A method for treating high-salinity wastewater using fungi

Abstract

This invention discloses a method for treating high-salinity wastewater using fungi, comprising: preparing immobilized fungi using cotton thread carriers or related carriers; setting up a fungal-electric coupling device; inoculating the fungi in a high-salinity sterile liquid culture medium and applying different voltages through a DC power supply; treating the high-salinity wastewater using the fungi under carbon source regulation; and treating actual high-salinity wastewater using electrical stimulation in synergistic fungal treatment. This invention has significant environmental friendliness and economic advantages. Compared with existing technologies, this innovative treatment scheme not only reduces the generation of toxic substances but also reduces the use of chemical agents required for subsequent treatment. According to this invention, it features low cost, simple operation, no need for additional chemical inputs, and reduced environmental harm.

Description

Technical Field

[0001] This invention relates to the technical field of wastewater treatment, and in particular to a method for treating high-salt wastewater using fungi. Background Technology

[0002] With industrial development, the types of wastewater discharged are increasing. High-salinity wastewater, characterized by a solid salt concentration exceeding 3.5%, primarily originates from industrial production, chemical processing, and daily life. Improper treatment of this wastewater can cause numerous environmental hazards. First, the discharge of high-salinity wastewater pollutes nearby water bodies, harming aquatic life, causing its death or loss, which in turn severely impacts the ecological environment. Second, high-salinity wastewater exacerbates soil salinization and groundwater pollution, undermining agricultural production and impairing crop growth and quality. Simultaneously, treating high-salinity wastewater is crucial for resource recovery and utilization; therefore, its treatment is essential.

[0003] With increasingly stringent discharge standards for high-salinity wastewater, the treatment of such wastewater must achieve "zero discharge." Currently, the main treatment methods for high-salinity wastewater consist of two aspects: desalination and organic pollutant removal. Desalination involves using evaporation crystallization to crystallize the salts in the wastewater, then recovering or transporting the crystallized salt for further treatment, and reusing the condensate. If the salts can be recovered and reused, the environmental impact will be greatly reduced, thus achieving the goal of "zero discharge." The presence of pollutants reduces the quality of the crystallized salt, especially in the presence of toxic and harmful substances and heavy metals, lowering its recovery value and requiring disposal as hazardous solid waste. Currently, the main methods for treating organic pollutants in high-salinity wastewater include biological treatment and physicochemical treatment (adsorption, coagulation sedimentation, advanced oxidation, etc.). However, single methods face problems such as high energy consumption and limited treatment effectiveness, making it difficult to meet discharge standards. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a method for treating high-salinity wastewater using fungi, which is characterized by low cost, simple operation, no need for additional chemical inputs, and reduced environmental harm. To achieve the above-mentioned objectives and other advantages of the present invention, a method for treating high-salinity wastewater using fungi is provided, comprising:

[0005] A microbial-electric coupling device, comprising a container, high-salt wastewater placed in the container, an anode and a cathode placed in the high-salt wastewater, immobilized fungi placed in the high-salt wastewater, and a DC power supply electrically connected to the anode and the cathode;

[0006] Different voltages are applied to the high-salinity wastewater using the DC power supply;

[0007] The high-salt wastewater is treated by using fungi through carbon source regulation and electrical stimulation, thereby achieving the synergistic treatment of actual high-salt wastewater by electrical stimulation and fungi.

[0008] Compared with existing technologies, the beneficial effects of this invention are as follows: It utilizes fungi to treat high-salt wastewater with complex organic components. The fungi secrete various specific enzymes, such as lignin peroxidase and laccase. These enzymes convert large organic molecules into smaller molecules through redox reactions, ultimately mineralizing them into carbon dioxide and water, effectively degrading complex organic compounds in high-salt wastewater. Under synergistic conditions of microbial-electrical stimulation, appropriate electrical stimulation increases the metabolic rate and level of the fungi. Even under nutrient-poor conditions, the fungi can maintain cell structural stability, helping them to enter the secondary metabolic stage earlier and produce various specific enzymes. This results in higher degradation efficiency for aromatic compounds and significant removal of most metal ions in wastewater. Furthermore, it inhibits the formation of toxic compounds such as chlorobenzene and chlorophenol to a certain extent, reducing the toxicity of high-salt wastewater and decreasing the use of chemical agents in subsequent treatment, thus reducing the burden on subsequent treatment processes. The combined experimental application of electrical stimulation and fungi will provide a more efficient and environmentally friendly solution for the treatment of high-salt wastewater and other industrial wastewater with complex organic components. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of the experimental apparatus for the fungal-electric coupling technology of the method for treating high-salt wastewater according to the present invention;

[0010] Figure 2 The rate at which fungi consume glucose in a culture medium under different voltages is used to illustrate the method for treating high-salt wastewater using fungi according to the present invention.

[0011] Figure 3 The TOC variation trend of the fungal treatment of high-salinity wastewater according to the method of fungal treatment of high-salinity wastewater according to the present invention;

[0012] Figure 4 The removal rate of metal elements in high-salt wastewater by fungi according to the method of treating high-salt wastewater by fungi according to the present invention;

[0013] Figure 5 UV radiation from fungi in the method for treating high-salinity wastewater according to the present invention 254 Trends;

[0014] Figure 6To investigate the changes in organic matter treatment in high-salt wastewater by fungi according to the method of treating high-salt wastewater according to the present invention, parallel factor analysis was performed to analyze the differences among the components. The fluorescence EEM spectrum was divided into five parts: Region I (Ex / Em = 200-250nm / 280-330nm), Region II (Ex / Em = 200-250nm / 330-380nm), Region III and Region IV (Ex / Em = 250-400nm / 330-380nm), and Region V (Ex / Em = 250-400nm / 380-560nm), representing aromatic proteins (APⅠ), aromatic proteins (APⅡ), fulvic acid-like substances (FA), soluble microbial products (SMP), and humic acid-like substances (HA), respectively.

[0015] Figure 1 In the middle: 1. DC power supply; 2. Three-electrode electrolytic cell; 3. Anode; 4. Cathode; 5. Drainage tube; 6. High-salt wastewater; 7. Immobilized fungi. Detailed Implementation

[0016] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0017] like Figure 1 This is a schematic diagram of the experimental apparatus for this invention. This technology is based on fungal biodegradation, comprehensively utilizing electrical stimulation to synergistically degrade actual high-salinity wastewater. Under nutrient-poor conditions, the fungi use their metabolic activities to treat complex organic matter in the high-salinity wastewater, achieving effective removal of various complex organic compounds and reducing wastewater toxicity.

[0018] The fungus used in the following embodiments of the present invention is Trametesversicolor (CICC 14001), a white-rot fungus. It is classified as Polyporaceae and Trametes versicolor, and was purchased from the China Industrial Culture Collection Center. The obtained strain is in the form of slant culture.

[0019] In the following embodiments of the present invention, the high-salt wastewater is selected from petrochemical reverse osmosis concentrate with a salinity of 3.90±0.5% and a pH adjusted to 4.5±0.5.

[0020] Example 1

[0021] A method for treating high-salinity wastewater using fungi includes the following steps:

[0022] Fungi were inoculated into sterile Kirk medium, with the conductivity and salinity approximating that of petrochemical reverse osmosis concentrate by adding NaCl (approximate NaCl concentration of 0.25%). Each medium consisted of 200 ml of this medium. A DC power supply was applied with voltage gradients of 0V, 1V, 2V, 3V, and 4V. The medium was placed in a constant-temperature shaker at 28℃ and 150 rpm for 7 days. The glucose concentration in the medium was measured daily. Specific results are shown below. Figure 2 As shown.

[0023] Depend on Figure 2 It can be seen that the rate of glucose consumption by fungi increases with the increase of voltage in the 1V-3V gradient. The voltage at which the consumption rate is fastest is 3V. At 4V, the glucose consumption rate is still faster than at 0V and 1V, but slower than at 2V and 3V. In summary, 3V is the optimal voltage for fungal growth in high-salt wastewater.

[0024] Example 2

[0025] A method for treating high-salinity wastewater using fungi includes the following steps:

[0026] Immobilized fungi were introduced into high-salinity wastewater, and three carbon source control groups were set up: one group was added with fungi only, without providing an initial carbon source or subsequent carbon source supplementation; another group was provided with 0.5 g / L glucose as the initial carbon source, supplemented daily with concentrated glucose and ammonium tartrate solution to supplement nutrients; and the third group was provided with only 0.5 g / L glucose as the initial carbon source, without further nutrient supplementation. After completion, the wastewater was placed in a constant-temperature shaker with parameters set at 28℃ and 150 rpm for 7 days. The changes in TOC in the wastewater were measured, and the specific results are as follows: Figure 3 As shown.

[0027] Depend on Figure 3 It can be seen that fungi have a clear trend of degrading TOC. R0 reached the highest degradation rate of 34.96% on day 5, while R1 and R2 reached the highest degradation rate of 16.39% and 45.60% on day 3, respectively. In comparison, R2 treatment effect was the best.

[0028] Example 3

[0029] A method for treating high-salinity wastewater using fungi includes the following steps:

[0030] Immobilized fungi in cotton thread were introduced into high-salt wastewater under carbon source regulation and electrocoupling conditions, respectively. The experimental period was set to 7 days. Inductively coupled plasma atomic emission spectrometry (ICP-AES) was used to analyze the changes in metal elements in the wastewater. Specific results are as follows: Figure 4 As shown.

[0031] Depend on Figure 4It can be seen that among the 32 metals measured, fungi can remove more than 60% of the metal elements. In the carbon source regulation group, the removal rate of Zn, Fe and Zr can be close to 90%, and the removal rate of Cu, Mo and Mg under the action of bacterial-electric coupling can reach 80% to 90%.

[0032] Example 4

[0033] A method for treating high-salinity wastewater using fungi includes the following steps:

[0034] Immobilized fungi were introduced into high-salinity wastewater using cotton thread and treated with a fungus-electrocoupling technique. The experimental period was set to 7 days. The susceptibility of the fungi to UV radiation was measured at 254 nm using a UV spectrophotometer. 254 The removal effect, specific results are as follows Figure 5 As shown.

[0035] Depend on Figure 5 It can be seen that bacterial electrocoupling is relevant to UV radiation in high-salt wastewater. 254 It has a significant removal effect, with a removal rate of 57.60% on the 3rd day. In the later stages, due to the metabolic activity of fungi, some organic matter is regenerated or new organic matter is generated, which reduces the removal rate. However, it can still reach 39.48% on the 7th day, which is higher than the removal rate of electrochemical treatment alone. This shows that fungi can gradually adsorb and degrade humic substances and aromatic compounds containing C=C and C=O double bonds in sewage.

[0036] Example 5

[0037] A method for treating high-salinity wastewater using fungi includes the following steps:

[0038] Immobilized fungi were introduced into high-salinity wastewater and treated using fungus-electrocoupling technology. The experimental period was set to 5 days. 3D-EEM was used to describe the changes in organic matter in the high-salinity wastewater on day 15. Specific results are as follows: Figure 5 As shown.

[0039] Depend on Figure 6 It can be seen that during microbial electrocoupling, significant changes in regions III and V can be observed on the first day. The removal rates of fulvic acid-like substances and humic acid substances reached 92% and 79%, respectively, and the removal rates continued to increase by 3% and 9% after the fifth day. Aromatic protein I had a removal rate of only 13% on the first day, but aromatic protein II reached a removal rate of 50%, and soluble microbial products were also removed by 38%.

[0040] In summary, this invention demonstrates that electrical stimulation can effectively assist fungi in surviving in high-salt environments and slow down their aging rate in high-salt wastewater, thereby improving fungal degradation efficiency, promoting resource recovery, and enhancing treatment stability. This provides an effective treatment method for high-salt wastewater. With the aid of electrical stimulation, fungi effectively remove aromatic protein II, fulvic acid, humic acid, aromatic rings, and soluble microbial products from high-salt wastewater, reducing the burden on subsequent wastewater treatment processes, minimizing the use of chemical agents and treatment time, and thus lowering overall treatment costs. Fungi can effectively inhibit the formation of toxic compounds in high-salt wastewater and have a significant degradation effect on pharmaceutically active compounds, thereby reducing the impact on water bodies and ecosystems and protecting aquatic organisms and ecological balance. During the degradation process, fungi release nutrients such as nitrogen and phosphorus, which can be used for subsequent agricultural fertilization or water treatment, promoting resource recycling.

[0041] The number of devices and processing scale described herein are for the purpose of simplifying the description of the invention, and applications, modifications and variations thereof will be apparent to those skilled in the art.

[0042] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and illustrations shown and described herein.

Claims

1. A method for treating high-salinity wastewater using fungi, characterized in that, include: A microbial-electric coupling device, comprising a container, high-salt wastewater placed in the container, an anode and a cathode placed in the high-salt wastewater, immobilized fungi placed in the high-salt wastewater, and a DC power supply electrically connected to the anode and the cathode; Different voltages are applied to the high-salinity wastewater using the DC power supply; The high-salt wastewater is treated by using fungi through carbon source regulation and electrical stimulation. The fungus is *Cyclophorus vulgaris*.

2. The method for treating high-salinity wastewater using fungi as described in claim 1, characterized in that, The immobilized fungi were prepared as follows: Add the prepared mycelial suspension to the cooled Kirk liquid medium, ensuring uniform dispersion, then add the trimmed cotton thread carrier and mix with the suspension. After completion, place the culture bottle in a constant temperature shaker and incubate for 5-7 days, setting the parameters to 28℃ and 150rpm.

3. The method for treating high-salinity wastewater using fungi as described in claim 1, characterized in that, The bacterial-electric coupling device uses a common three-hole three-electrode electrolytic cell as the liquid reaction vessel, and applies voltage through a DC power supply. The electrode size is 200*250mm and the electrode spacing is 20mm. The anode material is any one or more alloys of zinc, aluminum, iridium, nickel, titanium, and copper. The cathode material is any one or more alloys of platinum, copper, bismuth, and iron, or carbon material.

4. The method for treating high-salinity wastewater using fungi as described in claim 1, characterized in that, The fungus was inoculated in a high-salinity sterile liquid culture medium. Specifically, NaCl was added to increase the conductivity and salinity of the Kirk liquid culture medium. After inoculation, a voltage was applied through a DC power supply, a voltage gradient was set, and the culture was carried out for 7 days.

5. The method for treating high-salinity wastewater using fungi as described in claim 1, characterized in that, Before using the bacteria-electric coupling device, aerate near the cathode of the device for 10 minutes at a gas flow rate of 0.6 L / min, and do not provide aeration afterward.

6. The method for treating high-salinity wastewater using fungi as described in claim 1, characterized in that, The fungal immobilization carrier material used in the experiment was one or a combination of several of the following: polyester fiber, cotton thread, polypropylene fiber, nylon mesh, copper wire, titanium wire, and aluminum wire.

7. The method for treating high-salinity wastewater using fungi as described in claim 1, characterized in that, The fungi were used to biologically treat actual high-salinity wastewater. The dosage of the immobilized fungi in the experiment was 1~10 DCW / L, and the experimental period was 4~10 days. The salinity of the actual high-salinity wastewater ranged from 3-6 g / L, and the initial pH was 6-9.

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