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CN-121992156-A - Energy-saving xylose production process

CN121992156ACN 121992156 ACN121992156 ACN 121992156ACN-121992156-A

Abstract

The invention provides an energy-saving xylose production process which comprises the steps of corncob crushing, hydrolysis, active carbon decoloring, decarbonizing, high-pressure membrane concentration, calcium adding and neutralization, carbon saturation reaction, ion exchange, secondary membrane concentration, secondary decoloring and overpass, removing water through a three-effect or higher-efficiency evaporator, improving the sugar degree to 65%, cooling and crystallizing high-concentration liquid to generate high-purity xylose powder, drying, warehousing finished products, sealing boxes and bagging the finished products into a warehouse. The concentration process removes a large amount of organic acid, reduces the occupation of the organic acid on the resin, improves the exchange rate, concentrates all substances except the organic acid, and reduces the treatment content of the subsequent impurity removal process by neutralizing a large amount of salt after the concentration is improved.

Inventors

  • YANG DONGPING

Assignees

  • 拾海环保工程(四川)有限公司

Dates

Publication Date
20260508
Application Date
20260127

Claims (9)

  1. 1. The xylose energy-saving production process is characterized by comprising the following steps of: s1, crushing corncob; S2, performing hydrolysis; S3, decolorizing with active carbon; S4, performing carbon removal; s5, performing high-pressure membrane concentration; S6, adding calcium for neutralization; s7, performing a carbon saturation reaction; S8, performing ion exchange; S9, performing secondary membrane concentration; S10, performing secondary decolorization and interchange; S11, removing water through a triple-effect or higher-efficiency evaporator, and improving the sugar degree to 65%; s12, cooling and crystallizing the high-concentration liquid to generate high-purity xylose powder and drying the xylose powder; and S13, warehousing the finished product, sealing the box, bagging the obtained finished product, and entering a warehouse.
  2. 2. The xylose energy-saving production process according to claim 1, characterized in that said step S1 comprises in particular: The corncob crushing process includes the steps of firstly screening mildew-free dry corncobs, washing, draining, drying to reach the water content of 10% -15%, coarse crushing to 5-10mm particles by a jaw or hammer crusher, fine grinding by a universal crusher or an air flow crusher, screening by a 80-120 mesh screen, returning particles which do not reach the standard to secondary crushing, controlling the crushing temperature to be less than or equal to 60 ℃ and carrying out magnetic separation and impurity removal, and finally obtaining corncob powder with uniform particle size, so that the requirement of the subsequent hydrolysis process is met.
  3. 3. The xylose energy-saving production process according to claim 1, characterized in that said step S2 comprises in particular: the hydrolysis of corncob sulfuric acid method adopts dilute sulfuric acid with the concentration of 0.5-3% to react for 2-4 hours at the temperature of 120-130 ℃, hemicellulose is hydrolyzed into reducing sugar in a single batch or percolation mode, the yield is 32-36%, and the hydrolysate contains 5-6% of reducing sugar.
  4. 4. The xylose energy-saving production process according to claim 1, characterized in that said step S3 comprises in particular: adding activated carbon in a proportion of 0.02-0.1% into the mixture at the later stage of hydrolysis, and adsorbing residual plant colloid, namely a small part of pigment, so as to remove impurities which are easy to pollute and block a membrane for concentration; the step S4 specifically includes: filtering by adopting a closed plate filter or a ceramic membrane or a hollow fiber membrane with filter materials, and obtaining clean feed liquid completely free of any visible matters after filtering.
  5. 5. The xylose energy-saving production process according to claim 1, characterized in that said step S5 comprises in particular: Concentrating the clean liquid sugar degree in the step S4 from 6-8% to 20%, reducing the liquid volume to 1/3 of the original liquid volume, and removing 0.5% of organic acid after concentrating the clean liquid sugar degree still containing 1.5% of sulfuric acid and 1.5% of organic acid; the step S6 specifically includes: And (3) raising the conductance of the concentrated solution with 20% sugar degree generated in the step S5 to 30ms/cm, wherein a large amount of sulfuric acid and organic acid are used, and calcium oxide or calcium oxide is adopted for neutralization to remove sulfate radical, so that the conductance can be reduced to 9ms/cm, and the conductance requirement of the subsequent ion exchange feed liquor is met.
  6. 6. The xylose energy-saving production process according to claim 1, characterized in that said step S7 comprises in particular: After the production of the step S6, the solution contains about 0.05% of calcium ions, carbon dioxide is added to the solution to carry out carbon saturation reaction, and the precipitation generated in the process adsorbs part of pigments and colloids, so that pollution and calcium ion load of subsequent ion exchange are reduced.
  7. 7. The xylose energy-saving production process according to claim 1, characterized in that said step S8 comprises in particular: the purification liquid produced in the step S7 is subjected to macroporous anion resin to remove inorganic acid, organic acid and most of cations, the approximate conductance of the separated liquid can reach 300-500us/cm, and the process can involve the use of clear water to remove materials and the entry of clear water, so that the original 20% sugar degree is reduced by 10%.
  8. 8. The xylose energy-saving production process according to claim 1, characterized in that said step S9 comprises in particular: and (3) concentrating the 10% sugar degree liquid generated in the step S8 to 20% again, and concentrating the sugar degree and simultaneously increasing the concentration of the conductivity impurities to reach the concentration for ion exchange to continue removal.
  9. 9. The xylose energy-saving production process according to claim 1, characterized in that said step S10 comprises in particular: the purification liquid generated in the step S9 is subjected to macroporous anion resin for the second time to remove inorganic acid, organic acid and most of cations, the conductance of the separated liquid can reach 100us/cm, and the process involves the steps of using clear water to remove materials and cleaning water to enter the process, so that the original 20% sugar degree is reduced to 10%.

Description

Energy-saving xylose production process Technical Field The invention relates to the technical field of xylose production and membranes, in particular to a high-efficiency application process of membrane concentration in a process. Background Xylose) Is produced by utilizing hydrolysis and chain breaking of plant hemicellulose, and agricultural wastes such as corncobs, bagasse and the like are used as main raw materials in industrial production. The main flow is dilute acid hydrolysis, which is to crush the raw materials to below 5mm and hydrolyze the raw materials with 1.5% -2% sulfuric acid solution at 100-105 ℃ for 2-3 hours. Neutralizing the hydrolysate with lime, decolorizing with active carbon to remove pigment, desalting with cation/anion exchange resin to remove impurities, and reducing conductivity to below 50 μS/cm. And then concentrating by triple effect evaporation until the concentration of sugar solution is more than 80%, crystallizing to separate out white crystals, and obtaining a finished product by centrifugation and fluidized bed drying. A large amount of water is used in the conventional process, and the production cost is high. The present application proposes an energy-saving production process of xylose to solve the above problems, which cannot cope with the now intense competitive market. Disclosure of Invention The invention aims to overcome the defects of the prior art and provide an energy-saving xylose production process which can well solve the problems. In order to meet the requirements, the invention adopts the technical proposal that the xylose energy-saving production process is provided, and comprises the following steps of The xylose energy-saving production process has the following advantages: 1. the membrane concentration equipment is introduced into the production process before neutralization, so that all subsequent liquid volumes are reduced, and the scale of subsequent treatment equipment and the consumption of water are reduced. 2. The concentration process removes a large amount of organic acid, reduces the occupation of the resin by the organic acid and improves the exchange rate 3. Concentrating all substances except the organic acid, neutralizing a large amount of salt after the concentration is increased, and reducing the treatment content of the subsequent impurity removal procedure. Drawings The accompanying drawings, in which like reference numerals refer to identical or similar parts throughout the several views and which are included to provide a further understanding of the application, are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application and not to limit the application unduly. In the drawings: fig. 1 schematically shows a flow diagram of an energy-efficient xylose production process according to one embodiment of the application. Detailed Description The present application will be described in further detail with reference to the drawings and the embodiments, in order to make the objects, technical solutions and advantages of the present application more apparent. In the following description, references to "one embodiment," "an embodiment," "one example," "an example," etc., indicate that the embodiment or example so described may include a particular feature, structure, characteristic, property, element, or limitation, but every embodiment or example does not necessarily include the particular feature, structure, characteristic, property, element, or limitation. In addition, repeated use of the phrase "according to an embodiment of the application" does not necessarily refer to the same embodiment, although it may. Certain features have been left out of the following description for simplicity, which are well known to those skilled in the art. According to one embodiment of the application, there is provided an energy-saving xylose production process, as shown in fig. 1, comprising the steps of: The method comprises the steps of S1, crushing corncobs, namely screening the mildew-free dry corncobs, washing, draining, drying to a water content of 10% -15%, coarse crushing to 5-10mm particles by a jaw crusher or a hammer crusher, fine grinding by a universal crusher or an air flow crusher, screening by a 80-120 mesh screen, returning the particles which do not reach the standard to secondary crushing, controlling the crushing temperature to be less than or equal to 60 ℃ and carrying out magnetic separation and impurity removal, and finally obtaining corncob powder with uniform particle size, so that the process requirements of subsequent hydrolysis and the like are met. S2, hydrolysis, namely, hydrolysis of corncob by a sulfuric acid method can adopt dilute sulfuric acid (the concentration is 0.5% -3%) to react for 2-4 hours at 120-130 ℃, hemicellulose is hydrolyzed into reducing sugar by a single batch or percolati