Method for removing smelly substances by catalyzing potassium ferrate through micro-nano bubbles

Abstract

The invention relates to a method for removing smelly substances by catalyzing potassium ferrate through micro-nano bubbles, and aims to solve the problems that the smelly substances of a water source in current water treatment exceed the standard, and GSM and MIB are difficult to treat. The method for removing the smelly substances comprises the following steps: 1, introducing a water body containing the smelly substances into the water tank, arranging a nano ceramic membrane assembly in the water tank, blowing air into the nano ceramic membrane assembly through the air pump, and generating micro-nano bubbles in the water body; and 2, treating the water body containing the odor substances through the micro-nano bubbles, and then adding potassium ferrate into the water body containing the odor substances for oxidation treatment, thereby completing the method for removing the odor substances by catalyzing the potassium ferrate through the micro-nano bubbles. According to the method, diffusion of the potassium ferrate in the aqueous solution is accelerated through the micro-nano bubbles, the contact area of the potassium ferrate and target pollutants is increased, the efficiency of catalyzing the potassium ferrate to degrade GSM and MIB through the micro-nano bubbles is high, the process is simple, and wide application prospects are achieved.

Description

Technical Field

[0001] The present invention belongs to the field of removing odor substances from drinking water, and particularly relates to a method for removing odor substances from water by using micro-nano bubbles to catalyze potassium ferrate. Background Art

[0002] When water eutrophication breaks out and algal blooms occur, odor substances will be produced. The main odor components from most algae and cyanobacteria are usually terpenoids, carotenoid derivatives, fatty acid derivatives, and sulfur compounds. Among the odors released by numerous algae and cyanobacteria, geosmin (GSM) and 2-methylisoborneol (2-MIB) with earthy / musty odors have been widely studied. It is known that GSM and 2-MIB are produced by various cyanobacteria, such as Oscillatoria, Lyngbya, and Anabaena. GSM and 2-MIB are the main compounds causing bad tastes and odors in water. These compounds are volatile in nature, causing musty and earthy smells, and their presence in drinking water will cause more harm. Removing these odor substances (T&O) from drinking water is challenging because their odor threshold concentrations are usually in nanograms per liter (the discharge standards for GSM & 2-MIB stipulated in GB5749-2022 are 10 ng / L).

[0003] Potassium ferrate is a new type of non-chlorine green disinfectant with high efficiency and multiple functions. Its redox potentials under acidic and alkaline conditions are 2.20 V and 0.72 V respectively, and its redox ability is relatively strong. It is mainly used for drinking water treatment for sterilization and disinfection, and its oxidized products are non-toxic and harmless. Therefore, using potassium ferrate as a pre-oxidant for algae removal has broad application prospects.

[0004] The micro-nano bubble method, as an efficient and simple water treatment method, has been widely used in the field of water treatment. Micro-nano bubbles are composed of gas and water, avoiding the direct introduction of potential secondary pollutants. It is worth noting that micro-nano bubbles show significant advantages in assisting AOP (advanced oxidation treatment) through interfacial reactions. Summary of the Invention

[0005] The purpose of the present invention is to solve the problem of excessive odor substances in the water source and the difficulty in treating GSM and MIB in current water treatment, and thus provides a method for removing odor substances from water by using micro-nano bubbles to catalyze potassium ferrate.

[0006] The method for using micro-nano bubbles to catalyze potassium ferrate to remove odor substances in the present invention is realized according to the following steps:

[0007] I. Water containing odor substances is introduced into a water tank. A nano-ceramic membrane module is arranged in the water tank, and air is pumped through an air pump into the nano-ceramic membrane module to generate micro-nano bubbles in the water body;

[0008] II. A method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate is provided. The method includes treating the water body containing odor substances with micro-nano bubbles and adding potassium ferrate to the water body containing odor substances for oxidation treatment, so as to complete the method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate.

[0009] In the method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate according to the present invention, the micro-nano bubbles accelerate the diffusion of potassium ferrate in the aqueous solution, increasing the contact area between potassium ferrate and the target pollutants. At the same time, since potassium ferrate can undergo self-decomposition in the aqueous solution, the intermediate-valence iron generated by the self-decomposition has strong oxidation ability. By accelerating the diffusion rate and contact area of potassium ferrate, the oxidation and removal effect of the intermediate-valence iron generated by the self-decomposition of potassium ferrate on the target pollutants is greatly improved.

[0010] The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate according to the present invention has the following beneficial effects:

[0011] 1. Potassium ferrate adopted in the present invention is a green and environmentally friendly oxidant, and will not introduce other harmful and toxic factors into the water body;

[0012] 2. The micro-nano bubble method of the present invention, as an efficient and simple water treatment method, is composed of gas and water, avoiding the direct introduction of potential secondary pollutants;

[0013] 3. The method for using micro-nano bubbles to catalyze potassium ferrate to degrade GSM and MIB in the present invention has high efficiency and simple process, and has broad application prospects. Description of the Drawings

[0014] Figure 1 It is the standard curve of MIB in the embodiment;

[0015] Figure 2 It is the standard curve of GSM in the embodiment;

[0016] Figure 3 It is the structural schematic diagram of the nano-bubble generating device of the present invention. Detailed Embodiments

[0017] Detailed Embodiment 1: The method for using micro-nano bubbles to catalyze potassium ferrate to remove odor substances in this embodiment is realized according to the following steps:

[0018] I. The water body containing odor substances is introduced into a water tank. A nano-ceramic membrane module is arranged in the water tank, and air is pumped into the nano-ceramic membrane module through an air pump to generate micro-nano bubbles in the water body;

[0019] II. The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate is achieved by treating the water body containing odor substances with micro-nano bubbles and adding potassium ferrate to the water body containing odor substances for oxidation treatment at the same time.

[0020] This embodiment combines micro-nano bubbles with potassium ferrate to remove GSM and MIB, with high efficiency, simple process, and broad application prospects.

[0021] Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that the water body containing odor substances contains one or both of geosmin (GSM) and 2-methylisoborneol (2-MIB).

[0022] Specific Embodiment 3: The difference between this embodiment and Specific Embodiment 2 is that the concentration of geosmin in the water body is 10 - 200 ng / L, and the concentration of 2-methylisoborneol is 10 - 200 ng / L.

[0023] Specific Embodiment 4: The difference between this embodiment and any one of Specific Embodiments 1 to 3 is that the nano-ceramic membrane in Step 1 is a hollow fiber ceramic membrane.

[0024] Specific Embodiment 5: The difference between this embodiment and any one of Specific Embodiments 1 to 4 is that the pore diameter of the nano-membrane pores on the nano-ceramic membrane is 10 nm - 100 nm.

[0025] Specific Embodiment 6: The difference between this embodiment and any one of Specific Embodiments 1 to 5 is that in Step 1, air or oxygen is bubbled through an air pump.

[0026] Specific Embodiment 7: The difference between this embodiment and any one of Specific Embodiments 1 to 6 is that in Step 2, the water body containing odor substances is treated with micro-nano bubbles for 20 - 40 min.

[0027] Specific Embodiment 8: The difference between this embodiment and Specific Embodiment 7 is that in Step 2, the water body containing odor substances is treated with micro-nano bubbles for 30 min.

[0028] Specific Embodiment 9: The difference between this embodiment and any one of Specific Embodiments 1 to 8 is that in Step 2, the dosage of potassium ferrate is 0.5 - 2.5 mg / L.

[0029] Specific Embodiment 10: The difference between this embodiment and any one of Specific Embodiments 1 to 9 is that in Step 2, potassium ferrate is added to the water body containing odor substances for oxidation treatment for 10 - 30 min.

[0030] Example 1: The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate in this example is realized according to the following steps:

[0031] 1. Water containing odorant substances is introduced into a pool, where a nano-ceramic membrane module is installed. The nano-ceramic membrane is a hollow fiber ceramic membrane. Air is pumped (by an air pump) into the nano-ceramic membrane module to generate micro-nano bubbles in the water body.

[0032] 2. The water body containing odorant substances is treated with micro-nano bubbles for 30 minutes. While the bubbles are being treated, potassium ferrate is added to the water body containing odorant substances for oxidation treatment for 10 minutes. The dosage of potassium ferrate is 0.5 mg / L, thus completing the method of using micro-nano bubbles to catalyze potassium ferrate to remove odorant substances.

[0033] In this example, the concentrations of GSM and MIB in the raw water containing odorant substances are 100 ng / L respectively.

[0034] The water treatment device in this example is as Figure 3 shown. Air is pumped by an air pump to generate micro-nano bubbles in the water body through the nano-ceramic membrane. The water body containing micro-nano bubbles is then pumped into the nano-ceramic membrane module by a circulation pump.

[0035] In this example, the GC-MS method is used to detect GSM and MIB in water. The specific detection process is as follows:

[0036] In this example, an electron impact ionization source (EI) is used, helium is used as the carrier gas, and the target substances are separated by a medium-polarity chromatographic column DB-1701. The specific method setting parameters are shown in Table 1.

[0037] Table 1 Instrument condition settings for the determination of GSM and 2-MIB

[0038]

[0039]

[0040]

[0041] Applying the GC-MS method to the determination of GSM and 2-MIB, good resolution is achieved in a relatively short time. The retention times, precursor ions, and product ions of GSM and 2-MIB in the MRM mode are shown in Table 2 respectively. The standard curves of MIB and GSM are as Figure 1 and Figure 2 shown respectively.

[0042] Table 2 Retention times and characteristic ions of GSM and 2-MIB

[0043]

[0044] In this example, the removal rate of GSM in the raw water is 52.4%, and the removal rate of MIB is 43.8%.

[0045] Example 2: The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate is realized according to the following steps:

[0046] 1. The water body containing odor substances is introduced into a water tank. A nano-ceramic membrane module is arranged in the water tank. The nano-ceramic membrane is a hollow fiber ceramic membrane. Air is pumped into the nano-ceramic membrane module through an air pump to generate micro-nano bubbles in the water body;

[0047] 2. The water body containing odor substances is treated with micro-nano bubbles for 30 min. While the bubbles are being treated, potassium ferrate is added to the water body containing odor substances for oxidation treatment for 10 min. The dosage of potassium ferrate is 1.5 mg / L, thus completing the method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate.

[0048] In the raw water containing odor substances in this example, the concentrations of GSM and MIB are 100 ng / L respectively.

[0049] In this example, the removal rate of GSM in the raw water is 89.2%, and the removal rate of MIB is 85.4%.

[0050] Example 3: The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate is realized according to the following steps:

[0051] 1. The water body containing odor substances is introduced into a water tank. A nano-ceramic membrane module is arranged in the water tank. The nano-ceramic membrane is a hollow fiber ceramic membrane. Air is pumped into the nano-ceramic membrane module through an air pump to generate micro-nano bubbles in the water body;

[0052] 2. The water body containing odor substances is treated with micro-nano bubbles for 30 min. While the bubbles are being treated, potassium ferrate is added to the water body containing odor substances for oxidation treatment for 10 min. The dosage of potassium ferrate is 2 mg / L, thus completing the method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate.

[0053] In the raw water containing odor substances in this example, the concentrations of GSM and MIB are 100 ng / L respectively.

[0054] In this example, the removal rate of GSM in the raw water is 94.6%, and the removal rate of MIB is 92.6%.

[0055] Example 4: The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate is realized according to the following steps:

[0056] 1. Water containing odorant substances is introduced into a water tank. A nano-ceramic membrane module is installed in the water tank. The nano-ceramic membrane is a hollow fiber ceramic membrane. Air is pumped into the nano-ceramic membrane module by an air pump to generate micro-nano bubbles in the water body.

[0057] 2. The water body containing odorant substances is treated with micro-nano bubbles for 30 minutes. While the bubbles are being treated, potassium ferrate is added to the water body containing odorant substances for oxidation treatment for 10 minutes. The dosage of potassium ferrate is 2.5 mg / L, thus completing the method for removing odorant substances by using micro-nano bubbles to catalyze potassium ferrate.

[0058] In the raw water containing odorant substances in this example, the concentrations of GSM and MIB are 100 ng / L respectively.

[0059] In this example, the removal rate of GSM in the raw water is 95.2%, and the removal rate of MIB is 93.6%.

[0060] Comparative example: The method for removing odorant substances by using potassium ferrate in this example is achieved according to the following steps:

[0061] 1. Water containing odorant substances is introduced into a water tank.

[0062] 2. Potassium ferrate is directly added to the water body containing odorant substances for oxidation treatment for 10 minutes. The dosage of potassium ferrate is 2.5 mg / L, thus completing the method for removing odorant substances by using potassium ferrate alone.

[0063] In the raw water containing odorant substances in this example, the concentrations of GSM and MIB are 100 ng / L respectively.

[0064] In this example, the removal rate of GSM in the raw water is 12.5%, and the removal rate of MIB is 8.7%.

Claims

1. A method for removing odorous substances by catalyzing potassium ferrate with micro-nano bubbles, characterized in that The method of removing odor substances by using micro-nano bubbles to catalyze potassium ferrate is achieved by the following steps:

1. The water containing odorous substances is passed into a pool, in which a nano-ceramic membrane module is arranged, and air is pumped into the nano-ceramic membrane module to generate micro-nano bubbles in the water; Second, the water body containing the odorous substances is treated by micro-nano bubbles, and potassium ferrate is added to the water body containing the odorous substances for oxidation treatment, thereby completing the method of removing the odorous substances by using micro-nano bubbles to catalyze potassium ferrate.

2. The method for removing odorous substances by catalyzing potassium ferrate with micro-nano bubbles according to claim 1, characterized in that Water bodies containing odorous substances contain one or both of geosmin and 2-methylisopentene.

3. The method for removing odorous substances by using micro-nano bubbles to catalyze potassium ferrate according to claim 2, characterized in that The concentration of geosmin in water bodies is 10 to 200 ng / L, and the concentration of 2-methylisopentene is 10 to 200 ng / L.

4. The method for removing odorous substances by using micro-nano bubbles to catalyze potassium ferrate according to claim 1, characterized in that The nano ceramic membrane in step one is a hollow fiber ceramic membrane.

5. The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate according to claim 1, characterized in that The pore size of the nano-membrane pores on the nano-ceramic membrane is 10nm to 100nm.

6. The method for removing odorous substances by catalyzing potassium ferrate with micro-nano bubbles according to claim 1, characterized in that In step one, air or oxygen is blown through an air pump.

7. The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate according to claim 1, characterized in that In step 2, the water containing odorous substances is treated with micro-nano bubbles for 20 to 40 minutes.

8. The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate according to claim 7, characterized in that In step 2, the water containing odorous substances is treated with micro-nano bubbles for 30 minutes.

9. The method for removing odorous substances by using micro-nano bubbles to catalyze potassium ferrate according to claim 1, characterized in that In step 2, the dosage of potassium ferrate is 0.5-2.5 mg / L.

10. The method for removing odor substances by using micro-nano bubbles to catalyze potassium ferrate according to claim 1, characterized in that In step 2, potassium ferrate is added to the water body containing the odorous substances for oxidation treatment for 10 to 30 minutes.

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