Equipment for recovering acid and xylose from alkali-containing hemicellulose

Abstract

The utility model discloses equipment for recovering acid and xylose from alkali-containing hemicellulose, which comprises a hydrolysis device, a chromatographic deacidification device, an electrodialysis desalination device and an evaporation device, and the chromatographic deacidification device comprises a tank body, a chromatographic separation column, a hemicellulose hydrolysate feed port and an acid outlet. A chromatographic separation column of the chromatographic deacidification device is of a plurality of tubular structures which are arranged in parallel, and a spraying unit is arranged between the hemicellulose hydrolysate feeding hole and the chromatographic separation column; the equipment further comprises a water softening device, and the acid outlet of the chromatographic deacidification device is communicated with the water softening device. According to the chromatographic deacidification device, compared with the traditional mode that a single ion exchange column is divided into a plurality of tubular structures, the height-diameter ratio of the ion exchange column is greatly improved, so that the speed of cellulose hydrolysate entering the ion exchange column is controlled in the whole process, and the flowing uniformity is ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of xylose production equipment, in particular to equipment for recovering acid and xylose from alkali-containing hemicellulose. Background Art

[0002] Currently, hemicellulose is the primary raw material for xylose production. The specific process for producing xylose is as follows: Using hemicellulose as the raw material, sulfuric acid is added to the hemicellulose under heating conditions. The sulfuric acid hydrolyzes the hemicellulose into xylose and other sugars. This hydrolyzate contains impurities such as salt (sodium sulfate) and acid (sulfuric acid). Therefore, to improve the quality of xylose, it is necessary to effectively remove these impurities from the hemicellulose hydrolyzate.

[0003] The existing xylose setting includes a hydrolysis device, a chromatographic deacidification device, an electrodialysis desalination device and an evaporation device for removing salt and acid. On the one hand, ion exchange column chromatography is used in the chromatographic deacidification device to improve the purity of xylose. The ion exchange column reactor used in ion chromatography is based on a single column. The structural configuration of the reactor feed port and the single column is prone to uneven liquid flow. The uneven liquid flow will affect the contact time and exchange effect between the resin and the xylose solution. The xylose solution is not in sufficient contact with the resin, and the impurities are not completely removed, resulting in a decrease in the performance of the ion exchange column and the inability to exert the full performance of the equipment. On the other hand, in the chromatographic deacidification device, due to the frequent use of the single-column ion exchange reactor, a certain amount of acid solution tends to accumulate inside it. In order to completely remove these acid solutions, the single-column ion exchange reactor needs to be removed from the equipment, and the deacidification equipment needs to be flushed with steam to remove the acid solution from the ion exchange column. However, the removal and removal operations will reduce the efficiency of the equipment. Utility Model Content

[0004] The utility model aims to solve the problems in the existing single-column centrifugal reactor that the centrifugal performance is reduced due to uneven liquid flow and the efficiency of the equipment is reduced by the back-and-forth taking-out and removing operations in the single-column centrifugal reactor, and proposes a device for recovering acid and xylose from alkali-containing hemicellulose.

[0005] The technical method of the utility model is as follows:

[0006] A device for recovering acid and xylose from alkali-containing hemicellulose, comprising a hydrolysis device, a chromatographic deacidification device, an electrodialysis desalination device and an evaporation device. The chromatographic deacidification device comprises a tank body, a chromatographic separation column, a hemicellulose hydrolyzate feed port and an acid outlet. The device is characterized in that the chromatographic separation columns of the chromatographic deacidification device are a plurality of parallel arranged shell-and-tube structures, a spray unit is provided between the hemicellulose hydrolyzate feed port and the chromatographic separation columns; the device also comprises a water softening device, and the acid outlet of the chromatographic deacidification device is connected to the water softening device.

[0007] The softening device is provided with a deacidification water tank, a softening water tank, a softening water pump and a pipeline; the deacidification water tank is provided with an acid inlet and an acid outlet, the acid inlet of the deacidification water tank is connected to the acid outlet of the chromatographic deacidification device, the acid outlet of the deacidification water tank is connected to the softening water tank, one end of the pipeline is connected to the softening water tank through the softening water pump, and the other end is connected to the hemicellulose hydrolyzate feed port.

[0008] The hydrolysis device is provided with a hydrolysis kettle, one end of which is connected to a discharge port of hemicellulose hydrolyzate, and the other end is connected to a feed port of alkali-containing hemicellulose raw material.

[0009] The electrodialysis desalination device is provided with a high-sugar solution feed port, an electrodialysis unit, a fresh water discharge port and a concentrated water discharge port. One end of the electrodialysis unit is connected to the high-sugar solution feed port, and the high-sugar solution feed port is connected to the high-sugar solution discharge port, and the other end is connected to the fresh water discharge port and the concentrated water discharge port respectively; the concentrated water discharge port is connected to the evaporation device, and the fresh water discharge port is connected to the external discharge channel.

[0010] The electrodialysis desalination unit includes at least one electrodialyzer.

[0011] The utility model further comprises an ion exchange device, and the fresh water discharge port of the electrodialysis desalination device is connected to the ion exchange device through an external discharge channel.

[0012] In the present invention, the spray unit includes an annular distribution pipe, which is connected to the hemicellulose hydrolyzate feed port. The inner side of the annular distribution pipe is connected to several transverse distribution pipes connected to the annular distribution pipe, and a through hole for liquid to flow into multiple tube-in-tube structures is provided below the transverse distribution pipe.

[0013] The tank body is provided with an upper tube distribution plate and a lower tube distribution plate, and the chromatographic separation column is installed between the upper and lower tube distribution plates; the tank body includes an upper cylinder, a middle cylinder and a lower cylinder connected in sequence, the upper tube distribution plate is installed between the upper cylinder and the middle cylinder, and the lower tube distribution plate is installed between the middle cylinder and the lower cylinder.

[0014] The lower cylinder is conical, and an acid liquid discharge port and a high sugar liquid discharge port are provided at the lower part.

[0015] The utility model has the following beneficial effects:

[0016] 1) In the chromatographic deacidification device, the utility model significantly improves the height-to-diameter ratio of the ion exchange column compared to the traditional single ion exchange column divided into multiple tubular structures, thereby controlling the speed of the cellulose hydrolyzate entering the ion exchange column throughout the process and ensuring the uniformity of the flow.

[0017] 2) The utility model is provided with a spray device consisting of an annular distribution pipe and a transverse distribution pipe. On the one hand, the annular distribution pipe is connected to multiple transverse distribution pipes. When the cellulose hydrolyzate flows into the annular distribution pipe and then flows into multiple transverse distribution pipes, the cellulose hydrolyzate finally flows into multiple tube-arrayed ion exchange columns from the through holes of the transverse distribution pipes, ensuring that the flow of the cellulose hydrolyzate has only two components, parallel to the tube bundle and perpendicular to the tube bundle, further ensuring the uniformity of the flow, thereby ensuring that the performance of the ion exchange column is not affected.

[0018] 3) The utility model is provided with a softening water device, which softens and deacidifies the acid liquid of the chromatographic deacidification device in a deacidification soft tank, and then the deacidified liquid enters the soft water tank. Finally, under the action of a water pump, the liquid in the soft water tank is passed through a pipeline into the hemicellulose hydrolyzate feed port to flush the chromatographic separation column and discharge the acid liquid inside the chromatographic separation column, thereby avoiding the problem of low equipment efficiency caused by taking out the single-column ion exchange reactor column for deacidification.

[0019] 4) The utility model is provided with an ion exchange device, which is used to treat the fresh water discharged from the fresh water outlet.

[0020] 5) The present invention uses a hydrolysis device to hydrolyze alkali-containing hemicellulose, uses a chromatographic deacidification device to deacidify the cellulose hydrolyzate to obtain an acid solution and a high-sugar solution, uses an electrodialysis desalination device to perform electrodialysis desalination on the high-sugar solution to obtain concentrated water and fresh water, and uses an evaporation device to evaporate the concentrated water to obtain xylose. Compared with the prior art that adds salt and / or acid, the present invention uses a chromatographic deacidification device to remove acid, an electrodialysis desalination device to desalinate, and an evaporation device to concentrate and desalinate to recover xylose, thereby increasing the yield of xylose, with a yield of greater than 98%.

[0021] 6) The utility model effectively avoids the introduction of new impurities by using a chromatographic deacidification device and an electrodialysis desalination device. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is the first flow chart of the equipment for recovering acid and xylose from alkali-containing hemicellulose of the utility model;

[0023] Figure 2 This is the second flow chart of the equipment for recovering acid and xylose from alkali-containing hemicellulose of the utility model;

[0024] Figure 3 It is a schematic flow diagram of the hydrolysis kettle of the utility model;

[0025] Figure 4 This is a schematic structural diagram of the chromatographic deacidification device and the water softening device of the present invention;

[0026] Figure 5 This is a first structural schematic diagram of the tank body of the present utility model;

[0027] Figure 6 This is a second structural schematic diagram of the tank body of the present utility model;

[0028] Figure 7 This is a third structural schematic diagram of the tank body of the present utility model;

[0029] Figure 8 This is a fourth structural schematic diagram of the tank body of the present utility model;

[0030] Figure 9 This is a diagram of the internal materials of the tank body of the present utility model;

[0031] Figure 10 This is a flow chart of membrane concentration of the utility model;

[0032] Figure 11 This is a schematic structural diagram of the first electrodialyzer of the present invention;

[0033] Figure 12 This is a structural diagram of the MVR evaporator of the present utility model.

[0034] In the picture:

[0035] 1-Hydrolysis device, 11-Hydrolysis kettle, 12-Hydrolysis liquid temporary storage tank, 2-Chromatographic deacidification device, 21-Tank, 211-Upper cylinder, 2111-Inspection observation hole, 2112-First feed port, 2113-Second feed port, 2114-Annular distribution pipe, 2115-Horizontal distribution pipe, 2116-Upper tube distribution plate, 212-Middle cylinder, 2121-Chromatographic separation column, 21211-Bottom hole, 213-Lower cylinder, 2131-Support frame, 2132-High sugar liquid discharge port, 2133-Lower tube distribution plate, 2134-Acid outlet, 214-Lifting ear, 215-High sugar liquid pump, 22- Acid solution storage tank, 23-high sugar solution storage tank, 3-electrodialysis desalination device, 31-electrodialysis unit, 311-first electrodialyzer, 3111-anode chamber, 3112-cathode chamber, 3113-concentrate chamber, 3114-dilute chamber, 312-second electrodialyzer, 313-third electrodialyzer, 32-desalted water storage tank, 33-fresh water storage tank, 34-concentrate water storage tank, 4-evaporation device, 41-MVR evaporator, 42-concentrate storage tank, 43-evaporation condensate storage tank, 5-softening device, 51-deacidification water tank, 52-softening water tank, 53-softening water pump, 54-pipeline, 6-ion exchange device. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below through specific implementation cases and accompanying drawings. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of protection of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art are all within the scope of the claims attached to this application.

[0037] The utility model provides a device for recovering acid and xylose from alkali-containing hemicellulose, such as Figures 1 to 9 As shown, the equipment includes: a hydrolysis device 1, a chromatographic deacidification device 2, an electrodialysis desalination device 3, and an evaporation device 4.

[0038] In one embodiment, if Figure 1 and Figure 2 As shown, the hydrolysis device 1 is provided with a hydrolysis kettle 11, one end of the hydrolysis kettle 11 is connected to the discharge port of the hemicellulose hydrolyzate, and the other end is connected to the feed port of the alkali-containing hemicellulose raw material.

[0039] Preferably, the hydrolysis device 1 further comprises a hydrolyzed liquid temporary storage tank 12. The hydrolysis kettle 11 is connected to the hydrolyzed liquid temporary storage tank 12 for storing the cellulose hydrolyzed liquid.

[0040] In one embodiment, if Figures 1 to 9 As shown, the chromatographic deacidification device 2 includes a tank 21, a chromatographic separation column 2121, a hemicellulose hydrolyzate feed port, and an acid outlet. The chromatographic separation columns 2121 of the chromatographic deacidification device are multiple, parallel, tubular structures. A spray unit is provided between the hemicellulose hydrolyzate feed port and the chromatographic separation columns 2121. The apparatus also includes a water softening device 5, with the acid outlet of the chromatographic deacidification device 2 connected to the water softening device 5.

[0041] Specifically, an upper tube distribution plate 2116 and a lower tube distribution plate 2132 are provided in the tank body 21. Both the upper tube distribution plate 2116 and the lower tube distribution plate 2132 are provided with multiple through holes. The purpose of providing the through holes in the upper tube distribution plate 2116 is to allow the material to flow into the middle cylinder 212, and the purpose of providing the through holes in the lower tube distribution plate 2132 is to allow the material to flow into the lower cylinder 213. The upper tube distribution plate 2116 is also provided with a lifting ear 214, the purpose of which is to easily remove the upper tube distribution plate 2116 from the reactor. The tubes 2121 are installed between the upper and lower tube distribution plates 2132.

[0042] The tank body 21 comprises an upper body 211, a middle body 212, and a lower body 213, which are connected in sequence. An upper tube distribution plate 2116 is installed between the upper and middle bodies 211 and 212, and a lower tube distribution plate 2132 is installed between the middle and lower bodies 212 and 213. The upper body 211 is also provided with an inspection and observation hole 2111. The middle body 212 is provided with a filtrate outlet 2122. The lower body 213 is conical in shape, with an acid outlet 2134 and a high-sugar liquid outlet 2132 at the bottom. The lower body 213 is also provided with a support frame 2131 for fixing.

[0043] Preferably, side holes are provided on the side walls of the tubes; filter cloth is also provided on the tube walls; the diameter of the side holes is 1-2 mm, and the pore size of the filter cloth is 200-300 meshes. The purpose of providing the side holes and the filter cloth on the tube column is to filter water.

[0044] Preferably, the tank body 21 has a mobile phase (high sugar solution, i.e. xylose syrup), a stationary phase (organic copolymer resin polystyrene type resin quartz sand), and a filter phase (cotton fiber or PEEK-sealing layer or filter layer) from top to bottom.

[0045] Specifically, the spraying device includes an annular distribution pipe 2114, and the hemicellulose hydrolyzate feed port has a first feed port 2112 and a second feed port 2113. The hemicellulose hydrolyzate feed port is connected to the annular distribution pipe 2114, and the inner side of the annular distribution pipe 2114 is connected to several transverse distribution pipes 2115 that are connected to the annular distribution pipe 2114; a through hole for liquid to flow into the chromatographic separation column 2121 is provided below the transverse distribution pipe 2115. When the feed liquid enters the annular distribution pipe 2114 from the hemicellulose hydrolyzate feed port, the feed liquid in the annular distribution pipe 2114 enters multiple transverse distribution pipes 2115, so that the feed liquid enters the chromatographic separation column 2121 of the middle cylinder 212 through the through hole of the transverse distribution pipe 2115.

[0046] Preferably, a plurality of bottom holes 21211 are provided below the chromatographic separation column 2121 .

[0047] Specifically, the softening device 5 is provided with a deacidification water tank 51, a softening water tank 52, a softening water pump 53 and a pipeline 54. The deacidification water tank 51 is provided with an acid inlet and an acid outlet. The acid inlet of the deacidification water tank 51 is connected to the acid outlet of the chromatographic deacidification device 2, and the acid outlet of the deacidification water tank 51 is connected to the softening water tank. One end of the pipeline 54 is connected to the softening water tank 54 through the softening water pump 53, and the other end is connected to the hemicellulose hydrolyzate feed port.

[0048] Furthermore, if Figure 10 As shown, the device may further include a membrane concentration device, which is connected to the chromatographic deacidification device 2 and is used to concentrate and recover inorganic acid. The recovered inorganic acid can be reused.

[0049] Preferably, the membrane concentration device is provided with a membrane concentrate tank and a membrane dialysate tank. The acid solution flows out of the dialysate and the concentrate respectively through the membrane concentration device, the dialysate is stored in the membrane dialysate tank, and the membrane concentrate is stored in the membrane concentrate tank. Here, the membrane concentration device uses a concentration membrane. The concentration membrane is an acid-resistant membrane with a processing capacity of 100-125m 3 / h, the sulfuric acid concentration can be concentrated to about 2%.

[0050] Furthermore, the tank body 21 is connected to the acid solution temporary storage tank 22 and the high sugar solution temporary storage tank 23 respectively, and is used to store the acid solution and the high sugar solution.

[0051] Furthermore, the device further includes a high-sugar liquid pump 215 , and the tank body 21 is connected to the high-sugar liquid pump 215 .

[0052] In one embodiment, if Figures 1 to 9 As shown, the electrodialysis desalination device 3 is equipped with a high-sugar solution feed port, an electrodialysis unit 31, a freshwater discharge port, and a concentrated water discharge port. One end of the electrodialysis unit 31 is connected to the high-sugar solution feed port, which is then connected to the high-sugar solution discharge port. The other end of the electrodialysis unit 31 is connected to the concentrated water discharge port and the freshwater discharge port, respectively. The concentrated water discharge port is connected to the evaporation device 4. The fresh water discharge port is connected to the external discharge channel.

[0053] Furthermore, the equipment also includes an ion exchange device 6, and the fresh water discharge port is connected to the ion exchange device 6 through an external discharge channel.

[0054] In one embodiment, if Figures 1 to 11 As shown, the electrodialysis desalination unit includes at least one electrodialyzer, such as Figure 11 As shown, the first electrodialyzer 311 is provided with an anode chamber 3111, an anodic chamber 3111, three concentrate chambers 3113, and two dilute chambers 3114. The dilute chambers 3114 and concentrate chambers 3113 are alternately arranged between the anode chamber 3111 and the anodic chamber 3111. The anode chamber 3111 and the anodic chamber 3111 are adjacent to the concentrate chamber 3113. The dilute chambers 3114 are separated from the adjacent concentrate chambers 3113 by an anionic membrane or a cation membrane. The dilute chambers 3114 are connected to the dilute water outlet and the high sugar solution feed port, respectively, and the concentrate chambers 3113 are connected to the concentrate water outlet. Here, the anionic membrane or the cation membrane is an alloy membrane.

[0055] Preferably, the number of electrodialyzers is greater than or equal to 3. When there are three electrodialyzers, they are a first electrodialyzer 311, a second electrodialyzer 312, and a third electrodialyzer 313. Here, the electrodialysis desalination device 3 further includes a desalted water storage tank 32, a fresh water temporary storage tank 33, and a concentrated water temporary storage tank 34.

[0056] The first electrodialyzer 311 is connected to the second electrodialyzer 312, and a first-stage electrodialysis unit is formed between the first electrodialyzer 311 and the second electrodialyzer 312; the second electrodialyzer 312 is connected to the desalted water storage tank 32, and a second-stage electrodialysis unit is formed between the desalted water storage tank 32 and the electrodialyzer 312; the second electrodialyzer 312 is connected to the third electrodialyzer 313, and the third electrodialyzer 3123 is connected to the desalted water storage tank 32, and a third-stage electrodialysis unit is formed between the desalted water storage tank 32 and the third electrodialyzer 313.

[0057] The feed port of the first electrodialyzer 311 is connected to the high sugar solution storage tank 23, the fresh water outlet of the first electrodialyzer 311 is connected to the feed port of the second electrodialyzer 312, and the concentrated water outlet of the first electrodialyzer 311 is connected to the concentrated water storage tank 34; the concentrated water outlet of the second electrodialyzer 312 is connected to the first electrodialyzer 311, and the fresh water outlet of the second electrodialyzer 312 is connected to the feed port of the third electrodialyzer 313; the fresh water outlet of the third electrodialyzer 313 is connected to the fresh water storage tank 33, and the concentrated water outlet of the third electrodialyzer 313 is connected to the second electrodialyzer 312; the concentrated water storage tank 34 is connected to the evaporation device 4.

[0058] That is, the high sugar solution passes through the first electrodialyzer 311, the second electrodialyzer 312 and the third electrodialyzer 313 in sequence to obtain fresh water. The demineralized water passes through the third electrodialyzer 313, the second electrodialyzer 312 and the first electrodialyzer 311 in sequence to obtain concentrated water.

[0059] In one embodiment, if Figure 2 and Figure 12 As shown, the evaporation device 4 includes an MVR evaporator 41 , a concentrated liquid temporary storage tank 42 , and an evaporated condensed water temporary storage tank 43 .

[0060] Specifically, one end of the MVR evaporator 41 is connected to the concentrated water temporary storage tank 34, and the other end is connected to the concentrated liquid temporary storage tank 42 and the evaporation condensed water temporary storage tank 43. The evaporation condensed water temporary storage tank 43 is used to store the evaporated condensed water. The concentrated liquid temporary storage tank 42 is used to store the evaporated concentrated liquid. The concentrated liquid temporary storage tank 42 is connected to the high sugar liquid temporary storage tank 23. The MVR evaporator 41 concentrates the concentrated water to 45-50 refractive index. At this time, most of the salt crystals are precipitated. After the salt is separated by centrifugation, the remaining sugar solution is returned to the electrodialysis desalination device 3. Here, the processing capacity of the MVR evaporator 41 is 18-22m 3 / h, evaporation temperature 90-95℃, concentrated liquid refractive index 45-50, salt removal rate 85%-90%.

[0061] Furthermore, the evaporation device 4 also includes a centrifugal desalination unit.

[0062] In addition, each of the above-mentioned devices also includes a supporting cleaning system, including a cleaning tank, various cleaning agent addition devices and supporting pipelines.

[0063] Each delivery pipe is equipped with a flow meter, control valve and automatic control device according to actual needs.

[0064] Specifically, the working principle of the present invention is:

[0065] (1) A hydrolysis device is used to carry out a hydrolysis process, using sulfuric acid as a catalyst to hydrolyze hemicellulose into xylose under certain temperature and time conditions.

[0066] (2) A chromatographic deacidification device is used to carry out the chromatographic deacidification process. The difference in the interaction force between different solutes and the stationary phase and the mobile phase is utilized. When the two phases move relative to each other, each solute makes multiple equilibriums between the two phases, so that each solute is separated from each other, thereby achieving the separation of acid and sugar salt.

[0067] (3) A water softening device is used to perform an acid removal process, the acid liquid of the chromatographic deacidification device is discharged and softened, and the softened liquid is then fed into the chromatographic separation column of the tank body to discharge the acid liquid inside the chromatographic separation column.

[0068] (4) An electrodialysis desalination device is used for the electrodialysis desalination process. Under the action of a DC electric field, cations (sodium ions) in the fresh water chamber migrate toward the negative electrode (i.e., cathode) and can only pass through the cation membrane; anions (sulfate ions) migrate toward the positive electrode (i.e., anode) and can only pass through the anion membrane, thereby desalinating the sodium sulfate in the fresh water chamber; the sodium sulfate in the concentrated water chamber is concentrated, and the concentrated water and fresh water are respectively drawn out, thereby achieving the purpose of desalination.

[0069] (5) Using an evaporation device, after the high-sugar solution boils under steam heating, a vacuum pump pulls out the water vapor to cool and liquefy it, and a compressor compresses the low-temperature steam for a second time to increase its temperature, thereby concentrating the sugar solution and achieving secondary utilization of heat. After the sugar solution is concentrated, a large amount of sodium sulfate crystals precipitate, and a sugar solution with a lower salt content is finally obtained by centrifugation.

[0070] The beneficial effects of the utility model include:

[0071] 1) In the chromatographic deacidification device, the utility model significantly improves the height-to-diameter ratio of the ion exchange column compared to the traditional single ion exchange column divided into multiple tubular structures, thereby controlling the speed of the cellulose hydrolyzate entering the ion exchange column throughout the process and ensuring the uniformity of the flow.

[0072] 2) The utility model is provided with a spray device consisting of an annular distribution pipe and a transverse distribution pipe. On the one hand, the annular distribution pipe is connected to multiple transverse distribution pipes. When the cellulose hydrolyzate flows into the annular distribution pipe and then flows into multiple transverse distribution pipes, the cellulose hydrolyzate finally flows into multiple tube-arrayed ion exchange columns from the through holes of the transverse distribution pipes, ensuring that the flow of the cellulose hydrolyzate has only two components, parallel to the tube bundle and perpendicular to the tube bundle, further ensuring the uniformity of the flow, thereby ensuring that the performance of the ion exchange column is not affected.

[0073] 3) The utility model is provided with a softening water device, which softens and deacidifies the acid liquid of the chromatographic deacidification device in a deacidification soft tank, and then the deacidified liquid enters the soft water tank. Finally, under the action of a water pump, the liquid in the soft water tank is passed through a pipeline into the hemicellulose hydrolyzate feed port to flush the chromatographic separation column and discharge the acid liquid inside the chromatographic separation column, thereby avoiding the problem of low equipment efficiency caused by taking out the single-column ion exchange reactor column for deacidification.

[0074] 4) The present invention is provided with an ion exchange device, which is used to treat the fresh water discharged from the fresh water outlet.

[0075] 5) The present invention uses a hydrolysis device to hydrolyze alkali-containing hemicellulose, uses a chromatographic deacidification device to deacidify the cellulose hydrolyzate to obtain an acid solution and a high-sugar solution, uses an electrodialysis desalination device to perform electrodialysis desalination on the high-sugar solution to obtain concentrated water and fresh water, and uses an evaporation device to evaporate the concentrated water to obtain xylose. Compared with the prior art that adds salt and / or acid, the present invention uses a chromatographic deacidification device to remove acid, an electrodialysis desalination device to desalinate, and an evaporation device to concentrate and desalinate to recover xylose, thereby increasing the yield of xylose, with a yield of greater than 98%.

[0076] 6) The utility model uses a chromatographic deacidification device and an electrodialysis desalination device for classified recovery, and the yield of xylose and acid can reach 98%, basically achieving zero emission, which can make resources recycled and reused, reduce the COD content in sewage, and effectively reduce environmental pressure. For example, wastewater discharge is reduced by about 3,000 tons / day, and sewage treatment fees are saved by about 20 yuan / ton.

[0077] 7) The utility model removes salt and acid through a chromatographic deacidification device and electrodialysis desalination, has high controllability, effectively avoids the introduction of new impurities, reduces costs, and increases profits by approximately RMB 50,000 per day.

[0078] 8) In the present invention, since most of the lost sugar is recovered, the service life of various devices is greatly increased (for example, the service life of the anion membrane or cation membrane is increased by more than 30%), which not only increases the stability of the xylose preparation process, but also improves the usability of the equipment and reduces the cost of equipment consumption.

[0079] This document uses specific examples to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the technical solutions and core ideas of the present application. Ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some of the technical features therein with equivalents; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An apparatus for recovering acid and xylose from alkali-containing hemicellulose, comprising a hydrolysis unit, a chromatographic deacidification unit, an electrodialysis desalination unit, and an evaporation unit, wherein the chromatographic deacidification unit comprises a tank, a chromatographic separation column, a hemicellulose hydrolyzate feed port, and an acid outlet, and is characterized in that: The chromatographic separation columns of the chromatographic deacidification device are multiple parallel arranged tubular structures, and a spray unit is provided between the hemicellulose hydrolyzate feed port and the chromatographic separation columns; the equipment also includes a softening device, and the acid outlet of the chromatographic deacidification device is connected to the softening device.

2. The device according to claim 1, characterized in that The softening device is provided with a deacidification water tank, a softening water tank, a softening water pump and a pipeline; the deacidification water tank is provided with an acid inlet and an acid outlet, the acid inlet of the deacidification water tank is connected to the acid outlet of the chromatographic deacidification device, the acid outlet of the deacidification water tank is connected to the softening water tank, one end of the pipeline is connected to the softening water tank through the softening water pump, and the other end is connected to the hemicellulose hydrolyzate feed port.

3. The device according to claim 1, characterized in that The spray unit includes an annular distribution pipe, which is connected to the hemicellulose hydrolyzate feed port. The inner side of the annular distribution pipe is connected to several transverse distribution pipes connected to the annular distribution pipe. Through holes for liquid to flow into multiple tubular structures are provided below the transverse distribution pipes.

4. The device according to claim 1, characterized in that An upper tube distribution plate and a lower tube distribution plate are provided in the tank body, and the chromatographic separation column is installed between the upper and lower tube distribution plates.

5. The device according to claim 4, characterized in that The tank body includes an upper cylinder, a middle cylinder and a lower cylinder which are connected in sequence. The upper tube distribution plate is installed between the upper cylinder and the middle cylinder, and the lower tube distribution plate is installed between the middle cylinder and the lower cylinder.

6. The device according to claim 5, characterized in that The lower cylinder is conical, and an acid liquid discharge port and a high sugar liquid discharge port are provided at the lower part.

7. The device according to claim 1, characterized in that The hydrolysis device is provided with a hydrolysis kettle, one end of which is connected to a discharge port of hemicellulose hydrolyzate, and the other end is connected to a feed port of alkali-containing hemicellulose raw material.

8. The device according to claim 1, characterized in that The electrodialysis desalination device is provided with a high-sugar solution feed port, an electrodialysis unit, a fresh water discharge port and a concentrated water discharge port. One end of the electrodialysis unit is connected to the high-sugar solution feed port, and the other end is connected to the fresh water discharge port and the concentrated water discharge port respectively; the concentrated water discharge port is connected to the evaporation device, and the fresh water discharge port is connected to the external discharge channel.

9. The device according to claim 8, characterized in that The electrodialysis unit comprises at least one electrodialyser.

10. The device according to claim 8, characterized in that The equipment further comprises an ion exchange device, and the fresh water outlet of the electrodialysis desalination device is connected to the ion exchange device through an external discharge channel.

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