A bacterial agent for treating wastewater containing benzalkonium chloride and its application

Abstract

The invention belongs to the technical field of wastewater treatment, and particularly relates to a bacterial agent for treating benzalkonium chloride-containing wastewater and an application thereof. The bacterial agent is obtained by regulating and controlling experimental environmental parameters and domesticating the bacterial agent, wherein the mass concentration percentage of each bacterial species is 32.37% of Pseudomonas, 21.94% of Rhizobium, 14.69% of Achromobacter, 4.65% of Stenotrophomonas, 3.79% of T. mobilis, 2.41% of Flavobacterium, 2.26% of Alcaligenes, 1.88% of Acetogenic Proteinophilus, 1.59% of Bacillus and 0.53% of Aeromonas. The bacterial agent can improve the degradation rate of COD in the benzalkonium chloride-containing wastewater.

Description

Technical Field

[0001] The invention belongs to the technical field of wastewater treatment, and particularly relates to a bacterial agent for treating benzalkonium chloride-containing wastewater and application thereof. Background Art

[0002] In recent years, people have become more stringent in their requirements for personal hygiene and living environment hygiene. The popularity of medicines and personal care products has made them indispensable daily necessities for people today. For example, human or veterinary medicines include anti-inflammatory drugs, analgesics and antibiotics, as well as disinfectants or fragrances used for personal care. The wastewater discharged by enterprises that produce the above-mentioned daily necessities is often rich in benzalkonium chloride. Benzalkonium chloride is the most common active ingredient in disinfectants. It has a broad spectrum and high efficiency in killing bacteria and algae, and can effectively control the growth of bacteria, algae and slime in water bodies. This type of disinfection wastewater not only contains suspended matter, but also some disinfectant residues that are difficult to biodegrade. This wastewater inevitably harms water bodies and aquatic ecological environments.

[0003] Biological methods for treating benzalkonium chloride-containing wastewater, such as mixed-bed aerated biological filters, offer advantages over physical and chemical methods, such as low cost, simple operation, and no secondary pollution. However, biological methods can suffer from low treatment efficiency and significant susceptibility to environmental factors, resulting in unstable treatment results. The key to addressing these issues lies in maximizing the performance of microorganisms and utilizing their metabolic processes to degrade organic pollutants in wastewater. Studies have shown that while the use of a single bacterial strain can achieve some treatment results, it can still be associated with long reaction times and unstable treatment results.

[0004] Therefore, in order to improve the efficiency of wastewater biological treatment and achieve stable operation, it is crucial to obtain a composite bacterial agent with high efficiency in degrading organic pollutants. Summary of the Invention

[0005] In order to solve the problems of the background technology, the present invention provides a bacterial agent for treating wastewater containing benzalkonium chloride and application thereof.

[0006] The technical solutions of the present invention are as follows:

[0007] The present invention provides a bacterial agent for treating wastewater containing benzalkonium chloride, comprising the following components:

[0008] Pseudomonas, Achromobacter, Rhizobium, Stenotrophomonas, Tistrella mobilis, Flavobacterium, Alcaligenes, Acetogenic Proteophilus, Bacillus and Aeromonas.

[0009] The mass percentage of each component is 32.37%-43.7% for Pseudomonas, 14.69%-44.33% for Achromobacter, 1.2%-28.53% for Rhizobium, 4.65%-7.81% for Stenotrophomonas, 0.02%-3.79% for Tistrella mobilis, 2.21%-2.41% for Flavobacterium, 0.01%-2.26% for Alcaligenes, 0.19%-1.88% for Acetaminophen, 0.22%-1.59% for Bacillus and 0.53%-0.83% for Aeromonas.

[0010] Preferably, the mass percentages of Pseudomonas, Achromobacter, Stenotrophomonas and Aeromonas are 32.37%, 14.69%, 4.65% and 0.53% respectively, and the mass percentages of Rhizobium, Tistrina mobilis, Flavobacterium, Alcaligenes, Acetogenic Proteinophilus and Bacillus are 21.94%, 3.79%, 2.41%, 2.26%, 1.88% and 1.59% respectively.

[0011] The present invention also provides an application of the bacterial agent for treating benzalkonium chloride-containing wastewater, comprising: adding 5 g / L or 10 g / L of the bacterial agent to the benzalkonium chloride-containing wastewater to be treated, performing anaerobically treatment at 28-34° C. for 5 days, and then performing aerobic treatment.

[0012] The method also includes: setting the temperature during the treatment process, using untreated benzalkonium chloride-containing wastewater to replace the treated benzalkonium chloride-containing wastewater mixture or its filtered supernatant, or adding nutrient salts or adsorption carriers during the treatment process.

[0013] During the treatment process, the temperature was set at 32° C., untreated benzalkonium chloride-containing wastewater was used to replace the supernatant of the treated benzalkonium chloride-containing wastewater mixture once a day, and 0.25-0.5 g / L of potassium dihydrogen phosphate was added once every three days.

[0014] During the treatment process, the temperature was set at 34° C., untreated benzalkonium chloride-containing wastewater was used to replace the supernatant of the treated benzalkonium chloride-containing wastewater mixture once a day, and 0.25-0.5 g / L of potassium dihydrogen phosphate was added once every three days.

[0015] During the treatment process, the temperature was set at 34° C., untreated benzalkonium chloride-containing wastewater was used to replace the supernatant of the treated benzalkonium chloride-containing wastewater mixture every three days, and 0.25-0.5 g / L of potassium dihydrogen phosphate was added every three days.

[0016] During the treatment process, the temperature was set at 34°C, and the treated benzalkonium chloride-containing wastewater mixture was replaced with untreated benzalkonium chloride-containing wastewater every three days. 0.5 g / L of potassium dihydrogen phosphate and 5 g / L of activated carbon were added every three days.

[0017] The COD removal rate reached 93.51%.

[0018] Beneficial effects

[0019] The present invention provides a bacterial agent for treating benzalkonium chloride-containing wastewater. By regulating experimental environmental parameters, the degradation efficiency of the substrate is enhanced, and the operation is simple and the pertinence is strong. The prepared composite bacterial agent has high removal efficiency for pollutants and can achieve stable operation of wastewater.

[0020] The main purpose of the bacterial agent provided by the present invention is to treat the COD degradation problem in disinfection wastewater containing benzalkonium chloride, maintain stable water quality, integrate dominant bacterial species in the wastewater, and increase the degradation rate of COD in such wastewater, thereby achieving green discharge of wastewater. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is the COD concentration change diagram of wastewater under different dosages of bacterial agents in Example 1;

[0022] Figure 2 This is the graph showing the changes in COD concentration and removal rate of inlet and outlet water under different parameter conditions of adding bacterial agent in Example 2;

[0023] Figure 3 Schematic diagram of the percentage of bacterial species composition at the genus level in each system under the optimal parameter conditions of Example 3. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0025] A bacterial agent for treating wastewater containing benzalkonium chloride, comprising the following components:

[0026] Pseudomonas (microorganisms of the genus Pseudomonas), Achromobacter (microorganisms of the genus Achromobacter), Rhizobium (microorganisms of the genus Rhizobiaceae), Stenotrophomonas (microorganisms of the genus Stenotrophomonas), Tistrella mobilis (microorganisms of the genus Tistrella), Flavobacterium (microorganisms of the genus Flavobacterium), Alcaligens (microorganisms of the genus Alcaligenaceae), Proteiniphilum (microorganisms of the genus Proteininiphilum), Bacillus (microorganisms of the genus Bacillus) and Aerococcus (microorganisms of the genus Aerococcus).

[0027] The mass percentage of each component is 32.37%-43.7% for Pseudomonas, 14.69%-44.33% for Achromobacter, 1.2%-28.53% for Rhizobium, 4.65%-7.81% for Stenotrophomonas, 0.02%-3.79% for Tistrella mobilis, 2.21%-2.41% for Flavobacterium, 0.01%-2.26% for Alcaligenes, 0.19%-1.88% for Acetaminophen, 0.22%-1.59% for Bacillus and 0.53%-0.83% for Aeromonas.

[0028] Preferably, the mass percentages of Pseudomonas, Achromobacter, Stenotrophomonas, and Aeromonas are 32.37%, 14.69%, 4.65%, and 0.53%, respectively; and the mass percentages of Rhizobium, T. mobilis, Flavobacterium, Alcaligenes, acetogenic proteinophilus, and Bacillus are 21.94%, 3.79%, 2.41%, 2.26%, 1.88%, and 1.59%, respectively. The bacterial agent is used to treat wastewater containing benzalkonium chloride and has the highest COD removal rate, reaching 93.51%.

[0029] The present invention also provides an application of the bacterial agent for treating benzalkonium chloride-containing wastewater, comprising: adding 5 g / L or 10 g / L of the bacterial agent to the benzalkonium chloride-containing wastewater to be treated, performing anaerobically treatment at 28-34° C. for 5 days, and then performing aerobic treatment.

[0030] The method also includes: setting the temperature during the treatment process, using untreated benzalkonium chloride-containing wastewater to replace the treated benzalkonium chloride-containing wastewater mixture or its filtered supernatant, or adding nutrient salts or adsorption carriers during the treatment process.

[0031] During the treatment process, the temperature was set at 32° C., untreated benzalkonium chloride-containing wastewater was used to replace the supernatant of the treated benzalkonium chloride-containing wastewater mixture once a day, and 0.25-0.5 g / L of potassium dihydrogen phosphate was added once every three days.

[0032] During the treatment process, the temperature was set at 34° C., untreated benzalkonium chloride-containing wastewater was used to replace the supernatant of the treated benzalkonium chloride-containing wastewater mixture once a day, and 0.25-0.5 g / L of potassium dihydrogen phosphate was added once every three days.

[0033] During the treatment process, the temperature was set at 34° C., untreated benzalkonium chloride-containing wastewater was used to replace the supernatant of the treated benzalkonium chloride-containing wastewater mixture every three days, and 0.25-0.5 g / L of potassium dihydrogen phosphate was added every three days.

[0034] During the treatment process, the temperature was set at 34°C, and the treated benzalkonium chloride-containing wastewater mixture was replaced with untreated benzalkonium chloride-containing wastewater every three days. 0.5 g / L of potassium dihydrogen phosphate and 5 g / L of activated carbon were added every three days.

[0035] The present invention enhances the degradation efficiency of the substrate by regulating experimental environmental parameters, has simple operation and strong pertinence, and the prepared bacterial agent has high removal efficiency of pollutants in benzalkonium chloride wastewater and can achieve stable operation of water quality.

[0036] The main purpose of the bacterial agent of the present invention is to treat the COD degradation problem in disinfection wastewater containing benzalkonium chloride, maintain stable water quality, integrate dominant bacterial species, and increase the degradation rate of COD in such wastewater, thereby realizing green discharge of wastewater.

[0037] Example 1

[0038] The wastewater in this example was taken from a daily necessities company in Suzhou, containing benzalkonium chloride disinfection wastewater, with a COD concentration of 2964 mg / L. Two parallel control groups, D1 and D2, and D3 and D4, were set up. 200 mL of wastewater was taken from each control group. The dosage of the bacterial agent in D1 and D2 was 5 g / L, and the dosage of the bacterial agent in D3 and D4 was 10 g / L. From June 28 to July 12, 2024, the system did not change the water during this period, the temperature was set at 32°C, and 0.1 g of potassium dihydrogen phosphate was added every three days. The effect of different dosages of bacterial agents on the COD degradation effect in the wastewater was investigated.

[0039] The experimental results showed that COD concentrations dropped rapidly after the system began anaerobic operation under film covering for five days starting on June 28. On July 3, COD concentrations in D1, D2, D3, and D4 dropped to 2498 mg / L, 2574 mg / L, 2242 mg / L, and 1881 mg / L, respectively. The degradation rates of D3 and D4 were significantly greater than those of D1 and D2. After switching to aerobic operation on July 5, COD continued to be degraded. On July 6, COD concentrations in D1 and D2 dropped to 2358 mg / L and 2016 mg / L, respectively, while those in D3 and D4 dropped to 1790 mg / L and 1246 mg / L, respectively. After a week of aerobic operation without water changes, the COD content of the benzalkonium chloride-containing wastewater continued to decline, ultimately stabilizing at 1520 mg / L, 1760 mg / L, 812.7 mg / L, and 857.8 mg / L for D1, D2, D3, and D4, respectively. COD removal efficiencies for D1, D2, D3, and D4 reached 48.72%, 40.62%, 72.58%, and 71.06%, respectively.

[0040] The comparison shows that the COD removal efficiency of the benzalkonium chloride-containing wastewater with a bacterial agent dosage of 10 g / L is better than that with a bacterial agent dosage of 5 g / L.

[0041] Example 2

[0042] The wastewater in this example was also taken from the benzalkonium chloride disinfection wastewater of a daily necessities company in Suzhou, with a COD concentration of 2964 mg / L. The original wastewater concentration L0 was set, and two parallel control groups L1, L2 and L3, L4 were used. 200 mL of wastewater was taken from each control group, of which L1 and L2 were the treatment conditions of D1 and D2 in which Example 1 was running stably, and L3 and L4 were the treatment conditions of D3 and D4 in which Example 1 was running stably. The COD removal rates of L1, L2, L3, and L4 were Q1, Q2, Q3, and Q4, respectively. From July 12 to November 6, the degradation capacity of COD in the wastewater was further improved by changing parameters including temperature, water change frequency, water change type, nutrient salt and adsorption carrier addition.

[0043] Among them, the temperature is 32℃ or 34℃, the water change frequency is once a day or once every three days, the water change type is supernatant (200mL of the filtered supernatant is replaced by the original wastewater) or mud-water mixture (200mL of the unfiltered mixture is replaced by the original wastewater), and the nutrient salt and adsorption carrier are potassium dihydrogen phosphate and activated carbon respectively.

[0044] Since July 12, the water change frequency of L1, L2, L3, and L4 has been every day / time, and the water change type is all supernatant. 0.1g of potassium dihydrogen phosphate is added every three days / time, and no adsorption carrier is added. When the temperature rises from 32°C to 34°C (July 26), the degradation rate of COD increases significantly. The COD concentrations of L1 and L2 dropped from 1896mg / L and 1711mg / L to 1384mg / L and 1038mg / L, respectively. Q1 and Q2 increased by 17.28% and 22.71%, respectively. The COD concentrations of L3 and L4 showed a continuous downward trend after the temperature was raised. As the temperature rises, the cell metabolism of microorganisms is accelerated, which promotes the growth of microorganisms, is beneficial to the COD degradation of the wastewater, and improves the COD removal efficiency.

[0045] When the temperature was 34°C, the water change type for L1, L2, L3, and L4 was all supernatant, and 0.1g potassium dihydrogen phosphate was added every three days. Without adding an adsorption carrier, the water change frequency was changed from July 26 to August 27 during operation. L1 and L3 were changed every day, and L2 and L4 were changed every three days. During this test phase, the COD concentrations of L1, L2, L3, and L4 fluctuated, and the degradation rate slowed down. The COD concentrations eventually reached 1023mg / L, 797.6mg / L, 993.3mg / L, and 737.4mg / L, respectively. The COD removal rates of Q1, Q2, Q3, and Q4 were 65.49%, 73.09%, 66.49%, and 75.12%, respectively. The COD removal rates of L2 and L4 were significantly higher than those of L1 and L3. It can be seen that extending the frequency of water changes and increasing the reaction time have a certain effect on the COD degradation by microorganisms using organic matter in wastewater.

[0046] Based on the results of the previous tests, during the operation period from August 27 to September 29, the temperature was maintained at 34°C, and the water change frequency of L1, L2, L3, and L4 was changed to every three days, and 0.1g of potassium dihydrogen phosphate was added every three days. The type of water change was changed, and L1 and L3 were replaced with a sludge-water mixture, while L2 and L4 were replaced with a supernatant. At the same time, on August 31, 1g of activated carbon was added to L1 and L4, while L2 and L3 were not added. With the addition of the carrier, the sludge flocs were gradually adsorbed by the activated carbon, and the microbial biomass increased. On August 31, the COD concentrations of L1 and L4 dropped significantly, from 1023mg / L and 737.4mg / L to 707.3mg / L and 526.7mg / L, respectively. As the test continued, the COD concentrations of L1 and L4 eventually dropped to 310.8 mg / L and 391.8 mg / L, respectively. Q1 and Q4 were as high as 89.51% and 86.78%, respectively. After achieving quantitative sludge discharge, the COD concentration in the wastewater was continuously degraded, with the COD concentration of L2 dropping to 594.5 mg / L and the COD concentration of L3 dropping to 418.9 mg / L. Q2 and Q3 were as high as 79.94% and 85.87%, respectively. Compared with L2, the COD degradation effect of L3 was slightly better. The operation results proved that under the dual effects of adding adsorption carriers and sludge discharge, the COD degradation efficiency of the wastewater was higher.

[0047] From October 8th to November 6th, L1, L2, L3, and L4 were operated under the aforementioned optimal parameters: a temperature of 34°C, water changes every three days, a mud-water mixture, 0.5g / L of potassium dihydrogen phosphate supplemented every three days, and 5g / L of activated carbon added. During this period, L0 increased to 5500mg / L. Even under high organic matter concentrations, the system of this embodiment maintained stable operation, maintaining high COD removal rates. Q1, Q2, Q3, and Q4 reached 92%, 91.94%, 91.65%, and 93.51%, respectively.

[0048] The above test results show that the system L4 with the addition of 10g / L bacterial agent and the optimal parameter conditions has the best removal effect on COD in wastewater containing benzalkonium chloride.

[0049] Example 3

[0050] Depend on Figure 3 It can be seen that the bacterial species composition analysis of each system L1, L2, L3, and L4 under the optimal parameter conditions corresponds to Figure 3 Among T1, T2, T3, and T4, it was found that the components of the bacterial agents with high COD degradation ability include Pseudomonas (microorganisms of the genus Pseudomonas), Achromobacter (microorganisms of the genus Achromobacter), Rhizobium (microorganisms of the genus Rhizobiaceae), Stenotrophomonas (microorganisms of the genus Stenotrophomonas), Tistrella (microorganisms of the genus Tistrella), Flavobacterium (microorganisms of the genus Flavobacterium), Alcaligenaceae (microorganisms of the genus Alcaligenaceae), Proteiniphilum (microorganisms of the genus Proteininiphilum), Bacillus (microorganisms of the genus Bacillus) and Aerococcus (microorganisms of the genus Aerococcus).

[0051] Measured on a pure bacteria basis, the mass percentage of bacterial cells in each component is 32.37%-43.7% for Pseudomonas, 14.69%-44.33% for Achromobacter, 1.2%-28.53% for Rhizobium, 4.65%-7.81% for Stenotrophomonas, 0.02%-3.79% for Tistrella mobilis, 2.21%-2.41% for Flavobacterium, 0.01%-2.26% for Alcaligenes, 0.19%-1.88% for Acetaminophen, 0.22%-1.59% for Bacillus and 0.53%-0.83% for Aeromonas.

[0052] Under the optimal parameters (10 g / L of inoculant, 34°C temperature, water exchange every three days, mud-water mixture, 0.5 g / L potassium dihydrogen phosphate supplementation every three days, and 5 g / L activated carbon), the T4 system had the lowest mass percentages of Achromobacter, Pseudomonas, Stenotrophomonas, and Aeromonas compared to the T1, T2, and T3 systems, at 14.69%, 32.37%, 4.65%, and 0.53%, respectively. The T4 system also had the highest mass percentages of Rhizobium, T. mosulina, Flavobacterium, Alcaligenes, Proteophilus acetogenes, and Bacillus, reaching 21.94%, 3.79%, 2.41%, 2.26%, 1.88%, and 1.59%, respectively. The synergistic effect of the microorganisms promoted the efficient degradation of high COD concentrations in benzalkonium chloride-containing wastewater, ensuring stable system operation.

Claims

1. An application of a bacterial agent for treating wastewater containing benzalkonium chloride, characterized in that: include: 5 g / L or 10 g / L of bacterial agent was added to the wastewater containing benzalkonium chloride to be treated, and after anaerobic treatment at 28-34°C for 5 days, aerobic treatment was performed; the COD concentration of the wastewater was 2964 mg / L; The mass percentage of each component of the microbial agent is 32.37%-43.7% for Pseudomonas, 14.69%-44.33% for Achromobacter, 1.2%-28.53% for Rhizobium, 4.65%-7.81% for Stenotrophomonas, 0.02%-3.79% for T. motilium, 2.21%-2.41% for Flavobacterium, 0.01%-2.26% for Alcaligenes, 0.19%-1.88% for Acetogenic Proteinophilus, 0.22%-1.59% for Bacillus and 0.53%-0.83% for Aeromonas.

2. The application of the bacterial agent for treating benzalkonium chloride-containing wastewater according to claim 1, wherein The mass percentages of Pseudomonas, Achromobacter, Stenotrophomonas and Aeromonas were 32.37%, 14.69%, 4.65% and 0.53%, respectively; the mass percentages of Rhizobium, Tistrella motilium, Flavobacterium, Alcaligenes, Acetogenic Proteophilus and Bacillus were 21.94%, 3.79%, 2.41%, 2.26%, 1.88% and 1.59%, respectively.

3. The application of the bacterial agent for treating benzalkonium chloride-containing wastewater according to claim 1, wherein Also includes: The temperature is set during the treatment process, untreated benzalkonium chloride-containing wastewater is used to replace the treated benzalkonium chloride-containing wastewater mixture or its filtered supernatant, or nutrient salts or adsorption carriers are added during the treatment process.

4. The application of the bacterial agent for treating benzalkonium chloride-containing wastewater according to claim 3, wherein During the treatment process, the temperature was set at 32°C, and the supernatant of the treated benzalkonium chloride wastewater mixture was replaced with untreated benzalkonium chloride wastewater once a day. Potassium dihydrogen phosphate was added at a concentration of 0.25-0.5 g / L every three days.

5. The application of the bacterial agent for treating benzalkonium chloride-containing wastewater according to claim 3, wherein During the treatment process, the temperature was set at 34°C, and the supernatant of the treated benzalkonium chloride wastewater mixture was replaced with untreated benzalkonium chloride wastewater once a day. Potassium dihydrogen phosphate was added at a concentration of 0.25-0.5 g / L every three days.

6. The application of the bacterial agent for treating wastewater containing benzalkonium chloride according to claim 3, wherein During the treatment process, the temperature was set at 34°C, and the supernatant of the treated benzalkonium chloride wastewater mixture was replaced with untreated benzalkonium chloride wastewater every three days, and 0.25-0.5 g / L potassium dihydrogen phosphate was added every three days.

7. The use of a bacterial agent for treating wastewater containing benzalkonium chloride according to claim 3, wherein During the treatment process, the temperature was set at 34°C, and the treated benzalkonium chloride-containing wastewater mixture was replaced with untreated benzalkonium chloride-containing wastewater every three days. 0.5 g / L of potassium dihydrogen phosphate and 5 g / L of activated carbon were added every three days.

8. The use of a bacterial agent for treating wastewater containing benzalkonium chloride according to claim 7, wherein The COD removal rate reached 93.51%.

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