Device for refining sorbitol by hydrogenation of crystalline sugar mother liquor

Abstract

The utility model discloses a device for refining sorbitol by hydrogenating crystalline sugar mother liquor, which is characterized in that a mother liquor buffer tank is connected with a pre-hydrogenation buffer tank through a mother liquor delivery pump, the pre-hydrogenation buffer tank is connected with a tube pass inlet of a hot water preheater through a pre-hydrogenation delivery pump, and a tube pass outlet of the hot water preheater is connected with a high-pressure buffer tank through a steam heater; an outlet of the high-pressure buffer tank is connected with a feed port of the catalytic reaction kettle through a high-pressure delivery pump, a sorbitol outlet of the catalytic reaction kettle is connected with a medium inlet of the hot water heat exchanger, a medium outlet of the hot water heat exchanger is connected with a feed port of the settling tank, and a bottom outlet of the settling tank is connected with the pre-hydrogenation buffer tank through a catalyst delivery pump; a hot water outlet of the hot water heat exchanger is connected with a shell pass inlet of the hot water preheater, a shell pass outlet of the hot water preheater is connected with the hot water circulating tank, and an outlet of the hot water circulating tank is connected with a hot water inlet of the hot water heat exchanger through the hot water circulating pump. The sorbitol syrup refined by the device is good in quality, low in energy consumption and less in side reaction.

Description

Technical Field

[0001] The utility model relates to a rice syrup deep processing system, in particular to a device for hydrogenating and refining sorbitol through crystallized sugar mother liquid, belonging to the technical field of rice syrup processing equipment. Background Art

[0002] In the process of deep processing of rice starch to produce crystalline sugar, the rice slurry must first be liquefied, and then the syrup and protein are separated. The separated syrup is refined and cooled to crystallize to obtain crystalline sugar. In order to ensure the product quality of the crystalline sugar and achieve the required DX value of the product, part of the crystalline sugar mother liquor produced in the separation process of normal crystalline sugar is refluxed, and part of it needs to be sold as a by-product.

[0003] In order to increase the added value, the crystallized sugar mother liquor produced by crystallization separation can be refined by hydrogenation to obtain daily chemical grade sorbitol, thereby increasing the factory's profits. The traditional process has the following defects:

[0004] 1. The mother liquor needs to be heated to 140°C during the hydrogenation process, which not only makes the hydrogenation reaction energy-intensive but also makes side reactions more likely to occur;

[0005] 2. After hydrogenation, the crystallized sugar mother liquor needs to be refined by ion exchange. The conventional ion exchange process is a strong acid and weak base mixed bed production process. Because the cationic resin is a strong acid resin, although most of the catalysts have been recovered in the previous process, there are still very few catalysts remaining in the sorbitol syrup. In the process of ion exchange resin removal, it is found that after the strong acid resin adsorbs the catalyst, the catalyst is difficult to be washed out, resulting in nickel poisoning of the catalyst, resulting in a decrease in the exchange capacity of the cationic resin. It is necessary to optimize the production process to improve the exchange capacity of the ion exchange resin and the product quality of sorbitol.

[0006] The Chinese invention patent with announcement number CN109305882B discloses a method for preparing sorbitol by continuous hydrogenation of glucose. The technical solution has the following defects: there is no heat recovery device for hydrogenation heating, and the syrup is directly heated to the temperature required by the process by steam, which consumes a lot of energy; the ion exchange uses a weakly acidic acrylic acid cationic resin or a weakly basic styrene anionic resin. The weakly acidic acrylic acid cationic resin can prevent catalyst poisoning, but the removal efficiency of calcium and magnesium ions in liquid sorbitol is not as good as that of the strongly acidic ion exchange resin. Utility Model Content

[0007] The purpose of this section is to summarize some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and utility model name of this application to avoid blurring the purpose of this section, specification abstract and utility model name, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0008] In view of the above problems and / or the problems existing in the prior art, the present utility model is proposed.

[0009] The utility model aims to overcome the problems existing in the prior art and provide a device for hydrogenating and refining sorbitol by crystallization sugar mother liquid, which has good quality of sorbitol syrup, low comprehensive energy consumption, few side reactions and high catalyst reuse rate.

[0010] In order to solve the above technical problems, the utility model provides a device for hydrogenating and refining sorbitol from a crystallized sugar mother liquor, comprising a mother liquor buffer tank, wherein the outlet of the mother liquor buffer tank is connected to the inlet of a pre-hydrogenation buffer tank through a mother liquor delivery pump, the bottom outlet of the pre-hydrogenation buffer tank is connected to the tube-side inlet of a hot water preheater through the pre-hydrogenation delivery pump, the tube-side outlet of the hot water preheater is connected to the tube-side inlet of a steam heater, the tube-side outlet of the steam heater is connected to the inlet of a high-pressure buffer tank, the outlet of the high-pressure buffer tank is connected to the feed port of a catalytic reactor through a high-pressure delivery pump, the sorbitol outlet of the catalytic reactor is connected to the medium inlet of a hot water heat exchanger, the medium outlet of the hot water heat exchanger is connected to the feed port of a settling tank, and the bottom outlet of the settling tank is connected to the catalyst inlet of the pre-hydrogenation buffer tank through a catalyst delivery pump;

[0011] The hot water outlet of the hot water heat exchanger is connected to the shell side inlet of the hot water preheater through a hot water reflux pipe, the shell side outlet of the hot water preheater is connected to the inlet of the hot water circulation tank, and the outlet of the hot water circulation tank is connected to the hot water inlet of the hot water heat exchanger through a hot water circulation pump.

[0012] As an improvement of the utility model, the inlet of the mother liquor delivery pump is connected to the outlet of the alkali adding metering pump, the outlet pipe of the mother liquor delivery pump is provided with a mother liquor pH value sensor, and the alkali adding amount of the alkali adding metering pump is linked to the pH value measured by the mother liquor pH value sensor.

[0013] As a further improvement of the utility model, the feed inlet of the catalytic reactor is connected to a distribution pipe extending toward the center of the bottom of the reactor, and the sorbitol outlet of the catalytic reactor is connected to a discharge pipe extending toward the lower part along the inner wall of the reactor.

[0014] As a further improvement of the utility model, the inner cavity of the catalytic reactor is provided with a reactor coil, the upper inlet of the reactor coil is connected to the steam pipe through a reactor steam regulating valve, and the lower outlet of the reactor coil is connected to the condensate collection pipe through a steam trap.

[0015] As a further improvement of the utility model, the lower end outlet of the reactor coil is also connected to the circulating water supply pipe through a circulating water inlet regulating valve, and the upper end inlet of the reactor coil is also connected to the circulating water return pipe through a circulating water outlet valve.

[0016] As a further improvement of the utility model, a reactor temperature sensor is installed on the reactor wall of the catalytic reactor, and the reactor steam regulating valve and the circulating water inlet regulating valve are respectively controlled by the temperature measured by the reactor temperature sensor.

[0017] As a further improvement of the utility model, the feed port of the catalytic reactor is also connected to the hydrogen supply pipe through a hydrogen intake regulating valve, and the top of the catalytic reactor is connected to the hydrogen discharge pipe through a hydrogen pressure relief regulating valve, and the openings of the hydrogen intake regulating valve and the hydrogen pressure relief regulating valve are respectively controlled by the pressure of the catalytic reactor.

[0018] As a further improvement of the utility model, the feed inlet of the settling tank is provided with a discharge regulating valve, and the opening of the discharge regulating valve is controlled by the pressure of the catalytic reactor.

[0019] As a further improvement of the utility model, a reactor pH sensor is installed at the bottom of the catalytic reactor, and the feed port of the catalytic reactor is connected to the dilute alkali liquid pipe through an alkali liquid regulating valve.

[0020] As a further improvement of the utility model, the sorbitol outlet of the sedimentation tank is connected to the inlet of the sorbitol refining buffer tank through a sorbitol discharge pump, the outlet of the sorbitol refining buffer tank is connected to the hot side inlet of the primary plate cooler through a pre-ion exchange delivery pump, the hot side outlet of the primary plate cooler is connected to an ion exchange unit, the ion exchange unit comprises a weak acid cation exchange column, a strong acid cation exchange column and a weak base anion exchange column connected in series in sequence, the outlet of the ion exchange unit is connected to the inlet of the mixed bed pre-ion exchange buffer tank, the outlet of the mixed bed pre-ion exchange buffer tank is connected to the hot side inlet of the secondary plate cooler through a mixed bed pre-ion exchange delivery pump, and the hot side outlet of the secondary plate cooler is connected to the mixed bed ion exchange system.

[0021] Compared with the prior art, the utility model has achieved the following beneficial effects: 1. In order to ensure the product quality of crystalline sugar and achieve the DX value required by the product, part of the mother liquor produced in the separation process of normal crystalline sugar is refluxed, and the other part of the crystalline sugar mother liquor is hydrogenated and refined to obtain daily chemical grade sorbitol, and the effective ingredients in broken rice are reasonably utilized, so that the broken rice can be comprehensively utilized through deep processing, thereby increasing product additional income, diversifying development, and increasing factory profits.

[0022] 2. Since the hydrogenation process is a high-temperature and high-pressure reaction process, it requires high energy consumption, and it is necessary to comprehensively utilize heat energy to reduce energy consumption. The temperature of the hydrogenation discharge is about 140°C. This system exchanges heat with cold water through a high-pressure heat exchanger, exchanges most of the heat energy to cold water, increases the water temperature, and then preheats the mother liquid through a preheater to reduce the consumption of raw steam, increase the temperature of the hydrogenation reactor, and save energy.

[0023] 3. According to the phenomenon that the catalyst nickel is easily poisoned during the ion exchange process, this device adds a group of weak acid resins before the strong acid ion exchange, that is, the ion exchange process is changed to a weak acid, strong acid and weak base mixed bed, and the catalyst nickel is adsorbed by the weak acid resin. After the weak acid resin is saturated with adsorption, the catalyst nickel can be easily eluted by hydrochloric acid regeneration, which will not cause poisoning and the quality of sorbitol is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. The drawings are only provided for reference and explanation, not for limiting the present utility model. Among them:

[0025] Figure 1 This is a flow chart of the mother liquor hydrogenation refining unit in the utility model;

[0026] Figure 2 This is a flow chart of the sorbitol refining unit in the utility model;

[0027] In the figure: steam pipe 100; circulating water supply pipe 200; circulating water return pipe 300; ice water supply pipe 400; ice water return pipe 500;

[0028] Mother liquor buffer tank 601; mother liquor delivery pump 602; mother liquor pH sensor PH602; pre-hydrogenation buffer tank 603; pre-hydrogenation delivery pump 604; hot water preheater 605; steam heater 606; mother liquor temperature sensor TT606; heating steam regulating valve TC606; high-pressure buffer tank 607; high-pressure delivery pump 608; hot water circulation tank 609; hot water circulation pump 610; diluted alkali storage tank 611; alkali metering pump 612; hydrogen supply pipe 613; hydrogen discharge pipe 614;

[0029] Catalytic reactor 615; reactor temperature sensor TT615; reactor pH sensor PH615; reactor pressure sensor PA615; hydrogen inlet regulating valve PC615-1; hydrogen pressure relief regulating valve PC615-2; reactor steam regulating valve LC615-1; circulating water inlet regulating valve LC615-2; circulating water outlet valve 615-3; alkali liquid regulating valve PHC615;

[0030] Hot water heat exchanger 616; settling tank 617; discharge regulating valve LC617; catalyst delivery pump 618; sorbitol discharge pump 619;

[0031] Sorbitol refining buffer tank 701; pre-ion exchange delivery pump 702; primary plate cooler 703; weak acid cation exchange column 704-1; strong acid cation exchange column 705-1; weak base anion exchange column 706-1; weak acid cation exchange column 704-2; strong acid cation exchange column 705-2; weak base anion exchange column 706-2; booster pump 707; mixed bed pre-ion exchange buffer tank 708; mixed bed pre-ion exchange delivery pump 709; secondary plate cooler 710; mixed bed ion exchange system 711. DETAILED DESCRIPTION

[0032] In the following description of the utility model, the terms "upper", "lower", "front", "back", "left", "right", "inside", "outside", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the utility model and simplifying the description, and do not mean that the device must have a specific direction.

[0033] In order to make the technical means, creative features, objectives and effects of the present invention easier to understand, the present invention is further described below with reference to specific figures. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0035] The utility model discloses a device for refining sorbitol by hydrogenating crystallized sugar mother liquor, which comprises a mother liquor hydrogenating refining unit and a sorbitol refining unit.

[0036] Figure 1 Shown is a mother liquor hydrogenation refining unit, including a mother liquor buffer tank 601, a pre-hydrogenation buffer tank 603, a hot water preheater 605, a steam heater 606, a high-pressure buffer tank 607, a hot water circulation tank 609, a catalytic reactor 615, a hot water heat exchanger 616 and a sedimentation tank 617.

[0037] The outlet of the mother liquid buffer tank 601 is connected to the inlet of the pre-hydrogenation buffer tank 603 through the mother liquid delivery pump 602, the bottom outlet of the pre-hydrogenation buffer tank 603 is connected to the tube side inlet of the hot water preheater 605 through the pre-hydrogenation delivery pump 604, the tube side outlet of the hot water preheater 605 is connected to the tube side inlet of the steam heater 606, and the shell side inlet of the steam heater 606 is connected to the steam pipe 100 through the heating steam regulating valve TC606. The tube side outlet of the steam heater 606 is connected to the inlet of the high-pressure buffer tank 607, the outlet of the high-pressure buffer tank 607 is connected to the feed port of the catalytic reactor 615 through the high-pressure delivery pump 608, the sorbitol outlet of the catalytic reactor 615 is connected to the medium inlet of the hot water heat exchanger 616, the medium outlet of the hot water heat exchanger 616 is connected to the feed port of the settling tank 617, and the bottom outlet of the settling tank 617 is connected to the catalyst inlet of the pre-hydrogenation buffer tank 603 through the catalyst delivery pump 618.

[0038] The hot water outlet of the hot water heat exchanger 616 is connected to the shell side inlet of the hot water preheater 605 through the hot water return pipe and the hot water regulating valve LC605, and the opening of the hot water regulating valve LC605 is linked to the pipe side outlet temperature of the hot water preheater 605; the shell side outlet of the hot water preheater 605 is connected to the inlet of the hot water circulation tank 609, and the outlet of the hot water circulation tank 609 is connected to the hot water inlet of the hot water heat exchanger 616 through the hot water circulation pump 610.

[0039] The inlet of the mother liquor delivery pump 602 is connected to the outlet of the alkali adding metering pump 612. The outlet pipe of the mother liquor delivery pump 602 is provided with a mother liquor pH sensor PH602. The alkali adding amount of the alkali adding metering pump 612 is linked to the pH value measured by the mother liquor pH sensor PH602.

[0040] The feed inlet of the catalytic reactor 615 is connected to a distribution pipe extending toward the center of the bottom of the reactor, and the sorbitol outlet of the catalytic reactor 615 is connected to a discharge pipe extending toward the lower part along the inner wall of the reactor.

[0041] The inner cavity of the catalytic reactor 615 is provided with a reactor coil, the upper inlet of the reactor coil is connected to the steam pipe 100 through the reactor steam regulating valve LC615-1, and the lower outlet of the reactor coil is connected to the condensate collection pipe through the steam trap.

[0042] The lower outlet of the reactor coil is also connected to the circulating water supply pipe 200 through the circulating water inlet regulating valve LC615-2, and the upper inlet of the reactor coil is also connected to the circulating water return pipe 300 through the circulating water outlet valve 615-3.

[0043] A reactor temperature sensor TT615 is installed on the reactor wall of the catalytic reactor 615, and the reactor steam regulating valve LC615-1 and the circulating water inlet regulating valve LC615-2 are respectively controlled by the temperature measured by the reactor temperature sensor TT615.

[0044] A reactor pressure sensor PA615 is provided on the top of the catalytic reactor 615. The feed port of the catalytic reactor 615 is also connected to the hydrogen supply pipe 613 via a hydrogen inlet regulating valve PC615-1. The top of the catalytic reactor 615 is connected to the hydrogen discharge pipe 614 via a hydrogen pressure relief regulating valve PC615-2. The openings of the hydrogen inlet regulating valve PC615-1 and the hydrogen pressure relief regulating valve PC615-2 are respectively controlled by the pressure measured by the reactor pressure sensor PA615.

[0045] The feed port of the settling tank 617 is provided with a discharge regulating valve LC617, and the opening of the discharge regulating valve LC617 is also controlled by the pressure measured by the reactor pressure sensor PA615.

[0046] The 28°C crystallized sugar mother liquor coming out of the crystallization section enters the mother liquor buffer tank 601 for temporary storage, and after the pH value is adjusted by the alkali metering pump 612, it is sent to the pre-hydrogenation buffer tank 603 by the mother liquor delivery pump 602.

[0047] A mother liquor pH sensor PH602 is installed on the outlet pipe of the mother liquor delivery pump 602. The flow rate of the alkali metering pump 612 is automatically linked to the pH value measured by the mother liquor pH sensor PH602 to adjust the pH value of the crystallized sugar mother liquor to 7.8-8.2.

[0048] The mother liquor after adjusting the pH value is added with a catalyst in the pre-hydrogenation buffer tank 603, and then transported to the cold side of the hot water preheater 605 through the pre-hydrogenation delivery pump 604, and indirectly preheated with the hot water on the hot side to increase the mother liquor temperature to 55°C.

[0049] The preheated mother liquor enters the cold side of the steam heater 606 and continues to exchange heat with the steam on the hot side, raising the temperature of the mother liquor to 90-95° C. The opening of the heating steam regulating valve TC606 is linked to the mother liquor outlet temperature of the steam heater 606.

[0050] The mother liquor after heating enters the high-pressure buffer tank 607. The mother liquor discharged from the high-pressure buffer tank 607 is transported to the catalytic reactor 615 through the high-pressure delivery pump 608, and hydrogen is introduced for pressurized catalysis. The catalytic reactor 615 is provided with a reactor coil. The reactor steam regulating valve LC615-1 is opened, and steam is introduced into the reactor coil to indirectly heat the mother liquor to the optimal hydrogenation reaction temperature of 140°C. The pressure in the reactor is 12MPa, and the steam condensate is discharged through the steam trap. After the temperature in the reactor reaches 140°C, the reactor steam regulating valve LC615-1 is closed.

[0051] Since the hydrogenation reaction is an exothermic reaction, in order to prevent the temperature in the reactor from continuing to rise, open the circulating water inlet regulating valve LC615-2 and the circulating water outlet valve 615-3, and pass a certain amount of circulating water into the reactor coil to stabilize the temperature in the reactor at the optimal hydrogenation reaction temperature of 140°C.

[0052] A reactor temperature sensor TT615 is installed on the side wall of the catalytic reactor 615, and the openings of the reactor steam regulating valve LC615-1 and the circulating water inlet regulating valve LC615-2 are both controlled by the temperature measured by the reactor temperature sensor TT615.

[0053] A reactor pH sensor PH615 is installed at the bottom of the catalytic reactor 615, and the feed port of the catalytic reactor 615 is connected to the dilute alkali liquid pipe through the alkali liquid regulating valve PHC615. The pH value will drop during the catalytic process, and the alkali liquid regulating valve PHC615 is interlocked with the reactor pH sensor PH615. The alkali liquid regulating valve PHC615 is used to adjust the pH value of the feed liquid in the catalytic reactor, so that the pH value of the feed liquid in the catalytic reactor is stabilized at 7.8-8.2, so as to achieve the best reaction conditions, reduce the occurrence of side reactions, and improve the catalytic efficiency.

[0054] A reactor pressure sensor PA615 is installed on the top of the catalytic reactor 615. The hydrogen supply pipe is connected to the hydrogen inlet of the catalytic reactor 615 through the hydrogen inlet regulating valve PC615-1. The opening of the hydrogen inlet regulating valve PC615-1 is controlled by the reactor pressure sensor PA615.

[0055] The top of the catalytic reactor 615 is also connected to the hydrogen discharge pipe through the hydrogen pressure relief regulating valve PC615-2, and the opening of the hydrogen pressure relief regulating valve PC615-2 is also controlled by the reactor pressure sensor PA615.

[0056] After the hydrogenation is completed, sorbitol is generated and enters the lower port of the vertical pipe. It is discharged from the top of the catalytic reactor 615 under pressure. The discharged sorbitol first enters the coil of the hot water heat exchanger 616 to exchange heat with hot water, and the temperature of the sorbitol is reduced from 140°C to 90°C. It enters the settling tank 617 through the discharge regulating valve LC617. The opening of the discharge regulating valve LC617 is adjusted according to the reactor pressure, thereby adjusting the amount of liquid entering the settling tank 617.

[0057] The temperature of the hot water after heat exchange with sorbitol rises to above 90°C and returns to the shell inlet of the preheater 605 to preheat the mother liquor on the cold side. The 80°C hot water discharged from the shell side of the preheater 605 enters the hot water circulation tank 609 and is sent to the top of the tank of the hot water heat exchanger 616 by the hot water circulation pump 610 for circulation to cool the sorbitol. The RO water pipe is connected to the top of the hot water circulation tank 609 as supplementary water.

[0058] The sorbitol entering the settling tank 617 is discharged after settling, and the sorbitol catalyst is settled at the bottom of the settling tank 617 and transported to the pre-hydrogenation buffer tank 603 for reuse through the catalyst delivery pump 618. The sorbitol is transported from the middle of the settling tank 617 to the sorbitol refining section through the sorbitol discharge pump 619.

[0059] Figure 2 The figure shows a sorbitol refining unit, wherein the sorbitol outlet of the settling tank 617 is connected to the inlet of the sorbitol refining buffer tank 701 through a sorbitol discharge pump 619, the outlet of the sorbitol refining buffer tank 701 is connected to the hot side inlet of the primary plate cooler 703 through a pre-deionization delivery pump 702, the cold side inlet of the primary plate cooler 703 is connected to the ice water supply pipe 400 through a regulating valve, and the cold side outlet of the primary plate cooler 703 is connected to the ice water return pipe 500; the hot side outlet of the primary plate cooler 703 is connected to an ion exchange unit, and the ion exchange unit includes a weak acid cation exchange unit and a weak acid cation exchange unit connected in series in sequence. The exchange column 704-1, the strong acid cation exchange column 705-1 and the weak base anion exchange column 706-1, the outlet of the ion exchange unit is connected to the inlet of the mixed bed pre-ion exchange buffer tank 708, the outlet of the mixed bed pre-ion exchange buffer tank 708 is connected to the hot side inlet of the secondary plate cooler 710 through the mixed bed pre-ion exchange delivery pump 709, the cold side inlet of the secondary plate cooler 710 is also connected to the ice water supply pipe 400 through the regulating valve, the cold side outlet of the secondary plate cooler 710 is connected to the ice water return pipe 500; the hot side outlet of the secondary plate cooler 710 is connected to the mixed bed ion exchange system 711.

[0060] The sorbitol after hydrogenation and cooling enters the sorbitol refining buffer tank 701, and the sorbitol is transported to the hot side of the primary plate cooler 703 for cooling through the pre-ion exchange delivery pump 702. The sorbitol cooled to 55-60°C enters the ion exchange unit. The ion exchange unit adopts an ion exchange scheme of three groups of weak acid cation exchange columns → strong acid cation exchange columns → weak base anion exchange columns, two of which are operated in series, and one group is used as a standby after acid-base regeneration, forming three groups that are rotated and regenerated.

[0061] As shown in the figure, sorbitol enters weak acid cation exchange column 704-1 → strong acid cation exchange column 705-1 → weak base anion exchange column 706-1 for ion exchange, and then enters weak acid cation exchange column 704-2 → strong acid cation exchange column 705-2 → weak base anion exchange column 706-2 for ion exchange again after being pressurized by booster pump 707. First, the catalyst in sorbitol and the cations in part of the sorbitol sugar solution are removed by weak acid resin, and then the cations such as calcium and magnesium are removed by strong acid cation resin, and then the sulfate and chloride ions in the sorbitol syrup are removed by weak base resin.

[0062] The refined syrup is discharged into the mixed bed pre-ion exchange buffer tank 708. The sorbitol discharged from the mixed bed pre-ion exchange buffer tank 708 is sent to the secondary plate cooler 710 through the mixed bed pre-ion exchange delivery pump 709 to cool down again by 35-38°C, and then enters the mixed bed ion exchange system 711 for further polishing and refining to improve the light transmittance of the sorbitol syrup. The resin in the mixed bed ion exchange system 711 uses strong acid and strong base resin. Polishing with strong base resin can further remove weak alkaline ions in the syrup and improve the quality of sorbitol syrup; the refined sorbitol is evaporated and concentrated into finished products before being sold.

[0063] The above description is only the preferred feasible embodiment of the utility model, which shows and describes the basic principle, main features and advantages of the utility model, but does not limit the scope of patent protection of the utility model. The technicians in this industry should understand that the utility model is not limited by the above embodiments. In addition to the above embodiments, the utility model can also have other implementation modes without departing from the spirit and scope of the utility model. The utility model will also have various changes and improvements. All technical solutions formed by equivalent replacement or equivalent transformation fall within the scope of protection required by the utility model. The scope of protection required by the utility model is defined by the attached claims and their equivalents. The technical features not described in the utility model can be achieved by or using existing technologies, which will not be repeated here.

Claims

1. A device for hydrogenating and refining sorbitol from a crystalline sugar mother liquor, comprising a mother liquor buffer tank (601), characterized in that: The outlet of the mother liquor buffer tank (601) is connected to the inlet of the pre-hydrogenation buffer tank (603) through the mother liquor delivery pump (602), the bottom outlet of the pre-hydrogenation buffer tank (603) is connected to the pipe side inlet of the hot water preheater (605) through the pre-hydrogenation delivery pump (604), the pipe side outlet of the hot water preheater (605) is connected to the pipe side inlet of the steam heater (606), and the pipe side outlet of the steam heater (606) is connected to the inlet of the high-pressure buffer tank (607). The outlet of the high-pressure buffer tank (607) is connected to the feed port of the catalytic reactor (615) via a high-pressure delivery pump (608), the sorbitol outlet of the catalytic reactor (615) is connected to the medium inlet of the hot water heat exchanger (616), the medium outlet of the hot water heat exchanger (616) is connected to the feed port of the settling tank (617), and the bottom outlet of the settling tank (617) is connected to the catalyst inlet of the pre-hydrogenation buffer tank (603) via a catalyst delivery pump (618); The hot water outlet of the hot water heat exchanger (616) is connected to the shell side inlet of the hot water preheater (605) through a hot water return pipe, the shell side outlet of the hot water preheater (605) is connected to the inlet of a hot water circulation tank (609), and the outlet of the hot water circulation tank (609) is connected to the hot water inlet of the hot water heat exchanger (616) through a hot water circulation pump (610).

2. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 1, characterized in that: The inlet of the mother liquor delivery pump (602) is connected to the outlet of the alkali addition metering pump (612), and the outlet pipeline of the mother liquor delivery pump (602) is provided with a mother liquor pH value sensor (PH602). The alkali addition amount of the alkali addition metering pump (612) is linked to the pH value measured by the mother liquor pH value sensor (PH602).

3. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 1, characterized in that: The feed inlet of the catalytic reaction kettle (615) is connected to a distribution pipe extending toward the center of the bottom of the kettle, and the sorbitol outlet of the catalytic reaction kettle (615) is connected to a discharge pipe extending toward the lower part along the inner wall of the kettle.

4. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 1, characterized in that: The inner cavity of the catalytic reactor (615) is provided with a reactor coil, the upper inlet of the reactor coil is connected to the steam pipe (100) through a reactor steam regulating valve (LC615-1), and the lower outlet of the reactor coil is connected to the condensate collection pipe through a steam trap.

5. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 4, characterized in that: The lower end outlet of the reactor coil is also connected to the circulating water supply pipe (200) through the circulating water inlet regulating valve (LC615-2), and the upper end inlet of the reactor coil is also connected to the circulating water return pipe (300) through the circulating water outlet valve (615-3).

6. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 5, characterized in that: A reactor temperature sensor (TT615) is installed on the reactor wall of the catalytic reactor (615), and the reactor steam regulating valve (LC615-1) and the circulating water inlet regulating valve (LC615-2) are respectively controlled by the temperature measured by the reactor temperature sensor (TT615).

7. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 1, characterized in that: The feed port of the catalytic reactor (615) is also connected to the hydrogen supply pipe (613) through a hydrogen intake regulating valve (PC615-1), and the top of the catalytic reactor (615) is connected to the hydrogen discharge pipe (614) through a hydrogen pressure relief regulating valve (PC615-2). The openings of the hydrogen intake regulating valve (PC615-1) and the hydrogen pressure relief regulating valve (PC615-2) are respectively controlled by the pressure of the catalytic reactor (615).

8. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 1, characterized in that: The feed inlet of the settling tank (617) is provided with a discharge regulating valve (LC617), and the opening of the discharge regulating valve (LC617) is controlled by the pressure of the catalytic reactor (615).

9. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to claim 1, characterized in that: A reactor pH sensor (PH615) is installed at the bottom of the catalytic reactor (615), and the feed port of the catalytic reactor (615) is connected to the dilute alkali liquid pipe through an alkali liquid regulating valve (PHC615).

10. The device for hydrogenating and refining sorbitol from crystalline sugar mother liquid according to any one of claims 1 to 9, characterized in that: The sorbitol outlet of the settling tank (617) is connected to the inlet of the sorbitol refining buffer tank (701) through a sorbitol discharge pump (619), and the outlet of the sorbitol refining buffer tank (701) is connected to the hot side inlet of the primary plate cooler (703) through a pre-ion exchange delivery pump (702), and the hot side outlet of the primary plate cooler (703) is connected to an ion exchange unit, wherein the ion exchange unit comprises a weak acid cation exchange column (704-1), a strong acid cation exchange column (705-1) and a weak base anion exchange column (706-1) connected in series in sequence, and the outlet of the ion exchange unit is connected to the inlet of the mixed bed pre-ion exchange buffer tank (708), and the outlet of the mixed bed pre-ion exchange buffer tank (708) is connected to the hot side inlet of the secondary plate cooler (710) through a mixed bed pre-ion exchange delivery pump (709), and the hot side outlet of the secondary plate cooler (710) is connected to a mixed bed ion exchange system (711).

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