A method and system for producing a modified glycerol carbon source for improving biochemical efficiency and rate in sewage treatment

Abstract

The present invention relates to the technical field of wastewater treatment, and discloses a production method and system for a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment. The modified glycerol carbon source includes glyceraldehyde, a product obtained by a catalytic oxidation process of crude glycerol; the catalytic oxidation process includes a photocatalytic reaction using a photocatalyst; the photocatalyst includes tin dioxide composited with zinc oxide. After pre-treating the crude glycerol, catalytic oxidation is carried out to generate glyceraldehyde under the action of a photocatalyst; the concentration of glyceraldehyde in the product is confirmed by ultraviolet spectrophotometry, and after reaching the standard, the modified glycerol carbon source is obtained by filtering. The production system includes: a photocatalyst production area, a photocatalytic reaction and product detection area, and a product separation and collection area. The preparation process of the modified glycerol carbon source is simple and environmentally friendly, the sewage treatment effect is obvious, the production system is intelligent and efficient, and it can also be used to produce carbon sources for biomanufacturing, with broad market prospects.

Description

Technical Field

[0001] The present invention relates to the field of sewage treatment, and in particular to a production method and system of a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment. Background Art

[0002] With the continuous development of my country's national economy, the process of industrialization and urbanization continues to advance, and a large number of rural populations have migrated to cities and towns, resulting in a continuous increase in the comprehensive water consumption in cities and towns, and the discharge of industrial wastewater and domestic sewage has also continued to grow year by year.

[0003] Adjusting the carbon-nitrogen ratio of influent water through the addition of low-cost carbon sources has become an important method for improving wastewater treatment efficiency. With the recent development of the biodiesel industry, the application of its byproduct, crude glycerol, has attracted increasing attention. Modifying crude glycerol to obtain modified glycerol carbon sources for use in municipal wastewater treatment is a key area of ​​research in crude glycerol applications.

[0004] Chinese patent application publication number CN 116969592 A discloses a composite carbon source, its preparation method, and application. The composite carbon source preparation method comprises: 1) adding acid to crude glycerol for acidification to obtain a first acidified oil and a first glycerol liquid; 2) adding an alkaline solution to the first glycerol liquid and adjusting the pH, allowing the mixture to stand for stratification, and removing the precipitate to obtain a second glycerol liquid; 3) subjecting the first acidified oil to vacuum distillation and heating to obtain a third glycerol liquid and a first residue; 4) adding water to the first residue, centrifuging, and evaporating and condensing to obtain a fourth glycerol liquid and a second residue; 5) mixing the second and fourth glycerol liquids, and adding sugars, alcohols, acids, and a denitrification promoter to obtain the composite carbon source. This composite carbon source has higher utilization and selectivity. By combining with other carbon sources, it can promote microbial growth and metabolism.

[0005] However, the preparation conditions of this composite carbon source are relatively harsh, not environmentally friendly, and the preparation process is not simple enough. Summary of the Invention

[0006] In summary, the present invention aims to provide a method and system for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment. By utilizing an environmentally friendly photocatalyst and a relatively simple process, crude glycerol is modified to produce a modified glycerol carbon source. This modified glycerol carbon source can be used in sewage treatment to improve the biochemical efficiency and rate of sewage treatment. Furthermore, the preparation process for this modified glycerol carbon source is simple and environmentally friendly, resulting in significant sewage treatment results. The production system is intelligent and efficient, and can also be used to produce a carbon source for biomanufacturing.

[0007] To achieve the above objectives, this application adopts the following technical solutions:

[0008] In a first aspect, the present application provides a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment. The method comprises: preparing a photocatalyst, a photocatalytic reaction of a crude glycerol dilution, and detecting, separating, and collecting the modified glycerol carbon source product; the photocatalyst comprises tin dioxide composited with zinc oxide; an S-type heterojunction is formed in the tin dioxide composited with zinc oxide; the photocatalytic reaction of the crude glycerol dilution comprises: obtaining glyceraldehyde from the crude glycerol dilution through a catalytic oxidation process; the photocatalytic reaction is carried out at room temperature in a weakly acidic environment with a pH of 4 to 5; and the detection of the modified glycerol carbon source product comprises: using ultraviolet spectrophotometry to measure the concentration of glyceraldehyde in the crude glycerol dilution after photocatalysis in real time.

[0009] A method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0010] The crude glycerol is diluted with distilled water, and an organic acid is added and filtered to obtain a crude glycerol dilution, and the pH of the crude glycerol dilution is adjusted to 4-5;

[0011] Then, tin dioxide compounded with zinc oxide was added to the crude glycerol dilution solution, and the solution was irradiated under a UV light source for a set time T1 while stirring at room temperature;

[0012] Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches the target range, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source.

[0013] The method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment also includes preparing tin dioxide for composite zinc oxide, comprising the following steps:

[0014] Add tin dioxide to distilled water and ultrasonically disperse it for a set time T2 under stirring. Then, add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue ultrasonically dispersing it for a set time T3.

[0015] Then, the ultrasonic wave is terminated, the product is collected by centrifugation, and the product is dried at a set temperature R1. Finally, the product is calcined at a set temperature R2 for a set time T4, and cooled to room temperature to obtain tin dioxide composite with zinc oxide.

[0016] In a second aspect, the present application provides a production system of a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment, wherein the production system comprises a photocatalyst production area, a photocatalytic reaction and product detection area, and a product separation and collection area connected in sequence.

[0017] Beneficial technical effects

[0018] The present application is different from the conventional method of preparing glyceraldehyde by catalytic oxidation of crude glycerol. Instead, it adopts the form of photocatalysis, which can selectively increase the proportion of glyceraldehyde produced by catalytic oxidation of crude glycerol under milder conditions in a more environmentally friendly manner.

[0019] The photocatalyst used in this application is tin dioxide composited with zinc oxide. By a sol-gel method, the zinc oxide generated by the reaction of zinc acetate dihydrate is composited on tin dioxide micro-nano particles in the same solution system, and then the two are more firmly combined by high-temperature calcination. An S-type heterojunction is formed in the tin dioxide composited with zinc oxide, and a special charge transfer process occurs. In a weakly acidic catalytic environment, when irradiated by ultraviolet light, the relatively useless electrons on the conduction band of tin dioxide are combined with the relatively useless holes on the valence band of zinc oxide, and the electrons with stronger reducing ability on the conduction band of zinc oxide and the holes with stronger oxidizing ability on the valence band of tin dioxide are retained, thereby achieving the separation of photogenerated electron-hole pairs with stronger redox ability at the heterojunction interface, thereby significantly improving the catalytic efficiency and selectivity, and achieving a selective increase in the ratio of crude glycerol to glyceraldehyde by catalytic oxidation under mild conditions.

[0020] The present application also provides a modified glycerol carbon source production system that combines catalyst production, photocatalytic reaction, and product separation and collection, and uses ultraviolet spectrophotometry to measure in real time the concentration of glyceraldehyde produced after catalytic oxidation of crude glycerol, thereby achieving intelligent control of the photocatalytic reaction and obtaining qualified modified glycerol carbon sources more intelligently and accurately.

[0021] The overall production process of the modified glycerol carbon source only requires adding a photocatalyst to a weakly acidic glycerol dilution solution and then stirring under ultraviolet light at room temperature. The reaction conditions are mild, and no additional heating or addition of strong acids or bases is required. It is low-carbon and environmentally friendly, and the process is simple. At the same time, the modified glycerol carbon source ensures that the concentration of glyceraldehyde is within a certain range through real-time detection, and can be intelligently controlled as needed. Therefore, it can significantly improve the biochemical efficiency and rate in sewage treatment, and can also be used to produce carbon sources for biomanufacturing, and has broad market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic flow chart of the production method of the modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment.

[0023] Figure 2 It is a schematic diagram of the composition of the production system of the modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment.

[0024] The meaning of the accompanying symbols: 1. Photocatalyst production area; 2. Photocatalytic reaction and product detection area; 3. Product separation and collection area; 4. Catalyst pretreatment room; 5. Calcination laboratory; 6. Heat dissipation port; 7. Treatment room; 8. Ultraviolet spectrophotometry detection device; 9. Sample transfer channel; 10. Liquid delivery pipeline. DETAILED DESCRIPTION

[0025] In order to make the technical problems, technical solutions, and beneficial effects to be solved by this application more clearly understood, the present application is further described in detail below with reference to the following examples. However, this should not be construed as limiting the scope of this application to the following examples. Without departing from the above-mentioned method concepts of this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0026] In this application, the terms used in this application are for the purpose of describing specific embodiments only and are not intended to be limiting of the application.

[0027] The terms “first” and “second” are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0028] Furthermore, as used in this application and the appended claims, the singular forms "for," "or," "an," "any," and "said" are intended to include the plural forms unless the context clearly indicates otherwise.

[0029] In the first aspect, the present application provides a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment, the production method of the modified glycerol carbon source comprising: preparing a photocatalyst, a photocatalytic reaction of a crude glycerol dilution, and detecting, separating and collecting the modified glycerol carbon source product; the photocatalyst comprises tin dioxide composited with zinc oxide; an S-type heterojunction is formed in the tin dioxide composited with zinc oxide; the photocatalytic reaction of the crude glycerol dilution comprises: obtaining glyceraldehyde from the crude glycerol dilution through a catalytic oxidation process; the photocatalytic reaction reacts at room temperature under a weak acid environment with a pH of 4 to 5; the detection of the modified glycerol carbon source product comprises: using ultraviolet spectrophotometry to measure in real time the concentration of glyceraldehyde in the crude glycerol dilution after photocatalysis.

[0030] A method for producing a modified glycerol carbon source for improving biochemical efficiency and rate in sewage treatment, comprising:

[0031] The crude glycerol is diluted with distilled water, and an organic acid is added and filtered to obtain a crude glycerol dilution, and the pH of the crude glycerol dilution is adjusted to 4-5;

[0032] Then, tin dioxide compounded with zinc oxide was added to the crude glycerol dilution solution, and the solution was irradiated under a UV light source for a set time T1 while stirring at room temperature;

[0033] Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches the target range, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source.

[0034] Preferably, the organic acid is one or more of formic acid, acetic acid, and oxalic acid; and the mass ratio of the crude glycerol, distilled water, organic acid, and tin dioxide of the composite zinc oxide is (50-60):(30-45):(5-10):(5-10).

[0035] Preferably, the method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment further comprises preparing tin dioxide composite with zinc oxide, comprising the following steps:

[0036] Add tin dioxide to distilled water and ultrasonically disperse it for a set time T2 under stirring. Then, add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue ultrasonically dispersing it for a set time T3.

[0037] Then, the ultrasonic wave is terminated, the product is collected by centrifugation, and the product is dried at a set temperature R1. Finally, the product is calcined at a set temperature R2 for a set time T4, and cooled to room temperature to obtain tin dioxide composite with zinc oxide.

[0038] Preferably, the set time T1 is 2 to 4 hours; the set time T2 is 1 to 2 hours; the set time T3 is 1 to 2 hours; and the set time T4 is 4 to 6 hours.

[0039] Preferably, the index range of the glyceraldehyde content M is 4.5-6%.

[0040] Preferably, the set temperature R1 is 100-120°C; the set temperature R2 is 500-600°C.

[0041] Preferably, the particle size of the tin dioxide is in the range of 30 to 300 nm; and the particle size of the zinc acetate dihydrate is in the range of 30 to 50 nm.

[0042] Preferably, in the preparation method of tin dioxide for composite zinc oxide, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is (10-20):(10-20):(10-20):(50-60).

[0043] In the second aspect, the present application provides a production system of a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment, wherein the production system comprises a photocatalyst production area 1, a photocatalytic reaction and product detection area 2, and a product separation and collection area 3 connected in sequence.

[0044] Preferably, the photocatalyst production area 1 is provided with a catalyst pre-treatment chamber 4 and a calcination laboratory 5 ; the calcination laboratory 5 is provided with a heat dissipation port 6 .

[0045] Preferably, the photocatalytic reaction and product detection area 2 is provided with a crude glycerol pretreatment chamber 7 and an ultraviolet spectrophotometric detection device 8.

[0046] Preferably, a sample transfer channel 9 is provided between the photocatalyst production area 1 and the photocatalytic reaction and product detection area 2 ; a liquid delivery pipeline 10 is provided between the photocatalytic reaction and product detection area 2 and the product separation and collection area 3 .

[0047] The sources of experimental raw materials used in the present invention are as follows:

[0048] Tin dioxide: Bohuasi Nanotechnology (Ningbo) Co., Ltd.

[0049] Zinc acetate dihydrate: Jiangsu Bosite Chemical Technology Co., Ltd.

[0050] Ethanol: Jiangsu Bosite Chemical Technology Co., Ltd.;

[0051] Distilled water: homemade;

[0052] Organic acid: Jinan Century Tongda Chemical Co., Ltd.

[0053] Crude glycerin: Shanghai Tuyi International Trading Co., Ltd.

[0054] The following will describe in detail a method and system for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment provided by the present application in combination with different examples.

[0055] Example 1:

[0056] like Figure 1 As shown, a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0057] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 1 hour under stirring. Then add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue to disperse it ultrasonically for 1 hour.

[0058] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 100°C; finally, the product is calcined at 500°C for 4 hours, cooled to room temperature, and discharged to obtain tin dioxide composite with zinc oxide;

[0059] In steps 1 and 2, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is 10:10:10:70.

[0060] 3. Dilute the crude glycerol with distilled water, add formic acid, and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 4;

[0061] 4. Then add tin dioxide compounded with zinc oxide to the crude glycerol dilution and irradiate under ultraviolet light for 2 hours while stirring;

[0062] 5. Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches 4.5%, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source;

[0063] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, formic acid, and tin dioxide of the composite zinc oxide is 55:35:5:5.

[0064] Example 2:

[0065] like Figure 1 As shown, a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0066] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 2 hours under stirring. Then add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue to disperse it ultrasonically for 2 hours.

[0067] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 120°C; finally, the product is calcined at 600°C for 6 hours, cooled to room temperature, and discharged to obtain tin dioxide composite with zinc oxide;

[0068] In steps 1 and 2, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is 20:10:10:60.

[0069] 3. Dilute the crude glycerol with distilled water, add acetic acid, and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 5;

[0070] 4. Then add tin dioxide compounded with zinc oxide to the crude glycerol dilution and irradiate under ultraviolet light for 4 hours while stirring;

[0071] 5. Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches 6%, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source;

[0072] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, acetic acid, and tin dioxide of the composite zinc oxide is 50:30:10:10.

[0073] Example 3:

[0074] like Figure 1 As shown, a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0075] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 1.5 hours under stirring. Then add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue to disperse it ultrasonically for 1.5 hours.

[0076] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 110°C; finally, the product is calcined at 550°C for 5 hours, cooled to room temperature, and discharged to obtain tin dioxide composite with zinc oxide;

[0077] In steps 1 and 2, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is 15:15:10:60.

[0078] 3. Dilute the crude glycerol with distilled water, add oxalic acid and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 4.5;

[0079] 4. Then add tin dioxide compounded with zinc oxide to the crude glycerol dilution and irradiate under ultraviolet light for 3 hours while stirring;

[0080] 5. Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches 5%, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source;

[0081] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, oxalic acid, and tin dioxide of the composite zinc oxide is 50:40:5:5.

[0082] Example 4:

[0083] like Figure 1 As shown, a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0084] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 1 hour under stirring. Then add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue to disperse it ultrasonically for 1.5 hours.

[0085] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 100°C; finally, the product is calcined at 500°C for 5 hours, cooled to room temperature, and discharged to obtain tin dioxide composite with zinc oxide;

[0086] In steps 1 and 2, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is 10:20:20:50.

[0087] 3. Dilute the crude glycerol with distilled water, add oxalic acid and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 4;

[0088] 4. Then add tin dioxide compounded with zinc oxide to the crude glycerol dilution and irradiate under ultraviolet light for 4 hours while stirring;

[0089] 5. Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches 5.5%, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source;

[0090] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, oxalic acid, and tin dioxide of the composite zinc oxide is 50:35:5:10.

[0091] Example 5:

[0092] like Figure 1 As shown, a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0093] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 2 hours under stirring. Then add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue to disperse it ultrasonically for 1 hour.

[0094] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 100°C; finally, the product is calcined at 550°C for 5.5 hours, cooled to room temperature, and discharged to obtain tin dioxide composite with zinc oxide;

[0095] In steps 1 and 2, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is 15:10:15:60.

[0096] 3. Dilute the crude glycerol with distilled water, add formic acid, and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 4.5;

[0097] 4. Then add tin dioxide compounded with zinc oxide to the crude glycerol dilution and irradiate under ultraviolet light for 3 hours while stirring;

[0098] 5. Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches 6%, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source;

[0099] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, formic acid, and tin dioxide of the composite zinc oxide is 55:30:5:10.

[0100] Example 6:

[0101] like Figure 1 As shown, a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0102] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 2 hours under stirring. Then add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue to disperse it ultrasonically for 2 hours.

[0103] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 120°C; finally, the product is calcined at 600°C for 4 hours, cooled to room temperature, and discharged to obtain tin dioxide composite with zinc oxide;

[0104] In steps 1 and 2, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is 18:12:12:58.

[0105] 3. Dilute the crude glycerol with distilled water, add acetic acid, and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 5;

[0106] 4. Then add tin dioxide compounded with zinc oxide to the crude glycerol dilution and irradiate under ultraviolet light for 3.5 hours while stirring;

[0107] 5. Then, the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis is measured in real time by ultraviolet spectrophotometry. When the concentration M of glyceraldehyde reaches 5.5%, stirring is stopped, and the crude glycerol dilution is filtered to obtain a filtrate, which is the modified glycerol carbon source;

[0108] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, acetic acid, and tin dioxide of the composite zinc oxide is 54:30:8:8.

[0109] Figure 2 This is a schematic diagram of the components of the production system for a modified glycerol carbon source used to improve the biochemical efficiency and rate in wastewater treatment. The production system includes a photocatalyst production area 1, a photocatalytic reaction and product detection area 2, and a product separation and collection area 3, all connected in sequence. The photocatalyst production area 1 is equipped with a catalyst pretreatment chamber 4 and a calcination laboratory 5, wherein the calcination laboratory 5 is provided with a heat dissipation vent 6. The photocatalytic reaction and product detection area 2 is equipped with a crude glycerol pretreatment chamber 7 and an ultraviolet spectrophotometric detection device 8. A sample transfer channel 9 is provided between the photocatalyst production area 1 and the photocatalytic reaction and product detection area 2. A liquid delivery pipeline 10 is provided between the photocatalytic reaction and product detection area 2 and the product separation and collection area 3.

[0110] In the above examples 1 to 6, the production system of the modified glycerol carbon source is composed of Figure 2shown.

[0111] Comparative Example 1:

[0112] A method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0113] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 1 hour under stirring, and then continue to disperse it ultrasonically for 1 hour;

[0114] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 100° C.; finally, the product is calcined at 500° C. for 4 hours, cooled to room temperature, and discharged to obtain the first photocatalyst;

[0115] In steps 1 and 2, the mass ratio of tin dioxide to distilled water is 20:80.

[0116] 3. Dilute the crude glycerol with distilled water, add formic acid, and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 4;

[0117] 4. Then, add the first photocatalyst to the crude glycerol dilution and irradiate under a UV light source for 2 hours while stirring;

[0118] 5. Continue stirring for 2 hours, filter the crude glycerol dilution to obtain the filtrate, which is the modified glycerol carbon source;

[0119] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, formic acid, and the first photocatalyst is 55:35:5:5.

[0120] Comparative Example 2:

[0121] A method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0122] 1. Add the mixture of zinc acetate dihydrate and ethanol to distilled water, and ultrasonically disperse it for 1.5 hours under stirring, and then continue ultrasonically dispersing it for 1.5 hours;

[0123] 2. Then, the ultrasonic treatment was terminated, the product was collected by centrifugation, and the product was dried at 110°C; finally, the product was calcined at 550°C for 5 hours, cooled to room temperature, and discharged to obtain the second photocatalyst;

[0124] In steps 1 and 2, the mass ratio of zinc acetate dihydrate, ethanol and distilled water is 20:20:60.

[0125] 3. Dilute the crude glycerol with distilled water, add oxalic acid and filter to obtain a crude glycerol dilution, and adjust the pH of the crude glycerol dilution to 4.5;

[0126] 4. Then add the second photocatalyst to the crude glycerol dilution and irradiate under a UV light source for 3 hours while stirring;

[0127] 5. Continue stirring for 1 hour, filter the crude glycerol dilution to obtain the filtrate, which is the modified glycerol carbon source;

[0128] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, oxalic acid, and the second photocatalyst is 50:40:5:5.

[0129] Comparative Example 3:

[0130] like Figure 1 As shown, a method for producing a modified glycerol carbon source for improving the biochemical efficiency and rate in sewage treatment comprises the following steps:

[0131] 1. Add tin dioxide to distilled water and disperse it ultrasonically for 2 hours under stirring. Then add a mixture of zinc acetate dihydrate and ethanol to the distilled water and continue to disperse it ultrasonically for 2 hours.

[0132] 2. Then, the ultrasonic treatment is terminated, the product is collected by centrifugation, and the product is dried at 120°C; finally, the product is calcined at 600°C for 4 hours, cooled to room temperature, and discharged to obtain tin dioxide composite with zinc oxide;

[0133] In steps 1 and 2, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol and distilled water is 18:12:10:60.

[0134] 3. Dilute the crude glycerin with distilled water and then filter to obtain a crude glycerin dilution solution;

[0135] 4. Then add tin dioxide compounded with zinc oxide to the crude glycerol dilution and irradiate under ultraviolet light for 3.5 hours while stirring;

[0136] 5. Continue stirring for 0.5 hours, filter the crude glycerol dilution to obtain the filtrate, which is the modified glycerol carbon source;

[0137] In steps 3 to 5, the mass ratio of the crude glycerol, distilled water, and tin dioxide of the composite zinc oxide is 54:38:8.

[0138] In the above comparative examples 1 to 3, the production system composition of the modified glycerol carbon source is also as follows Figure 2 shown.

[0139] Referring to HJ / T 399-2007, the rapid digestion spectrophotometry method was used to test the chemical oxygen demand of urban domestic sewage before and after the addition of modified glycerol carbon source. The chemical oxygen demand after the addition of modified glycerol carbon source was used to evaluate the sewage treatment effect of the modified glycerol carbon source.

[0140] Table 1. Chemical oxygen demand of municipal sewage before and after adding different modified glycerol carbon sources

[0141]

[0142]

[0143] As can be seen from Table 1, the chemical oxygen demand of urban sewage is generally 300-400 mg / L; after adding the modified glycerol carbon source of Examples 1-6, the chemical oxygen demand of urban sewage is reduced to 15-30 mg / L; and after adding the modified glycerol carbon source of Comparative Examples 1-3, the chemical oxygen demand of urban sewage is still maintained at 80-140 mg / L, which is significantly higher than the modified glycerol carbon source of Examples 1-6.

[0144] This is because the modified glycerol carbon sources of Examples 1-6 were produced in a weakly acidic catalytic environment using tin dioxide composited with zinc oxide as a photocatalyst, resulting in higher catalytic selectivity. In this weakly acidic catalytic environment, when irradiated with light, photogenerated electrons in the conduction band of tin dioxide can be transferred to the conduction band of zinc oxide, while photogenerated holes in the valence band of zinc oxide can be transferred to the valence band of tin dioxide. This creates a unique electron transfer pathway, significantly improving both catalytic efficiency and selectivity, and selectively increasing the proportion of glyceraldehyde produced from the catalytic oxidation of crude glycerol under mild conditions.

[0145] In the preparation process of the modified glycerol carbon source in Comparative Examples 1 to 3, either no organic acid was added to make the catalytic environment weakly acidic, or tin dioxide composite with zinc oxide was not used as a photocatalyst. Therefore, the catalytic efficiency and selectivity were low, and the sewage treatment effect was poor.

[0146] Moreover, none of Comparative Examples 1 to 3 measured the concentration of glyceraldehyde in the crude glycerol dilution after photocatalysis in real time by ultraviolet spectrophotometry, and therefore could not achieve intelligent control of the photocatalytic reaction, nor could it obtain a qualified modified glycerol carbon source more intelligently and accurately, which is not conducive to the production of the modified glycerol carbon source.

[0147] The above results show and describe the basic principles and main features of the present invention as well as the advantages of the present invention.

[0148] Those skilled in the art will appreciate that the present invention is not limited to the foregoing embodiments. The foregoing embodiments and descriptions are merely illustrative of the principles of the present invention. Various modifications and improvements may be made to the present invention without departing from the spirit and scope of the present invention. For example, the present method or its improved methods may be used to produce raw materials for the biochemical industry. Such modifications and improvements are intended to fall within the scope of the present invention. The scope of the present invention is defined by the equivalents of the appended claims.

Claims

1. A method for producing a modified glycerol carbon source for improving biochemical efficiency and rate in sewage treatment, characterized in that: The production method of the modified glycerol carbon source includes: preparing a photocatalyst, a photocatalytic reaction of a crude glycerol dilution, and detecting, separating and collecting the modified glycerol carbon source product; the photocatalyst includes tin dioxide composited with zinc oxide; The production method of the modified glycerol carbon source specifically comprises the following steps: diluting crude glycerol with distilled water, adding an organic acid, and filtering to obtain a crude glycerol dilution, and adjusting the pH of the crude glycerol dilution to 4-5; then adding tin dioxide composited with zinc oxide to the crude glycerol dilution, and irradiating the crude glycerol dilution for a set time T1 under an ultraviolet light source while stirring at room temperature; then measuring the concentration M of glyceraldehyde in the crude glycerol dilution after photocatalysis in real time by ultraviolet spectrophotometry, stopping stirring when the glyceraldehyde concentration M reaches a target range, and filtering the crude glycerol dilution to obtain a filtrate, i.e., the modified glycerol carbon source; An S-type heterojunction is formed in the tin dioxide of the composite zinc oxide; The preparation method of the tin dioxide composite zinc oxide comprises: adding tin dioxide to distilled water, ultrasonically dispersing the tin dioxide under stirring for a set time T2, then adding a mixture of zinc acetate dihydrate and ethanol to the distilled water, adjusting the pH of the solution to a range of 1 to 3, and continuing ultrasonically dispersing the tin dioxide for a set time T3; then terminating the ultrasonication, collecting the product by centrifugation, drying the product at a set temperature R1, and finally calcining the product at a set temperature R2 for a set time T4, cooling the product to room temperature, and discharging the product to obtain the tin dioxide composite zinc oxide; The set time T1 is 2 to 4 hours; the set time T2 is 1 to 2 hours; the set time T3 is 1 to 2 hours; the set time T4 is 4 to 6 hours; the index range of the glyceraldehyde concentration M is 4.5 to 6%; the set temperature R1 is 100 to 120°C; and the set temperature R2 is 500 to 600°C.

2. The method for producing a modified glycerol carbon source for improving biochemical efficiency and rate in sewage treatment according to claim 1, characterized in that: The organic acid is one or more of formic acid, acetic acid, and oxalic acid; the mass ratio of the crude glycerol, distilled water, organic acid, and tin dioxide of the composite zinc oxide is (50-60): (30-45): (5-10): (5-10).

3. The method for producing a modified glycerol carbon source for improving biochemical efficiency and rate in sewage treatment according to claim 1, characterized in that: The particle size of the tin dioxide is in the range of 30-300 nm. In the preparation method of the tin dioxide of the composite zinc oxide, the mass ratio of tin dioxide, zinc acetate dihydrate, ethanol, and distilled water is (10-20): (10-20): (10-20): (50-60).

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