcium carbonate contained in the raw juice is determined. A process parameter of the second carbonation step 3 is set depending on the specific valuesthat is, the particle size and/or the rate of descent and/or the crystal habit. For example, the added amount of lime milk and/or a target value of the pH value and/or a concentration of the lime milk and/or an added amount of precipitated calcium carbonate can be adjusted depending on the specific values.

[0093] In addition, the obtained mixture 26 of first thin juice and precipitated non-sugars is detected by a second sensor device 22 to obtain further second measurement data concerning mixture 26 of first thin juice and precipitated non-sugars after the carbonation step. Alternatively, the other second sensor device 22 can be arranged such that measurement data is detected during the carbonation step 4. The second sensor device 22 according to the second exemplary embodiment comprises an optical imaging device which detects second image data and a near-infrared spectroscopy device which determines content indication on ingredients of the mixture 26 of raw juice and precipitated non-sugar substances. These are the following ingredients and their content: sucrose, fructose, glucose, lactic acid, oxalic acid, oxalates, nitrates, nitrites, pectins, dextrans, nitrogen. Depending on the determined dextran content, the added amount of dextranase added during juice purification is controlled. Furthermore, the extraction time and/or extraction temperature is set in extraction step 2 depending on the determined glucose content. Depending on the determined glucose content, an evaporation temperature during thickening 6 of the thin juice 27 and/or a dwell time during thickening 6 of the thin juice 27 and/or a number of crystallization steps during crystallization 7 of the thick juice 18 are also set. In addition, a status indication regarding a condition of the filter devices used for filtering 5, for example filter candles, can be determined based on the content of pectins and/or dextrans determined as well as on the image data from the optical imaging device of the other second sensor device 22.

[0094] A third sensor 23 is used to detect further third measurement data concerning the second thin juice 27. The third sensor 23 has a near-infrared spectroscopic device that determines the content of ingredients of the second thin juice 27, a turbidity and/or colour sensor and a Brix sensor. The measurement data detected with the third sensor device 23 enables quality control of the juice purification processes 3, 4, 5, 3, 4, 5.

[0095] A particularly preferred modification of the second exemplary embodiment comprises

[0096] exactly one first sensor device 21 for detecting first measurement data relating to the mixture of raw juice and lime milk 15 during or after the first liming step 3, and

[0097] exactly one second sensor facility 22 for detecting second measurement data relating to the mixture of first thin juice and precipitated non-sugar substances 26 during or after the second carbonation step 4; and

[0098] exactly one third sensor 23 for detecting third measurement data relating to the second thin juice 27.

[0099] The processes and systems described above with the sensor devices 21, 22, 23 enable the analysis and/or control of juice purification and/or other devices or process steps in the sugar production process with low latency.

LIST OF REFERENCE NUMERALS

[0100] 1 Cutting process step [0101] 2 Extraction process step [0102] 3 Calculation process step [0103] 4 Carbonation process step (2 stages) [0104] 5 Filtration process step [0105] 6 Thickening process step [0106] 7 Crystallization process step [0107] 8 Separation process step [0108] 10 cutting machine [0109] 11 sugar beet pulp [0110] 12 water [0111] 13 leftover sugar beet pulp [0112] 14 raw juice [0113] 15 mixture of raw juice and lime milk [0114] 16 mixture of raw juice and precipitated non-sugar substances [0115] 17 thin juice [0116] 18 thick juice [0117] 19 mixture of thick juice and granulated sugar [0118] 21 sensor device [0119] 22 sensor device [0120] 23 sensor device