Electron beam irradiation solid waste treatment method

Abstract

The invention provides an electron beam irradiation solid waste treatment method, and particularly provides a steroid hormone mushroom dreg treatment method which comprises the following steps: 1) performing first mixing treatment on methanol and to-be-treated steroid hormone mushroom dregs to obtain a first mixed solution; 2) adding calcium chloride into the first mixed solution to obtain a second mixed solution; and 3) carrying out ionizing radiation treatment on the second mixed solution so as to remove steroid hormone substances in the steroid hormone mushroom dregs. According to the method, steroid androgen pollutants in the mushroom dregs can be efficiently removed.

Description

Technical Field

[0001] The present invention belongs to the technical field of solid waste treatment, and particularly relates to a method for treating solid waste by electron beam irradiation. Background Art

[0002] Steroid hormones refer to hormone drugs containing a steroid structure in the molecule. Its basic structure contains a cyclopentane polyhydrophenanthrene nucleus and three side chains. The nucleus is like the character "field", and the three side chains are like the character "chuan", so the character "steroid" is used to represent this kind of compound vividly. Steroid hormones mainly include sex hormones (estrogen and androgen), adrenal cortical hormones and anabolic hormones. They are the second largest class of drugs after antibiotics and are widely used in the medical field. Among them, androgens such as androstenedione and 9α-hydroxyandrostenedione are key intermediates for the synthesis of various steroid hormone drugs, and the market scale is huge. It is estimated that the global market scale of androstenedione will reach 210 million US dollars by 2025.

[0003] The production methods of steroid androgens mainly include chemical synthesis method and microbial fermentation method. The chemical synthesis process is complex, with high raw material costs, low yields, and serious environmental pollution, and has been gradually phased out. At present, the microbial fermentation method has become the mainstream technology for the production of steroid hormone drugs. After fermentation is completed and steroid hormone drugs are extracted, a large amount of bacterial residue waste remains. The safe disposal and effective utilization of steroid hormone pharmaceutical waste have become one of the important factors restricting the profit growth and production capacity expansion of enterprises.

[0004] Steroid hormones are a class of important endocrine disrupting chemicals (EDCs). Even at extremely low concentrations, they can cause hermaphroditism and reproductive system disorders in aquatic organisms, causing significant harm to the ecological environment and human health. Together with persistent organic pollutants, antibiotics, and microplastics, EDCs are the "new pollutants" that have attracted extensive international attention.

[0005] The main components of steroid hormone bacterial residues are mycelia, culture media, and residual steroid hormones. The pollution source comes from the residual steroid hormones. If they can be removed from the bacterial residues, the harmless bacterial residues can be made into fertilizers for resource reuse, thus solving the problems of treatment and disposal of steroid hormone bacterial residues. Steroid androgens have good thermal stability. Even under high temperature conditions of 165 °C, the structures of androgens such as androstenedione, 9α-hydroxyandrostenedione, and testosterone basically remain unchanged. Therefore, the pyrolysis process for treating antibiotic bacterial residues commonly used in pharmaceutical factories at present is not applicable to the treatment of steroid hormone bacterial residues.

[0006] Advanced oxidation technologies such as ultraviolet light catalysis and Fenton oxidation have good degradation and removal effects on steroid hormones in wastewater, but are less effective in removing steroid hormones from bacterial residues. Bacterial residues are viscous solid-liquid mixtures, and these conventional methods are difficult to penetrate into the internal reaction of bacterial residues. Moreover, steroid hormones are strongly hydrophobic compounds with a high octanol-water partition coefficient (K ow ). Under the combined action of hydrophobic partitioning and electrostatic interactions, steroid hormones are firmly adsorbed and bound to the solids of bacterial slag cells, making it difficult for them to react with active particles such as hydroxyl radicals in water.

[0007] Therefore, there is an urgent need for a method for effectively treating steroid hormone bacterial residues. Summary of the invention

[0008] The present invention aims to solve one of the technical problems in the related art at least to a certain extent. To this end, one object of the present invention is to provide a steroid hormone fungus residue treatment method for efficiently removing steroid androgen contaminants in fungus residue.

[0009] In one aspect of the present invention, the present invention provides a method for treating steroid hormone bacterial residues. According to an embodiment of the present invention, the method comprises:

[0010] 1) performing a first mixing treatment on methanol and the steroid hormone bacterial residue to be treated to obtain a first mixed liquid;

[0011] 2) adding calcium chloride to the first mixed solution to obtain a second mixed solution;

[0012] 3) The second mixed liquid is subjected to ionizing radiation treatment to remove the steroid hormone substances in the steroid hormone bacterial residue. This method can effectively remove steroid androgen contaminants in the bacterial residue.

[0013] According to an embodiment of the present invention, the above method may further include at least one of the following additional technical features:

[0014] According to an embodiment of the present invention, the dosage of the methanol solution is 2% to 4% (methanol concentration / residual steroid hormone concentration).

[0015] According to an embodiment of the present invention, the dosage of calcium chloride is 10% to 20% (calcium chloride concentration / residual steroid hormone concentration).

[0016] According to an embodiment of the present invention, the ionizing radiation treatment is performed by subjecting the second mixed liquid to ionizing radiation treatment using an electron beam.

[0017] According to an embodiment of the present invention, the irradiation absorbed dose of the electron beam is 25 kGy to 50 kGy.

[0018] According to an embodiment of the present invention, the steroid hormone bacterial residue is bacterial residue containing residual steroid hormones produced during the production process of steroid hormones.

[0019] According to an embodiment of the present invention, the steroid hormone is androstenedione or 9α-hydroxyandrostenedione.

[0020] According to an embodiment of the present invention, the concentration of androstenedione remaining in the steroid hormone bacterial residue is 200 mg / kg.

[0021] According to an embodiment of the present invention, the concentration of residual 9α-hydroxyandrostenedione in the steroid hormone bacterial residue is 500 mg / kg.

[0022] According to an embodiment of the present invention, the first mixing process is performed by vortex oscillation.

[0023] According to an embodiment of the present invention, the second mixing process is performed by vortex oscillation.

[0024] In another aspect of the present invention, the present invention also provides a method for treating steroid hormone bacterial residues. According to an embodiment of the present invention, the method is as follows:

[0025] 1) Add a certain concentration of methanol to the steroid hormone bacterial residue, vortex and shake to mix evenly;

[0026] 2) adding a certain concentration of calcium chloride to the above mixture, vortexing and mixing evenly;

[0027] 3) sending the mixture to an irradiation chamber of an electron accelerator, and irradiating the mixture with an electron beam to degrade and remove the steroid hormone substances in the fungus residue. This method can effectively remove steroid androgen contaminants in the fungus residue.

[0028] According to an embodiment of the present invention, the above method may further include at least one of the following additional technical features:

[0029] According to an embodiment of the present invention, the electron beam is a dense high-speed electron flow with an extremely high energy density, which can penetrate into the internal reaction of the fungus residue. Methanol can combine with the steroid hormone molecules adsorbed on the bacterial cells through hydrophobic interactions, remove them from the fungus residue solid, and release them into the solution. Calcium ions can replace the steroid hormone molecules that have been adsorbed on the fungus residue solid through ion exchange. Under the above-mentioned synergistic effect, the steroid hormones are removed from the fungus residue solid and released into the solution. Under the combined action of the direct radiation of the high-energy electron beam, the active particles such as hydroxyl free radicals generated by electron-excited water molecules, and the chlorine free radicals generated by irradiation-excited chloride ions, the steroid hormone pollutants in the fungus residue are efficiently degraded and removed.

[0030] According to an embodiment of the present invention, the steroid hormone bacterial residue is bacterial residue containing residual steroid hormones produced in the production process of steroid hormones, and the steroid hormone is androstenedione (AD) or 9α-hydroxyandrostenedione (OHAD).

[0031] According to an embodiment of the present invention, the dosage of the methanol solution is: 2% to 4% (methanol concentration / residual steroid hormone concentration).

[0032] According to an embodiment of the present invention, the dosage of calcium chloride is: 10% to 20% (calcium chloride concentration / residual steroid hormone concentration).

[0033] According to an embodiment of the present invention, the irradiation absorbed dose of the electron beam is 25 kGy to 50 kGy.

[0034] According to an embodiment of the present invention, methanol and calcium chloride work together to remove steroid hormone molecules from the solid cells of the fungus residue through hydrophobic interaction and cation exchange; the acidic environment of the steroid hormone fungus residue (pH = 4.7-5.7) helps to produce chlorine free radicals during irradiation, strengthens the removal of steroid hormones in the fungus residue, and the removal rate of steroid hormones can reach more than 99%. In the method provided by the embodiment of the present invention, electron beam irradiation is carried out at room temperature, which is easy to achieve large-scale engineering applications. It can be seen that the method provided by the implementation of the present invention is efficient and widely applicable. It can be applied to the treatment of steroid hormone fungus residue and has broad application prospects in the field of hazardous solid waste treatment.

[0035] According to an embodiment of the present invention, the electron beam is generated by an electron accelerator and is a dense high-speed electron flow with extremely high energy. Electron beam irradiation is an ionizing irradiation technology. After water molecules are excited by high-energy electron beam radiation, they produce strong oxidizing hydroxyl radicals (·OH) and strong reducing hydrated electrons (e aq - ) and hydrogen free radicals (·H) and other active particles (as shown in Formula 1, the values ​​in brackets are the radiochemical yield G value of each active particle). Steroid hormone molecules can undergo oxidation-reduction reactions with these active particles and be degraded.

[0036]

[0037] According to the embodiments of the present invention, the degradation rate of steroid hormones such as AD and OHAD in aqueous solution by electron beam irradiation is relatively high, but the degradation rate of steroid hormones in the solid waste of bacterial residue is significantly reduced. The adsorption of steroid hormones by bacterial cells significantly affects their irradiation degradation efficiency. Steroid hormones are strongly hydrophobic compounds with high octanol-water partition coefficients (such as logK of AD). ow is 2.75, the logK of OHAD ow 3.98). Under the combined action of hydrophobic partitioning and electrostatic interactions, steroid hormones are firmly adsorbed and bound to the solid cells of the fungus residue, and it is difficult to react with active particles such as hydroxyl radicals in water. If the steroid hormone molecules can be removed from the solid fungus residue and their concentration in the supernatant can be increased, it is expected to improve the irradiation degradation efficiency of steroid hormones in the fungus residue.

[0038] According to the embodiment of the present invention, methanol is an organic substance that is completely miscible with water and is often used as a solubilizer for organic substances. Methanol can bind to steroid hormone molecules adsorbed on bacterial cells through hydrophobic interactions, remove them from the bacterial residue solids, and release them into the supernatant. In addition, in the acidic environment of the bacterial residue, most of the steroid hormone molecules exist in the form of positively charged ions, and the metal cation Ca 2+ The steroid hormone molecules adsorbed on the solid fungus residue can be replaced by ion exchange, further increasing their concentration in the supernatant and strengthening the collision and reaction with active particles such as hydroxyl radicals in the solution. Furthermore, under the acidic conditions of fungus residue, chloride ions can produce chlorine free radicals through the following reaction. Chlorine free radicals have a high reaction rate constant with steroid hormone molecules (on the order of 10 10 L / mol s). Steroid hormone molecules are efficiently degraded under the combined action of active particles such as hydroxyl free radicals, chlorine free radicals, and hydrated electrons.

[0039] Cl - + ·OH→ClOH ·- k = 4.3 × 10 9 L / mols (2)

[0040] ClOH ·- +H + →Cl·+H2O k=2.1×10 9 L / mols (3) DETAILED DESCRIPTION

[0041] The embodiments described below are exemplary and intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0042] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0043] The present invention is described below with reference to specific embodiments. It should be noted that these embodiments are merely illustrative and do not limit the present invention in any way.

[0044] Example 1

[0045] AD fermentation residue was obtained from a pharmaceutical company in Hebei Province, my country. Its moisture content was 79%, pH value was 5.6, total solid (TS) content was 212 g / kg, volatile solid (VS) / TS ratio was 85%, and residual AD concentration was about 200 mg / kg. Methanol was commercially available analytical grade. Calcium chloride was commercially available analytical grade.

[0046] Weigh about 10g of AD fermentation residue, add 4mg / L (2%), 8mg / L (4%), 12mg / L (6%) of methanol respectively, and vortex to mix evenly. Weigh about 10g of AD fermentation residue, first add 4mg / L of methanol, then add 10mg / L (5%), 20mg / L (10%), 40mg / L (20%) of calcium chloride respectively, and vortex to mix evenly. Put the evenly mixed residue sample into a sample bag and send it to the irradiation room of the electron accelerator by a conveyor belt for irradiation. Pure residue samples without methanol and calcium chloride and residue samples with calcium chloride added alone are irradiated at the same time for comparison.

[0047] By controlling the electron beam intensity and the sample transmission speed, different irradiation absorbed doses of 10 kGy, 25 kGy, and 50 kGy were obtained. The detection index was the concentration of steroid hormone AD in the fungus residue before and after electron beam irradiation.

[0048] The residual AD in the fungus residue was first extracted with acetonitrile and then detected by liquid chromatography.

[0049] The AD extraction method in the fungus residue is as follows: take about 0.2g of fungus residue and put it in a 15mL polypropylene centrifuge tube, add 5mL of acetonitrile, vortex for 3min, and perform ultrasound-assisted extraction for 20min. Centrifuge at 10000rpm for 10min, take the supernatant and filter it with a 0.22μm filter membrane, and dilute the filtered solution to an appropriate multiple for high performance liquid chromatography detection.

[0050] The high performance liquid chromatograph used was Agilent 1200, the chromatographic column was XDB-C18 reverse phase column, the column temperature was 30°C, the mobile phase was 0.1% formic acid aqueous solution and acetonitrile (mixing ratio 30:70), the detector was an ultraviolet detector, and the AD detection wavelength was 245nm.

[0051] The removal rate of AD in the fungus residue under different absorption doses, methanol and calcium chloride dosages is shown in Table 1. It can be seen that when the irradiation absorption dose is 10kGy, the AD removal rate can reach 79%, but as the absorption dose increases further, the increase in the AD removal rate is small. When the absorption dose is 50kGy, the AD removal rate is 90%, and a relatively high concentration of AD (about 20mg / L) still remains in the fungus residue.

[0052] When the amount of methanol added is 2% and 4%, the removal efficiency of AD can be significantly improved. When the absorbed dose is 50kGy, the AD removal rate can reach 93% to 96%. However, if the methanol dose is too high (6%), the removal rate of AD will decrease. Methanol can react with hydroxyl radicals generated by irradiation of water molecules. If the concentration is too high, the quenching effect on hydroxyl radicals will be greater than its promoting effect of strengthening AD desorption and dissolution, which will reduce the removal efficiency of AD.

[0053] When the amount of methanol added is 2% to 4%, and calcium chloride is added, the removal efficiency of AD is further improved. When the amount of methanol added is 2% to 4%, the amount of calcium chloride added is 20%, and the absorbed dose is 25 to 50 kGy, the removal rate of AD can reach more than 99%. The addition of calcium chloride alone also has a certain promoting effect on AD degradation. When the amount of calcium chloride added is 20% and the absorbed dose is 50 kGy, the AD removal rate is 92%.

[0054] Table 1 Removal rate of AD in fungus residue under different experimental conditions (%)

[0055]

[0056] Example 2

[0057] OHAD fermentation residue was obtained from a pharmaceutical company in Hubei Province, my country. Its moisture content was 37%, pH value was 4.6, total solid (TS) content was 332 g / kg, volatile solid (VS) / TS ratio was 99%, and residual OHAD concentration was about 500 mg / kg. Methanol was commercially available analytical grade. Calcium chloride was commercially available analytical grade.

[0058] Weigh about 10g of OHAD fermentation residue, add 10mg / L (2%), 20mg / L (4%), 30mg / L (6%) of methanol respectively, and vortex to mix evenly. Weigh about 10g of OHAD fermentation residue, first add 10mg / L of methanol, then add 25mg / L (5%), 50mg / L (10%), 100mg / L (20%) of calcium chloride respectively, and vortex to mix evenly. Put the mixed residue sample into a sample bag and send it to the irradiation room of the electron accelerator by a conveyor belt for irradiation. Pure residue samples without methanol and calcium chloride and residue samples with calcium chloride added alone are irradiated at the same time for comparison.

[0059] By controlling the electron beam intensity and the sample transmission speed, different irradiation absorbed doses of 10 kGy, 25 kGy, and 50 kGy were obtained. The detection index was the concentration of steroid hormone OHAD in the fungus residue before and after electron beam irradiation.

[0060] The residual OHAD in the fungus residue was first extracted with acetonitrile and then detected by liquid chromatography.

[0061] The OHAD extraction method in the fungus residue is as follows: take about 0.2g of fungus residue and put it in a 15mL polypropylene centrifuge tube, add 5mL of acetonitrile, vortex for 3min, and perform ultrasonic assisted extraction for 20min. Centrifuge at 10000rpm for 10min, take the supernatant and filter it with a 0.22μm filter membrane, and dilute the filtered solution to an appropriate multiple for high performance liquid chromatography detection.

[0062] The high performance liquid chromatograph used was Agilent 1200, the chromatographic column was XDB-C18 reverse phase column, the column temperature was 30°C, the mobile phase was 0.1% formic acid aqueous solution and acetonitrile (mixing ratio 30:70), the detector was an ultraviolet detector, and the OHAD detection wavelength was 254nm.

[0063] The removal rate of OHAD in the fungus residue under different absorption doses, methanol and calcium chloride dosages is shown in Table 2. It can be seen that when the irradiation absorption dose is 10 kGy, the OHAD removal rate can reach 74%, but as the absorption dose increases further, the increase in the OHAD removal rate is small. When the absorption dose is 50 kGy, the OHAD removal rate is 88%, and a relatively high concentration of OHAD (about 60 mg / L) still remains in the fungus residue.

[0064] When the amount of methanol added is 2% to 4%, the removal efficiency of OHAD can be significantly improved. When the absorbed dose is 50kGy, the OHAD removal rate can reach 90% to 95%. However, if the methanol dose is too high (6%), the removal rate of OHAD will decrease. Methanol can react with hydroxyl radicals generated by irradiation of water molecules. If the concentration is too high, the quenching effect on hydroxyl radicals is greater than its promoting effect on strengthening the dissolution of OHAD, which reduces the removal efficiency of OHAD.

[0065] When the amount of methanol added is 2% to 4%, and calcium chloride is added, the removal rate of OHAD is further improved. When the amount of methanol added is 4%, the amount of calcium chloride added is 20%, and the absorbed dose is 25 to 50 kGy, the removal rate of OHAD can reach more than 99%. The addition of calcium chloride alone has a certain promoting effect on the degradation of OHAD. When the amount of calcium chloride added is 20% and the absorbed dose is 50 kGy, the OHAD removal rate is 91%.

[0066] Table 2 Removal rate of OHAD in fungus residue under different experimental conditions (%)

[0067]

[0068] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

Claims

1. A method for treating steroid hormone bacterial residues, characterized in that: include: 1) performing a first mixing treatment on methanol and the steroid hormone bacterial residue to be treated to obtain a first mixed liquid; 2) adding calcium chloride to the first mixed solution to obtain a second mixed solution; 3) treating the second mixed solution with ionizing radiation to remove steroid hormone substances in the steroid hormone bacterial residue.

2. The processing method according to claim 1, characterized in that: The dosage of the methanol is 2% to 4%.

3. The processing method according to claim 1, characterized in that: The dosage of the calcium chloride is 10% to 20%.

4. The processing method according to claim 1, characterized in that: The ionizing radiation treatment is performed by subjecting the second mixed liquid to ionizing radiation treatment with an electron beam.

5. The processing method according to claim 4, characterized in that: The irradiation absorption dose of the electron beam is 25 kGy to 50 kGy.

6. The processing method according to claim 1, characterized in that: The steroid hormone bacterial residue is bacterial residue containing residual steroid hormones produced during the production process of steroid hormones.

7. The processing method according to claim 1, characterized in that: The steroid hormone is androstenedione or 9α-hydroxyandrostenedione.

8. The processing method according to claim 1, characterized in that: The concentration of androstenedione remaining in the steroid hormone bacterial residue is 200 mg / kg.

9. The processing method according to claim 1, characterized in that: The concentration of residual 9α-hydroxyandrostenedione in the steroid hormone bacterial residue is 500 mg / kg.

10. The processing method according to claim 1, characterized in that: The first mixing process is performed by vortex shaking; Optionally, the second mixing process is performed by vortexing.

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