Sorbitol production system

Abstract

The utility model discloses a sorbitol production system which comprises a feeding tank, a pH adjusting unit, a discharging tank and a hydrogenation reaction kettle, the feeding tank, the pH adjusting unit, the discharging tank and the hydrogenation reaction kettle are connected through pipelines, a glucose solution enters the pH adjusting unit from the feeding tank to adjust the pH value, then enters the discharging tank and then enters the hydrogenation reaction kettle from the discharging tank, the pH adjusting unit comprises a pH adjusting production group, the pH adjusting production group comprises a plurality of anion exchange resin columns which are arranged in parallel, each anion exchange resin column of the pH adjusting production group is provided with a feed port and a discharge port, the feed port is connected with a feed tank through a pipeline, and the discharge port is connected with a discharge tank through a pipeline. The anion exchange resin column is adopted to adjust the pH value of the raw material glucose, and the pH value is increased under the mild ion exchange condition so as to adapt to the needs of the hydrogenation process, so that the increase of conductivity and the generation of fusel caused by the addition of other inorganic salt ions are avoided.

Description

Technical Field

[0001] The utility model belongs to the field of chemical synthesis equipment, in particular to a sorbitol production system. Background Art

[0002] Sorbitol is an important intermediate for synthesizing vitamin C. It is generally produced by catalytic hydrogenation of glucose. In industrial production, crystallized glucose is dissolved in water or starch saccharification liquid is directly used as raw material. At this time, the sugar concentration is generally 45% to 52%, and the pH value is between 4 and 6. The optimal pH value required by the hydrogenation catalyst is 7.5-8.0. Therefore, the pH value of the raw glucose needs to be adjusted to 7.5-8.0 before hydrogenation. The existing production process is to add raw glucose to the mixing tank, and then add a dilute solution of high-concentration NaOH solution or sodium bicarbonate solution to adjust the pH value of the raw glucose.

[0003] This process of directly adding alkaline solution will result in the production of more mannitol, maltitol and other fusel alcohols during the hydrogenation reaction in the subsequent process. At the same time, the introduction of inorganic salt ions will increase the conductivity of the material, reduce the product quality, and increase the load of ion exchange in the subsequent refining process. Utility Model Content

[0004] In order to reduce the load of the subsequent refining process of sorbitol production, a new sorbitol production system is provided, which does not use an alkaline solution to adjust the pH value of raw material glucose.

[0005] The sorbitol production system provided in this application adopts the following technical solution:

[0006] A sorbitol production system includes a feed tank, a pH adjustment unit, a discharge tank and a hydrogenation reactor, wherein the feed tank, the pH adjustment unit, the discharge tank and the hydrogenation reactor are connected by a pipeline, and a glucose solution enters the pH adjustment unit from the feed tank to adjust the pH value and then enters the discharge tank, and then from the discharge tank to the hydrogenation reactor, wherein the pH adjustment unit includes a pH adjustment production group, the pH adjustment production group includes a plurality of anion exchange resin columns arranged in parallel, and the anion exchange resin column of the pH adjustment production group is provided with a feed port and a discharge port, the feed port is connected to the feed tank through a pipeline, and the discharge port is connected to the discharge tank through a pipeline. The anion exchange resin column is used to adjust the pH value of the raw glucose, and the pH is increased by its mild ion exchange conditions to meet the needs of the hydrogenation process, thereby avoiding the increase in conductivity caused by the addition of other inorganic salt ions and the generation of fusel alcohols.

[0007] The pH adjustment unit also includes a resin backwash regeneration group, which includes an anion exchange resin column switched from the pH adjustment production group, and the resin backwash regeneration group is connected to the pure water tank and the regeneration agent tank through a pipeline. When the anion exchange resin column of the pH adjustment production group is saturated with adsorption, it is necessary to perform backwash regeneration and other processes on the resin column to restore its pH adjustment function, then the feed inlet and outlet valves on the ion exchange resin column are closed, and it is switched to the resin backwash regeneration group for water topping, backwashing, regeneration and elution. At the same time, the resin column that has restored the pH adjustment function is switched back to the pH adjustment production group to adjust the pH value of the glucose solution. The anion exchange resin column of the present application uses dilute alkali as a regeneration agent. The so-called switching is achieved by opening and closing the valve on the pipeline.

[0008] The resin backwash regeneration group is provided with an anion exchange resin column, which is respectively connected to the pure water tank and the regeneration agent tank through pipelines. The anion exchange resin column is subjected to water top sugar, backwash, regeneration and elution respectively.

[0009] The ion exchange resin columns of the pH adjustment production group and the resin backwash regeneration group of the pH adjustment unit form a valve array type continuous ion exchange system.

[0010] The resin backwash regeneration group includes a water top sugar zone, a backwash zone, a regeneration zone and a leaching zone.

[0011] The water top sugar area includes a plurality of anion exchange resin columns connected in series, a water inlet and a water outlet are arranged on the anion exchange resin columns, and a pure water pipeline is connected to the water inlet of the first anion exchange resin column in the water top sugar area. The water top sugar area uses pure water to wash the glucose solution in the anion exchange resin column.

[0012] The backwashing zone comprises an anion exchange resin column. The anion exchange resin column in the backwashing zone is provided with a backwashing water inlet at the bottom and a backwashing water outlet at the top.

[0013] The regeneration zone comprises a plurality of anion exchange resin columns connected in series. A regeneration agent inlet and a regeneration agent outlet are arranged on the anion exchange resin columns. The regeneration agent inlet of the first anion exchange resin column is connected to the regeneration agent tank through a regeneration agent pipeline.

[0014] The elution zone comprises a plurality of anion exchange resin columns connected in series, a water inlet and a water outlet are arranged on the anion exchange resin columns, and a pure water pipeline is connected to the water inlet of the first anion exchange resin column.

[0015] The water outlet of the first anion exchange resin column in the elution zone is connected to the backwash water inlet of the first anion exchange resin column in the backwash zone through a pipeline.

[0016] The water outlet of the last anion exchange resin column in the elution zone is connected to the regeneration agent pipeline of the first anion exchange resin column in the regeneration zone through a pipeline.

[0017] Two feed pumps are arranged in parallel on the pipeline connecting the feed tank and the pH adjustment unit; two discharge pumps are arranged in parallel on the pipeline connecting the discharge tank and the pH adjustment unit. One feed pump and one discharge pump are used as standby to avoid delaying production due to maintenance.

[0018] The present application uses multiple anion exchange resin columns arranged in parallel to adjust the pH of the raw glucose solution without adding alkali solution, thereby reducing the production of fusel alcohols in the hydrogenation process, avoiding the addition of other inorganic salt ions, and reducing the load of subsequent processes. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural diagram of Example 1 of the present application.

[0020] Figure 2 It is a structural diagram of Example 2 of the present application. DETAILED DESCRIPTION

[0021] The following is combined with Figure 1-2 This application is described in further detail. Example 1

[0022] like Figure 1 As shown, a sorbitol production system includes a feed tank 1, a pH adjustment unit 2, a discharge tank 3 and a hydrogenation reactor 4. The feed tank 1, the pH adjustment unit 2, the discharge tank 3 and the hydrogenation reactor 4 are connected by a pipeline. The glucose solution enters the pH adjustment unit 2 from the feed tank 1 to adjust the pH value and then enters the discharge tank 3, and then from the discharge tank 3 to the hydrogenation reactor 4.

[0023] The pipeline is provided with a feed pump 5, a flow meter 6, an automatic regulating valve 7, a remote pressure gauge 8 and a discharge pump 9.

[0024] Two feed pumps 5 are arranged in parallel on the pipeline connecting the feed tank 1 and the pH adjusting unit 2 ; two discharge pumps 9 are arranged in parallel on the pipeline connecting the discharge tank 3 and the pH adjusting unit 2 .

[0025] The pH adjustment unit 2 includes a pH adjustment production group 201 and a resin backwash regeneration group 202. The pH adjustment production group 201 includes a plurality of anion exchange resin columns arranged in parallel. These anion exchange resin columns are provided with a feed port and a discharge port. The feed port is connected to the feed tank 1 through a pipeline, and the discharge port is connected to the discharge tank 3 through a pipeline. The feed port is arranged at the top of the anion exchange resin column, and the discharge port is arranged at the bottom of the anion exchange resin column; the resin backwash regeneration group 202 includes an anion exchange resin column switched from the pH adjustment production group 201; the anion exchange resin columns of the resin backwash regeneration group 202 are respectively connected to the pure water tank 10 and the regeneration agent tank 11 through pipelines, and automatic regulating valves are arranged on the pipelines. The anion exchange resin columns of the resin backwash regeneration group 202 are respectively subjected to water topping, backwashing, regeneration and elution by pure water and regeneration agent (the four steps are not performed simultaneously), and the corresponding automatic regulating valves are respectively opened during water topping, backwashing, regeneration and elution.

[0026] The sorbitol solution generated by the catalytic reaction of the raw glucose solution in the hydrogenation reactor 4 needs to be decolorized by a granular carbon column, purified by desalination and concentrated by evaporation to obtain a liquid sorbitol product. Example 2

[0027] like Figure 2 As shown, a sorbitol production system includes a feed tank 1, a pH adjustment unit 2, a discharge tank 3 and a hydrogenation reactor 4. The feed tank 1, the pH adjustment unit 2, the discharge tank 3 and the hydrogenation reactor 4 are connected by a pipeline. The glucose solution enters the pH adjustment unit 2 from the feed tank 1 to adjust the pH value and then enters the discharge tank 3, and then from the discharge tank 3 to the hydrogenation reactor 4.

[0028] The pipeline is provided with a feed pump 5, a flow meter 6, an automatic regulating valve 7, a remote pressure gauge 8 and a discharge pump 9.

[0029] Two feed pumps 5 are arranged in parallel on the pipeline connecting the feed tank 1 and the pH adjusting unit 2 ; two discharge pumps 9 are arranged in parallel on the pipeline connecting the discharge tank 3 and the pH adjusting unit 2 .

[0030] The pH adjustment unit 2 includes a pH adjustment production group 201 and a resin backwash regeneration group 202. The pH adjustment production group 201 includes a plurality of anion exchange resin columns arranged in parallel. These anion exchange resin columns are provided with a feed port and a discharge port. The feed port is connected to the feed tank 1 through a pipeline, and the discharge port is connected to the discharge tank 3 through a pipeline. The feed port is arranged at the top of the anion exchange resin column, and the discharge port is arranged at the bottom of the anion exchange resin column. In this embodiment, the pH adjustment production group 201 includes three anion exchange resin columns arranged in parallel, namely Figure 2 1#-3# resin columns.

[0031] The resin backwash regeneration group 202 includes an anion exchange resin column switched from the pH adjustment production group 201 , and is specifically divided into a water top sugar zone 2021 , a backwash zone 2022 , a regeneration zone 2023 and a leaching zone 2024 .

[0032] The water top sugar area 2021 includes a plurality of anion exchange resin columns connected in series, and a water inlet and a water outlet are arranged on the anion exchange resin column. The pure water tank 10 is connected to the water inlet of the first anion exchange resin column in the water top sugar area through a pure water pipeline. In this embodiment, the water top sugar area 2021 has three anion exchange resin columns, and the water inlet at the top of the first resin column is connected to the pure water tank 10 through a pure water pipeline. The two resin columns behind are connected in series in a top-in and bottom-out manner to clean the glucose solution in the column. The bottom water outlet of the last resin column discharges the liquid to the sweet water tank 12 for the sugaring process and repeated use.

[0033] The backwash zone 2022 includes an anion exchange resin column, and the anion exchange resin column in the backwash zone is provided with a backwash water inlet at the bottom and a backwash water outlet at the top. In this embodiment, the backwash zone 2022 has an anion exchange resin column, which adopts a bottom-in-top-out method, and the backwash water outlet at the top is connected to a sewage treatment station for sewage discharge.

[0034] The backwash water inlet of the anion exchange resin column in the backwash area 2022 can be connected to the water outlet of the first anion exchange resin column in the leaching area, so as to make full use of water resources.

[0035] The regeneration zone 2023 includes a plurality of anion exchange resin columns connected in series, and a regeneration agent inlet and a regeneration agent outlet are provided on the anion exchange resin columns. The regeneration agent inlet of the first anion exchange resin column is connected to the regeneration agent tank 11 through a regeneration agent pipeline. In this embodiment, the regeneration zone 2023 has three anion exchange resin columns, and the resin in the ion exchange resin column is regenerated using a 4% dilute alkali solution. The three anion exchange resin columns are regenerated in series, and the regeneration agent inlet at the top of the first resin column is connected to the regeneration agent tank 11 through a pipeline, and the regeneration agent outlet at the bottom of the first resin column is connected to the regeneration agent inlet at the top of the second resin column, and the regeneration agent outlet at the bottom of the second resin column is connected to the regeneration agent inlet at the top of the third resin column. The regeneration agent outlet at the bottom of the third resin column is connected to the sewage treatment station through a discharge pipeline and discharges sewage.

[0036] The elution zone 2024 includes a plurality of anion exchange resin columns connected in series, and a water inlet and a water outlet are arranged on the anion exchange resin column, and the pure water tank 10 is connected to the water inlet of the first anion exchange resin column through a pure water pipeline. In this embodiment, the elution zone 2024 includes two anion exchange resin columns switched from the regeneration zone 2023, and pure water is used to elute the resin in the anion exchange resin column. Since there is still some regeneration agent that has not been fully utilized in the column, the outlet pipe of the elution zone is connected to the inlet pipe of the regeneration zone 2023. The inlet pipe of the elution zone is connected to the pure water pipe, and two ion exchange columns are connected in series. The lower discharge of the first column is connected to the upper feed port of the second ion exchange column, and the lower discharge of the second column is connected to the pipe of the regeneration zone. The elution liquid is used in the regeneration zone, so the elution liquid can be fully utilized.

[0037] The anion exchange resin column uses a macroporous strong base styrene anion exchange resin.

[0038] The pH adjustment unit 2 is configured as a valve array continuous ion exchange resin column system, which can realize continuous pH adjustment. After the ion exchange resin column in the pH adjustment production group is saturated, it is switched out and enters the water top sugar area. After cleaning, it is switched to the backwash area, regeneration area, and elution area. The valve is opened and closed to switch in sequence, so that the number of ion exchange resin columns in each working area remains unchanged, and the pH adjustment can be performed continuously and stably.

[0039] The sorbitol solution generated by the catalytic reaction of the raw glucose solution in the hydrogenation reactor 4 needs to be decolorized by a granular carbon column, purified by desalination and concentrated by evaporation to obtain a liquid sorbitol product. Example 3

[0040] A comparative study was conducted on the production of sorbitol using a sorbitol production system having a pH adjustment unit according to Example 2 and a system (comparative example) in which a dilute alkali solution or a sodium bicarbonate solution was added to adjust the pH.

[0041] Table 1 Comparison of glucose performance after pH adjustment

[0042]

[0043] Table 2 Comparison of properties of crude sorbitol obtained after hydrogenation

[0044]

[0045] It can be seen from Tables 1 and 2 above that pH adjustment through anion exchange resin columns can reduce the conductivity and color value of glucose, reduce the production of subsequent hydrogenated fusel alcohols, and also reduce the load of the sorbitol refining process.

[0046] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A sorbitol production system, comprising a feed tank, a pH adjustment unit, a discharge tank and a hydrogenation reactor, wherein the feed tank, the pH adjustment unit, the discharge tank and the hydrogenation reactor are connected by a pipeline, and a glucose solution enters the discharge tank from the feed tank after the pH value is adjusted in the pH adjustment unit, and then enters the discharge tank from the discharge tank to the hydrogenation reactor, characterized in that: The pH adjustment unit includes a pH adjustment production group, which includes multiple anion exchange resin columns arranged in parallel. The anion exchange resin columns of the pH adjustment production group are provided with a feed port and a discharge port. The feed port is connected to the feed tank through a pipeline, and the discharge port is connected to the discharge tank through a pipeline.

2. The sorbitol production system according to claim 1, characterized in that: The pH adjustment unit also includes a resin backwash regeneration group, which includes an anion exchange resin column switched from the pH adjustment production group. The resin backwash regeneration group is connected to the pure water tank and the regeneration agent tank through pipelines.

3. The sorbitol production system according to claim 2, characterized in that: The resin backwash regeneration group is provided with an anion exchange resin column, which is respectively connected to the pure water tank and the regeneration agent tank through pipelines.

4. The sorbitol production system according to claim 2, characterized in that: The resin backwash regeneration group includes a water top sugar zone, a backwash zone, a regeneration zone and a leaching zone.

5. The sorbitol production system according to claim 4, characterized in that: The water top sugar zone includes a plurality of anion exchange resin columns connected in series, on which water inlets and water outlets are arranged, and a pure water pipeline is connected to the water inlet of the first anion exchange resin column in the water top sugar zone.

6. The sorbitol production system according to claim 4, characterized in that: The backwashing zone comprises an anion exchange resin column. The anion exchange resin column in the backwashing zone is provided with a backwashing water inlet at the bottom and a backwashing water outlet at the top.

7. The sorbitol production system according to claim 4, characterized in that: The regeneration zone comprises a plurality of anion exchange resin columns connected in series. A regeneration agent inlet and a regeneration agent outlet are arranged on the anion exchange resin columns. The regeneration agent inlet of the first anion exchange resin column is connected to the regeneration agent tank through a regeneration agent pipeline.

8. The sorbitol production system according to claim 4, characterized in that: The elution zone comprises a plurality of anion exchange resin columns connected in series, a water inlet and a water outlet are arranged on the anion exchange resin columns, and a pure water pipeline is connected to the water inlet of the first anion exchange resin column.

9. The sorbitol production system according to claim 8, characterized in that: The water outlet of the first anion exchange resin column in the elution zone is connected to the backwash water inlet of the first anion exchange resin column in the backwash zone through a pipeline.

10. The sorbitol production system according to claim 8, characterized in that: The water outlet of the last anion exchange resin column in the elution zone is connected to the regeneration agent pipeline of the first anion exchange resin column in the regeneration zone through a pipeline.

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