Concentration system for producing D-sodium erythorbate

Abstract

The invention relates to a concentration system for producing D-sodium erythorbate, which is characterized in that a spiral blade is arranged in a closed shell of a first-stage spiral concentrator, the upper part of one end of the closed shell is connected with a feeding pipe, and a first-stage discharging pipe is connected between the lower part of the other end of the closed shell and the upper part of a diluting tank; evaporated steam in the closed shell is connected to a first-stage condenser through a steam pipeline, a second-stage spiral concentrator is arranged between the first-stage spiral concentrator and the dilution tank, a first-stage discharging pipe is communicated with an inlet of the second-stage spiral concentrator, and an outlet of the second-stage spiral concentrator is connected to the dilution tank through a second-stage discharging pipe. The system adopts a two-stage step-by-step propulsion mode to concentrate materials, the materials are in a continuous forward spiral stirring propulsion state in the concentration process, and internal moisture is continuously evaporated, so that the materials are prevented from being in large-area contact with an evaporation heat source and being concentrated at a fixed position for a long time, and the phenomena of carbonization and coking caused by wall adhesion of the materials due to over-high temperature can be effectively avoided; the automation is obviously improved, and the evaporation and concentration speed is increased.

Description

Technical Field

[0001] The invention relates to the field of chemical production systems, and in particular to a concentration system for producing sodium D-isoascorbate. Background Art

[0002] Sodium D-isoascorbate is a highly purified and stable compound, mainly used in food preservation, antiseptic and color enhancement.

[0003] The preparation of sodium D-isoascorbate usually involves two main steps: microbial fermentation and chemical conversion. First, the precursor 2-keto-D-gluconic acid (2-KGA) is obtained by fermentation with microorganisms (such as Pseudomonas or Serratia marcescens), and then 2-KGA is converted into sodium D-isoascorbate by chemical methods (such as esterification reaction and conversion reaction).

[0004] Before chemical conversion, the high-concentration solution with a high content of precursor substances needs to be evaporated and concentrated to reduce the water content and improve the chemical conversion efficiency. At present, the concentration is mainly carried out through enameled reactors. The disadvantages of this method are: (1) Enameled reactors need to be concentrated tank by tank, and after a tank is concentrated, it is emptied and refilled with solution. The operation is complicated and the workload is large. The concentration end point needs to be manually judged, and the material quality stability is poor; (2) When the material is concentrated to the end point, it is close to anhydrous state, with poor fluidity and very viscous, and it is very easy to stop the stirring paddle and cause shutdown; (3) The concentrated solution is heat-sensitive and requires a liquid phase temperature of ≤60°C. At present, 150°C steam is usually used to heat the reactor. The solution is stirred and concentrated in the reactor for a long time, which is prone to the phenomenon of excessive temperature and solution sticking to the wall, resulting in overheating and carbonization of the solution, affecting the product yield and evaporation efficiency. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a concentration system for producing sodium D-isoascorbate.

[0006] The technical scheme of the present invention is: a concentrating system for the production of sodium D-isoascorbate, comprising a primary spiral concentrator and a dilution tank, wherein a spiral blade is installed in a closed shell of the primary spiral concentrator, and the spiral blade is driven to rotate by a reduction motor, the upper part of one end of the closed shell is connected to a material supply pipe, and a primary discharge pipe is connected between the lower part of the other end and the upper part of the dilution tank, and a primary discharge pump is connected to the primary discharge pipe, and an alcoholization delivery pipe is provided at the outlet of the lower end of the dilution tank, and a methanol filling pipe and a sewage pipe are connected to the alcoholization delivery pipe, and the evaporated steam in the closed shell is connected to the inlet of the primary condenser through a steam pipeline; a secondary spiral concentrator is provided between the primary spiral concentrator and the dilution tank, the primary discharge pipe leads to the inlet of the secondary spiral concentrator, the outlet of the secondary spiral concentrator is connected to the dilution tank through a secondary discharge pipe, and the secondary discharge pipe is connected to the secondary discharge pump, and the evaporated steam in the closed shell of the secondary spiral concentrator is connected to the inlet of the secondary condenser through a steam pipeline.

[0007] Preferably, a primary circulation pipe is provided on the primary discharge pipe between the primary discharge pump and the secondary spiral concentrator, and the primary circulation pipe is connected to the primary spiral concentrator.

[0008] Preferably, a secondary circulation pipe is provided on the secondary discharge pipe between the secondary discharge pump and the dilution tank, and the secondary circulation pipe is connected to the secondary spiral concentrator.

[0009] Preferably, the system is also provided with a heat source water tank, the upper end of the heat source water tank is connected to the steam source through a pipeline, and a drain pipe is provided at the outlet of the upper end. The drain pipe passes into the sealed spiral shafts of the first-stage spiral concentrator and the second-stage spiral concentrator through a drainage branch pipe and is connected to the coil on the outer side of the closed shell, and is connected to the lower end of the heat source water tank through a return pipe, and a water pump is provided on the return pipe.

[0010] Preferably, the condensate outlets of the primary condenser and the secondary condenser are connected to a water tank through water pipes, the outlet pipes are connected to a vacuum pump, the housing of the vacuum pump is connected to an ethylene glycol inlet pipe, the outlet of the vacuum pump is provided with an ethylene glycol outlet pipe, and a plate heat exchanger is provided between the ethylene glycol inlet pipe and the ethylene glycol outlet pipe.

[0011] Preferably, the incoming pipe and the first-level discharge pipe are both provided with automatic valves, and the closed shell of the first-level spiral concentrator is provided with a liquid level sensor, which is connected to the automatic valve of the incoming pipe through a signal line to achieve interlocking. The closed shell of the first-level spiral concentrator is provided with a liquid level sensor, which is connected to the automatic valve of the first-level discharge pipe through a signal line to achieve interlocking.

[0012] Preferably, a bubble filling pipe is provided on the sealed shell of the first-stage spiral concentrator, and a water injection pipe and an emptying pipe are provided on the sealed shells of the first-stage spiral concentrator and the second-stage spiral concentrator.

[0013] The beneficial technical effects of the present invention are: (1) The system innovatively uses a spiral concentrator as a concentration carrier. After the high-concentration solution enters the spiral concentrator, it can be pushed forward at a uniform speed while evaporating under the action of the spiral blades. The material concentrated to a very viscous state can also be pushed forward smoothly, ensuring the continuous and efficient operation of the concentration process. It solves the problems of complex concentration operation and heavy workload in traditional enamel reactors and improves the stability of material quality.

[0014] (2) The system uses a two-stage step-by-step method to concentrate materials. During the concentration process, the material is in a state of continuous forward spiral stirring and propulsion, while water is continuously evaporated, avoiding large-area contact between the material and the evaporation heat source and long-term concentration at a fixed position. This can effectively avoid the phenomenon of material sticking to the wall due to excessive temperature, leading to carbonization and coking, facilitates process control, significantly improves automation, and greatly increases the speed of evaporation and concentration. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a system diagram of the present invention.

[0016] In the figure, 01. first-stage spiral concentrator, 11. spiral blade, 12. reduction motor, 14. feed pipe, 15. first-stage discharge pipe, 16. first-stage discharge pump, 17. first-stage condenser, 18. first-stage circulation pipe, 19. steam pipeline, 02. second-stage spiral concentrator, 21. second-stage discharge pipe, 22. second-stage discharge pump, 23. second-stage condenser, 24. second-stage circulation pipe, 03. dilution tank, 31. alcoholization delivery pipe, 32. methanol filling pipe, 33. sewage pipe, 04. heat source water tank, 43. drainage branch pipe, 44. return pipe, 45. water pump, 51. water tank, 52. ethylene glycol inlet pipe, 53. ethylene glycol discharge pipe, 54. plate heat exchanger, 55. vacuum pump, 61. automatic valve, 62. signal line, 63. liquid level sensor. DETAILED DESCRIPTION

[0017] Embodiment 1, see attached Figure 1A concentration system for the production of sodium D-isoascorbate, comprising a primary spiral concentrator 01 and a dilution tank 03, wherein a spiral blade 11 is installed in a closed shell of the primary spiral concentrator 01, and the spiral blade 11 is driven to rotate by a reduction motor 12, the upper part of one end of the closed shell is connected to a feed pipe 14, and a primary discharge pipe 15 is connected between the lower part of the other end and the upper part of the dilution tank 03, and a primary discharge pump 16 is connected to the primary discharge pipe 15, and the solution material pushed forward in the spiral concentrator is sucked out in time into the discharge pipe by the discharge pump, and an alcoholization delivery pipe 31 is provided at the outlet of the lower end of the dilution tank 03, and a methanol filling pipe 32 and a sewage pipe 33 are connected to the alcoholization delivery pipe 31, methanol is added to the dilution tank 03 from the methanol filling pipe 32, and dirty impurities generated by long-term use in the dilution tank 03 are discharged from the sewage pipe 33, and the closed shell The evaporation steam inside is connected to the inlet of the primary condenser 17 through the steam pipe 19. The evaporation of water prevents the material from contacting the evaporation heat source over a large area and for a long time, and from being concentrated in a fixed position for a long time, which can effectively prevent the material from sticking to the wall and causing carbonization and coking due to excessive temperature. A secondary spiral concentrator 02 is arranged between the primary spiral concentrator 01 and the dilution tank 03. The primary discharge pipe 15 leads to the inlet of the secondary spiral concentrator 02. The outlet of the secondary spiral concentrator 02 is connected to the dilution tank 03 through the secondary discharge pipe 21. The secondary discharge pipe 21 is connected to a secondary discharge pump 22. The evaporation steam in the secondary spiral concentrator 02 is connected to the inlet of the secondary condenser 23 through the steam pipe 19. The material is concentrated in a two-stage step-by-step manner. During the concentration process, the material is in a state of continuous forward spiral stirring and propulsion, which is convenient for process control and significantly improves automation.

[0018] A primary circulation pipe 18 is provided on the primary discharge pipe 15 between the primary discharge pump 16 and the secondary spiral concentrator 02, and the primary circulation pipe 18 is connected to the primary spiral concentrator 01; a secondary circulation pipe 24 is provided on the secondary discharge pipe 21 between the secondary discharge pump 22 and the dilution tank 03, and the secondary circulation pipe 24 is connected to the secondary spiral concentrator 02. Valves are provided on both the primary circulation pipe 18 and the secondary circulation pipe 24, and the on-off of the circulation pipe and the discharge pipe is controlled by the valve. When circulation is required, the valve is opened, and the material circulates and concentrates between the spiral concentrator, the discharge pipe and the circulation pipe until the set specific gravity is reached.

[0019] The condensate outlets of the primary condenser 17 and the secondary condenser 23 are connected to the water tank 51 through water pipes, and a vacuum pump 55 is connected to the outlet pipe. An ethylene glycol inlet pipe 52 is connected to the shell of the vacuum pump 55, and an ethylene glycol outlet pipe 53 is provided at the outlet of the vacuum pump 55. A plate heat exchanger 54 is provided between the ethylene glycol inlet pipe 52 and the ethylene glycol outlet pipe 53. The hot steam generated by evaporation passes through the condenser to condense the water inside the hot steam for recycling and reuse, which is beneficial to saving production costs. At the same time, the continuous operation of the vacuum pump 55 will cause its own operating temperature to be too high due to the hot steam. Ethylene glycol is introduced into the vacuum pump 55 as a refrigerant to circulate and cool it, ensuring that it is at the optimal operating temperature and prolonging its service life.

[0020] A foam filling pipe is provided on the closed shell of the first-stage spiral concentrator 01. A large amount of foam will be generated inside the spiral concentrator in the early stage of concentration. At this time, foam is added from the foam filling pipe to reduce the surface tension of the solution and eliminate the generated foam. A water injection pipe and an emptying pipe are provided on the closed shells of the first-stage spiral concentrator 01 and the second-stage spiral concentrator 02.

[0021] The method of using the concentration system is: Start the vacuum pump 55 of the primary condenser 17 and the secondary condenser 23 to evacuate. The first-stage spiral concentrator 01 and the second-stage spiral concentrator 02 are evacuated to -0.095Mpa through the condenser; Open the valve on the feed pipe 14, and the liquid material enters the first-stage spiral concentrator 01 After reaching the set position, the first-stage spiral concentrator 01 and the second-stage spiral concentrator 02 are started, and the solution material is evaporated and pushed forward at a uniform speed under the action of the spiral blades 11 to achieve first-stage concentration, and is discharged from the first-stage discharge pipe 15 to enter the second-stage spiral concentrator 02 for second-stage concentration. During this process, attention is paid to the changes in the vapor phase temperature and liquid phase temperature of the spiral concentrator to ensure that the material is continuously concentrated under negative pressure and low temperature conditions; After two-stage concentration and reaching a predetermined specific gravity, the material enters the secondary discharge pipe 21. Dilution tank, dilution tank 03 is equipped with a weighing module. After the concentrated material enters dilution tank 032-KG dry weight reaches a batch volume, methanol is added from methanol filling pipe 32 for dilution, and transferred to the next alcoholization process through the pump of dilution tank 03; The steam generated during the material concentration process enters the condenser, and the condenser The water is condensed and recycled into the water tank 51 for reuse, and ethylene glycol is introduced into the vacuum pump 55 as a refrigerant to circulate and cool it, thereby ensuring that it is at an optimal working temperature.

[0022] Embodiment 2, see attached Figure 1This embodiment is basically the same as the first embodiment, except that the system is further provided with a heat source water tank 04, the upper end of which is connected to a steam source through a pipeline, and the water inside the heat source water tank 04 is heated by hot steam from the production system, and a drain pipe is provided at the outlet of the upper end, which is passed into the spiral shafts of the first-stage spiral concentrator 01 and the second-stage spiral concentrator 02 through a drain branch pipe 43 and connected to the coil on the outer side of the sealed shell, and is connected to the lower end of the heat source water tank 04 through a return pipe 44, and a water pump 45 is provided on the return pipe 44. The hot water in the heat source water tank 04 is sent to the drain pipe through the water pump 45, and then enters each drain branch pipe 43 from the drain pipe, and enters the hollow spiral shaft and the coil on the outer side of the sealed shell from the drain branch pipe 43, respectively, to heat the spiral concentrator from the inside and outside, increase the heat exchange area, ensure that the internal materials are evenly heated, and the hot water heating can avoid the problem of excessively high heating temperature of the hot steam, so as to realize the low-temperature continuous and efficient concentration operation of the system.

[0023] Embodiment 3, see attached Figure 1 This embodiment is basically the same as the first embodiment, except that: the system's feed pipe 14 and the first-stage discharge pipe 15 are both provided with automatic valves 61, the first-stage spiral concentrator 01's sealed shell is provided with a liquid level sensor 63, the liquid level sensor 63 is connected to the automatic valve 61 of the feed pipe 14 through a signal line 62 to achieve interlocking, and the first-stage spiral concentrator 01's sealed shell is provided with a liquid level sensor 63, the liquid level sensor 63 is connected to the automatic valve 61 of the first-stage discharge pipe 15 through a signal line 62 to achieve interlocking. When the liquid level inside the spiral concentrator is high, it will affect the spiral propulsion speed and evaporation effect. This embodiment can monitor the internal liquid level in real time through the liquid level sensor 63. When the liquid level exceeds the set value, the sensor sends the signal to the controller of the automatic valve 61, and the opening of the automatic valve 61 is reduced or closed, and a chain control is formed between the two to ensure that the liquid level inside the spiral concentrator is in a stable state and the spiral propulsion concentration effect is ensured.

Claims

1. A concentration system for the production of sodium D-isoascorbate, characterized in that: It comprises a primary spiral concentrator and a dilution tank. A spiral blade is installed in the sealed shell of the primary spiral concentrator. The spiral blade is driven to rotate by a reduction motor. The upper part of one end of the sealed shell is connected to the feed pipe, and a primary discharge pipe is connected between the lower part of the other end and the upper part of the dilution tank. The primary discharge pipe is connected to a primary discharge pump. An alcoholization delivery pipe is provided at the outlet of the lower end of the dilution tank. A methanol filling pipe and a sewage pipe are connected to the alcoholization delivery pipe. The evaporated steam in the sealed shell is connected to the inlet of the primary condenser through a steam pipeline. A secondary spiral concentrator is provided between the primary spiral concentrator and the dilution tank. The primary discharge pipe leads to the inlet of the secondary spiral concentrator. The outlet of the secondary spiral concentrator is connected to the dilution tank through a secondary discharge pipe. The secondary discharge pipe is connected to a secondary discharge pump. The evaporated steam in the sealed shell of the secondary spiral concentrator is connected to the inlet of the secondary condenser through a steam pipeline.

2. A concentration system for the production of sodium D-isoascorbate according to claim 1, characterized in that: A primary circulation pipe is arranged on the primary discharge pipe between the primary discharge pump and the secondary spiral concentrator, and the primary circulation pipe is connected to the primary spiral concentrator.

3. A concentration system for the production of sodium D-isoascorbate according to claim 2, characterized in that: A secondary circulation pipe is provided on the secondary discharge pipe between the secondary discharge pump and the dilution tank, and the secondary circulation pipe is connected to the secondary spiral concentrator.

4. A concentration system for the production of sodium D-isoascorbate according to claim 1, characterized in that: The system is also provided with a heat source water tank, the upper end of which is connected to the steam source through a pipeline, and a drain pipe is provided at the outlet of the upper end. The drain pipe passes through a drainage branch pipe into the sealed spiral shafts of the first-stage spiral concentrator and the second-stage spiral concentrator and is connected to the coil on the outer side of the closed shell, and is connected to the lower end of the heat source water tank through a return pipe, and a water pump is provided on the return pipe.

5. A concentration system for the production of sodium D-isoascorbate according to claim 1, characterized in that: The condensation water outlets of the primary condenser and the secondary condenser are connected to a water tank through water pipes, and a vacuum pump is connected to the outlet pipe. An ethylene glycol inlet pipe is connected to the housing of the vacuum pump, and an ethylene glycol outlet pipe is provided at the outlet of the vacuum pump, and a plate heat exchanger is provided between the ethylene glycol inlet pipe and the ethylene glycol outlet pipe.

6. A concentration system for the production of sodium D-isoascorbate according to claim 1, characterized in that: The inlet pipe and the first-level discharge pipe are both provided with automatic valves. The closed shell of the first-level spiral concentrator is provided with a liquid level sensor, which is connected to the automatic valve of the inlet pipe through a signal line to achieve interlocking. The closed shell of the first-level spiral concentrator is provided with a liquid level sensor, which is connected to the automatic valve of the first-level discharge pipe through a signal line to achieve interlocking.

7. A concentration system for the production of sodium D-isoascorbate according to claim 1, characterized in that: The sealed shell of the first-stage spiral concentrator is provided with a bubble filling pipe, and the sealed shells of the first-stage spiral concentrator and the second-stage spiral concentrator are provided with a water injection pipe and an emptying pipe.

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