A biomass carbon source for cultivating granular sludge for sewage treatment and its preparation process

Abstract

The present invention relates to the technical field of sewage biochemical treatment, and in particular to a biomass carbon source for cultivating sewage treatment granular sludge and a preparation process thereof. The process comprises the following steps: preparation of cellulose template fluid; modification pretreatment of plant biomass; and fiberization and compounding of biomass carbon source. The present invention continuously sprays cellulose template fluid into a biomass mixed oil agent through electrostatic spinning. The formed biomass carbon source can provide a good initial growth carrier for microorganisms, promote the denitrification and phosphorus removal effect of microorganisms, and the modified biomass in the biomass mixed oil agent is modified by Fe 3+ It chelates with the cellulose template fluid to form a dense and uniform biomass film on the surface of the cellulose template fluid, which can provide a high C / N ratio in the sewage, promote the reproduction and self-flocculation of microorganisms in the sewage on the biomass carbon source, and have a more efficient denitrification ability in the sewage.

Description

Technical Field

[0001] The invention relates to the technical field of sewage biochemical treatment, and in particular to a biomass carbon source for cultivating sewage treatment granular sludge and a preparation process thereof. Background Art

[0002] Granular sludge is a microbial aggregate used to reduce the nitrogen and phosphorus content in sewage. It is formed by microbial self-flocculation and has the advantages of high biological retention, high density and good sedimentation performance. Due to the difference in dissolved oxygen mass transfer inside and outside the granular sludge, it can provide a reasonable ecological niche for anaerobic phosphorus release, anoxic denitrification, aerobic nitrification and aerobic excess phosphorus uptake reactions at the same time, and realize simultaneous nitrification and denitrification, and denitrification and phosphorus removal in a single-stage reaction zone.

[0003] However, due to insufficient carbon source in the influent of some sewage, the microbial self-flocculation start-up cycle is too long and cannot exist stably, which limits the large-scale promotion and application of the granular sludge process. In my country's urban domestic sewage generally has insufficient influent carbon source and low C / N. The low C / N influent of sewage treatment plants leads to poor denitrification and phosphorus removal by microorganisms. Therefore, supplementing the influent carbon source of domestic sewage treatment plants and studying and analyzing the denitrification and phosphorus removal have been hot topics that many researchers have been studying. Traditional carbon sources include methanol, sodium acetate, glucose, etc., and new carbon sources include natural solid organic matter that can be bioavailable and degraded.

[0004] A carrier is a substance with a special structure that can provide attachment points for microorganisms, thereby enabling the microorganisms to better self-flocculate. The above-mentioned traditional carbon sources have no fixed physical structure and cannot be used as carriers for granular sludge culture. Currently, there are few related studies and results on products that can be used as carriers for granular sludge culture and can also supplement the influent carbon source. Summary of the invention

[0005] In order to solve the above technical defects, the present invention has developed a biomass carbon source for culturing granular sludge for sewage treatment, which has a large specific surface area and can carry out sustained and efficient denitrification. It can be used as a carrier for the initial cultivation of granular sludge, and can also improve the C / N ratio of sewage and enhance the denitrification and phosphorus removal effects of microorganisms, and its preparation process.

[0006] A preparation process for a biomass carbon source for culturing granular sludge for sewage treatment comprises the following steps:

[0007] S1: Preparation of cellulose template fluid

[0008] Cutting plant fruits and vegetables into pieces and washing them with clean water, filtering and air-drying them to obtain washed fruit and vegetable particles, adding sodium phosphate solution to the washed fruit and vegetable particles and stirring them, then adding sodium percarbonate and heating and stirring them, filtering, washing and drying them to obtain fruit and vegetable cellulose, mixing the fruit and vegetable cellulose and cysteine ​​solution evenly, adding polyethylene glycol, and then performing ultrasonic treatment in an intermittent mode, and concentrating them to obtain a cellulose template fluid;

[0009] S2: Modification and pretreatment of plant biomass

[0010] The water polygonum and water hyacinth were washed, dried and crushed to obtain plant residues, which were then soaked in a NaOH solution, rinsed, and dried to obtain pretreated biomass, and a FeCl3 solution was prepared. The pretreated biomass was then added to the FeCl3 solution and stirred, filtered, and then dried to obtain modified biomass;

[0011] S3: Fiberization and compounding of biomass carbon sources

[0012] The modified biomass and glycerol aqueous solution are heated and stirred evenly to obtain a biomass mixed oil agent, the biomass mixed oil agent is placed in a cylindrical barrel, and a cellulose template fluid is sprayed into the biomass mixed oil agent using an electrostatic spinning machine. After standing and filtering, it is rinsed with deionized water and dried to obtain a biomass carbon source.

[0013] Furthermore, step S1 of preparing the cellulose template fluid comprises the following steps:

[0014] S1.1: Cut the plant fruits and vegetables into pieces and place them in a container, add 8-10 times the mass of clean water and stir, continue stirring for 10-15 minutes and then replace the clean water, repeat the above steps until the clean water becomes transparent, filter and air dry naturally to obtain cleaned fruit and vegetable pieces;

[0015] S1.2: 3-5 parts by weight of washed fruit and vegetable particles are placed in a container, 20-25 parts by weight of sodium phosphate solution are added and stirred for 15-20 minutes, and then 0.6-1 parts by weight of sodium percarbonate are added, and stirred at 60-65° C. and 150-200 rpm for 2-3 hours, filtered, washed with deionized water until neutral, and dried to obtain fruit and vegetable cellulose;

[0016] S1.3: Mix fruit and vegetable cellulose and 1-2% cysteine ​​solution in a solid-liquid ratio of 1:(18-20) in a container and stir evenly. Then add 1-3wt% polyethylene glycol, and then place it in an ultrasonic cleaner and perform ultrasonic treatment in an intermittent mode at a frequency of 20-25kHz for 20-30 minutes. After ultrasonicating for 10-15 seconds, stop for 5-6 seconds, and then concentrate to 1 / 4-1 / 3 of the original volume to obtain a cellulose template fluid.

[0017] Furthermore, step S2, the modification pretreatment of plant biomass, comprises the following steps:

[0018] S2.1: 1-2 parts by weight of Polygonum hydropiper and 2-3 parts by weight of Water Hyacinthus are rinsed and dried in an oven at 45-50°C to constant weight, and then mixed and crushed into slag to obtain plant debris, and the plant debris is soaked in a 1-2% NaOH solution at a mass ratio of 1:(80-100) for 1-2 days, and then taken out and rinsed with deionized water for 2-3 times, and then placed in an oven at 45-50°C to dry to constant weight to obtain pretreated biomass;

[0019] S2.2: Dissolve 0.8-1 parts by weight of FeCl3 in 25-30 parts by weight of deionized water to obtain a FeCl3 solution, add the pretreated biomass obtained in step S2.1 to the FeCl3 solution, stir at room temperature at a stirring speed of 300-350 rpm for 3-4 hours, then filter and place in an oven at 75-80°C to dry until there is no moisture, to obtain a modified biomass.

[0020] Furthermore, the fiberization and compounding of the biomass carbon source in step S3 comprises the following steps:

[0021] S3.1: Mix the modified biomass and the glycerol aqueous solution in a mass ratio of 1:(4-6) in a container, and stir at 80-90°C at a stirring speed of 350-400 rpm for 30-40 minutes to obtain a biomass mixed oil;

[0022] S3.2: 6-8 parts by weight of biomass mixed oil are placed in a cylindrical tube, and then an electrospinning machine is installed above the cylindrical tube, and the spinneret of the electrospinning machine is set to be 0.2-0.3 cm away from the liquid surface of the biomass mixed oil, and 1-2 parts by weight of cellulose template fluid are placed in the spinneret of the electrospinning machine, and the spinning voltage is set to 15-20 kV, the spinning temperature is set to 40-45 ° C, and the spinneret spinning speed is set to 8-10 mm / s, and then the electrospinning machine is started to allow the cellulose template fluid to be continuously sprayed into the biomass mixed oil. After it is completely sprayed in, let it stand for 15-20 minutes, filter out the solid matter, rinse it with deionized water, and dry it to obtain the biomass carbon source.

[0023] Furthermore, in step S1.1, the plant fruits and vegetables are cut into pieces and then passed through a mesh sieve to control the particle size of the pieces to be 0.5-1 cm.

[0024] Furthermore, the concentration of the sodium phosphate solution used for treating and washing the fruit and vegetable particles in step S1.2 is 4-6%.

[0025] Furthermore, the molecular weight of the polyethylene glycol selected in step S1.3 is between 800 and 1000.

[0026] Furthermore, the mass fraction of the glycerol aqueous solution used for mixing with the modifying substance in step S3.1 is 70-80%.

[0027] Furthermore, the aperture of the spinneret in step S3.2 is 0.04-0.06 mm.

[0028] A biomass carbon source for culturing granular sludge for sewage treatment is prepared by the above-mentioned preparation process of a biomass carbon source for culturing granular sludge for sewage treatment.

[0029] The beneficial effects are as follows: 1. The present invention continuously sprays the cellulose template fluid into the biomass mixed oil agent through electrostatic spinning. Under the viscosity of the cellulose template fluid and the biomass mixed oil agent, the cellulose template fluid curls to form an elastic spiral fiber structure. The formed biomass carbon source has a high specific surface area and environmental adaptability, can provide a good initial growth carrier for microorganisms, promote the denitrification and phosphorus removal effect of microorganisms, and the modified biomass in the biomass mixed oil agent is modified by the Fe 3+ It chelates with the cellulose template fluid to form a dense and uniform biomass film on the surface of the cellulose template fluid, which can provide a high C / N ratio in the sewage, promote the reproduction and self-flocculation of microorganisms in the sewage on the biomass carbon source, and have a more efficient denitrification ability in the sewage.

[0030] The present invention cleans and crushes water polygonum and water hyacinth and then soaks them in a NaOH solution for treatment, which can not only effectively remove lignin in the water polygonum and organic acid in the water hyacinth, but also the water polygonum containing more cellulose will swell and disperse in the NaOH solution, and combine with the water hyacinth with a loose cell structure after treatment to form a pretreated biomass with good mechanical strength and high adsorption sites, and can cooperate with each other to continuously and stably release soluble organic matter during the decomposition process, provide a rich carbon source for microorganisms, prolong the time of the high-efficiency denitrification period, and improve the sewage treatment effect.

[0031] The present invention washes the plants and fruits and places them in a sodium phosphate solution for treatment, and then adds sodium percarbonate for treatment. The sodium phosphate solution can help dissolve or decompose part of the lignin, hemicellulose and other impurities in the plants and fruits and reduce the interference of non-cellulose components. The addition of sodium percarbonate can gently purify the cellulose and introduce active groups such as carboxyl groups on the surface of the cellulose, so that the cellulose can form a stable suspension in water, prevent the nanofibers from agglomerating and agglomerating, and improve the uniformity and stability of subsequent cellulose template fluid spinning. In addition, the sulfhydryl groups are introduced by treating in a cysteine ​​solution, so that the composite metal Fe 3+ The modified biomass is better polymerized on the surface of the cellulose template fluid, and the formed biomass film can provide a carbon source more stably, thereby enhancing the denitrification effect of the biomass carbon source. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a process flow chart for preparing a biomass carbon source for culturing granular sludge for sewage treatment adopted in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] Example 1: A biomass carbon source for culturing granular sludge for sewage treatment and a preparation process thereof, such as Figure 1 As shown, the following steps are included:

[0035] S1: Preparation of cellulose template fluid

[0036] S1.1: Cut the plant fruits and vegetables into pieces with a particle size of 0.5 cm and place them in a container. Add 8 times the mass of clean water and stir. After 10 minutes, replace the clean water. Repeat the above steps until the clean water becomes transparent. After filtering, naturally air-dry to obtain cleaned fruit and vegetable particles.

[0037] S1.2: 3 parts by weight of washed fruit and vegetable particles are placed in a container, 20 parts by weight of sodium phosphate solution is added and stirred for 15 minutes, and then 0.6 parts by weight of sodium percarbonate is added, and stirred at 60°C and 150 rpm for 2 hours, filtered, washed with deionized water until neutral, and dried to obtain fruit and vegetable cellulose;

[0038] S1.3: Mix fruit and vegetable cellulose and 1% cysteine ​​solution in a solid-liquid ratio of 1:18 in a container and stir evenly. Then add 1wt% polyethylene glycol with a molecular weight of 800. Then place it in an ultrasonic cleaner and perform ultrasonic treatment for 20 minutes in intermittent mode at a frequency of 20 kHz. After ultrasonicating for 10 seconds, stop for 5 seconds and then concentrate to 1 / 4 of the original volume to obtain a cellulose template fluid.

[0039] S2: Modification and pretreatment of plant biomass

[0040] S2.1: 1 part by weight of Polygonum hydropiper and 2 parts by weight of Water Hyacinthus are rinsed and dried in an oven at 45°C to constant weight, then mixed and crushed into slag to obtain plant debris, and the plant debris is soaked in a 1% NaOH solution at a mass ratio of 1:80 for 1 day, taken out and rinsed twice with deionized water, and then placed in an oven at 45°C to dry to constant weight to obtain pretreated biomass;

[0041] S2.2: Dissolve 0.8 parts by weight of FeCl3 in 25 parts by weight of deionized water to obtain a FeCl3 solution, add the pretreated biomass obtained in step S2.1 to the FeCl3 solution, stir at room temperature at a stirring speed of 300 rpm for 3 hours, then filter and place in an oven at 75°C to dry until there is no moisture, to obtain a modified biomass.

[0042] S3: Fiberization and compounding of biomass carbon sources

[0043] S3.1: The modified biomass and a 70% glycerol aqueous solution are mixed in a mass ratio of 1:4 in a container, and stirred at 80°C at a stirring speed of 350 rpm for 30 minutes to obtain a biomass mixed oil;

[0044] S3.2: 6 parts by weight of biomass mixed oil are placed in a cylindrical tube, and then an electrospinning machine is installed above the cylindrical tube, and the spinneret of the electrospinning machine is set to be 0.2 cm away from the liquid surface of the biomass mixed oil. 1 part by weight of cellulose template fluid is placed in the spinneret of the electrospinning machine, and the aperture of the spinneret is 0.04 mm. The spinning voltage is set to 15 kV, the spinning temperature is 40 ° C, and the spinning speed of the spinneret is 8 mm / s. Then, the electrospinning machine is started, and the cellulose template fluid is continuously sprayed into the biomass mixed oil. After it is completely sprayed in, it is allowed to stand for 15 minutes, and the solid matter is filtered and rinsed with deionized water, and then dried to obtain the biomass carbon source.

[0045] Example 2: A biomass carbon source for culturing granular sludge for sewage treatment and a preparation process thereof, such as Figure 1 As shown, the following steps are included:

[0046] S1: Preparation of cellulose template fluid

[0047] S1.1: Cut the plant fruits and vegetables into pieces with a particle size of 0.5 cm and place them in a container. Add 8 times the mass of clean water and stir. After 10 minutes, replace the clean water. Repeat the above steps until the clean water becomes transparent. After filtering, naturally air-dry to obtain cleaned fruit and vegetable particles.

[0048] S1.2: 5 parts by weight of washed fruit and vegetable particles are placed in a container, 25 parts by weight of sodium phosphate solution is added and stirred for 15 minutes, 1 part by weight of sodium percarbonate is added, and the mixture is stirred at 60°C and 150 rpm for 2 hours, filtered, washed with deionized water until neutral, and dried to obtain fruit and vegetable cellulose;

[0049] S1.3: Mix fruit and vegetable cellulose and 1% cysteine ​​solution in a solid-liquid ratio of 1:18 in a container and stir evenly. Then add 3wt% polyethylene glycol with a molecular weight of 800. Then place it in an ultrasonic cleaner and perform ultrasonic treatment for 20 minutes in intermittent mode at a frequency of 20kHz. After ultrasonicating for 10 seconds, stop for 5 seconds and then concentrate to 1 / 4 of the original volume to obtain a cellulose template fluid.

[0050] S2: Modification and pretreatment of plant biomass

[0051] S2.1: 2 parts by weight of Polygonum hydropiper and 3 parts by weight of Water Hyacinth are rinsed and dried in an oven at 45°C to constant weight, then mixed and crushed into slag to obtain plant debris, and the plant debris is soaked in a 1% NaOH solution at a mass ratio of 1:100 for 1 day, taken out and rinsed twice with deionized water, and then placed in an oven at 45°C to dry to constant weight to obtain pretreated biomass;

[0052] S2.2: Dissolve 1 part by weight of FeCl3 in 30 parts by weight of deionized water to obtain a FeCl3 solution, add the pretreated biomass obtained in step S2.1 to the FeCl3 solution, stir at room temperature at a stirring speed of 300 rpm for 3 hours, then filter and place in an oven at 75°C to dry until there is no moisture, to obtain a modified biomass.

[0053] S3: Fiberization and compounding of biomass carbon sources

[0054] S3.1: The modified biomass and a 70% glycerol aqueous solution are mixed in a mass ratio of 1:6 in a container, and stirred at 80°C at a stirring speed of 350 rpm for 30 minutes to obtain a biomass mixed oil;

[0055] S3.2: 8 parts by weight of biomass mixed oil are placed in a cylindrical tube, and then an electrospinning machine is installed above the cylindrical tube, and the spinneret of the electrospinning machine is set to be 0.2 cm away from the liquid surface of the biomass mixed oil, and 2 parts by weight of cellulose template fluid are placed in the spinneret of the electrospinning machine, the aperture of the spinneret is 0.04 mm, the spinning voltage is set to 15 kV, the spinning temperature is 40 ° C, and the spinning speed of the spinneret is 8 mm / s. Then, the electrospinning machine is started, and the cellulose template fluid is continuously sprayed into the biomass mixed oil. After it is completely sprayed in, it is allowed to stand for 15 minutes, and the solid matter is filtered and rinsed with deionized water, and then dried to obtain the biomass carbon source.

[0056] Example 3: A biomass carbon source for culturing granular sludge for sewage treatment and a preparation process thereof, such as Figure 1 As shown, the following steps are included:

[0057] S1: Preparation of cellulose template fluid

[0058] S1.1: Cut the plant fruits and vegetables into 1 cm particle size pieces and place them in a container, add 10 times the mass of clean water and stir, continue stirring for 15 minutes and then replace the clean water, repeat the above steps until the clean water becomes transparent, filter and air dry naturally to obtain cleaned fruit and vegetable particles;

[0059] S1.2: 3 parts by weight of washed fruit and vegetable particles are placed in a container, 20 parts by weight of sodium phosphate solution are added and stirred for 20 minutes, and then 1 part by weight of sodium percarbonate is added, and stirred at 65°C at a stirring speed of 200 rpm for 3 hours, filtered, washed with deionized water until neutral, and dried to obtain fruit and vegetable cellulose;

[0060] S1.3: Mix fruit and vegetable cellulose and 2% cysteine ​​solution in a solid-liquid ratio of 1:20 in a container and stir evenly. Then add 3wt% polyethylene glycol with a molecular weight of 1000. Then place it in an ultrasonic cleaner and perform ultrasonic treatment in intermittent mode at a frequency of 25kHz for 30 minutes. After ultrasonicating for 15 seconds, stop for 6 seconds and then concentrate to 1 / 3 of the original volume to obtain a cellulose template fluid.

[0061] S2: Modification and pretreatment of plant biomass

[0062] S2.1: 1 part by weight of Polygonum hydropiper and 2 parts by weight of Water Hyacinthus are rinsed and dried in an oven at 50°C to constant weight, then mixed and crushed into slag to obtain plant debris, and the plant debris is soaked in a 2% NaOH solution at a mass ratio of 1:80 for 2 days, taken out and rinsed with deionized water for 3 times, and then placed in an oven at 50°C to dry to constant weight to obtain pretreated biomass;

[0063] S2.2: Dissolve 0.8 parts by weight of FeCl3 in 25 parts by weight of deionized water to obtain a FeCl3 solution, add the pretreated biomass obtained in step S2.1 to the FeCl3 solution, stir at room temperature at a stirring speed of 350 rpm for 4 hours, then filter and place in an oven at 80°C to dry until there is no moisture, to obtain a modified biomass.

[0064] S3: Fiberization and compounding of biomass carbon sources

[0065] S3.1: The modified biomass and a glycerol aqueous solution with a mass fraction of 80% are mixed in a mass ratio of 1:4 in a container, and stirred at 90°C at a stirring speed of 400 rpm for 40 minutes to obtain a biomass mixed oil;

[0066] S3.2: 6 parts by weight of biomass mixed oil are placed in a cylindrical tube, and then an electrospinning machine is installed above the cylindrical tube, and the spinneret of the electrospinning machine is set to be 0.3 cm away from the liquid surface of the biomass mixed oil. 1 part by weight of cellulose template fluid is placed in the spinneret of the electrospinning machine, and the aperture of the spinneret is 0.06 mm. The spinning voltage is set to 20 kV, the spinning temperature is 45 ° C, and the spinning speed of the spinneret is 10 mm / s. Then, the electrospinning machine is started, and the cellulose template fluid is continuously sprayed into the biomass mixed oil. After it is completely sprayed in, it is allowed to stand for 20 minutes, and the solid matter is filtered and rinsed with deionized water, and then dried to obtain the biomass carbon source.

[0067] Comparative Example 1: The difference between Comparative Example 1 and Example 1 is that Comparative Example 1 removes step S3, and directly puts 1 weight part of cellulose template fluid and 1.2 weight parts of modified biomass into deionized water, mixes them evenly, and then dries them. The remaining steps are the same as Example 1 to obtain a biomass carbon source, which is recorded as Comparative Example 1.

[0068] Comparative Example 2: The difference between Comparative Example 2 and Example 1 is that in Comparative Example 2, the water hyacinth in step S2.1 is replaced with an equal amount of Polygonum hydropiper, and the remaining steps are the same as those in Example 1 to obtain a biomass carbon source, which is recorded as Comparative Example 2.

[0069] Comparative Example 3: The difference between Comparative Example 3 and Example 1 is that in Comparative Example 3, the Polygonum hydropiper in step S2.1 is replaced with an equal amount of Water hyacinth, and the remaining steps are the same as Example 1 to obtain a biomass carbon source, which is recorded as Comparative Example 3.

[0070] Comparative Example 4: The difference between Comparative Example 4 and Example 1 is that Comparative Example 4 removes step S1.2, directly placing the cleaned fruit and vegetable particles in a sodium hydroxide solution of the same concentration as the sodium phosphate solution, and adding hydrogen peroxide of the same mass as the sodium percarbonate for treatment, and the remaining steps are the same as Example 1 to obtain a biomass carbon source, which is recorded as Comparative Example 4.

[0071] Experiment 1: A 250mL sealable Meng's wash bottle was used as a reaction device, 200mL of simulated sewage and 1mL of denitrifying bacteria inoculum were added to the reaction bottle, and the biomass carbon source prepared in the embodiment and the biomass carbon source prepared in Comparative Examples 1-4 were added with equal mass, and the initial COD in each batch of experimental reactors was 150mg / L, and sodium nitrate was added to make the initial concentration of total nitrogen TN 30mg / L. The sludge concentration of each group of experiments was configured to be 5000mg / L. After the biomass was added, nitrogen was passed through the reaction bottle for 5min and then sealed with a rubber stopper, and placed in a constant temperature incubator at 25°C for reaction. After 48h, the reaction solution was discharged and filtered with a 0.45μm filter membrane. The total nitrogen concentration TN of the filtrate was determined, and the experiment was repeated for three batches, and the concentration change of TN was recorded and tabulated, as shown in Table 1.

[0072] It can be seen from Table 1 that the total nitrogen TN concentration of the effluent after the sewage treatment by the biomass carbon source prepared in the embodiment is lower than the total nitrogen TN concentration of the effluent after the sewage treatment by Comparative Examples 1-4, which can prove that the continuous spraying of the cellulose template fluid into the biomass mixed oil agent by electrospinning can make the formed biomass carbon source have a more efficient denitrification ability, and can also prove that the denitrification effect of the biomass carbon source can be enhanced after washing the plants and fruits and vegetables and then treating them in sodium phosphate solution and sodium percarbonate.

[0073] And it can be seen from Table 1 that by comparing the data of Comparative Examples 2 and 3 with the data of the embodiment, it can be seen that the denitrification effects of Comparative Examples 2 and 3 are both reduced, indicating that replacing equal amounts of Polygonum hydropiper and Water hyacinth will affect the denitrification effect. It can be proved that there is a synergistic effect between the two substances, which can jointly promote the sewage treatment effect in the biomass carbon source.

[0074] Table 1: Total nitrogen TN concentration in effluent

[0075] Total nitrogen TN concentration in effluent (mg / L) First batch Second batch The third batch Example 1 0.51 0.48 0.46 Example 2 0.73 0.79 0.75 Example 3 0.43 0.41 0.44 Comparative Example 1 3.17 3.12 3.18 Comparative Example 2 1.23 1.19 1.25 Comparative Example 3 1.14 1.12 1.15 Comparative Example 4 2.01 1.96 1.95

[0076] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A process for preparing a biomass carbon source for culturing granular sludge for sewage treatment, characterized in that: The following steps are involved: S1: Preparation of cellulose template fluid Cutting plant fruits and vegetables into pieces and washing them with clean water, filtering and air-drying them to obtain washed fruit and vegetable particles, adding sodium phosphate solution to the washed fruit and vegetable particles and stirring them, then adding sodium percarbonate and heating and stirring them, filtering, washing and drying them to obtain fruit and vegetable cellulose, mixing the fruit and vegetable cellulose and cysteine ​​solution evenly, adding polyethylene glycol, and then performing ultrasonic treatment in an intermittent mode, and concentrating them to obtain a cellulose template fluid; S2: Modification and pretreatment of plant biomass The water polygonum and water hyacinth were washed, dried and crushed to obtain plant residues, which were soaked in a NaOH solution, rinsed and dried to obtain pretreated biomass, and a FeCl3 solution was prepared. The pretreated biomass was then added to the FeCl3 solution and stirred, filtered and dried to obtain modified biomass; S3: Fiberization and compounding of biomass carbon sources The modified biomass and the glycerol aqueous solution are heated and stirred evenly to obtain a biomass mixed oil agent, the biomass mixed oil agent is placed in a cylindrical barrel, a cellulose template fluid is sprayed into the biomass mixed oil agent by an electrostatic spinning machine, the biomass mixed oil agent is allowed to stand and filtered, and then rinsed with deionized water, and dried to obtain a biomass carbon source; Step S2: modification pretreatment of plant biomass, comprising the following steps: S2.1: 1-2 parts by weight of Polygonum hydropiper and 2-3 parts by weight of Water Hyacinth are rinsed and dried in an oven at 45-50°C to constant weight, and then mixed and crushed into slag to obtain plant debris, and the plant debris is soaked in a 1-2% NaOH solution at a mass ratio of 1:(80-100) for 1-2 days, and then taken out and rinsed with deionized water for 2-3 times, and then placed in an oven at 45-50°C to dry to constant weight to obtain pretreated biomass; S2.2: 0.8-1 parts by weight of FeCl3 is dissolved in 25-30 parts by weight of deionized water to obtain a FeCl3 solution, the pretreated biomass obtained in step S2.1 is added to the FeCl3 solution, stirred at a stirring speed of 300-350 rpm at room temperature for 3-4 hours, then filtered and placed in an oven at 75-80°C to dry until there is no moisture, to obtain a modified biomass; Step S3: Fiberization and compounding of biomass carbon source, including the following steps: S3.1: Mix the modified biomass and the glycerol aqueous solution in a mass ratio of 1:(4-6) in a container, and stir at 80-90°C at a stirring speed of 350-400 rpm for 30-40 minutes to obtain a biomass mixed oil; S3.2: 6-8 parts by weight of biomass mixed oil are placed in a cylindrical tube, and then an electrospinning machine is installed above the cylindrical tube, and the spinneret of the electrospinning machine is set to be 0.2-0.3 cm away from the liquid surface of the biomass mixed oil, and 1-2 parts by weight of cellulose template fluid are placed in the spinneret of the electrospinning machine, and the spinning voltage is set to 15-20 kV, the spinning temperature is set to 40-45 ° C, and the spinneret spinning speed is set to 8-10 mm / s, and then the electrospinning machine is started to allow the cellulose template fluid to be continuously sprayed into the biomass mixed oil. After it is completely sprayed in, let it stand for 15-20 minutes, filter out the solid matter, rinse it with deionized water, and dry it to obtain the biomass carbon source.

2. The process for preparing a biomass carbon source for culturing granular sludge for sewage treatment according to claim 1, characterized in that: Step S1: Preparation of cellulose template fluid, comprising the following steps: S1.1: Cut the plant fruits and vegetables into pieces and place them in a container, add 8-10 times the mass of clean water and stir, continue stirring for 10-15 minutes and then replace the clean water, repeat the above steps until the clean water becomes transparent, filter and air dry naturally to obtain cleaned fruit and vegetable pieces; S1.2: 3-5 parts by weight of washed fruit and vegetable particles are placed in a container, 20-25 parts by weight of sodium phosphate solution are added and stirred for 15-20 minutes, and then 0.6-1 parts by weight of sodium percarbonate are added, and stirred at 60-65° C. and 150-200 rpm for 2-3 hours, filtered, washed with deionized water until neutral, and dried to obtain fruit and vegetable cellulose; S1.3: Mix fruit and vegetable cellulose and 1-2% cysteine ​​solution in a solid-liquid ratio of 1:(18-20) in a container and stir evenly. Then add 1-3wt% polyethylene glycol, and then place it in an ultrasonic cleaner and perform ultrasonic treatment in an intermittent mode at a frequency of 20-25kHz for 20-30 minutes. After ultrasonicating for 10-15 seconds, stop for 5-6 seconds, and then concentrate to 1 / 4-1 / 3 of the original volume to obtain a cellulose template fluid.

3. The process for preparing a biomass carbon source for culturing granular sludge for sewage treatment according to claim 2, characterized in that: Step S1.1: Cut the plant fruits and vegetables into pieces and pass them through a mesh sieve to control the particle size of the pieces to 0.5-1 cm.

4. The process for preparing a biomass carbon source for culturing granular sludge for sewage treatment according to claim 2, characterized in that: The concentration of the sodium phosphate solution used for treating and washing the fruit and vegetable particles in step S1.2 is 4-6%.

5. The process for preparing a biomass carbon source for culturing granular sludge for sewage treatment according to claim 2, characterized in that: The molecular weight of the polyethylene glycol selected in step S1.3 is between 800 and 1000.

6. The process for preparing a biomass carbon source for culturing granular sludge for sewage treatment according to claim 1, characterized in that: The mass fraction of the glycerol aqueous solution used for mixing with the modifying substance in step S3.1 is 70-80%.

7. The process for preparing a biomass carbon source for culturing granular sludge for sewage treatment according to claim 1, characterized in that: The aperture of the spinneret in step S3.2 is 0.04-0.06 mm.

8. A biomass carbon source for culturing granular sludge for sewage treatment, characterized in that: The biomass carbon source for culturing granular sludge for sewage treatment is prepared by the preparation process of any one of claims 1 to 7.

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