Treatment method and treatment equipment for pectin-containing wastewater

Abstract

The invention relates to a treatment method and treatment equipment for pectin-containing wastewater, and the method comprises the following steps: inputting first pectin wastewater into a biological conversion tank, and carrying out biological conversion treatment on pectin in the first pectin wastewater in the biological conversion tank based on put pectin-cellulose degradation mixed bacteria, second pectin wastewater containing small molecular structure pectin is obtained; wherein the pectin-cellulose degrading mixed bacteria are mixed flora capable of degrading pectin and cellulose at the same time, and the biological conversion treatment process is used for changing the pectin structure without influencing the chemical oxygen demand corresponding to the first pectin wastewater; inputting the second pectin wastewater into a one-stage or multi-stage anaerobic reactor for anaerobic decomposition treatment to obtain wastewater with reduced organic matter concentration after pectin catabolism and biogas; and the biogas is input to the energy supply end or the energy storage end for recycling. In the wastewater treatment period, in-situ treatment and sufficient degradation of pectin are achieved, and the treatment load and the treatment efficiency are improved.

Description

Technical Field

[0001] The present disclosure relates to the technical field of wastewater treatment, and particularly to a method and equipment for treating wastewater containing pectin. Background Art

[0002] For some enterprises such as those producing citrus canned food, producing alcohol, and primary coffee processing, wastewater containing pectin will be generated during the production process. From the perspective of environmental protection requirements, it is necessary to treat the wastewater containing pectin so that the quality of the effluent meets the standards.

[0003] Since the pectin content in the wastewater is relatively high, and pectin will cause the wastewater to be acidic, and fruit acid is generated after fermentation, resulting in a decrease in the pH value of the wastewater. Moreover, the concentration of organic matter in the wastewater containing pectin is also relatively high, which does not meet the environmental protection requirements. In related technologies, the treatment of wastewater containing pectin usually includes three stages: pretreatment, main treatment, and advanced treatment, aiming to remove pollutants such as pectin, suspended solids, and organic matter in the wastewater to ensure that the quality of the effluent meets the standards. Mostly, alkaline substances are added in the pretreatment stage to adjust the pH value of the wastewater to neutral or slightly alkaline, and then coagulants (such as polyaluminum chloride, iron salts, etc.) and flocculants (such as polyacrylamide, etc.) are added to promote the formation of larger flocs of pectin and other suspended particles, which are solidified and then filtered and separated. Then, the remaining pectin in the wastewater is subjected to subsequent treatment.

[0004] In the process of implementing the concept of the present disclosure, the inventors found that there are at least the following technical problems in the related technologies: In the traditional treatment scheme, in the pretreatment stage, the pectin in the wastewater is solidified into larger solidified substances by flocculation. This solidified substance is separated out in the subsequent treatment process. Therefore, in the subsequent wastewater treatment stage, the residual pectin (low-concentration pectin wastewater) after removing the main pectin solidified substance is treated. Although the subsequent treatment link can treat the residual pectin, since the solidified pectin in the early stage is only separated out and the treatment of the separated pectin is not realized, in fact, the sludge corresponding to this part of the separated pectin faces the problems of large accumulation amount, difficult degradation, and very low degradation efficiency (that is, the required time for degradation is very long). Summary of the Invention

[0005] In order to solve the above technical problems or at least partially solve the above technical problems, embodiments of the present disclosure provide a method and equipment for treating wastewater containing pectin.

[0006] In a first aspect, an embodiment of the present disclosure provides a method for treating pectin-containing wastewater. The above method includes: inputting the first pectin wastewater into a bioconversion tank, and based on the pectin-cellulose degrading mixed bacteria put in the bioconversion tank, performing bioconversion treatment on the pectin in the first pectin wastewater to obtain a second pectin wastewater containing pectin with a small molecular structure; wherein, the pectin-cellulose degrading mixed bacteria is a mixed bacterial population capable of degrading pectin and cellulose simultaneously, and the bioconversion treatment process is used to change the pectin structure without affecting the chemical oxygen demand (COD) corresponding to the first pectin wastewater; inputting the second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment to obtain wastewater with a reduced concentration of organic matter after pectin decomposition and biogas; the biogas is used to be input into an energy supply end or an energy storage end for recycling.

[0007] In some embodiments, the pectin-cellulose degrading mixed bacteria are obtained by the following method:

[0008] Taking Phanerochaete chrysosporium and Bacillus licheniformis as the main inoculating bacteria, performing in-situ cultivation in a strain incubator, the cultivation environment of the strain incubator is the production environment corresponding to the first pectin wastewater, cultivating to obtain the pectin-cellulose degrading mixed bacteria and continuously adding them into the bioconversion tank; or,

[0009] Taking Phanerochaete chrysosporium and Bacillus licheniformis as the main inoculating bacteria, cultivating in a laboratory based on the first pectin wastewater collected from the production environment as the cultivation environment to obtain the pectin-cellulose degrading mixed bacteria and adding them into the bioconversion tank.

[0010] In some embodiments, a regulating tank is further provided before the bioconversion tank, and the first pectin wastewater is introduced into the regulating tank and output to the bioconversion tank after flow regulation. Among them, a target chemical agent is also put in the regulating tank, and the target chemical agent contains a variety of functional components: a first functional component for promoting the growth of microorganisms and meeting the required nutrient elements during biochemical treatment, and a second functional component for promoting the suspension of pectin, preventing the aggregation of pectin, and reducing the clustering phenomenon of the pectin-cellulose degrading mixed bacteria during bioconversion treatment; wherein, the target chemical agent is synchronously input into the bioconversion tank along with the output of the first pectin wastewater.

[0011] In some embodiments, the first functional component includes at least one nutrient element of nitrogen, phosphorus, potassium, calcium, magnesium, zinc, copper, and manganese in a liquid ionic state; the second functional component includes: an amphoteric surfactant.

[0012] In some embodiments, the amphoteric surfactant is sodium amine ether carboxylate or potassium amine ether carboxylate, and the corresponding molecular formulas are respectively: NH2-Rm -(OCH2CH2)n-COONa or NH2-R m -(OCH2CH2)n-COOK, where m ranges from 10 to 18 and n ranges from 2 to 10. The preparation method of the above amphoteric surfactant is as follows: Using natural oil as the raw material, saponify the above raw material with an aqueous solution of sodium hydroxide or potassium hydroxide to obtain the corresponding fatty acid organic soap; there are carboxyl anion groups in the above fatty acid organic soap; by means of quaternization reaction, introduce cationic groups into the above fatty acid organic soap molecules to form a primary amphoteric surfactant; connect a preset number of ethoxy functional groups at the anion group of the above primary amphoteric surfactant to synthesize the above amphoteric surfactant.

[0013] In some embodiments, the above method further includes one of the following: performing ultrasonic treatment after performing biological conversion treatment in the biological conversion tank for a preset duration; or, connecting a physical conversion tank after the above biological conversion tank, and the second pectin wastewater obtained after being treated by the above biological conversion tank enters the above physical conversion tank for ultrasonic treatment. Among them, inputting the above second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment includes: performing ultrasonic treatment on the above second pectin wastewater and then inputting it into one or more anaerobic reactors for anaerobic decomposition treatment.

[0014] In some embodiments, an aeration tank is further provided after one or more anaerobic reactors; the wastewater with a reduced organic matter concentration after being treated by the above anaerobic reactor continues to be subjected to aerobic treatment through the above aeration tank to obtain target wastewater with a further reduced organic matter concentration; among them, monitor the organic matter content indexes after being treated by the above anaerobic reactor and the above aeration tank respectively; when the above organic matter content indexes meet the preset requirements, discharge or recycle the qualified wastewater.

[0015] In some embodiments, the above first pectin wastewater is high-concentration pectin wastewater, and the pectin concentration entering the above biological conversion tank is 1000 mg / L to 3000 mg / L. The above method further includes: inputting the fourth pectin wastewater remaining after partially solidifying and filtering the third pectin wastewater together with the above second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment; the above third pectin wastewater and the above first pectin wastewater are two parts obtained after the high-concentration wastewater is branched; the above fourth pectin wastewater is low-concentration pectin wastewater, and the corresponding pectin concentration is 50 mg / L to 100 mg / L; or, inputting the above second pectin wastewater into a single anaerobic reactor for anaerobic decomposition treatment, and after treatment, mixing it with the fourth pectin wastewater and then inputting it into the subsequent multi-stage anaerobic reactors for anaerobic decomposition treatment.

[0016] Second aspect, embodiments of the present disclosure provide a treatment device for pectin-containing wastewater. The above device includes: a biological conversion tank, and one-stage or multi-stage anaerobic reactors. The above biological conversion tank is used to input the first pectin wastewater, and based on the pectin-cellulose degrading mixed bacteria put in, biologically convert the pectin in the above first pectin wastewater to obtain the second pectin wastewater containing pectin with a small molecular structure; wherein, the above pectin-cellulose degrading mixed bacteria is a mixed bacterial community capable of degrading pectin and cellulose simultaneously, and the above biological conversion process is used to change the pectin structure without affecting the chemical oxygen demand corresponding to the above first pectin wastewater. The above second pectin wastewater is input into one-stage or multi-stage anaerobic reactors for anaerobic decomposition treatment to obtain wastewater with a reduced concentration of organic matter after pectin decomposition metabolism and biogas; the above biogas is used to be input into an energy supply end or an energy storage end for recycling.

[0017] In some embodiments, the above device further includes at least one of the following: a strain incubator, an adjustment tank, and an aeration tank. The above strain incubator has a wastewater interface and a strain outlet; wherein, the above wastewater interface is used to access the above first pectin wastewater as a culture environment, and Phanerochaete chrysosporium and Bacillus licheniformis are used as the main inoculated strains, and the above pectin-cellulose degrading mixed bacteria are in-situ cultured in the above strain incubator; the above strain outlet is connected to the above biological conversion tank, and the cultured above pectin-cellulose degrading mixed bacteria are continuously added to the above biological conversion tank. The above adjustment tank has a wastewater inlet and a wastewater outlet, the above wastewater inlet is used to introduce the above first pectin wastewater into the above adjustment tank, and after flow adjustment through the above adjustment tank, the above first pectin wastewater is output to the above biological conversion tank through the above wastewater outlet. A target chemical agent is also put in the above adjustment tank, and the above target chemical agent contains a variety of functional components: a first functional component for promoting the growth of microorganisms and meeting the required nutrient elements during biochemical treatment, and a second functional component for promoting pectin suspension, preventing pectin aggregation, and reducing the agglomeration phenomenon of the above pectin-cellulose degrading mixed bacteria during biological conversion treatment; wherein, the above target chemical agent is synchronously input into the above biological conversion tank along with the output of the above first pectin wastewater. The above aeration tank is connected to the outlet of the one-stage or multi-stage anaerobic reactors, and is used to continue aerobic treatment of the wastewater with a reduced concentration of organic matter after being treated by the above anaerobic reactors to obtain target wastewater with a further reduced concentration of organic matter.

[0018] In some embodiments, the above bioconversion tank is integrated with an ultrasonic function, and ultrasonic treatment is performed after the bioconversion treatment in the bioconversion tank for a preset duration; or, a physical conversion tank is connected after the above bioconversion tank, and the second pectin wastewater obtained after being treated in the above bioconversion tank enters the above physical conversion tank for ultrasonic treatment; wherein, inputting the above second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment includes: performing ultrasonic treatment on the above second pectin wastewater and then inputting it into one or more anaerobic reactors for anaerobic decomposition treatment.

[0019] In some embodiments, an input port for low-concentration pectin wastewater is further provided in the one or more anaerobic reactors, and the above input port is used to input the fourth pectin wastewater. The above fourth pectin wastewater is obtained after partial pectin solidification and filtration of the third pectin wastewater. The above third pectin wastewater and the above first pectin wastewater are two parts obtained after the high-concentration wastewater is split; the above fourth pectin wastewater is low-concentration pectin wastewater, and the corresponding pectin concentration is 50 mg / L to 100 mg / L. Among them, the above fourth pectin wastewater and the above second pectin wastewater are input into the one or more anaerobic reactors together for anaerobic decomposition treatment; or, the above second pectin wastewater is input into a first-stage anaerobic reactor for anaerobic decomposition treatment, and after treatment, it is mixed with the fourth pectin wastewater and then input into the subsequent multi-stage anaerobic reactors for anaerobic decomposition treatment.

[0020] In some embodiments, the wastewater inlet of the above treatment device is used to connect with the wastewater discharge port of the production device, and the above production device is used to produce or process one or more of citrus cans, alcohol, and coffee; the energy supply end or energy storage end is used to provide energy or store energy for the above production device.

[0021] Some or all of the above technical solutions provided by the embodiments of the present disclosure have at least the following advantages:

[0022] (1)A solution for in-situ and highly efficient treatment of pectin in wastewater is provided. During wastewater treatment, the pectin-cellulose degrading mixed bacteria put in the biological conversion tank first process the refractory macromolecular pectin into easily degradable small-molecule structured pectin. This process destroys the composition structure of pectin and has no impact on the chemical oxygen demand (COD) concentration. Then, based on one-stage or multi-stage anaerobic reactors, the dispersed pectin small molecules are further anaerobically treated to obtain wastewater with a reduced concentration of organic matter after pectin decomposition metabolism and biogas that can be input into the energy supply end or energy storage end for recycling and utilization. Based on the complex enzyme system (such as laccase, lignin peroxidase, manganese peroxidase, pectin methyl esterase, pectin lyase, pectinase, pectin depolymerase, cellulase, etc.) secreted by the pectin-cellulose degrading mixed bacteria in the liquid phase environment, the polymerization degree of complex organic matters such as pectin and cellulose in the wastewater can be reduced and the solubility can be increased. The soluble pectin is then hydrolyzed into pectic acid by pectin methyl esterase, and finally hydrolyzed into galacturonic acid by polygalacturonase, which can be utilized by various microorganisms. Therefore, based on the pectin-cellulose degrading mixed bacteria in the wastewater, the refractory pectin is processed into small-molecule structures, which can greatly improve the efficiency of subsequent anaerobic treatment, making the treatment load become 5 times the original. At the same time, it also enables the in-situ treatment and relatively complete degradation of pectin during wastewater treatment, without the operation of adjusting the PH value and avoiding the related problems of sludge treatment corresponding to the flocculated and solidified pectin during in-situ degradation.

[0023] (2)In some embodiments, the pectin-cellulose degrading mixed bacteria are mixed bacteria obtained by in-situ culturing with Phanerochaete chrysosporium and Bacillus licheniformis as the main inoculated bacteria in a production environment (such as in wastewater containing a high concentration of pectin), and are continuously added to the biological conversion tank. Since the above in-situ culturing method is based on the bacterial species cultured in a pectin-containing wastewater environment, it can be adapted to the wastewater treatment environment and continuously generated and utilized in the production environment. The pectin-cellulose degrading mixed bacteria have good environmental adaptability to the wastewater to be treated. Compared with the externally introduced bacterial species, it can effectively avoid problems such as contamination caused during the transfer or transplantation of bacterial species or the loss of performance or inactivation of bacterial species in wastewater treatment due to differences in the bacterial species culture or storage environment.

[0024] (3) In some embodiments, Phanerochaete chrysosporium and Bacillus licheniformis are used as the main inoculated bacteria, and a pectin-cellulose degrading mixed bacteria is obtained through laboratory culture and then added to the bioconversion tank. In the laboratory culture method, the wastewater from the production environment is collected as the culture environment for cultivation. The obtained pectin-cellulose degrading mixed bacteria has good environmental adaptability to the wastewater to be treated. Moreover, culturing and preserving the bacteria under appropriate conditions helps other manufacturers to promote the large-scale use for adapting to environmental wastewater treatment. That is, when treating the wastewater of a certain environment, the wastewater sampling in this environment can be used as the actual culture environment for culturing the strains of the mixed bacteria.

[0025] (4) In some embodiments, a target chemical agent is added to the adjustment tank. This target chemical agent has three functions: The first function is to provide nutrients for the pectin-cellulose degrading mixed bacteria added to the subsequent bioconversion tank, such as providing nutrient elements required for the growth and enzyme production of microorganisms, such as nitrogen, phosphorus, potassium, calcium, magnesium, zinc, copper, manganese, etc., to promote the growth and survival of the mixed bacteria without affecting the subsequent anaerobic treatment process. Moreover, the nutrients added at one time can also be continuously utilized in the subsequent biochemical treatment stage (such as the stage of bioconversion treatment by the pectin-cellulose degrading mixed bacteria, the stage of anaerobic treatment in the first-stage or multi-stage anaerobic reactor, etc.). The second function is to make the suspension performance of pectin better, not easy to precipitate and prevent coalescence. In this way, pectin is in a suspended state and not easy to coalesce in the adjustment tank and after entering the subsequent bioconversion tank, ensuring sufficient contact between pectin and the strains in the pectin-cellulose degrading mixed bacteria in the bioconversion tank and improving the treatment efficiency of the dispersed treatment of the pectin structure. The third function is that after the target chemical agent flows into the bioconversion tank with the wastewater, it can also reduce the phenomenon of biological aggregation of the pectin-cellulose degrading mixed bacteria in the bioconversion process; thus effectively reducing the adverse impact of biological aggregation on the wastewater treatment effect. Therefore, based on the target chemical agent, the treatment efficiency and stability of the pectin-containing wastewater can be comprehensively improved.

[0026] (5) Ultrasonic treatment is carried out after the bioconversion treatment in the bioconversion tank for a preset duration; or, a physical conversion tank is connected after the above bioconversion tank, and the second pectin wastewater obtained after being treated by the above bioconversion tank enters the above physical conversion tank for ultrasonic treatment; the above ultrasonic treatment is used to change the pectin structure so that the molecular chain of pectin is further broken up to obtain a smaller pectin molecular structure, and at the same time, it can also break up the pectin-cellulose degrading mixed bacteria aggregated during the bioconversion treatment, promoting the full contact between pectin molecules and the strains, thereby improving the treatment efficiency of the pectin-containing wastewater. Description of the Drawings

[0027] The accompanying drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with the present disclosure, and are used together with the specification to explain the principles of the present disclosure.

[0028] To more clearly illustrate the technical solutions in the embodiments of the present disclosure or in the prior art, the following will briefly introduce the accompanying drawings required for use in the description of the embodiments or the related art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0029] Figure 1 Schematically shown is a process schematic diagram of a pectin-containing wastewater treatment device and a corresponding treatment method according to an embodiment of the present disclosure.

[0030] Figure 2 Schematically shown is a process schematic diagram of a pectin-containing wastewater treatment device and a corresponding treatment method according to another embodiment of the present disclosure.

[0031] Figure 3 Schematically shown is a process schematic diagram of a pectin-containing wastewater treatment device and a corresponding treatment method according to still another embodiment of the present disclosure.

[0032] Figure 4 Schematically shown is a process schematic diagram of a pectin-containing wastewater treatment device and its treatment method for supporting in-situ cultivation of mixed bacteria according to an embodiment of the present disclosure. Detailed Embodiments

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present disclosure clearer, the following will clearly and completely describe the technical solutions in the embodiments of the present disclosure with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are some, but not all, of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present disclosure without creative efforts fall within the scope of protection of the present disclosure.

[0034] In the research and development, it is found that the technical route of the related technology for wastewater treatment is to solidify pectin through a flocculation method, and then treat the remaining pectin in the wastewater after filtering out the solidified pectin. In this technical route, since the solidified pectin in the early stage is only separated, in fact, the sludge corresponding to this part of the separated pectin faces the problems of large accumulation volume, difficult degradation, and very low degradation efficiency. The subsequent treatment means for the remaining pectin in the wastewater (such as anaerobic treatment or aerobic treatment, etc.) are for low-concentration pectin wastewater. If the related treatment means are directly applied to the treatment of high-concentration pectin wastewater, there will be defects such as a very long treatment cycle and poor treatment effect.

[0035] In view of this, embodiments of the present disclosure provide a method and a treatment device for treating wastewater containing pectin. During wastewater treatment, the refractory pectin is first dispersed into easily degradable small molecular structures. In this process, the composition structure of pectin is destroyed, and the corresponding COD concentration does not change. Then, the idea of continuing anaerobic treatment for the dispersed pectin small molecules is adopted. Since the refractory pectin in the wastewater is first dispersed into small molecular structures, it can not only improve the efficiency of subsequent anaerobic treatment, making the treatment load become 5 times the original; at the same time, it also enables in-situ treatment and relatively complete degradation of pectin during wastewater treatment, without the need for pH adjustment operations and avoiding the related problems of sludge treatment for the flocculated and solidified pectin during in-situ degradation.

[0036] The embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0037] The first exemplary embodiment of the present disclosure provides a method for treating wastewater containing pectin.

[0038] Figure 1 The process schematic diagram of the treatment device for wastewater containing pectin and the corresponding treatment method according to an embodiment of the present disclosure is schematically shown.

[0039] Referring to Figure 1 As shown, the method for treating wastewater containing pectin provided by the embodiments of the present disclosure includes the following steps: S110 and S120.

[0040] In step S110, the first pectin wastewater is input into the biotransformation tank, and in the above biotransformation tank, based on the pectin-cellulose degrading mixed bacteria put in, the pectin in the above first pectin wastewater is biotransformed to obtain the second pectin wastewater containing small molecular structure pectin.

[0041] For example, Figure 1 shows a treatment device including a biotransformation tank 110 and an anaerobic reactor 120, and Figure 1 also uses a dashed box to indicate the production equipment. The wastewater inlet of the above treatment device is used to connect with the wastewater discharge port of the above production equipment, and the above production equipment is used to produce or process one or more of citrus cans, alcohol, coffee, etc.

[0042] In some embodiments, the above first pectin wastewater is high-concentration pectin wastewater, and the pectin concentration entering the above biotransformation tank is 1000 mg / L to 3000 mg / L, including the end values. In one embodiment, after testing, the pectin concentration in the first pectin wastewater entering the biotransformation tank is 2000 mg / L.

[0043] In some embodiments, the operating temperature of the above biotransformation treatment is 30°C to 45°C, including the end values. For example, 35°C is adopted in this embodiment.

[0044] In the embodiments of the present disclosure, the above-mentioned pectin-cellulose degrading mixed bacteria are a mixed bacterial community capable of degrading pectin and cellulose simultaneously. The above-mentioned pectin-cellulose degrading mixed bacteria are in-situ cultured during the wastewater degradation, or are cultured in the laboratory using the wastewater in the production environment as the culture environment.

[0045] Figure 4 Schematically shown is a process schematic diagram of a treatment device and its treatment method for pectin-containing wastewater supporting in-situ culture of mixed bacteria according to an embodiment of the present disclosure.

[0046] For example, in some embodiments, as shown by the solid-line box in Figure 4 The above-mentioned treatment device further includes a strain incubator. The above-mentioned pectin-cellulose degrading mixed bacteria are obtained by the following method: taking Phanerochaete chrysosporium and Bacillus licheniformis as the main inoculated bacteria, and in-situ culturing in the strain incubator 410, the culture environment of the above-mentioned strain incubator 410 is the production environment corresponding to the above-mentioned first pectin wastewater, culturing to obtain the above-mentioned pectin-cellulose degrading mixed bacteria and continuously adding them to the above-mentioned bioconversion tank 110.

[0047] In this embodiment, taking Phanerochaete chrysosporium and Bacillus licheniformis as the main inoculated bacteria, the pectin-cellulose degrading mixed bacteria capable of degrading pectin and cellulose simultaneously are in-situ cultured in the production environment (for example, cultured in wastewater containing high-concentration pectin), and continuously added to the bioconversion tank; since the above-mentioned in-situ culture method is based on the strain cultured in the pectin-containing wastewater environment, it can be adapted to the wastewater treatment environment and continuously generated and utilized in the production environment. The pectin-cellulose degrading mixed bacteria have good environmental adaptability to the wastewater to be treated; compared with the externally introduced strains, it can effectively avoid problems such as contamination caused during the transfer or transplantation of the strains or the loss of performance or inactivation of the strains in wastewater treatment due to differences in the strain culture or storage environment.

[0048] In other embodiments, the above-mentioned pectin-cellulose degrading mixed bacteria are obtained by the following method: taking Phanerochaete chrysosporium and Bacillus licheniformis as the main inoculated bacteria, and culturing in the laboratory based on the first pectin wastewater collected from the production environment as the culture environment, obtaining the above-mentioned pectin-cellulose degrading mixed bacteria and adding them to the above-mentioned bioconversion tank.

[0049] In this embodiment, Phanerochaete chrysosporium and Bacillus licheniformis are used as the main inoculated bacteria, and a pectin-cellulose degrading mixed bacteria is obtained through laboratory culture and then added to the biotransformation pool. In the laboratory culture method, the wastewater from the production environment is collected as the culture environment for cultivation. The obtained pectin-cellulose degrading mixed bacteria has good environmental adaptability to the wastewater to be treated. Moreover, culturing and preserving the bacteria under suitable conditions helps other manufacturers to promote the large-scale use of the bacteria for treating wastewater in the adapted environment, that is, when treating the wastewater in a certain environment, the wastewater sampling in this environment can be used as the actual culture environment for culturing the mixed bacteria.

[0050] In the above two embodiments, by utilizing the difference in the culture conditions (dissolved oxygen) of Phanerochaete chrysosporium and Bacillus licheniformis, two levels of aeration parameters are set. For example, one level is high-frequency aeration with an aeration duration of 6 hours, and the other level is medium-frequency aeration with an aeration duration of 18 hours. After 5 - 8 days, the two microorganisms in the culture system can coexist stably, presenting a loose mycelial sphere shape with a diameter of about 5 mm - 10 mm. When the number of mycelial spheres reaches the preset requirement, it is considered that the cultivation is completed.

[0051] The above biotransformation treatment process is used to change the pectin structure without affecting the chemical oxygen demand (COD) corresponding to the above first pectin wastewater. In some experiments, the treatment time in the biotransformation pool treatment stage is 4 - 6 hours, and the pectin decomposition rate is more than 60%.

[0052] Specifically, the above biotransformation treatment process degrades complex macromolecules such as pectin and cellulose in the high-concentration pectin wastewater into small molecule structures. These small molecule structures are easily degraded, so that the degradation efficiency can also be improved when they are subsequently sent to one or more anaerobic reactors for anaerobic decomposition treatment. Compared with simply performing anaerobic decomposition treatment on high-concentration pectin wastewater, there is an obvious improvement in the degradation efficiency (see the effect comparison with Comparative Example 1).

[0053] In the embodiments of the present disclosure, based on the complex enzyme system (such as laccase, lignin peroxidase, manganese peroxidase, pectin methyl esterase, pectin lyase, pectinase, pectin depolymerase, cellulase, etc.) secreted by the pectin-cellulose degrading mixed bacteria in the liquid phase environment, the polymerization degree of complex organic matters such as pectin and cellulose in the wastewater can be reduced, and the solubility can be increased. The soluble pectin is then hydrolyzed into pectic acid by pectin methyl esterase, and finally hydrolyzed into galacturonic acid by polygalacturonase, which can be utilized by various microorganisms.

[0054] Based on experimental data support, the colorimetric method is used to measure the concentrations of total sugar and reducing sugar in the water sample, and the average degree of polymerization (DP) of the pectin-cellulose degradation products in the water sample is calculated. The average degree of polymerization (DP) index can reflect the structural size of polymer molecules. The larger the average degree of polymerization, the larger the corresponding molecular structure; the smaller the average degree of polymerization, the smaller the corresponding molecular structure. In step S110, the average degree of polymerization of pectin and cellulose in the influent (the first pectin wastewater, i.e., high-concentration pectin wastewater) sample of the biotransformation tank was tested to be 148.3 ± 3.6, and the average degree of polymerization of pectin and cellulose in the effluent (the second pectin wastewater) sample of the biotransformation tank was 4.7 ± 1.0, indicating that the biotransformation tank can effectively degrade the complex macromolecular pectin and cellulose in the high-concentration pectin wastewater into small-molecule structures, reducing the degree of polymerization and increasing the solubility of the macromolecular organic matter, thus helping to improve the degradation efficiency in the subsequent anaerobic treatment stage.

[0055] In step S120, the above-mentioned second pectin wastewater is input into one or more anaerobic reactors for anaerobic decomposition treatment to obtain wastewater with a reduced concentration of organic matter after pectin decomposition metabolism and biogas; the biogas is used for input to the energy supply end or energy storage end for recycling.

[0056] Chemical oxygen demand (COD) is an index to measure the concentration of organic matter. In step S110, the molecular chains of complex macromolecules such as pectin and cellulose are broken up by the pectin-cellulose degrading mixed bacteria to obtain small-molecule structures. Therefore, in the biotransformation process corresponding to step S110, the pectin structure is changed without affecting the chemical oxygen demand (COD) of the above-mentioned first pectin wastewater. Step S120 is a process based on anaerobic bacteria in the anaerobic reactor to anaerobically decompose pectin and cellulose containing a large number of easily degradable small-molecule structures, promoting the reduction of the organic matter concentration, and this stage will affect the COD.

[0057] In some embodiments, as shown in Figure 1 the above-mentioned anaerobic bacteria are put into the anaerobic reactor. The anaerobic reactor can be but is not limited to: UASB (Upflow Anaerobic Sludge Bed) anaerobic reactor, EGSB (Expanded Granular Sludge Bed) anaerobic reactor, etc. Multiple rounds of anaerobic treatment are carried out using anaerobic granular sludge + the corresponding reactor to improve the degree of reduction of the organic matter concentration. The decomposition and metabolism of pectin and cellulose are realized in the anaerobic reactor, experiencing the acidification stage, acetic acid production stage, and methane production stage.

[0058] The acidification stage refers to the stage in which soluble organic matter is converted into end products mainly composed of volatile fatty acids, also known as the fermentation stage. The vast majority of fermentative bacteria are strict anaerobes, and there are some facultative anaerobes in the anaerobic environment. These facultative anaerobes can protect strict anaerobes such as methanogens from the damage and inhibition of oxygen. The main products of this stage include volatile fatty acids, alcohols, lactic acid, carbon dioxide, hydrogen, ammonia, hydrogen sulfide, etc.

[0059] The acetogenesis stage is the stage in which the products of the acidification stage are further converted into acetic acid, hydrogen, carbonic acid, etc. The anaerobic bacteria used include hydrogen-producing acetogenic bacteria.

[0060] The methanogenesis stage is the stage in which the products of the acetogenesis stage: acetic acid, hydrogen, carbonic acid, formic acid, and methanol are converted into methane, carbon dioxide, etc.

[0061] In step S120, there may be products corresponding to multiple stages among the acidification stage, the acetogenesis stage, and the methanogenesis stage at the same time.

[0062] Refer to Figure 1 As shown, the biogas produced by the anaerobic reactor is used to be input into the energy supply end or the energy storage end for recycling. The above-mentioned energy supply end or energy storage end is connected to production equipment for producing or processing citrus canned food, alcohol, coffee, etc., to provide energy or store energy for the production equipment, so as to achieve the recycling of energy and improve environmental protection and energy utilization efficiency.

[0063] The embodiment including steps S110 to S120 provides a solution for in-situ and highly efficient treatment of pectin in wastewater. During wastewater treatment, the pectin-cellulose degrading mixed bacteria put in the biotransformation tank first process the macromolecular pectin that is difficult to degrade into small molecule-structured pectin that is easy to degrade. This process destroys the composition structure of pectin and has no impact on the concentration of chemical oxygen demand (COD). Then, based on one-stage or multi-stage anaerobic reactors, the dispersed pectin small molecules are continuously anaerobically treated to obtain wastewater with a reduced concentration of organic matter after pectin decomposition metabolism and biogas that can be input into the energy supply end or energy storage end for recycling; based on the complex enzyme system (such as laccase, lignin peroxidase, manganese peroxidase, pectin methyl esterase, pectin lyase, pectinase, pectin depolymerase, cellulase, etc.) secreted by the pectin-cellulose degrading mixed bacteria in the liquid phase environment, the polymerization degree of complex organic matters such as pectin and cellulose in the wastewater can be reduced and the solubility can be increased. The soluble pectin is hydrolyzed into pectic acid by pectin methyl esterase, and finally hydrolyzed into galacturonic acid by polygalacturonase, which can be utilized by various microorganisms; therefore, based on the pectin-cellulose degrading mixed bacteria in the wastewater, the difficult-to-degrade pectin is processed into small molecule structures, which can greatly improve the efficiency of subsequent anaerobic treatment and make the treatment load become 5 times the original; at the same time, it also enables the in-situ treatment and relatively complete degradation of pectin during wastewater treatment, without the operation of adjusting the PH value and avoiding the related problems of sludge treatment corresponding to the flocculated and solidified pectin during in-situ degradation.

[0064] Figure 2 Schematically shows a process schematic diagram of a pectin-containing wastewater treatment device and a corresponding treatment method according to another embodiment of the present disclosure.

[0065] Based on the above embodiment, it is also found that: the characteristics of the pectin-cellulose degrading mixed bacteria themselves will cause the bacteria to agglomerate during biotransformation, and after agglomeration, it will have an adverse impact on the degradation effect of pectin, cellulose, etc. At the same time, considering that the treatment method provided by the embodiment of the present disclosure is an in-situ treatment in wastewater, it provides a liquid phase environment for the growth and biotransformation of the pectin-cellulose degrading mixed bacteria, and the surface tension of the liquid phase environment, the suspension degree of particles in the liquid phase, etc. can be regulated, thereby creating a better wastewater treatment environment and helping to improve the wastewater treatment efficiency through regulation means.

[0066] In view of this, in some other embodiments of the present disclosure, the above treatment device further includes a regulating tank. Referring to Figure 2 As shown by the dotted line frame, a regulating tank 210 is provided before the above biotransformation tank 110, and the above first pectin wastewater is introduced into the above regulating tank 210 and output to the above biotransformation tank 110 after flow regulation.

[0067] The above-mentioned regulating tank 210 is also filled with a target chemical agent, and the above-mentioned target chemical agent contains a variety of functional components: a first functional component for promoting the growth of microorganisms and meeting the required nutrient elements during biochemical treatment, and a second functional component for suspending pectin, preventing pectin coalescence, and reducing the aggregation phenomenon of the above-mentioned pectin-cellulose degrading mixed bacteria during the biotransformation process; wherein, the above-mentioned target chemical agent is synchronously input into the above-mentioned biotransformation tank along with the output of the above-mentioned first pectin wastewater.

[0068] Combined Figure 2 and Figure 4 Understood in conjunction with the dashed box in, in the embodiments of the present disclosure, the above-mentioned treatment device may simultaneously include a regulating tank 210 and a strain incubator 410 for in-situ cultivation. The water inlet of the strain incubator 410 (which is the same as the wastewater interface described in the subsequent second embodiment) is connected to an outlet of the regulating tank 210 (this outlet serves as the wastewater outlet flowing to the strain incubator, and the description of the wastewater outlet can be found in the description of the regulating tank in the second embodiment). The other outlet of the regulating tank 210 (this outlet serves as the wastewater outlet flowing to the biotransformation tank, and the description of the wastewater outlet can be found in the description of the regulating tank in the second embodiment) is connected to the water inlet of the biotransformation tank 110. The pectin-cellulose degrading mixed bacteria cultured in the culture environment corresponding to the high-concentration pectin wastewater by the strain incubator 410 are continuously added to the biotransformation tank 110 based on a preset channel between the strain incubator 410 and the biotransformation tank 110. This preset channel connects the strain outlet of the strain incubator 410 and the strain injection port of the biotransformation tank 110. The above-mentioned pectin-cellulose degrading mixed bacteria are strains with a certain number of bacteria and a specific morphology generated in the culture environment, and enter the biotransformation tank along with the liquid-phase wastewater culture environment.

[0069] By adding the target chemical agent to the regulating tank, it is possible to prevent precipitation (including preventing pectin agglomeration + reducing the biological aggregation phenomenon of the mixed bacteria in the biotransformation tank during the transformation process); and it can also provide nutrients for the pectin-cellulose degrading mixed bacteria added to the subsequent biotransformation tank, thereby helping to improve the treatment efficiency and treatment stability of the wastewater. Among them, biological aggregation will affect the treatment effect of biotransformation, and at the same time, it will also affect the treatment effects of subsequent anaerobic (corresponding to one or more anaerobic reactors), anaerobic (corresponding to one or more anaerobic reactors) + aerobic (corresponding to an aeration tank) treatments.

[0070] Specifically, the target chemical agent added to the regulation pool has three functions: The first function is to provide nutrients for the pectin-cellulose degrading mixed bacteria added to the subsequent biological conversion pool, such as providing nutrient elements required for the growth and enzyme production of microorganisms, such as nitrogen, phosphorus, potassium, calcium, magnesium, zinc, copper, manganese, etc., promoting the growth and survival of the mixed bacteria without affecting the subsequent anaerobic treatment process, and the nutrients added at one time can also be continuously utilized in the subsequent biochemical treatment stage (such as the stage of biological conversion treatment by pectin-cellulose degrading mixed bacteria, the stage of anaerobic treatment in a first-stage or multi-stage anaerobic reactor, etc.); The second function is to make the suspension performance of pectin better, not easy to precipitate and prevent coalescence, so that pectin is in a suspended state and not easy to coalesce in the regulation pool and after entering the subsequent biological conversion pool, ensuring sufficient contact between pectin and the strains in the pectin-cellulose degrading mixed bacteria in the biological conversion pool, and improving the treatment efficiency of the structural dispersion treatment of pectin; The third function is that the target chemical agent can also reduce the biological aggregation phenomenon of the pectin-cellulose degrading mixed bacteria in the biological conversion process after flowing into the biological conversion pool with the wastewater; thus effectively reducing the adverse impact of biological aggregation on the wastewater treatment effect. Therefore, based on the setting of the regulation pool and the target chemical agent, the flow rate of the wastewater can be controlled, so that the wastewater can enter the biological conversion pool stably and controllably, and the suspension states of pectin, cellulose, etc. in the regulation pool can be effectively regulated. When entering the biological conversion pool, it can also simultaneously regulate the dispersion of the pectin-cellulose degrading mixed bacteria in the biological conversion pool and the suspension states of pectin, cellulose, etc., promoting sufficient contact between pectin and the strains in the pectin-cellulose degrading mixed bacteria in the biological conversion pool, thereby comprehensively improving the treatment efficiency and stability of the pectin-containing wastewater.

[0071] In some embodiments, the above-mentioned first functional component includes at least one nutrient element of nitrogen, phosphorus, potassium, calcium, magnesium, zinc, copper, and manganese in a liquid ionic state.

[0072] The above-mentioned second functional component includes: an amphoteric surfactant. By means of the above-mentioned amphoteric surfactant, the surface charge distribution and intermolecular force of the particulate matter are modified, and it has emulsifying, chelating, and dispersing functions, so that the particulate matter is always in a suspended state in the liquid phase corresponding to the wastewater.

[0073] An amphoteric surfactant is a surfactant that contains both an anionic hydrophilic group and a cationic hydrophilic group in the same molecule, and it can both donate and accept protons. By means of the second functional component, the liquid phase environment is regulated, promoting the improvement of the biological conversion treatment efficiency and contributing to the reactions in the subsequent anaerobic stage and anaerobic + aerobic stage.

[0074] In some embodiments, the above-mentioned amphoteric surfactant is sodium amine ether carboxylate or potassium amine ether carboxylate, and the corresponding molecular formulas are respectively: NH2-R m-(OCH2CH2)n-COONa or NH2-R m -(OCH2CH2)n-COOK, where m ranges from 10 to 18 and n ranges from 2 to 10. Briefly, R represents an organic group or functional group.

[0075] The preparation method of the above amphoteric surfactant is as follows:

[0076] Using natural oil as the raw material, saponify the above raw material with an aqueous solution of sodium hydroxide or potassium hydroxide to obtain the corresponding fatty acid organic soap; there are carboxyl anion groups in the above fatty acid organic soap; in some embodiments, the reaction temperature of the saponification reaction is 80°C to 100°C;

[0077] Introduce a cationic group into the above fatty acid organic soap molecule by quaternization reaction to form a primary amphoteric surfactant;

[0078] Connect a preset number of ethoxy functional groups at the anion group of the above primary amphoteric surfactant to synthesize the above amphoteric surfactant.

[0079] In some embodiments, the composition and mass ratio of the raw materials are: sodium lauramine ether carboxylate (EO3) 12%, sodium oleamine ether carboxylate (EO5) 8%, sodium gluconate 6%, citric acid 10%, disodium ethylenediaminetetraacetate 2% and water 62%.

[0080] In some embodiments, referring to Figure 2 As shown, in step S120 above, input the above second pectin wastewater into a single-stage or multi-stage anaerobic reactor for anaerobic decomposition treatment, including: subject the above second pectin wastewater to ultrasonic treatment and then input it into a single-stage or multi-stage anaerobic reactor for anaerobic decomposition treatment.

[0081] Specifically, it includes the following one:

[0082] Perform ultrasonic treatment after performing biological conversion treatment in the biological conversion tank 110 for a preset duration; referring to the dotted double arrow corresponding to the ultrasonic treatment in Figure 2 ; or,

[0083] Connect a physical conversion tank 220 after the above biological conversion tank 110, and the second pectin wastewater obtained after being treated by the above biological conversion tank 110 enters the above physical conversion tank 220 for ultrasonic treatment; referring to the dotted box corresponding to the physical conversion tank in Figure 2 .

[0084] The above ultrasonic treatment is used to change the pectin structure to disperse the molecular chains of pectin and disperse the aggregated pectin-cellulose degrading mixed bacteria.

[0085] In some cases, some of the pectin-cellulose degrading mixed bacteria should be physically retained in the biotransformation tank to ensure the biomass and subsequent enzyme production. In this case, the physical transformation tank can be constructed as an ultrasonic function added to the biotransformation tank, that is, ultrasonic treatment is carried out after the biotransformation in the biotransformation tank for a certain period of time.

[0086] In other cases, the physical transformation tank 220 can also be a separately added ultrasonic treatment tank after the biotransformation tank 110. The small molecule structure pectin, pectin-cellulose degrading mixed bacteria, target chemical agent, etc. after being treated by the biotransformation tank all flow into the ultrasonic treatment tank. In this case, the mixed bacteria obtained by in-situ growth culture can be continuously added to the biotransformation tank.

[0087] The above ultrasonic treatment can change the pectin structure, further break up the molecular chain of pectin to obtain a smaller pectin molecular structure, and at the same time can also break up the pectin-cellulose degrading mixed bacteria that agglomerate during the biotransformation process, promoting the full contact between pectin molecules and the bacterial species, thereby improving the treatment efficiency of the pectin-containing wastewater. In some embodiments, a power of 5 W (watt) is used per ton of water, and the ultrasonic treatment is carried out for 5 to 10 minutes.

[0088] Figure 3 The process schematic diagram of the pectin-containing wastewater treatment equipment and the corresponding treatment method according to another embodiment of the present disclosure is schematically shown.

[0089] In some embodiments of the present disclosure, the above treatment equipment further includes an aeration tank. As shown by the dashed box in Figure 3 After the one-stage or multi-stage anaerobic reactor 120, an aeration tank 310 is further provided; the wastewater with a reduced organic matter concentration after being treated by the above anaerobic reactor 120 is continuously subjected to aerobic treatment through the above aeration tank 310 to obtain the target wastewater with a further reduced organic matter concentration.

[0090] Among them, the organic matter content indexes after being treated by the above anaerobic reactor and the above aeration tank are monitored respectively. For example, at least one of COD and BOD (biochemical oxygen demand, referring to the amount of oxygen consumed by microorganisms in sewage to oxidize and decompose organic matter under specific conditions) can be used; when the above organic matter content indexes meet the preset requirements, the up-to-standard wastewater is discharged or recycled. Generally speaking, the treatment method provided by the embodiments of the present disclosure can directly discharge or be used for recycling the up-to-standard wastewater obtained after wastewater treatment.

[0091] In some special application scenarios, some post-treatment processes (such as disinfection, adding special-purpose substances, or being used as laboratory experimental water, production water, etc. after specific treatment) can also be attached after the anaerobic reactor or after the anaerobic reactor + aeration tank aerobic treatment process to meet the specific requirements of subsequent water recycling (such as for drinking water, irrigation water, etc.).

[0092] In some embodiments of the present disclosure, a processing path compatible with the existing production line is also provided. Referring to Figure 3 as shown by the single-dashed box and the single-dashed arrow in the figure, the above method further includes: inputting the fourth pectin wastewater remaining after partially solidifying and filtering the third pectin wastewater together with the above second pectin wastewater into an anaerobic reactor of one stage or multiple stages for anaerobic decomposition treatment.

[0093] The above third pectin wastewater and the above first pectin wastewater are two parts obtained by diverting high-concentration wastewater; the above fourth pectin wastewater is low-concentration pectin wastewater, and the corresponding pectin concentration is 50 mg / L to 100 mg / L.

[0094] Alternatively, in other embodiments, the above method further includes: inputting the above second pectin wastewater into an anaerobic reactor of one stage for anaerobic decomposition treatment, and after treatment, mixing it with the fourth pectin wastewater and then inputting it into subsequent anaerobic reactors of multiple stages for anaerobic decomposition treatment.

[0095] By providing an inlet for introducing low-concentration pectin wastewater in the anaerobic reactor 120, it can be compatible with the existing production line. In the existing production line, the process is to partially solidify and filter the high-concentration pectin wastewater and then treat the remaining pectin in the wastewater. Then, by providing the above inlet, the remaining low-concentration pectin wastewater (i.e., the fourth pectin wastewater) can be anaerobically treated synchronously with the second pectin wastewater obtained after biological conversion treatment, or anaerobically decomposed in the anaerobic reactor successively, realizing the compatibility of the new process provided in this case with the existing process and the merger of production lines. It can be modified on the existing equipment without setting up two separate production lines, saving the operation and transformation costs of the treatment equipment.

[0096] Among them, the process of pectin solidification can be various known or improved processes. As an example, by adding a coagulant (such as polyaluminum chloride, iron salt, etc.) and a flocculant (such as polyacrylamide, etc.), it promotes the formation of larger flocs of pectin and other suspended particles for solidification, facilitating subsequent separation; then, through the coagulation air flotation method, by generating microbubbles, the above flocs are combined with the bubbles and float to the water surface, and then through a slag scraping mechanism for solid-liquid separation, the solidified pectin is filtered to obtain the remaining low-concentration pectin wastewater.

[0097] The processing steps and corresponding reaction devices in the above-described various embodiments can be combined with each other or extended into new embodiments, which will not be elaborated here.

[0098] To illustrate the beneficial effects of this case, the following comparative example effect comparison was carried out.

[0099] Based on the treatment solution of biological conversion treatment + anaerobic treatment provided by the embodiments of the present disclosure, in the laboratory bench-scale test stage, 5 L of high-concentration pectin wastewater with a pectin concentration of 2600 mg / L to 3000 mg / L was input into the biological conversion tank and an anaerobic reactor with a treatment capacity of 10 L for reaction treatment. The residence time was 2 days, so that the COD concentration of the wastewater was reduced by more than 80%.

[0100] In the pilot-scale test stage, 100 m³ of high-concentration pectin wastewater with a pectin concentration of 2000 mg / L to 3000 mg / L was input into the biological conversion tank and an anaerobic reactor with a treatment capacity of 200 m³ for reaction treatment. The residence time was 2 days, so that the COD concentration of the wastewater was reduced by more than 80%.

[0101] In the large-scale production stage, 1000 m³ of high-concentration pectin wastewater with a pectin concentration of 2000 mg / L to 3000 mg / L was input into the biological conversion tank and an anaerobic reactor with a treatment capacity of 2000 m³ for reaction treatment. The residence time was 2 days, so that the COD concentration of the wastewater was reduced by more than 80%.

[0102] The solution of biological conversion treatment + ultrasonic treatment + anaerobic treatment provided by the embodiments of the present disclosure can further improve the treatment efficiency compared with the solution of biological conversion treatment + anaerobic treatment.

[0103] In the laboratory bench-scale test stage, 5 L of high-concentration pectin wastewater with a pectin concentration of 2600 mg / L to 3000 mg / L was input into the biological conversion tank to be converted into small molecular structures that are easily degradable, and after further ultrasonic treatment, it was input into an anaerobic reactor with a treatment capacity of 5 L for reaction treatment. The residence time was 1 day, so that the COD concentration of the wastewater was reduced by more than 80%.

[0104] In the pilot-scale test stage, 100 m³ of high-concentration pectin wastewater with a pectin concentration of 2000 mg / L to 3000 mg / L was input into the biological conversion tank to be converted into small molecular structures that are easily degradable, and after further ultrasonic treatment, it was input into an anaerobic reactor with a treatment capacity of 100 m³ for reaction treatment. The residence time was 1 day, so that the COD concentration of the wastewater was reduced by more than 80%.

[0105] In the large-scale production stage, 1000 m³ of high-concentration pectin wastewater with a pectin concentration of 2000 mg / L to 3000 mg / L was input into the biological conversion tank to be converted into small molecular structures that are easily degradable, and after further ultrasonic treatment, it was input into an anaerobic reactor with a treatment capacity of 1000 m³ for reaction treatment. The residence time was 1 day, so that the COD concentration of the wastewater was reduced by more than 80%.

[0106] Comparative Example 1

[0107] The treatment process adopted is as follows: 5 liters of high-concentration pectin wastewater with a pectin concentration of 2600 mg / L to 3000 mg / L is input into a 25-liter anaerobic reactor for reaction treatment. The residence time is 5 days or even longer to achieve the final treatment effect that the COD concentration of the wastewater is reduced by more than 80%.

[0108] Therefore, compared with Comparative Example 1, the solution provided by the embodiments of the present disclosure, compared with the solution for treating high-concentration pectin in wastewater (without filtration) based on the anaerobic process, due to the setting of the biological conversion tank, based on the pectin-cellulose degrading mixed bacteria, pectin, cellulose, etc. are decomposed into easily degradable small molecular structures, so that the treatment load corresponding to the subsequent anaerobic treatment becomes 5 times the original and the treatment efficiency is accelerated.

[0109] Comparative Example 2

[0110] The treatment process adopted is as follows: For high-concentration pectin wastewater with the same flow rate and concentration, solidified pectin is obtained based on the flocculation filtration method, and the time-consuming for treating the solidified pectin is 20 days or even more; the time-consuming for treating the remaining low-concentration pectin wastewater is about 2 days; the overall total duration statistically obtained is 22 days or even more.

[0111] Based on the comparison of the treatment time-consuming of the above comparative examples with the treatment time-consuming of the method for treating pectin-containing wastewater provided in this case, the present application provides a solution for in-situ and high-efficiency treatment of pectin in wastewater, which can greatly improve the wastewater treatment efficiency, and at the same time make the treatment load of anaerobic treatment become 5 times the original, improving the wastewater degradation efficiency; in-situ treatment and relatively sufficient degradation are achieved during wastewater treatment, no operation of adjusting the PH value is required, and related problems of sludge treatment corresponding to the solidified pectin after flocculation are avoided during in-situ degradation.

[0112] Based on the same technical concept, the second exemplary embodiment of the present disclosure provides a treatment device for pectin-containing wastewater.

[0113] Combined with Figures 1 to 4 As shown, the above treatment device includes: a biological conversion tank 110, and one or more anaerobic reactors 120.

[0114] The above biological conversion tank 110 is used to input the first pectin wastewater, and based on the pectin-cellulose degrading mixed bacteria put in, the pectin in the above first pectin wastewater is subjected to biological conversion treatment to obtain the second pectin wastewater containing small molecular structure pectin; wherein, the above pectin-cellulose degrading mixed bacteria is a mixed bacterial population capable of degrading pectin and cellulose at the same time, and the above biological conversion treatment process is used to change the pectin structure without affecting the chemical oxygen demand corresponding to the above first pectin wastewater.

[0115] The above-mentioned second pectin wastewater is input into an anaerobic reactor 120 with one or more stages for anaerobic decomposition treatment to obtain wastewater with a reduced concentration of organic matter after pectin decomposition metabolism and biogas; the above-mentioned biogas is used to be input into an energy supply end or an energy storage end for recycling.

[0116] In some embodiments, as shown by the dashed box in Figure 1 the wastewater inlet of the above-mentioned treatment device is used to connect with the wastewater discharge port of the production device, and the above-mentioned production device is used to produce or process one or more of citrus cans, alcohol, and coffee; the above-mentioned energy supply end or energy storage end is used to provide energy or store energy for the above-mentioned production device.

[0117] In some embodiments, as shown in combination with Figures 1 to 4 the above-mentioned treatment device further includes at least one of the following: a strain incubator 410, an adjustment tank 210, and an aeration tank 310.

[0118] The above-mentioned strain incubator 410 has a wastewater interface and a strain outlet.

[0119] The above-mentioned wastewater interface is used to connect the above-mentioned first pectin wastewater as a culture environment, and Phanerochaete chrysosporium and Bacillus licheniformis are used as the main inoculated strains, and the above-mentioned pectin-cellulose degrading mixed bacteria are in-situ cultured in the above-mentioned strain incubator.

[0120] The above-mentioned strain outlet is connected to the above-mentioned bioconversion tank 110, and the cultured above-mentioned pectin-cellulose degrading mixed bacteria are continuously added to the above-mentioned bioconversion tank. In some embodiments, the pectin-cellulose degrading mixed bacteria are continuously added to the bioconversion tank 110 based on a preset channel between the strain incubator 410 and the bioconversion tank 110. This preset channel connects the strain outlet of the strain incubator 410 and the strain feeding port of the bioconversion tank 110. The above-mentioned pectin-cellulose degrading mixed bacteria are strains with a certain number of bacteria and a specific morphology generated in a culture environment, and enter the bioconversion tank along with the liquid-phase wastewater culture environment.

[0121] The above-mentioned adjustment tank 210 has a wastewater inlet and a wastewater outlet. The above-mentioned wastewater inlet is used to introduce the above-mentioned first pectin wastewater into the above-mentioned adjustment tank, and after the flow rate is adjusted through the above-mentioned adjustment tank, the above-mentioned first pectin wastewater is output to the above-mentioned bioconversion tank 110 through the above-mentioned wastewater outlet.

[0122] A target chemical agent is also put into the above-mentioned regulating tank 210. The target chemical agent contains multiple functional components: a first functional component for promoting the growth of microorganisms and meeting the required nutrient elements during biochemical treatment, and a second functional component for promoting the suspension of pectin, preventing the coalescence of pectin, and reducing the aggregation phenomenon of the above-mentioned pectin-cellulose degrading mixed bacteria during biotransformation treatment; wherein, the target chemical agent is synchronously input into the above-mentioned biotransformation tank 110 along with the output of the above-mentioned first pectin wastewater.

[0123] Based on the settings of the regulating tank and the target chemical agent, the flow rate of the wastewater can be controlled, so that the wastewater enters the biotransformation tank stably and controllably, and effectively regulates the suspension state of pectin in the wastewater and also promotes the dispersion of pectin-cellulose degrading mixed bacteria in the biotransformation tank, thereby comprehensively improving the treatment efficiency and stability of pectin-containing wastewater.

[0124] The above-mentioned aeration tank 310 is connected to the outlet of the above-mentioned one-stage or multi-stage anaerobic reactor 120, and is used for further aerobic treatment of the wastewater with a reduced organic matter concentration after being treated by the anaerobic reactor to obtain target wastewater with a further reduced organic matter concentration.

[0125] In some embodiments, referring to Figure 2 and Figure 3 as shown, wherein, inputting the above-mentioned second pectin wastewater into a one-stage or multi-stage anaerobic reactor for anaerobic decomposition treatment includes: subjecting the above-mentioned second pectin wastewater to ultrasonic treatment and then inputting it into a one-stage or multi-stage anaerobic reactor for anaerobic decomposition treatment. The above-mentioned biotransformation tank 110 is integrated with an ultrasonic function, and ultrasonic treatment is carried out after the biotransformation treatment in the biotransformation tank for a preset duration; or, a physical transformation tank 220 is connected after the above-mentioned biotransformation tank 110, and the second pectin wastewater obtained after being treated by the biotransformation tank enters the above-mentioned physical transformation tank for ultrasonic treatment. The above-mentioned ultrasonic treatment is used to change the pectin structure to break up the molecular chains of pectin and break up the aggregated pectin-cellulose degrading mixed bacteria.

[0126] The above-mentioned ultrasonic treatment can change the pectin structure to further break up the molecular chains of pectin to obtain a smaller pectin molecular structure, and at the same time can also break up the aggregated pectin-cellulose degrading mixed bacteria during biotransformation treatment, promoting the full contact between pectin molecules and bacterial strains, thereby improving the treatment efficiency of pectin-containing wastewater.

[0127] In some embodiments, referring to Figure 3As shown, an input port for low-concentration pectin wastewater is also provided in the first-stage or multi-stage anaerobic reactor 120. The above input port is used to input the fourth pectin wastewater, and the above fourth pectin wastewater is obtained by partially solidifying and filtering the third pectin wastewater. The above third pectin wastewater and the above first pectin wastewater are two parts obtained by diverting high-concentration wastewater; the above fourth pectin wastewater is low-concentration pectin wastewater, and the corresponding pectin concentration is 50 mg / L to 100 mg / L. Among them, the above fourth pectin wastewater and the above second pectin wastewater are input into the first-stage or multi-stage anaerobic reactor together for anaerobic decomposition treatment; or, the above second pectin wastewater is input into the first-stage anaerobic reactor for anaerobic decomposition treatment, and after treatment, it is mixed with the fourth pectin wastewater and then input into the subsequent multi-stage anaerobic reactors for anaerobic decomposition treatment.

[0128] By providing an input port for introducing low-concentration pectin wastewater in the anaerobic reactor 120, it can be compatible with the existing production line. In the existing production line, the process is to partially solidify and filter high-concentration pectin wastewater and then treat the remaining pectin in the wastewater. Then, by setting the above input port, the remaining low-concentration pectin wastewater (i.e., the fourth pectin wastewater) can be anaerobically treated synchronously with the second pectin wastewater obtained after biological conversion treatment, or anaerobically decomposed in the anaerobic reactor successively, realizing the compatibility of the new process provided in this case with the existing process and the merger of production lines. It can be modified on the existing equipment without setting up two separate production lines, saving the operation and transformation costs of treatment equipment.

[0129] Other details of this embodiment can refer to the relevant description of the first embodiment and will not be elaborated here.

[0130] It should be noted that in this article, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "including a..." does not exclude the existence of additional identical elements in the process, method, article or device including the said element.

[0131] The above are only specific embodiments of the present disclosure, enabling those skilled in the art to understand or implement the present disclosure. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure will not be limited to these embodiments shown herein, but rather to the broadest scope consistent with the principles and novel features claimed herein.

Claims

1. A method for treating pectin-containing wastewater, characterized in that: include: Inputting the first pectin wastewater into a bioconversion pool, in which the pectin in the first pectin wastewater is subjected to a bioconversion treatment based on the added pectin-cellulose degrading mixed bacteria, to obtain a second pectin wastewater containing small molecular structure pectin; wherein the pectin-cellulose degrading mixed bacteria is a mixed bacterial community capable of simultaneously degrading pectin and cellulose, and the bioconversion treatment process is used to change the pectin structure without affecting the chemical oxygen demand corresponding to the first pectin wastewater; The second pectin wastewater is input into a primary or multi-stage anaerobic reactor for anaerobic decomposition treatment to obtain wastewater and biogas with reduced organic matter concentration after pectin decomposition and metabolism; the biogas is used to be input into an energy supply end or an energy storage end for recycling.

2. The method according to claim 1, characterized in that The pectin-cellulose degrading mixed bacteria are obtained in the following manner: Using Phanerochaete chrysosporium and Bacillus licheniformis as the main inoculated bacteria, in situ culturing them in a bacterial culture vessel, the culturing environment of the bacterial culture vessel being the production environment corresponding to the first pectin wastewater, culturing the pectin-cellulose degrading mixed bacteria and continuously adding them to the bioconversion tank; or, Phanerochaete chrysosporium and Bacillus licheniformis are used as the main inoculated bacteria, and are cultured in the laboratory based on the first pectin wastewater collected from the production environment as the culture environment to obtain the pectin-cellulose degrading mixed bacteria and add them into the bioconversion tank.

3. The method according to claim 1, characterized in that A regulating tank is also provided before the biological conversion tank, and the first pectin wastewater is introduced into the regulating tank and output to the biological conversion tank after flow regulation; Among them, target chemicals are also added into the regulating tank, and the target chemicals include multiple functional components: a first functional component corresponding to promoting microbial growth and satisfying the nutrients required during biochemical treatment, and a second functional component for promoting pectin suspension, preventing pectin aggregation, and reducing the agglomeration phenomenon of the pectin-cellulose degrading mixed bacteria during bioconversion treatment; wherein, the target chemicals are synchronously input into the bioconversion tank along with the output of the first pectin wastewater.

4. The method according to claim 3, characterized in that The first functional component includes: at least one nutrient element selected from nitrogen, phosphorus, potassium, calcium, magnesium, zinc, copper and manganese in liquid ionic state; The second functional component includes: an amphoteric surfactant.

5. The method according to claim 4, characterized in that The amphoteric surfactant is an amine ether carboxylic acid sodium salt or an amine ether carboxylic acid potassium salt, and the corresponding molecular formulas are: NH2-R m -(OCH2CH2)n-COONa or NH2-R m -(OCH2CH2)n-COOK, m is 10 to 18, n is 2 to 10; The preparation method of the amphoteric surfactant is as follows: Using natural oil as raw material, saponifying the raw material with sodium hydroxide or potassium hydroxide aqueous solution to obtain corresponding fatty acid organic soap; the fatty acid organic soap contains carboxyl anion groups; Using quaternization reaction, cationic groups are introduced into the fatty acid organic soap molecules to form primary amphoteric surfactants; A preset number of ethoxy functional groups are connected to the anionic group of the primary amphoteric surfactant to synthesize the amphoteric surfactant.

6. The method according to claim 1, characterized in that Also includes one of the following: After the bioconversion treatment in the bioconversion tank has been carried out for a preset period of time, ultrasonic treatment is performed; or, A physical conversion tank is connected after the biological conversion tank, and the second pectin wastewater obtained after being treated in the biological conversion tank enters the physical conversion tank for ultrasonic treatment; The step of inputting the second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment comprises: subjecting the second pectin wastewater to ultrasonic treatment and then inputting the second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment.

7. The method according to claim 1, characterized in that An aeration tank is also provided after the primary or multi-stage anaerobic reactor; The wastewater with reduced organic matter concentration treated by the anaerobic reactor is further subjected to aerobic treatment in the aeration tank to obtain target wastewater with further reduced organic matter concentration; wherein, monitoring the content index of organic matter after being treated by the anaerobic reactor and the aeration tank respectively; When the organic matter content index meets the preset requirements, the qualified wastewater will be discharged or recycled.

8. The method according to any one of claims 1 to 7, characterized in that The first pectin wastewater is high-concentration pectin wastewater, wherein the pectin concentration entering the bioconversion tank is 1000mg / L to 3000mg / L; The method further comprises: The fourth pectin wastewater remaining after partial pectin solidification and filtration of the third pectin wastewater is input into a primary or multi-stage anaerobic reactor together with the second pectin wastewater for anaerobic decomposition treatment; the third pectin wastewater and the first pectin wastewater are two parts obtained after high-concentration wastewater is diverted; the fourth pectin wastewater is low-concentration pectin wastewater, and the corresponding pectin concentration is 50mg / L to 100mg / L; or, The second pectin wastewater is input into a primary anaerobic reactor for anaerobic decomposition treatment, and after the treatment, it is mixed with the fourth pectin wastewater and then input into a subsequent multi-stage anaerobic reactor for anaerobic decomposition treatment.

9. A treatment device for pectin-containing wastewater, characterized in that: include: Bioconversion tanks, one or more anaerobic reactors; The bioconversion pool is used to input a first pectin wastewater, and the pectin in the first pectin wastewater is subjected to a bioconversion treatment based on the added pectin-cellulose degrading mixed bacteria to obtain a second pectin wastewater containing small molecular structure pectin; wherein the pectin-cellulose degrading mixed bacteria is a mixed bacterial community capable of simultaneously degrading pectin and cellulose, and the bioconversion treatment process is used to change the pectin structure without affecting the chemical oxygen demand corresponding to the first pectin wastewater; The second pectin wastewater is input into a primary or multi-stage anaerobic reactor for anaerobic decomposition treatment to obtain wastewater and biogas with reduced organic matter concentration after pectin decomposition and metabolism; the biogas is used to be input into the energy supply end or the energy storage end for recycling.

10. The device according to claim 9, characterized in that Also includes at least one of the following: a bacterial culture tank, a regulating tank, and an aeration tank; The strain culture device has a wastewater interface and a strain outlet; wherein the wastewater interface is used to access the first pectin wastewater as a culture environment, and Phanerochaete chrysosporium and Bacillus licheniformis are used as the main inoculated bacteria to obtain the pectin-cellulose degrading mixed bacteria by in-situ culture in the strain culture device; the strain outlet is connected to the bioconversion tank, and the cultured pectin-cellulose degrading mixed bacteria are continuously added to the bioconversion tank; The regulating tank has a wastewater inlet and a wastewater outlet, the wastewater inlet is used to introduce the first pectin wastewater into the regulating tank, and after flow regulation in the regulating tank, the first pectin wastewater is output to the bioconversion tank through the wastewater outlet; The regulating tank is also filled with a target chemical agent, which includes a plurality of functional components: a first functional component for promoting microbial growth and satisfying the nutrient elements required during the biochemical treatment, and a second functional component for promoting pectin suspension, preventing pectin aggregation, and reducing the agglomeration of the pectin-cellulose degrading mixed bacteria during the bioconversion treatment; wherein the target chemical agent is synchronously input into the bioconversion tank along with the output of the first pectin wastewater; The aeration tank is connected to the outlet of the primary or multi-stage anaerobic reactor, and is used to continue aerobic treatment of the wastewater with reduced organic matter concentration after treatment by the anaerobic reactor to obtain target wastewater with further reduced organic matter concentration.

11. The device according to claim 9 or 10, characterized in that The bioconversion pool is integrated with an ultrasonic function, and the ultrasonic treatment is performed after the bioconversion pool performs the bioconversion treatment for a preset time; or, A physical conversion tank is connected after the biological conversion tank, and the second pectin wastewater obtained after being treated in the biological conversion tank enters the physical conversion tank for ultrasonic treatment; The step of inputting the second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment comprises: subjecting the second pectin wastewater to ultrasonic treatment and then inputting the second pectin wastewater into one or more anaerobic reactors for anaerobic decomposition treatment.

12. The device according to claim 9 or 10, characterized in that The one-stage or multi-stage anaerobic reactor is also provided with an input port for low-concentration pectin wastewater, and the input port is used to input fourth pectin wastewater, the fourth pectin wastewater is obtained after partial pectin solidification and filtration of the third pectin wastewater, the third pectin wastewater and the first pectin wastewater are two parts obtained after high-concentration wastewater is diverted; the fourth pectin wastewater is low-concentration pectin wastewater, and the corresponding pectin concentration is 50mg / L-100mg / L; The fourth pectin wastewater is input together with the second pectin wastewater into a primary or multi-stage anaerobic reactor for anaerobic decomposition treatment; or the second pectin wastewater is input into a primary anaerobic reactor for anaerobic decomposition treatment, and after treatment, it is mixed with the fourth pectin wastewater and then input into a subsequent multi-stage anaerobic reactor for anaerobic decomposition treatment.

13. The device according to claim 9, characterized in that The wastewater inlet of the treatment equipment is used to be connected to the wastewater discharge outlet of the production equipment, and the production equipment is used to produce or process one or more of citrus canned food, alcohol, and coffee; the energy supply end or energy storage end is used to provide energy or store energy for the production equipment.

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