Method for enhancing the ability of anaerobic biological treatment of high-chlorine wastewater by using betaine combined with modified bentonite

Abstract

The present application belongs to the technical field of environmental protection, and particularly relates to a method for enhancing the ability of anaerobic biological treatment of high-chlorine wastewater by using betaine and modified bentonite in combination. The method mainly improves the activity of anaerobic bacteria groups in a high-chlorine environment by simultaneously adding betaine and modified bentonite, so as to effectively enhance the ability of anaerobic bacteria groups to degrade pollutants and the ability to adsorb and intercept chlorine ions in high-chlorine wastewater. The present application is the first to solve the technical problem of high-chlorine wastewater treatment by simultaneously adding betaine and modified bentonite to an anaerobic biological treatment system. Betaine can accumulate in the cell interior to alleviate osmotic pressure; at the same time, modified bentonite can adsorb chlorine ions, and the combined action of the two can complement each other to improve the removal effect of COD (chemical oxygen demand), and in addition, can promote the secretion of EPS (extracellular polymeric substance) by anaerobic microorganisms to increase the adsorption of chlorine ions.

Description

Technical Field

[0001] This invention belongs to the field of environmental protection technology, specifically relating to a method for enhancing the anaerobic biological treatment capacity of high-chlorine wastewater by using betaine in combination with modified bentonite. Background Technology

[0002] In recent years, the amount of water recycled within enterprises has increased, leading to a continuous increase in the concentration of chloride ions in wastewater.

[0003] Currently, the main methods for treating high-chlorine wastewater include physical evaporation, membrane separation, electrochemical dialysis, and biological treatment. However, physical and chemical methods are less effective at removing soluble organic matter, often requiring the construction of entirely new treatment facilities and the training of professional personnel, significantly extending treatment time and increasing costs. Furthermore, equipment replacement and maintenance necessitate downtime. Biological methods are widely used in most wastewater treatment plants in my country due to their environmental friendliness and economic efficiency, and have a well-established equipment base. However, high chloride ion concentrations can cause osmotic pressure imbalances, leading to poor biological activity and consequently, ineffective treatment. Therefore, finding a cost-effective and efficient wastewater treatment technology that can remove organic pollutants and adsorb chloride ions from high-chlorine wastewater is of significant research importance.

[0004] Betaine is a common compatible solute with the molecular formula C5H10. 11 NO2. The accumulation of compatible solutes, such as betaine, within cells can balance the osmotic pressure inside and outside the cell, increase intracellular water activity, and bring cell volume and osmotic pressure to normal levels without hindering normal cellular metabolic activities. Furthermore, betaine is widely found in nature, has no biological toxicity, and industrial betaine is relatively inexpensive.

[0005] Bentonite is a natural rock composed of montmorillonite minerals, with a specific surface area generally ranging from 20 to 60 m². 2 The montmorillonite contains a layered hydrated aluminosilicate structure, with cations such as K, Cu, Mg, and Na within its interlayers. These cations and the crystal structure within montmorillonite are unstable, leading to ion exchange reactions. Bentonite also possesses chemical and mechanical stability, high adsorption capacity, and unique structural characteristics. Furthermore, bentonite can be modified in various ways; alkali modification enhances its chloride ion adsorption capacity, while calcination modification alters its internal structure, further increasing adsorption capacity. Using modified bentonite as a raw material, it offers effective and cost-efficient adsorption of chloride ions from high-chlorine wastewater.

[0006] Chinese invention patent application CN111717982A, entitled "Method for Enhancing Biochemical Treatment of High-Salinity Organic Wastewater by Detoxifying Microorganisms with High-Salinity Toxicity," discloses a method that utilizes compatible solutes such as glycine betaine, glycerol, sugar alcohols, and amino acids as osmotic protectants to improve the effectiveness of aerobic sludge treatment of high-salt organic wastewater. It also employs pressurization of the reactor to enhance biological activity, achieving improved treatment efficiency through the coupling of pressurization and the addition of compatible solutes. While this patent does indeed achieve the goal of improving biological treatment of high-salt wastewater, it still has shortcomings: First, the patent only covers aerobic biological treatment methods, but anaerobic biological treatment is also an important component of my country's wastewater treatment industry, and anaerobic treatment methods are often more effective for difficult-to-treat high-salt and high-chlorine wastewater. Second, while the patent mentions pressurizing the reactor to improve treatment efficiency, the technical and equipment requirements for pressurization are difficult for most wastewater treatment devices to meet. Finally, the patent does not consider using adsorption to directly remove chloride ions and other inorganic ions from high-salt and high-chlorine wastewater. Summary of the Invention

[0007] This invention comprehensively considers the problems of poor removal efficiency of organic pollutants and chloride ions in existing technologies for industrial high-chlorine wastewater, and proposes a method to enhance the anaerobic biological treatment capacity of high-chlorine wastewater by using betaine in combination with modified bentonite. This method is applicable to anaerobic biological treatment, which has a wide range of applications. It takes into account both the enhanced activity of anaerobic microorganisms in high-chlorine environments and the adsorption of chloride ions in high-chlorine wastewater. At the same time, it does not have strict requirements on the type of reactor and has a wide range of applications.

[0008] This invention is the first to solve the technical challenge of treating high-chlorine wastewater by simultaneously adding betaine and modified bentonite to an anaerobic biological treatment system.

[0009] To address the problems of low microbial activity, mass microbial death during water quality fluctuations, long treatment cycles, and low efficiency in the current biological treatment of high-chlorine wastewater, the primary objective of this invention is to provide a method for anaerobic biological treatment of high-chlorine wastewater using betaine combined with modified bentonite as an exogenous additive. In the initial stages of this invention, parallel experiments were conducted on various compatible solutes with similar effects (betaine, trehalose, glutamic acid, glycine, and tetrahydropyrimidine) to comprehensively evaluate the treatment effects. Ultimately, betaine was selected as the optimal agent based on a comprehensive assessment of treatment effect and cost. In addition, parallel experiments were conducted on various commonly used adsorbents (bentonite, diatomaceous earth, and kaolin), including alkali modification and calcination modification experiments under different conditions. The treatment effects were comprehensively evaluated, and modified bentonite with a specific modification method was ultimately selected. Betaine and modified bentonite are in granular and powder form, respectively, making them easy to add, inexpensive, and significantly improving the salt tolerance of anaerobic microorganisms without causing secondary pollution.

[0010] A second objective of this invention is to provide a specific modification method for the aforementioned modified bentonite.

[0011] The bentonite modification method in this invention is as follows: First, the bentonite raw material is soaked in 0.5 mol / L to 2 mol / L NaOH for 1 to 3 hours. Then, the bentonite is filtered out, naturally dried, and continuously calcined at 500℃ to 650℃ for 2 to 4 hours to obtain alkali-modified and calcined bentonite. Modification alters the bentonite crystal structure, enhancing its adsorption capacity for chloride ions. The addition of modified bentonite directly adsorbs chloride ions in high-chloride wastewater, further alleviating osmotic pressure stress from anaerobic microorganisms.

[0012] The third objective of this invention is to provide the dosage and method of adding the above-mentioned betaine and modified bentonite.

[0013] The dosage provided by this invention, when mixed with betaine to achieve a concentration of 0.5 mmol / L to 2.5 mmol / L and modified bentonite to achieve a concentration of 1 g / L to 10 g / L, is the most cost-effective dosage for treating high-chlorine wastewater with a chloride ion concentration of 6000 mg / L to 20000 mg / L.

[0014] The dosing method provided by this invention involves adding betaine and modified bentonite to the influent tank in sequence according to their respective concentrations, mixing them with the high-chlorine wastewater, and then thoroughly stirring and mixing before introducing the mixture into the anaerobic system. This method offers high raw material utilization, does not cause secondary pollution, is convenient to use, has high microbial utilization efficiency, and exhibits stable performance.

[0015] The objective of this invention is achieved by at least one of the following technical solutions.

[0016] This invention provides a method for enhancing the anaerobic biological treatment capacity of high-chlorine wastewater using betaine combined with modified bentonite. Specifically, any conventional anaerobic sludge is inoculated into the anaerobic reaction system, and the influent chloride ion concentration and influent flow rate are gradually increased to acclimate salt-tolerant sludge. Based on the influent flow rate, an appropriate amount of betaine and modified bentonite are added to the influent tank and uniformly mixed with the high-chlorine wastewater before being introduced into the anaerobic biological treatment system for full reaction, thereby improving the treatment effect of high-chlorine wastewater.

[0017] Preferably, the anaerobic biological treatment system includes conventional anaerobic digesters, two-phase anaerobic digesters, membrane bioreactors represented by anaerobic biofilters, upflow anaerobic sludge beds, expanded granular sludge beds, and internal circulation anaerobic reactors, etc.

[0018] Preferably, the betaine includes one or more of industrial-grade 99% pure anhydrous betaine and 99% pure monohydrate betaine.

[0019] Preferably, the modified bentonite comprises one or more modified products made from one or more of industrial-grade sodium-based bentonite and industrial-grade calcium-based bentonite, soaked in 0.5mol / L to 2mol / L NaOH for 1h to 3h, dried, and then calcined at 500℃ to 650℃ for 2h to 4h.

[0020] Preferably, the amount of betaine added is 0.5 mmol / L to 2.5 mmol / L.

[0021] Preferably, the dosage of the modified bentonite is 1 g / L to 10 g / L.

[0022] Preferably, the chloride ion concentration in the high-chlorine wastewater ranges from 6000 mg / L to 20000 mg / L, and the COD ranges from 200 mg / L to 5000 mg / L.

[0023] This invention reveals that the combined addition of betaine and modified bentonite has significant practical application value. On one hand, betaine accumulates within anaerobic microbial cells, alleviating osmotic pressure stress caused by high-chlorine environments, enhancing microbial activity, promoting the secretion of extracellular polymers, and strengthening the adsorption of chloride ions in wastewater. On the other hand, the addition of modified bentonite directly adsorbs chloride ions in high-chlorine wastewater, further alleviating osmotic pressure stress on anaerobic microorganisms. Although betaine and modified bentonite have different mechanisms of action, their combined addition achieves synergistic effects, jointly improving the anaerobic biological treatment of high-chlorine wastewater.

[0024] Furthermore, after adding betaine and modified bentonite, and then carrying out sufficient anaerobic fermentation treatment (here, sufficient refers to a hydraulic retention time of more than 6 hours), the effect of anaerobic biological treatment of high-chlorine wastewater can be significantly improved. The COD removal rate of high-chlorine wastewater reaches more than 70%, and the chloride ion removal rate of high-chlorine wastewater reaches more than 15%.

[0025] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0026] (1) This invention can be adapted to the anaerobic biological treatment process that is currently in operation in most sewage treatment plants in my country, and does not require the reconstruction of treatment facilities. It only requires the addition of a dosing device and can be achieved without shutdown.

[0027] (2) The raw materials of this invention, betaine and bentonite, are widely available in nature, have no impact on the environment, have mature production processes, and are low in cost. Betaine is easily soluble in water, and modified bentonite is in powder form, which is convenient to mix with high-chlorine wastewater.

[0028] (3) The method proposed in this invention, which utilizes betaine and modified bentonite to enhance the salt tolerance of anaerobic sludge and thus improve the anaerobic treatment of high-chlorine wastewater, has a significant effect on high-chlorine wastewater with chloride ion concentrations ranging from 6000 mg / L to 20000 mg / L. The dosage corresponding to different chloride ion concentrations of wastewater can be determined by simple preliminary experiments. Attached Figure Description

[0029] Figure 1 This diagram illustrates the COD removal effect of betaine applied in the anaerobic digestion bottle device of this invention in the treatment of high-chlorine wastewater.

[0030] Figure 2 This diagram illustrates the effect of betaine from the present invention on chloride ion removal in the treatment of high-chlorine wastewater using an anaerobic digestion bottle device.

[0031] Figure 3 This diagram illustrates the effect of applying the present invention to the anaerobic digestion bottle device for treating high-chlorine wastewater.

[0032] Figure 4 This image shows the COD removal effect of the present invention in the anaerobic treatment of artificially simulated high-chlorine wastewater.

[0033] Figure 5 The graph shows the COD removal rate and chloride ion removal effect of the present invention in the actual anaerobic treatment of high-chlorine wastewater in a factory.

[0034] Figure 6 This image shows the COD removal effect of the present invention applied to the anaerobic treatment of a real high-chlorine pharmaceutical wastewater.

[0035] Figure 7 The diagram shows the effect of this invention on chloride ion removal in the anaerobic treatment of a real high-chlorine pharmaceutical wastewater. Detailed Implementation

[0036] The specific embodiments of the present invention will be further described below. It should be noted that the description of the embodiments is for the purpose of aiding understanding the present invention, but does not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] Example 1

[0038] Six parallel experiments were set up, using anaerobic digestion flasks as small reactors placed in a constant-temperature incubator at 30℃ for 72 hours. The sludge source was acclimated sludge from an anaerobic deep reaction tower at a wastewater treatment plant. Laboratory-simulated high-chlorine wastewater was used as the treatment sample, with NaCl used to control the chloride ion concentration, maintaining an initial COD concentration of 2500 mg / L and an initial chloride ion concentration of 10000 mg / L. Different amounts of betaine were added, and after addition, the digestion flasks were sealed. Nitrogen gas was introduced through the left air inlet for 3 minutes to create an anaerobic environment before sealing and conducting the experiment.

[0039] Six parallel experimental groups were set up, maintaining consistent initial COD and chloride ion concentrations across groups. Different concentration gradients of betaine (0, 0.5, 1.0, 1.5, 2.0, and 2.5 mmol / L) were used, along with sodium bicarbonate as a pH buffer to ensure a neutral pH in the anaerobic flasks, thus maintaining good methanogenic activity during the culture period. After 72 hours of cultivation, the experimental results are shown in Table 1. The experiment revealed that the betaine-added groups showed significantly improved COD and chloride ion removal rates, with the 2 mmol / L group exhibiting the best results. Figure 1 As shown, the COD removal rate reached 60.83%; Figure 2 As shown, the chloride ion removal rate reached 8.63%. Comparative analysis results indicate that the addition of betaine can play a significant positive role in the survival of anaerobic bacteria in a high-chlorine environment.

[0040] Table 1 Comparison of the effects of different concentrations of betaine on the improvement of anaerobic treatment of high-chlorine wastewater

[0041]

[0042] Example 2

[0043] Using anaerobic digestion bottles as small reactors, four parallel experiments were set up. The specific implementation conditions were the same as in Example 1. Based on existing experimental results, 2 mmol / L betaine was added to all experimental groups, along with the same concentration (5 g / L) of modified adsorbent (bentonite, kaolin, and diatomaceous earth). After 72 hours of incubation, the treatment effects were as follows: Figure 3 As shown in the figure. Analysis results revealed that the COD removal rate in the experimental group with 5 g / L modified bentonite reached 72.26%, an increase of over 10% compared to the experimental group with only betaine added in Example 1. The chloride ion removal rate reached 12.39%, an increase of approximately 5%. The results indicate that modified bentonite is the most effective of the three modified adsorbents and does not conflict with the action of betaine. Combined addition can have a significant positive effect on the survival of anaerobic bacteria in a high-chlorine environment.

[0044] Example 3

[0045] An internal circulation anaerobic reactor was constructed in the laboratory. The sludge was taken from granular sludge from an internal circulation anaerobic reactor at a company in Guangzhou.

[0046] Artificial high-chlorine wastewater was used, with a COD:N:P ratio of 200:5:1. Glucose was used as the carbon source, NH4Cl as the nitrogen source, and KH2PO4 as the phosphorus source. NaCl was used to control the chloride ion concentration. Initially, the glucose concentration in the artificially prepared water was 2000 mg / L, which was increased to 3000 mg / L after an adaptation period (7 days). The dosages of other inorganic salts in the artificially simulated high-chlorine wastewater were: NH4Cl 286 mg / L, KH2PO4 42 mg / L, K2HPO4 21 mg / L, and MgSO4 and FeSO4 both 12.5 mg / L. To maintain good microbial growth, Fe was also added. 2+ Mn 2+ Co 2+ Mo 2+ Trace elements (see Table 2 for trace element formulas) are added, and NaHCO3 is added according to the reactor conditions to adjust the pH of the influent to maintain the internal pH of the reactor between 6.8 and 7.2.

[0047] Table 2. Trace Element Composition Table

[0048]

[0049] A 150-day application experiment was conducted, with nine salinity gradients (as NaCl) set at 1, 2, 4, 6, 8, 10, 12, 16, and 20 g / L, corresponding to chloride ion concentrations of 600, 1200, 2400, 3600, 4800, 6000, 7200, 9600, and 12000 mg / L, respectively. The reflux ratio and volumetric loading were adjusted based on changes in effluent COD and chloride ion concentration. The COD removal effect was as follows: Figure 4 As shown in the figure, the analysis results reveal that with increasing salinity, the degradation of COD in the anaerobic reactor for high-chlorine wastewater shows a decreasing trend. However, due to natural selection, the anaerobic bacteria gradually adapt to the high-chlorine environment, resulting in slight fluctuations in treatment efficiency. The treatment efficiency significantly decreases when the salinity reaches 20 g / L (chloride ion concentration 12000 mg / L). At this point, continuous mixing with simulated wastewater and adding 0.5 mmol / L of industrial-grade 99% pure anhydrous betaine and 1 g / L of modified bentonite, followed by stable operation for 25 days, shows a significant rebound in COD removal efficiency after betaine addition, reaching nearly 70%. These results demonstrate that the combination of betaine and modified bentonite enhances the anaerobic biological treatment of high-chlorine wastewater.

[0050] Example 4

[0051] Anaerobic biological treatment was implemented for the high-chlorine wastewater from a chemical plant, and the treatment effect was improved by adding betaine and modified bentonite. The water quality indicators of the high-chlorine wastewater are shown in Table 3.

[0052] Table 3. Main water quality indicators of high-chlorine wastewater

[0053]

[0054] For the aforementioned high-chlorine wastewater, a multi-point reflux two-phase anaerobic deep reactor was constructed. The reactor consists of two parts: a pre-hydrolysis tower and an anaerobic deep reaction tower. The pre-hydrolysis tower has the following specifications: φ = 3m, H = 7m, and an effective volume of 56m³. 3 ; Specifications of the anaerobic deep reaction tower: φ=2m, H=5m, effective volume 18m³ 3 HRT = 8h. Salt-tolerant anaerobic sludge that has been acclimated is used in the reactor. The reactor operates intermittently, with 12 hours of influent per day, maintaining an internal circulation with a reflux ratio of 3 in the anaerobic deep reactor. The temperature is maintained at 37±2℃, and the influent pH is 7.0±0.5.

[0055] A 75-day anaerobic biological treatment experiment was conducted, with water samples collected daily for testing. Changes in COD removal rate and chloride ion removal rate were recorded as follows: Figure 5 As shown, due to the large fluctuations in water quality and the excessively high chloride ion concentration in the wastewater, the activity of anaerobic microorganisms was inhibited, resulting in a COD removal rate of only about 30% and a chloride ion removal rate of less than 5% in the initial stage of treatment. When the reactor had been running for 35 days, the high-chlorine wastewater quality experienced drastic fluctuations, with the influent COD reaching over 1600 mg / L and remaining above this level for about a week. Therefore, the COD removal rate remained low during this week. At this point, the influent-effect reflux ratio of the reactor was adjusted to ensure normal system operation. After the influent water quality stabilized, the COD removal rate rebounded to about 45%. On day 55, 2.5 mmol / L of industrial-grade 99% pure betaine monohydrate and 10 g / L of modified bentonite were added based on the influent flow rate. Stable operation for 20 days was maintained. The experimental results show that during these 20 days, both COD and chloride ion removal showed an upward trend, with the COD removal rate remaining above 70%, reaching a maximum of 75%, and the chloride ion removal rate also increasing to 20%. The above results indicate that the addition of betaine and modified bentonite can improve the anaerobic treatment effect on actual high-chlorine wastewater, even under conditions of drastic water quality fluctuations. Within the concentration range described in this invention, increasing the dosage of betaine and modified bentonite can further enhance the removal rates of COD and chloride ions in high-chlorine wastewater through anaerobic biological treatment. Under optimal conditions, the removal rates of COD and chloride ions in high-chlorine wastewater reach 75% and 20%, respectively.

[0056] Example 5

[0057] An anaerobic system was constructed for a high-chlorine pharmaceutical wastewater treatment project undertaken by a wastewater treatment plant. The reactor structure was consistent with that in Example 4. Sludge was taken from the end of the secondary sedimentation tank of the biochemical treatment system of the wastewater treatment plant, with a sludge volume of 50 tons, of which 30 tons were added to the hydrolysis acidification tower and 20 tons to the anaerobic tower. After the sludge addition was completed, actual high-chlorine pharmaceutical wastewater influent commissioning was carried out. Using the method of this invention, 2 mmol / L of industrial-grade 99% pure anhydrous betaine and 5 g / L of modified bentonite were added to the influent to enhance the activity of the anaerobic sludge in a high-chlorine environment, controlling the daily treated water volume to 25 m³. 3 / d, hydraulic retention time 6h.

[0058] Analysis of 30 sets of valid data shows the changes in effluent COD as follows: Figure 6 As shown in the figure. It can be observed that, after treatment by the method of this invention, the COD degradation rate of high-chlorine pharmaceutical wastewater generally remains above 50%, which is 10% higher than the current anaerobic treatment effect at the plant. The changes in chloride ion concentration are shown in the figure. Figure 7 As shown, under the conditions of continuous addition of betaine and modified bentonite, the anaerobic sludge maintained a consistently high level of chloride ion removal. Statistical analysis of the average values ​​of thirty samples revealed an average removal rate of 11.83%, with a maximum of 17.09%, representing an increase of over 10% compared to the original anaerobic stage removal rate of the plant. This is because the addition of betaine plays a positive role in the adaptation of anaerobic bacteria to a high-chloride environment, increasing the secretion of extracellular polymers in the anaerobic sludge. These extracellular polymers, due to their compact structure and surface-carrying micro-charges, adsorb inorganic ions. Additionally, the addition of modified bentonite also adsorbs a large amount of chloride ions. The synergistic effect of these two factors enhances the activity of anaerobic microorganisms in a high-chloride environment.

[0059] The above embodiments are merely preferred embodiments of the present invention and are only used to explain the present invention, not to limit the present invention. Any changes, substitutions, or modifications made by those skilled in the art without departing from the spirit and essence of the present invention should be within the protection scope of the present invention.

Claims

1. A method for enhancing the capacity of anaerobic biological treatment of high-chlorine wastewater by using betaine in combination with modified bentonite, characterized in that, It comprises the following steps: Anaerobic sludge is inoculated into an anaerobic reaction system, salt-tolerant sludge is domesticated by gradually increasing the chloride ion concentration and the influent amount of the influent, and after the domestication of halophilic bacteria is completed, a corresponding amount of betaine and modified bentonite is added in the influent tank according to the influent flow, and after being uniformly mixed with high-chlorine wastewater, it is introduced into the anaerobic biological treatment system for sufficient reaction, so as to improve the treatment effect of high-chlorine wastewater; The chloride ion concentration in the high-chlorine wastewater ranges from 6000 mg / L to 20000 mg / L; The betaine is selected from one or more of industrial-grade 99% purity anhydrous betaine and 99% purity monohydrate betaine; the addition amount of betaine is 0.5 mmol / L to 2.5 mmol / L; The preparation method of the modified bentonite is as follows: the bentonite raw material is soaked in 0.5 mol / L to 2 mol / L NaOH for 1 h to 3 h, then the bentonite is separated by filtration, and after natural drying, it is continuously calcined at a temperature of 500℃ to 650℃ for 2 h to 4 h to obtain the alkali-modified and calcined modified bentonite; the addition amount of the modified bentonite is 1 g / L to 10 g / L.

2. The method for enhancing the ability of anaerobic biological treatment of high-chlorine wastewater by using betaine combined modified bentonite according to claim 1, characterized in that, The bentonite raw material is selected from one or more of industrial-grade sodium-based bentonite and industrial-grade calcium-based bentonite.

3. The method for enhancing the ability of anaerobic biological treatment of high-chlorine wastewater by using betaine combined modified bentonite according to claim 1, characterized in that, The addition method is as follows: the betaine and the modified bentonite are sequentially added to the influent tank according to the corresponding concentration, and after being uniformly mixed by stirring, they are introduced into the anaerobic system.

4. The method for enhancing the ability of anaerobic biological treatment of high-chlorine wastewater by using betaine combined modified bentonite according to claim 1, characterized in that, The high-chlorine wastewater contains organic matter for normal growth of anaerobic microorganisms, and the COD concentration in the high-chlorine wastewater ranges from 200 mg / L to 5000 mg / L.

5. The method for enhancing the ability of anaerobic biological treatment of high-chlorine wastewater by using betaine combined modified bentonite according to any one of claims 1-4, characterized in that, The anaerobic biological treatment system includes one of ordinary anaerobic digestion tank, two-phase anaerobic digestion reactor, membrane bioreactor represented by anaerobic biofilter, upflow anaerobic sludge bed, expanded granular sludge bed and internal circulation anaerobic reactor.

Images