An ecological water treatment process

Abstract

This invention discloses an ecological water treatment process, comprising the following steps: treatment using a fluidized bed biofilm reactor; adding cellulose / sepiolite composite packing material and nutrient solution to the fluidized bed biofilm reactor; inoculating the fluidized bed biofilm reactor with activated sludge and performing an aeration reaction; operating the fluidized bed biofilm reactor with continuous ecological water intake, aeration reaction, and pH adjustment within the system; continuous sludge recirculation from the secondary sedimentation tank of the fluidized bed biofilm reactor during operation; when the water treatment packing material in the fluidized bed biofilm reactor reaches a certain thickness, adjusting the dissolved oxygen and pH within the system; continuous sludge recirculation from the secondary sedimentation tank of the fluidized bed biofilm reactor, and effluent. This treatment process can effectively degrade toxic organic substances in ecological water and exhibits excellent adsorption and high removal rates for antibiotic residues, achieving the purpose of purifying ecological water.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of water treatment, and particularly relates to an ecological water treatment process. BACKGROUND

[0002] Ecological water treatment refers to treating water sources by using original ecological and healthy methods, that is, further optimizing the producers, consumers, decomposers and users in nature, optimizing the configuration thereof, enriching and developing the entire biological chain, and making the ecological system more and more harmonious and stable, so as to purify water sources by using the purification function of nature itself and achieve the purpose of ensuring water source health. Nowadays, it is also very difficult for people to drink healthy water, so ecological water treatment is particularly important. Through ecological treatment of water sources, the water quality can reach more than three classes. The first class of water quality is the best, green and non-hazardous, but it is now very rare. Through ecological water treatment of water sources, the water quality can be improved, which can alleviate the problem of urban water shortage. At the same time when people drink and use water, the optimization of ecological water treatment to the human body can be maximized, and the optimization and greening of the environment can also be maximized.

[0003] With the development of modern industry, especially chemical synthesis industry, the material world of human beings is greatly enriched, and the development of industry and agriculture and modern science and technology is promoted, but many synthetic toxic chemicals enter the environment through various channels, causing harm to the ecological environment and human health. In particular, the toxic organic matter which is difficult to degrade has attracted great attention due to its potential ecological and health hazards. The toxic organic pollutants in the environment are often difficult to biodegrade, can accumulate in biological lipids, and can be transmitted in the food chain through biological enrichment and concentration, that is, have biological amplification effect and potential "three effects" (carcinogenic, teratogenic, and mutagenic) effect or chronic toxicity. Once entering the water environment, these pollutants can be enriched in different levels of organisms through the food chain, starting from the molecular level of toxicity, and then reflecting the ecological effects at the levels of cell-organ-individual-population-colony-ecosystem. SUMMARY

[0004] The present application aims to provide a composite filler with more pore structure, which is used as a filler and used in ecological water treatment with nutrient solution and active pollutants, and can effectively degrade toxic organic matter (polycyclic aromatic hydrocarbons, benzopyrene, polychlorinated biphenyl) and antibiotic residues (tetracycline, norfloxacin, oxytetracycline, dehydrated erythromycin) in ecological water, has excellent adsorption effect and high removal rate, and achieves the purpose of purifying ecological water.

[0005] The technical scheme adopted by the present application to achieve the above-mentioned purpose is as follows:

[0006] An ecological water treatment process comprises the following steps:

[0007] Step 1: using a fluidized bed biofilm reactor to treat, adding cellulose / sepiolite composite filler and nutrient solution into the fluidized bed biofilm reactor;

[0008] Step 2: inoculating activated sludge into the fluidized bed biofilm reactor and performing aeration reaction;

[0009] Step 3: continuously feeding ecological water into the fluidized bed biofilm reactor to perform aeration reaction, adjusting the pH in the system to 6.3-7.8, continuously returning sludge from the secondary sedimentation tank of the fluidized bed biofilm reactor, the sludge return ratio being 150-200%, continuously operating for 48-72h;

[0010] Step 4: according to the biofilm thickness on the surface of the filler for water treatment in the fluidized bed biofilm reactor, adjusting the dissolved oxygen in the system to 0.55-0.85mg / L and adjusting the pH in the system to 6.3-7.8, continuously returning sludge from the secondary sedimentation tank of the fluidized bed biofilm reactor, the sludge return ratio being 150-200%, continuously operating for 48-72h, and discharging water.

[0011] Further, in some embodiments, the filling ratio of the cellulose / sepiolite composite filler in the fluidized bed biofilm reactor is 32-45%, the amount of the nutrient solution is 15-40g / L, the cellulose / sepiolite composite material is used as the filler and is used with the nutrient solution and activated sludge for ecological water treatment, a biofilm is formed on the surface of the filler during long-time aeration, microorganisms multiply in the biofilm in large quantities, the nutrient solution provides essential nutrients for the growth of the microorganisms and promotes the multiplication of the microorganisms, the biofilm fully contacts with pollutants in the ecological water, can effectively degrade toxic organic substances (polycyclic aromatic hydrocarbons, benzopyrene, polychlorinated biphenyl) and antibiotic residues (tetracycline, norfloxacin, oxytetracycline, dehydrated erythromycin) in the ecological water, has excellent adsorption effect and higher removal rate, and achieves the purpose of purifying the ecological water.

[0012] Further, in some embodiments, the preparation method of the cellulose / sepiolite composite filler is as follows:

[0013] Cotton cellulose is dissolved in frozen 0.1-0.2 mol / L sodium hydroxide aqueous solution to prepare a cellulose solution with a concentration of 5-15 wt%, and the cellulose is completely dispersed and dissolved by using a high-speed homogenizer at a speed of 15000-18000 rpm for 5-10 min. Then, sepiolite is added to the cellulose solution in a mass ratio of 1:0.3-1, and the mixture is uniformly dispersed by using a high-speed homogenizer at a speed of 15000-18000 rpm for 5-10 min. Then, the mixture is added dropwise into a coagulation bath containing 1-1.5 mol / L hydrochloric acid solution by using a syringe, and a cellulose / sepiolite composite filler is obtained by magnetic stirring.

[0014] Further, in some embodiments, the composite filler is a modified cellulose / sepiolite composite material, and the filling ratio of the modified cellulose / sepiolite composite filler in the flow bed biofilm reactor is 35-40%.

[0015] Further, in some embodiments, the modified cellulose is cotton cellulose modified by 5-benzyloxytryptamine acid. The cotton cellulose modified by 5-benzyloxytryptamine acid has more uniform pore structures, and the composite filler prepared by combining the cotton cellulose with sepiolite has improved removal rates of toxic organic substances (polycyclic aromatic hydrocarbons, benzopyrene, polychlorinated biphenyl) and antibiotic residues (tetracycline, norfloxacin, oxytetracycline, and anhydrous erythromycin) in ecological water. This may be because the modified cellulose contains more active groups, which have a strong adsorption effect on heavy metals and a more excellent treatment effect on ecological water.

[0016] Further, in some embodiments, the preparation method of the modified cellulose is as follows:

[0017] Cotton cellulose is mixed with 5-benzyloxytryptamine acid at a mass ratio of 1:2-5, and the mixture is ground into fine powder under an infrared lamp for 30-60 min. Then, 20-50 parts by weight of DMSO is added and ultrasonically stirred for 30-60 min, and the mixture is stirred and reacted in an oil bath at 110-125°C. Under stirring, 0.5-0.8 parts by weight of sulfuric acid catalyst is added and reacted for 5-8 h. After cooling to room temperature, the mixture is filtered, washed with ethanol and deionized water, washed with saturated sodium bicarbonate and deionized water until neutral, and finally washed with ethanol and acetone, and dried at 75-85°C to obtain the modified cellulose.

[0018] Further, in some embodiments, the nutrient solution includes disodium hydrogen phosphate, ammonium sulfate, ammonium glycyrrhizate, calcium gluconate, urea, isomaltulose, and magnesium sulfate.

[0019] Further, in some embodiments, the sodium phosphate dibasic is 0.5-1.5 parts, the ammonium sulfate is 0.005-0.01 parts, the ammonium glycyrrhizinate is 0.05-0.1 parts, the calcium gluconate is 10-20 parts, the urea is 5-10 parts, the isomaltulose is 1-3 parts, and the magnesium sulfate is 0.05-0.1 parts in the nutrient solution by weight.

[0020] In some specific embodiments, 0.05-0.15 parts of N-formyl-L-aspartyl-L-phenylalanine methyl ester is further added in the nutrient solution; the addition of N-formyl-L-aspartyl-L-phenylalanine methyl ester further improves the removal of antibiotic residues and toxic organic substances in the ecological water, which may be because N-formyl-L-aspartyl-L-phenylalanine methyl ester has a synergistic effect with other components in the nutrient solution, thereby improving the purification effect on the ecological water.

[0021] Further, in some embodiments, the activated sludge is aerobic activated sludge, and the amount of the activated sludge in the fluidized bed biofilm reactor is 2.5-7.5 g / L.

[0022] Further, in some embodiments, the removal rate of polycyclic aromatic hydrocarbon compounds in the ecological water is higher than 91%, and the removal rate of polychlorinated biphenyl is higher than 90%.

[0023] The application also discloses a use of the modified cellulose / sepiolite composite filler in improving the removal rate of toxic organic substances and / or antibiotic residues in ecological water.

[0024] The application has the following advantages:

[0025] 1) The application uses cellulose / sepiolite composite material as the filler, and uses the nutrient solution and activated sludge for ecological water treatment; a biofilm is formed on the surface of the filler during a long-time aeration process, and microorganisms multiply in the biofilm; the nutrient solution provides necessary nutrients for the growth of the microorganisms, thereby promoting the multiplication of the microorganisms; the biofilm is in full contact with pollutants in the ecological water, and can effectively degrade toxic organic substances (polycyclic aromatic hydrocarbons, benzopyrene and polychlorinated biphenyl) and antibiotic residues (tetracycline, norfloxacin, oxytetracycline and anhydrous erythromycin) in the ecological water, has excellent adsorption effect and high removal rate, and thus achieves the purpose of purifying the ecological water.

[0026] 2) The 5-benzyloxytryptamine acid modified cotton cellulose has a large number of pore structures and uniform distribution, and is combined with sepiolite to prepare the composite filler; and the composite filler further improves the removal rate of toxic organic substances (polycyclic aromatic hydrocarbons, benzopyrene and polychlorinated biphenyl) and antibiotic residues (tetracycline, norfloxacin, oxytetracycline and anhydrous erythromycin) in the ecological water.

[0027] Therefore, the present application is a composite filler with more porous structure, which is used as filler and is used in ecological water treatment with nutrient solution and active pollutants, and has excellent adsorption and higher removal rate for toxic organic substances and antibiotic residues in ecological water, so as to purify ecological water. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The infrared spectrum of cellulose before and after modification in Example 2 is shown in the following figure.

[0029] Figure 2 The cross-section SEM image of the cellulose / sepiolite composite filler in Example 1 is shown in the following figure.

[0030] Figure 3 The cross-section SEM image of the modified cellulose / sepiolite composite filler in Example 2 is shown in the following figure. DETAILED DESCRIPTION

[0031] The cotton cellulose used in the embodiment of the present application is purchased from Shanghai Yuan Ye Biological Technology Co., Ltd., and the purity is greater than or equal to 99%.

[0032] The technical solutions of the present application are described in further detail in combination with specific embodiments and the accompanying drawings as follows:

[0033] Example 1

[0034] An ecological water treatment process comprises the following steps:

[0035] Step 1: The flow bed biofilm reactor equipment is used for treatment, and the cellulose / sepiolite composite filler and nutrient solution are added into the flow bed biofilm reactor, wherein the filling ratio of the cellulose / sepiolite composite filler is 35%, the dosage of the nutrient solution is 20 g / L, and the nutrient solution comprises 0.5 parts by weight of sodium phosphate dibasic, 0.008 parts by weight of ammonium sulfate, 0.05 parts by weight of ammonium glycyrrhizinate, 10 parts by weight of calcium gluconate, 5 parts by weight of urea, 1 part by weight of isomaltulose, and 0.05 parts by weight of magnesium sulfate, so as to provide nutrients for microorganisms and promote the reproduction of microorganisms;

[0036] Step 2: The aerobic active sludge with a dosage of 3.5 g / L is inoculated into the flow bed biofilm reactor, and the aeration reaction is performed for 24 h;

[0037] Step 3: The flow bed biofilm reactor is operated in a continuous ecological water feeding mode, the aeration reaction is performed, the pH in the system is adjusted to 7.2, the sludge in the secondary sedimentation tank of the flow bed biofilm reactor is continuously backflowed, the sludge backflow ratio is 150%, and the continuous operation is performed for 48 h;

[0038] Step 4: Based on the biofilm thickness on the surface of the water treatment packing material in the fluidized bed biofilm reactor, when a darker color is visible on the biofilm surface, adjust the dissolved oxygen in the system to 0.55 mg / L and adjust the pH of the system to 7.5. Continuously recycle the sludge from the secondary sedimentation tank of the fluidized bed biofilm reactor at a sludge recycling ratio of 150% for 48 hours, and then effluent is produced.

[0039] In this embodiment, the preparation method of the cellulose / sepiolite composite filler is as follows:

[0040] Cotton cellulose was dissolved in a frozen 0.1 mol / L sodium hydroxide aqueous solution to prepare a 10 wt% cellulose solution. The cellulose was completely dispersed and dissolved using a high-speed homogenizer at 18,000 rpm for 5 min. Then, sepiolite was added to the cellulose solution at a mass ratio of 1:0.5, and the mixture was uniformly dispersed using a high-speed homogenizer at 15,000 rpm for 5 min to obtain a mixture. The mixture was then added dropwise to a coagulation bath containing 1 mol / L hydrochloric acid solution using a syringe and magnetically stirred to obtain a cellulose / sepiolite composite filler.

[0041] Example 2:

[0042] An ecological water treatment process includes the following steps:

[0043] Step 1: The process is carried out using a fluidized bed biofilm reactor. Modified cellulose / sepiolite composite packing material and nutrient solution are added to the fluidized bed biofilm reactor. The filling ratio of cellulose / sepiolite composite packing material is 35%, and the amount of nutrient solution is 20 g / L. The nutrient solution includes 0.5 parts by weight of disodium hydrogen phosphate, 0.008 parts by weight of ammonium sulfate, 0.05 parts by weight of ammonium glycyrrhizate, 10 parts by weight of calcium gluconate, 5 parts by weight of urea, 1 part by weight of isomaltulose, and 0.05 parts by weight of magnesium sulfate to provide nutrients for microorganisms and promote their proliferation.

[0044] The other steps are the same as in Example 1;

[0045] In this embodiment, the modified cellulose is prepared as follows: cotton cellulose and 5-benzyloxytryptamine are mixed at a mass ratio of 1:2.5, ground under an infrared lamp for 30 min to obtain a fine powder, then 20 parts by weight of DMSO are added and ultrasonically stirred for 30 min, placed in an oil bath at 115℃ and stirred to react, and 0.5 parts by weight of sulfuric acid catalyst are added under stirring and reacted for 6 h, cooled to room temperature, filtered, washed with ethanol and deionized water, then washed with saturated sodium bicarbonate and deionized water until neutral, and finally washed with ethanol and acetone three times in sequence, and dried at 75℃ to obtain modified cellulose;

[0046] In this embodiment, the preparation method of the modified cellulose / sepiolite composite filler is as follows:

[0047] Modified cellulose was dissolved in a frozen 0.1 mol / L sodium hydroxide aqueous solution to prepare a 10 wt% cellulose solution. The cellulose was completely dispersed and dissolved using a high-speed homogenizer at 18,000 rpm for 5 min. Then, sepiolite was added to the cellulose solution at a mass ratio of 1:0.5, and the mixture was uniformly dispersed using a high-speed homogenizer at 15,000 rpm for 5 min to obtain a mixture. The mixture was then added dropwise to a coagulation bath containing 1 mol / L hydrochloric acid solution using a syringe and magnetically stirred to obtain a cellulose / sepiolite composite filler.

[0048] Example 3:

[0049] An ecological water treatment process is described, with all other steps being the same as in Example 2. The difference from Example 2 is that in step 1, the amount of nutrient solution used in the fluidized bed biofilm reactor is 30 g / L, and the nutrient solution includes 1 part by weight of disodium hydrogen phosphate, 0.01 parts by weight of ammonium sulfate, 0.07 parts by weight of ammonium glycyrrhizate, 15 parts by weight of calcium gluconate, 8 parts by weight of urea, 1.5 parts by weight of isomaltulose, and 0.05 parts by weight of magnesium sulfate.

[0050] Example 4:

[0051] An ecological water treatment process, in which all other steps are the same as in Example 2, except that:

[0052] In this embodiment, the modified cellulose is prepared as follows: cotton cellulose and 5-benzyloxytryptamine are mixed at a mass ratio of 1:4.5, ground under an infrared lamp for 50 min to obtain a fine powder, then 50 parts by weight of DMSO are added and ultrasonically stirred for 30 min, placed in an oil bath at 120℃ and stirred to react, and 0.5 parts by weight of sulfuric acid catalyst are added under stirring and reacted for 6 h, cooled to room temperature, filtered, washed with ethanol and deionized water, then washed with saturated sodium bicarbonate and deionized water until neutral, and finally washed three times with ethanol and acetone in sequence, and dried at 80℃ to obtain modified cellulose.

[0053] Example 5:

[0054] An ecological water treatment process, in which all other steps are the same as in Example 2, except that:

[0055] In this embodiment, the preparation method of the modified cellulose / sepiolite composite filler is as follows:

[0056] Modified cellulose was dissolved in a frozen 0.1 mol / L sodium hydroxide aqueous solution to prepare a 10 wt% cellulose solution. The cellulose was completely dispersed and dissolved using a high-speed homogenizer at 18,000 rpm for 5 min. Then, sepiolite was added to the cellulose solution at a mass ratio of 1:1, and the mixture was uniformly dispersed using a high-speed homogenizer at 15,000 rpm for 5 min to obtain a mixture. The mixture was then added dropwise to a coagulation bath containing 1 mol / L hydrochloric acid solution using a syringe and magnetically stirred to obtain a cellulose / sepiolite composite filler.

[0057] Example 6:

[0058] An ecological water treatment process is described, with all other steps being the same as in Example 2. The difference from Example 2 is that in step 1, the amount of nutrient solution used in the fluidized bed biofilm reactor is 20 g / L, and the nutrient solution includes 0.5 parts by weight of disodium hydrogen phosphate, 0.008 parts by weight of ammonium sulfate, 0.05 parts by weight of ammonium glycyrrhizate, 10 parts by weight of calcium gluconate, 5 parts by weight of urea, 1 part by weight of isomaltulose, 0.05 parts by weight of magnesium sulfate, and 0.05 parts by weight of N-formyl-L-aspartic-L-phenylalanine methyl ester.

[0059] Example 7:

[0060] An ecological water treatment process is described, with all other steps being the same as in Example 6. The difference from Example 6 is that in step 1, the amount of nutrient solution used in the fluidized bed biofilm reactor is 20 g / L, and the nutrient solution includes 0.5 parts by weight of disodium hydrogen phosphate, 0.008 parts by weight of ammonium sulfate, 0.05 parts by weight of ammonium glycyrrhizate, 10 parts by weight of calcium gluconate, 5 parts by weight of urea, 1 part by weight of isomaltulose, 0.05 parts by weight of magnesium sulfate, and 0.1 parts by weight of N-formyl-L-aspartic-L-phenylalanine methyl ester.

[0061] Example 8:

[0062] An ecological water treatment process is described, with all other steps being the same as in Example 6. The difference from Example 6 is that in step 1, the amount of nutrient solution used in the fluidized bed biofilm reactor is 20 g / L, and the nutrient solution includes 0.5 parts by weight of disodium hydrogen phosphate, 0.008 parts by weight of ammonium sulfate, 0.05 parts by weight of ammonium glycyrrhizate, 10 parts by weight of calcium gluconate, 5 parts by weight of urea, 1 part by weight of isomaltulose, 0.05 parts by weight of magnesium sulfate, and 0.15 parts by weight of N-formyl-L-aspartic-L-phenylalanine methyl ester.

[0063] Comparative Example 1:

[0064] An ecological water treatment process is described, with all other steps being the same as in Example 1. The difference from Example 1 is that in step 1, the cellulose / sepiolite composite packing is replaced with commercially available polypropylene suspended packing.

[0065] Experimental Example 1:

[0066] 1. Determination of Infrared Spectroscopy of Modified Cellulose

[0067] This experiment used the potassium bromide tableting method to treat cotton fibers before and after modification. The mass ratio of the sample to potassium bromide was 1:100, and then infrared scanning analysis was performed in the range of 400-4000 cm⁻¹. -1 .

[0068] Figure 1 The images show the infrared spectra of cellulose before and after modification in Example 2. Figure 1 It can be seen that cellulose is at 3365.2 cm. -1 The characteristic absorption peak near the 1034.7 cm⁻¹ is due to the stretching vibration of -OH. -1 The characteristic absorption peaks nearby are due to the stretching vibrations of COC; while in the infrared spectrum of modified cellulose, the peak at 3550.6 cm⁻¹ is... -1 The characteristic absorption peak appearing nearby is due to the stretching vibration of the -OH group in the carboxyl group; at 1753.8 cm⁻¹ -1 The characteristic absorption peak appearing nearby is due to the stretching vibration of C=O in the carboxyl group; at 1653.2 cm⁻¹ -1 The characteristic absorption peak appearing nearby is due to the stretching vibration of C=C; at 1376.9 cm⁻¹ -1 The characteristic absorption peaks that appear nearby are due to the stretching vibration of CN; therefore, it can be concluded that modified cellulose is obtained by modifying cotton cellulose with 5-benzyloxytryptamine.

[0069] 2. Determination of the morphology and structure of modified cellulose / sepiolite composite filler

[0070] Using a scanning electron microscope at 20kV, the sample was cut open to observe its internal pore structure. After gold sputtering, SEM testing was performed.

[0071] Figure 2 This is a cross-sectional SEM image of the cellulose / sepiolite composite filler in Example 1; Figure 3 This is a cross-sectional SEM image of the modified cellulose / sepiolite composite filler in Example 2; from Figure 2 It can be seen that the internal structure of the cellulose / sepiolite composite filler has many pores of different shapes, unevenly distributed, and of varying sizes. Dissolved cellulose can be inserted into the sepiolite structure; Figure 3It can be seen that the modified cellulose / sepiolite composite filler has a large number of pores in its internal structure, and the pores are evenly distributed, which is conducive to the adsorption of pollutants in ecological water.

[0072] Experimental Example 2:

[0073] Water sample pretreatment: Collect 500 mL of ecological water sample, filter it through a 0.45 μm fiber membrane to remove large particulate impurities, add 0.6 g / L Na2EDTA to eliminate the influence of metal ions in the water, add 0.25 g / L sodium sulfite to eliminate the influence of residual chlorine in the water, adjust the pH of the sample to 3.0 with phosphoric acid solution, store at 4℃, and avoid light. Complete the determination of antibiotics within 48 hours and the determination of organic matter within 1 month.

[0074] 1. Determination of antibiotic residue removal rate in ecological water treatment process

[0075] This experiment determined the removal rates of four antibiotics: tetracycline, norfloxacin, oxytetracycline, and dehydrated erythromycin. Solid-phase extraction-ultra-high performance liquid chromatography-tandem mass spectrometry (SPE-ULHPLC-MS / MS) was used for determination, and MassLynx V4.1 software was used to analyze the concentrations of each antibiotic.

[0076] Accurately weigh 10 mg of various antibiotic standards into a 10 mL volumetric flask, dilute with methanol solution to a final volume of 1.00 mg / mL, and store sealed and protected from light at -4°C. Before use, allow to return to room temperature and shake well. Take an appropriate amount of the standard solution and dilute with a 1:1 methanol-water solution to the required concentration. The dehydrated erythromycin standard solution is prepared by adjusting the pH of the erythromycin standard solution to 3.0 with 2.5 mol / L sulfuric acid and storing at room temperature for 6 hours.

[0077] To determine the antibiotic concentration in water samples, the solid-phase extraction column was activated and stabilized sequentially with 5 mL of acetone, 5 mL of methanol, and 5 mL of ultrapure water before use. The water sample was then filtered through the HLB extraction column at a rate of 3.5 mL / min. After all samples had passed through the column, it was rinsed with 10 mL of ultrapure water to remove impurities. After vacuum drying, the target analytes were eluted with methanol. The eluent was dried under nitrogen gas at 40°C in a water bath, and then brought to a final volume of 0.5 mL with 5% methanol aqueous solution. Analysis was performed using UPLC-MS / MS. The concentrations of various antibiotics in the influent water samples are shown in Table 1.

[0078] Item Tetracycline Norfloxacin Oxytetracycline Dehydrated erythromycin Concentration (ng / L) 12.74 28.35 11.82 379.15

[0079] The concentrations (ng / L) of various antibiotics in the water samples were detected, and the removal rates were calculated as shown in Table 2.

[0080] Test group Tetracycline Norfloxacin Oxytetracycline Dehydrated erythromycin Example 1 7.36 5.06 3.27 41.65 Example 2 3.72 2.15 1.19 17.28 Example 3 4.16 2.36 1.27 16.49 Example 4 4.07 2.21 1.24 18.12 Example 5 3.86 2.19 1.18 17.64 Example 6 3.69 2.08 1.18 10.39 Example 7 3.53 1.95 1.19 10.07 Example 8 3.66 2.12 1.16 10.15 Comparative Example 1 8.71 13.95 6.83 92.62

[0081] As shown in Table 2, in Example 1, the concentration of tetracycline in the effluent sample was below 7.5 ng / L, with a removal rate above 42%; the concentration of norfloxacin was below 5.1 ng / L, with a removal rate above 82%; the concentration of oxytetracycline was below 3.3 ng / L, with a removal rate above 72%; and the concentration of dehydrated erythromycin was below 42.7 ng / L, with a removal rate above 88.5%. In Examples 2-5, the concentration of tetracycline in the effluent sample was below 4.2 ng / L, with a removal rate above 67%; the concentration of norfloxacin was below 2.4 ng / L, with a removal rate above 91.5%; the concentration of oxytetracycline was below 1.3 ng / L, with a removal rate above 89%; and the concentration of dehydrated erythromycin was below 17.5 ng / L, with a removal rate above 95%. Comparing Example 1 and Example 2, the removal rates of tetracycline, norfloxacin, oxytetracycline, and dehydrated erythromycin in Example 2 were all higher than those in Example 1, indicating that the use of... 5-Benzyloxytryptamine modified cotton cellulose, combined with sepiolite to prepare a composite filler, was used in the treatment process of ecological water. It improved the removal rate of antibiotics such as tetracycline, norfloxacin, oxytetracycline, and dehydrated erythromycin, achieving the purpose of purifying water quality. In Examples 6-8, the removal rates of tetracycline, norfloxacin, oxytetracycline, and dehydrated erythromycin were higher than 70.9%, 92%, 89.5%, and 97%, respectively. Comparing Examples 2 and Examples 6-8, the removal rates of tetracycline, norfloxacin, and dehydrated erythromycin in Examples 6-8 were higher than those in Example 2, while the removal rate of oxytetracycline was not significantly different from that in Example 2. This indicates that the addition of N-formyl-L-aspartic-L-phenylalanine methyl ester to the nutrient solution further improved the removal rates of tetracycline, norfloxacin, and dehydrated erythromycin, with a more significant improvement in the removal rate of dehydrated erythromycin, while having almost no effect on the removal rate of oxytetracycline. Comparing Examples 1-8 with Comparative Example 1, the removal rates of tetracycline, norfloxacin, oxytetracycline, and dehydrated erythromycin in Examples 1-8 were all higher than those in Comparative Example 1. This indicates that the technical solution of the present invention has a better antibiotic removal effect on ecological water.

[0082] 2. Determination of Organic Matter Removal Rate in Ecological Water Treatment Processes

[0083] The organic compounds determined in this experiment were polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Solid-phase extraction was performed first. PAH purification was achieved using a silica gel / alumina composite chromatography column, while PCB purification was performed using a Floris column. The purified PAHs and PCBs were then concentrated and brought to a final volume. All experimental parameters were set according to standard procedures.

[0084] Polycyclic aromatic hydrocarbons (PAHs) were determined by GC / MS. The test conditions were as follows: DB capillary column (60 m × 0.25 mm × 0.25 μm), high-purity helium as carrier gas; GC conditions: programmed temperature ramp, initial temperature 50 °C, hold for 2 min; then first ramp at 15 °C / min to 200 °C, hold for 2 min; second ramp at 5 °C / min to 250 °C, hold for 2 min; finally, third ramp at 2 °C / min to 290 °C, hold for 15 min; injection port temperature 280 °C; constant flow mode, flow rate 1.5 mL / min, linear velocity 26 cm / sec, splitless injection of 1 μL. Gas chromatography-mass spectrometry transfer line temperature 300 °C, solvent delay 10 min.

[0085] Polychlorinated biphenyls (PCBs) were determined by GC-μECD; the chromatographic column was an HP-5 quartz capillary column (30m × 0.32mm × 0.25μm), and the carrier gas was high-purity nitrogen. GC conditions: programmed temperature ramp, initial temperature 60℃, hold for 2 min, ramp at 10℃ / min to 180℃, hold for 10 min, then ramp at 5℃ / min to 250℃; the injection port temperature was 280℃; the injection port was in constant flow mode, with a flow rate of 2.0 mL / min, a linear velocity of 50 cm / sec, and a splitless injection of 1 μL; the detector temperature was 300℃.

[0086] According to the Urban Water Supply Quality Standard (CJ / T 206-2005), the limit for total polycyclic aromatic hydrocarbons (including benzo[a]fluoranthene, dibenzo[a]anthene, benzo[a]pyrene, etc.) is 2000 ng / L, and the limit for benzo[a]pyrene is 10 ng / L. According to the Surface Water Environmental Quality Standard (GB3838-2002), the limit for polychlorinated biphenyls (PCBs) concentration in surface water sources for drinking water is 20 ng / L.

[0087] The concentrations (ng / L) of each substance in the influent were measured and are shown in Table 3.

[0088] Item Total concentration of polycyclic aromatic hydrocarbons Benzo pyrene Total concentration of polychlorinated biphenyls Concentration (ng / L) 501.4 12.5 65.7

[0089] The concentration (ng / L) of each substance in the water sample was detected, and the removal rate was calculated as shown in Table 4.

[0090] Test group Total concentration of polycyclic aromatic hydrocarbons Benzo pyrene Total concentration of polychlorinated biphenyls Example 1 63.9 5.7 11.2 Example 2 41.7 2.9 5.5 Example 3 43.1 3.6 6.2 Example 4 42.5 3.2 5.9 Example 5 41.3 3.7 5.3 Example 6 32.8 2.9 4.8 Example 7 35.2 3.1 4.3 Example 8 34.7 2.8 5.1 Comparative Example 1 103.7 8.3 19.7

[0091] As shown in Table 4, in Example 1, the total concentration of polycyclic aromatic hydrocarbons (PAHs) was below 64 ng / L, with a removal rate above 87%. Specifically, the concentration of benzo[a]pyrene was below 6 ng / L, with a removal rate above 52%, and the total concentration of polychlorinated biphenyls (PCBs) was below 11.5 ng / L, with a removal rate above 82.5%. In Examples 2-5, the total concentration of PAHs was below 44 ng / L, with a removal rate above 91%. Specifically, the concentration of benzo[a]pyrene was below 4 ng / L, with a removal rate above 68%, and the total concentration of PCBs was below 6.5 ng / L, with a removal rate above 90%, far exceeding the national water quality standards. Comparing Example 1 and Example 2, the removal rates of PAHs (benzo[a]pyrene) and PCBs in Example 2 were higher than in Example 1. This indicates that using 5-benzyloxytryptamine-modified cotton cellulose, combined with sepiolite to prepare a composite filler, and applying it to the treatment of ecological water... In the treatment process, it improves the removal rate of polycyclic aromatic hydrocarbons (benzo[a]pyrene) and polychlorinated biphenyls (PCBs), effectively removing toxic organic substances from ecological water. Comparing Examples 2 and Examples 6-8, the total concentrations of polycyclic aromatic hydrocarbons and PCBs in Examples 6-8 are lower than those in Example 2, meaning the removal rates are higher than those in Example 1. However, the removal rate of benzo[a]pyrene in polycyclic aromatic hydrocarbons is not significantly different from that in Example 2. This indicates that adding N-formyl-L-aspartic-L-phenylalanine methyl ester to the nutrient solution further improves the removal rate of polycyclic aromatic hydrocarbons and PCBs, but has no significant effect on the removal rate of benzo[a]pyrene in polycyclic aromatic hydrocarbons. Comparing Examples 1-8 and Comparative Example 1, the concentrations of polycyclic aromatic hydrocarbons and PCBs in Examples 1-8 are higher than those in Comparative Example 1. This shows that using the technical solution of this invention to treat ecological water results in better removal of toxic organic substances.

[0092] The conventional operations in the operation steps of this invention are well known to those skilled in the art and will not be described in detail here.

[0093] The above embodiments are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all equivalent technical solutions also fall within the scope of this invention, and the patent protection scope of this invention should be defined by the claims.

Claims

1. An ecological water treatment process, comprising the following steps: Step 1: treating with a fluidized bed biofilm reactor device, adding cellulose / sepiolite composite filler and nutrient solution to the fluidized bed biofilm reactor; Step 2: inoculating the fluidized bed biofilm reactor with activated sludge and performing aeration reaction; Step 3: operating the fluidized bed biofilm reactor in a continuous ecological water feeding mode, performing aeration reaction, adjusting the pH in the system to 6.3-7.8, continuously recycling sludge from the secondary sedimentation tank of the fluidized bed biofilm reactor at a sludge recycle ratio of 150-200%, and continuously operating for 48-72 h; Step 4: adjusting the dissolved oxygen in the system to 0.55-0.85 mg / L according to the biofilm thickness on the surface of the filler for water treatment in the fluidized bed biofilm reactor, adjusting the pH in the system to 6.3-7.8, continuously recycling sludge from the secondary sedimentation tank of the fluidized bed biofilm reactor at a sludge recycle ratio of 150-200%, and continuously operating for 48-72 h to obtain effluent water; the composite filler is a modified cellulose / sepiolite composite material, the filling ratio of the modified cellulose / sepiolite composite filler in the fluidized bed biofilm reactor is 35-40%, and the amount of the nutrient solution is 15-40 g / L; the modified cellulose is 5-benzyloxytryptamine acid modified cotton cellulose.

2. An ecological water treatment process according to claim 1, characterized in that: the nutrient solution comprises disodium hydrogen phosphate, ammonium sulfate, ammonium glycyrrhizate, calcium gluconate, urea, isomaltulose, and magnesium sulfate.

3. An ecological water treatment process according to claim 2, characterized in that: In terms of weight parts, the disodium hydrogen phosphate in the nutrient solution is 0.5-1.5 parts, the ammonium sulfate is 0.005-0.01 parts, the ammonium glycyrrhizate is 0.05-0.1 parts, the calcium gluconate is 10-20 parts, the urea is 5-10 parts, the isomaltulose is 1-3 parts, and the magnesium sulfate is 0.05-0.1 parts.

4. An ecological water treatment process according to claim 1, characterized by the fact that: the activated sludge is aerobic activated sludge, and the amount of the activated sludge in the fluidized bed biofilm reactor is 2.5-7.5 g / L.

5. An ecological water treatment process according to claim 1, characterized by the fact that: the removal rate of polycyclic aromatic hydrocarbons in the ecological water is higher than 91%, and the removal rate of polychlorinated biphenyl is higher than 90%.

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