RU2751356C1 - Method for removing nitrogen-containing compounds from wastewater - Google Patents

Abstract

FIELD: wastewater treatment.

SUBSTANCE: invention relates to the field of wastewater treatment and can be used at municipal sewage treatment plants, at chemical plants, for the treatment of effluents from livestock and poultry complexes, in household organic waste treatment. The method for removing nitrogen-containing compounds from wastewater involves treating wastewater under aerobic-anaerobic conditions in a reactor equipped with an attached biocenosis carrier - Anammox activated sludge. The supply of waste water to the reactor of cyclic action is carried out within 30 minutes after 20 minutes of settling. Waste water is treated while maintaining the temperature in the reactor at a level of 32 ± 0.1°C for 5 hours and 10 minutes with alternating (20 minutes each) aeration with large air bubbles and stirring with a stirrer at 120-150 rpm. The full cycle time is 6 hours. The air supply rate at the time of start-up is 20 l / h, the oxygen content in the reactor varies in the range of 0.4-1.2 mg / l. Wastewater is treated in the presence of additives of metabolites selected from folic acid (folate) taken at a concentration of 50-100 mg / l or folic acid (folate) taken at a concentration of 0.1-0.5 mg / l.

EFFECT: invention provides an increase in the stability of wastewater treatment, as well as reduction in the time of attachment of Anammox activated sludge to the carrier, i.e. shortens the start-up period of new bioreactors using the Anammox activated sludge fixed biomass technology and the duration of the process in general.

6 cl, 3 dwg, 2 tbl, 4 ex

Description

The invention relates to the field of wastewater treatment, namely the purification of wastewater from nitrogen. The invention can be used in municipal wastewater treatment plants using the technology of fermentation of sewage sludge, at industrial enterprises, for the treatment of effluents from livestock and poultry complexes, anaerobic bioreactors for the processing of domestic organic waste, as well as in the chemical industry.

Currently, the most effective technology for removing nitrogen compounds from wastewater in terms of cost, minimum area occupied by a bioreactor, and energy consumption is the Anammox-type technology. Such technologies are based on the biochemical process of ammonium oxidation by nitrite in anoxic conditions (Anaerobic Ammonia Oxidation). Technologies such as Anammox are the youngest block of wastewater treatment technologies (the first industrial implementation took place in 2005, and today more than 100 units are already operating). These technologies are developing and being actively improved in different directions - hardware, technological, conceptual. Currently, various technological schemes using Anammox bacteria have been developed and put into practice: DEMON, SHARON-ANAMMOX, ANITA-Mox, DeAmmon, OLAND, Canon, Deammox, DeAmmon, OLAND, SNAP, SAD, PANAM and others (Kumwimba et all. , Anammox-based processes: How far have we come and what work remains, A review by bibliometric analysis Chemosphere 238 (2020) 124627).

There is a known method for removing ammonium from wastewater, flowing under anoxic (oxygen-free, but with an oxidizing agent alternative to oxygen) conditions and carried out by a group of specific bacteria, in which ammonium is oxidized by nitrite (for example, US 5078884). In the mentioned and similar methods of wastewater treatment (see US 5259959, US 6485646, US 20060191846, WO 1998007664, WO 2013151836 Al, WO 2011110905), two successive processes are used - aerobic oxidation of a part of ammonium to nitrite, then biological denitrification, the actual Anammox process with using nitrite as an oxidizing agent, and ammonium as an electron donor with the participation of specific anaerobic microorganisms (anammox bacteria). Thus, the Anammox technological process consists of two independent, but connected in a single technological process, blocks: nitrification (oxidation of ammonium to nitrite), and the Anammox process itself, the oxidation of ammonium with nitrite. These processes can be carried out in different reactors or in one. The one-pot version is more common, because has a number of advantages, in particular - higher specific rates of nitrogen removal, as well as a small volume of bioreactors. In particular, one of the technologies based on the process of autotrophic ammonium oxidation by nitrite is the one-pot Demon technology (RU 2530060, 10.10.2014).

In the Anammox technology, the biomass retention process is essential, because Anammox bacteria are one of the slowest growing microorganisms on Earth. To retain the biomass of Anammox activated sludge in the reactor, the following are used: traditional gravity sedimentation of free-floating sludge (flocculated or granular), separation of sludge on cyclones, retention of activated sludge on floating or stationary carriers of the attached biocenosis ("loads").

Cleaning using a floating charge is described in RU 2584574, 05/20/2016, where the process of removing ammonium nitrogen is carried out in a one-pot process in different layers of biofilm formed on the elements of the moving charge. However, when using a floating load, there is a risk of its loss (together with activated sludge) due to an abnormal or emergency situation, which at a slow rate of growth of the active biomass of Anammox sludge means a loss of reactor productivity or a decrease in the quality of wastewater treatment while maintaining water consumption.

This disadvantage (the probability of losing a part of the Anammox biomass) is lacking in technologies in which the biomass is attached to a stationary carrier. For example, there is a known method for purifying wastewater from ammonium and organic matter and an installation for its implementation, where for purification in aerobic-anoxidic conditions, proceeding simultaneously, it is proposed to use the biomass of activated sludge containing specific microorganisms cultivated in a bioreactor and adapted to the conditions of the water purification method (RU 2630238 06.09.2017).

The disadvantage of the known solution is the instability of the first technological stage - the stage of partial nitrification. The scientific literature has repeatedly noted that the nitrification stage is very sensitive to changes in process parameters, the presence of toxicants, leading to a disruption of the nitrogen removal process as a whole (for example, Ma et all., Biological nitrogen removal from sewage via anammox: Recent advances Bioresource Technology 200, 2016, P. 981-990).

It is known from the literature that a significant drawback of the Anammox technology is the slow growth of Anammox bacteria, which leads to a long period of starting the process due to the need to build up a sufficient amount of activated sludge. Process equipment can take up to two years to reach its design capacity (Van Der Star et al., Startup of reactors for anoxic ammonium oxidation: experiencesfrom the first full-scale anammox reactor in Rotterdam. Water Res. 2007. V. 41. P. 4149-4163).

To accelerate the launch of the activity of Anammox bacteria, the use of hydrazine or hydroxylamine supplements is known (Adams et all., The effect of carrier addition on Anammox start-up and microbial community: a review Rev Environ Sci Biotechnol, 2020, https://doi.org/ 10.1007 / s11157-020-09530-4).

However, there is no information about the substances-stimulants of bacteria-nitrifiers, which could be used for technological purposes, in the mentioned sources of information.

The closest technical solution, which we have chosen as a prototype, is described in the article: "Creation of the first technology of the Anammox type in Russia" (Nikolaev et al., Water supply and sanitary equipment, No. 8, 2017, pp. 28-33). A known method for removing nitrogen compounds from wastewater involves treating wastewater under aerobic-anaerobic conditions in a reactor equipped with an attached biocenosis carrier - Anammox activated sludge. The method provides for keeping the Anammox biofilm on a flat stationary carrier, the presence of a stage of additional oxidation and grinding of activated sludge containing specific anammox bacteria (Candidatus Jettenia mocvienalis). The known method makes it possible to reduce the duration of the launch of the process at the design capacity up to 10 months.

However, the disadvantage of the known method is the instability of the purification process under conditions of a sharp increase in the concentration of pollutants in the water being purified and also the duration of the period of attachment of Anammox activated sludge to the carrier.

The task of the proposed technical solution is to develop a method for removing nitrogen compounds from wastewater, characterized by increased process stability while reducing the duration of the attachment period of the Anammox activated sludge to the carrier, which directly contributes to reducing the time the reactor reaches its maximum productivity.

The technical result of our invention is to increase the stability of the method, in particular - in stressful conditions of its implementation, and increase the productivity of the process as a whole by reducing the duration of the start-up stage. In addition, the invention expands the range of cleaning methods using the Anammox technology.

The problem is solved by the described method for removing nitrogen compounds from wastewater, including the treatment of wastewater under aerobic-anaerobic conditions in a reactor equipped with an attached biocenosis carrier - Anammox activated sludge, in the presence of additives of metabolites selected from formic acid (formate) taken at a concentration of 50 -100 mg / l or folic acid (folate) taken at a concentration of 0.1-0.5 mg / l.

Preferably, the water purification is carried out in a one-pot scheme in a batch reactor (SBR-type reactor).

Preferably, the Anammox activated sludge carrier is made of a polymeric material with a developed surface.

Preferably, the extended surface polymeric material is a fibrous nonwoven fabric formed from a blend of polyethylene and polypropylene.

Anammox activated sludge can be preformed in another bioreactor under conditions similar to those in a running working reactor, and then fixed on a carrier of an attached biocenosis, or formed directly in a working reactor.

On the day of stabilization of the process, folate or formate can be fed both at the time of the onset of stressful conditions and preventively at the time of inoculation of the bioreactor with activated sludge.

The above set of features included in the independent claim is not known from the prior art. Within the scope of the above set of features, the claimed technical result is achieved, which is confirmed below. Neither in the scientific and technical, nor in the patent literature, we found information about the possible influence of the distinctive features of the independent claim (the introduction of additives of the above metabolites in the declared amount) on the technical result achieved when implementing the claimed method.

It can be noted that in the method according to SU 546468, which provides for the biological treatment of wastewater from the pulp and paper industry from organic substances determined by BOD, it is recommended to introduce activated sludge and a biostimulator into the aerotank in the form of a composition containing 11 different vitamins, one of which is folic acid ... As you can see, the known technical solution is aimed at solving a different problem and at achieving a different result (reducing the volume of the aeration tank and accelerating the biooxidation process), in relation to another group of activated sludge microorganisms (heterotrophic aerobic bacteria).

In addition, there is a known method for biological treatment of wastewater containing formaldehyde production waste using activated sludge during flow cultivation, where formaldehyde and folic acid are introduced as an additive in an amount of 0.001-0.01 mg / l (SU 1581703, 1990) ... The known method solves the problem of increasing the mass of sludge by stimulating the assimilation of formaldehyde by active sludge along the restorative pathway of metabolism. Thus, the introduction of folic acid in the known solution provides a different metabolism of the process and, accordingly, a different technical result.

The essence of the proposed invention is further illustrated using examples 1-4.

The process flow diagram is shown in Fig. 1. The results of the implementation of the method are shown in FIG. 2 and 3.

FIG. 1 shows one of the possible installation schemes for implementing the method, where the corresponding position numbers indicate the following units:

1 - reactor-fermenter (1A - inner part containing activated sludge and purified water, 1B - outer part, thermostatically controlled jacket),

2 - tank for treated waste water,

3 - a container with water for dilution,

4 - magnetic stirrer,

5 - compressor,

6 - peristaltic pump,

7 - stirrer magnet,

8 - suspension for the magnet,

9 - the carrier of the attached biocenosis,

10 - fitting for supplying heated water to the thermoregulation circuit,

11 - nozzle of purified water discharge.

FIG. 2 shows the dynamics of nitrogen removal (A), the efficiency of nitrogen removal (B), and the contribution of the deammonification process to nitrogen removal (C) during the experiment with the addition of folate and formate.

FIG. 3 shows the dynamics of the attachment of Anammox activated sludge on the carrier of the attached biocenosis (loading material) in the presence of biologically active additives: formate and folic acid.

Our choice of metabolites is due to the following. According to our analysis of the metagenome of anammox communities of activated sludge, anammox bacteria cannot synthesize folic acid themselves (an intermediate in the synthesis of nucleic acids), but formate ensures their autotrophic growth. ) nitrogen removal process.

To implement the method using activated sludge, fixed on a carrier of an attached biocenosis, and to check the effect of the proposed additives on the Anammox process, a bioreactor was used, consisting of three identical autonomous SBR-type bioreactors. A single reactor (fermenter) contains two coaxial cylinders made of polymethyl methacrylate. The space between the outer cylinder and the inner one is hermetically sealed; it is used for thermostating the reactor.

For this, two fittings are cut into the outer walls, allowing water to pass in a continuous mode at a given temperature. Four more fittings are cut into the side walls of the inner cylinder - two at the bottom and at the surface: for supplying and draining water and for taking samples. The working volume of the fermenter reactor is 4.5 liters.

As an activated sludge capable of carrying out the Anammox process, we used activated sludge from a reactor carrying out the Anammox process and containing all the necessary groups of microorganisms, such as nitrifiers of the first group, anammox bacteria and others (Mardanov et al., Dynamics of composition changes microbial consortium in the process of launching a one-pot flow laboratory installation of nitritation / Anammox // Microbiology. 2016. T. 85. No. 6. P. 663-675.). Therefore, in the following examples, the general concept of "anammox community or activated sludge" is used.

Quantities, i.e. the concentration of additives of metabolites: formic and folic acids have a significant impact on the achievement of the stated result. We have experimentally established the necessary concentration intervals for each of the additives, which provide, on the one hand, the stability of the process, and on the other hand, reduce the duration of the initial stage of the process - attachment of activated sludge to the feed. A decrease in the concentration of the additive below the declared value leads to a decrease in the achieved technical results: the adhesion time of activated sludge by 20-50% and the efficiency of ammonia removal by 10-15%. Exceeding the concentration of additives above the stated value is impractical, since it increases the cost of operating costs for wastewater treatment.

The following example 1 was carried out in the conditions of the prototype, i.e. without the introduction of additives of metabolites.

Examples 2-3 were carried out under the conditions of example 1, but in the presence of additives of the claimed metabolites, with optimal concentrations of formic and folic acids in the middle of each of the stated intervals.

Example 1 - comparative (without the addition of metabolites).

Inside the reactor-fermenter (position 1A in Fig. 1) is placed a carrier made in the form of a rigidly fixed cylindrical load made of fibrous nonwoven material (9) made from a mixture of polyethylene and polypropylene (porous-fibrous carrier of the attached biocenosis "Polivom", OOO NPF " ETEK LTD ") (D _Int . = 85 mm, h = 200 mm, m = 82 g, total surface area (on both sides) - 11.6 dm ² , the volume of the feed material was 6% of the working volume of the reactor). A compressor (5) supplies air to the bottom of the fermenter. The unit used coarse bubble aeration to provide more efficient mixing. During the period without aeration, stirring was provided using a magnetic stirrer (4, 7, 8). The feed solution was supplied by peristaltic pumps (6). The feed solution fed to the bottom of the fermenter displaces the treated water through the top outlet. During this period, the solutions are practically not mixed, since the supplied solution is colder by 5 ° C and more than the solution in the fermenter. The pilot plant contains three structurally identical fermenter reactors. A Masterflex L / S economy drive peristaltic pump was used to supply the feed solution. In order to synchronize the supply, the drive was equipped with three Easy-Load nozzles with a Norprene hose 6404-13, which made it possible to simultaneously supply the solution to all three fermenters. Water for dilution was supplied with a Masterflex L / S economy drive pump with a High-Performance nozzle with a Norprene hose 06404-15, one pump per fermenter. Magnetic stirrers IKA C-MAG MS7 (4) were used for stirring, and a SCHEGO SW2 compressor (5) was used for air supply. The temperature regime was set using an ELMI TV 2.03 thermostat bath, which is equipped with a circulation pump for the external circuit. An Oxi 7310 WTW oximeter was used to monitor the oxygen content. Automation was carried out using a Siemens LOGO 6ED1 programmable timer.

The three fermenter reactors were operated in the same mode throughout the experiment. Full cycle time - 6 hours. After 20 min of settling, 1 L of a solution simulating waste water was fed for 30 min. Only 4 liters per day. Then for 5 hours 10 minutes the fermenter was alternately (20 minutes each) aerated or stirred. Thus, taking into account the working volume of 4.5 liters, the average residence time of the solution in the fermenter was 27 hours. The air was supplied in large bubbles so that silt did not accumulate at the bottom. Stirring with a magnetic stirrer was carried out at 120-150 rpm. The temperature was maintained at 32 ± 0.1 ° C. At the time of start-up, the air supply rate was 20 l / h; during the experiment, it was increased as the biomass increased. The oxygen content in the fermenters varied in the range of 0.4-1.2 mg / l, increasing with the accumulation of bacterial biomass. The feed rate was controlled by a rotameter.

The composition of the model solution simulating waste water that enters the reactor contains (g / l): (NH4) ₂ SO ₄ - 0.942; NaCH ₃ COO x 3H ₂ O -0.04; KH ₂ PO ₄ 0.044; NaHCO ₃ 2.1; pH 8.3. The model solution fed into the reactor was obtained by mixing the concentrate-saline solution (2) and tap water (3) immediately before feeding into the fermenter.

In the examples with the filing of the claimed additives: folate and formate, they were introduced into the waste water concentrate. As a result of biochemical processes occurring in the bioreactor, the pH decreased to values of 7.7-8.2.

The concentration of ammonium, nitrite and nitrate ions in purified water was determined weekly by standard methods. Based on the data obtained, to assess the effectiveness of the method, the following derived values were calculated: ΔΝ (the amount of removed nitrogen (as the difference in the concentration of mineral forms of nitrogen in purified water (NH ₄ , NO ₂ , NO ₃ ) and in incoming water (NH ₄ ), expressed in mg / L and %%, as well as dN _{Deammonification} (the proportion of nitrogen removed during autotrophic and heterotrophic deammonification - anammox process and with the participation of denitrifying bacteria, calculated as the ratio of the amount of nitrogen removed from the reactor, ΔΝ, to the amount of ammonium nitrogen removed ΔΝ -NH ₄ ).

This example illustrates the technical feasibility of implementing the proposed method in a specific purification scheme, but is not limited to using only the described installation.

Example 2. An experiment on the effect of additives, folate and formate, on the process of removing nitrogen-containing contaminants under conditions of a sharp increase in the concentration of ammonium ions, was carried out in the reactor described in example 1, with similar process parameters.

For the inoculation of three reactors, Anammox activated sludge was used, which was cultivated earlier in the Anammox reactor with a similar technological regime. Each reactor was loaded with 3.8 g of Anammox activated sludge on a dry matter basis. Anammox activated sludge adhered to the loading carrier within 3 weeks. During the entire period of operation, the amount of suspended particles was below 0.2 g / L. Obviously, they were represented by the sloughing biomass of Anammoxil. Thus, the mass of free-floating sludge was no more than ¼ of the mass of sludge at the loading. During the first three weeks, the stability of technological parameters (air supply, operation of mixers, etc.) was also debugged, the stable operation of the reactors began from the 3rd week, which is reflected in Fig. 2. During the next stage, the stability and uniformity of the operation of the reactors was achieved, after which, on the 65th day, the concentration of ammonium in the incoming water was doubled, up to 400 mg / l, creating stressful conditions.

By the 65th day, all three reactors reached the same and high level of nitrogen removal - 82-85%. The absence of a significant increase in the efficiency of nitrogen removal indicates that, under these experimental conditions, the maximum ability of the anammox community to remove nitrogen has been reached (0.06 g N / day / dm ² load).

et al., Kinetic models for nitrogen inhibition in ANAMMOX and nitrification process on deammonification system at room temperature. Bioresource Technology. (2016). 202. P. 33-41.).On the 65th day, the nitrogen load was increased by increasing the ammonium concentration from 200 to 400 N-NH ₄ to create stressful conditions, since, despite the fact that ammonium is the main energy substrate, its high concentrations are toxic for both anammox bacteria, and for bacteria-nitrifiers of the first (nitroso) group (Aktan et al., Inhibitory effects of free ammonia on Anammox bacteria (2012). 23: 751-762; De

et al., Kinetic models for nitrogen inhibition in ANAMMOX and nitrification process on deammonification system at room temperature. Bioresource Technology. (2016). 202. P. 33-41.).

At the same time, formate (75 mg / ml) was added to one of the reactors in the waste water concentrate, and folic acid (0.2 mg / ml) was added to the other.

Immediately after the increase in the ammonium concentration, the activity of the community to remove nitrogen in the control variant decreased from 190 to 170 mg / L (by 10%), as well as in the presence of formic acid (by 15%) (Fig.2A), which confirmed the stress (unfavorable ) the nature of a sharp - two-fold increase in the concentration of ammonium. The presence of folate supported the community, and the drop in productivity was only 5%. At the same time, the magnitude of the removal efficiency decreased sharply for purely arithmetic reasons, since the denominator of the equation for its calculation has doubled (Fig. 2B). It is important to note that 3 weeks after the change in the cultivation regime, a sharp increase in the amount of removed nitrogen occurred only in the reactor with the addition of formic acid, which is explained by the development of the heterotrophic denitrification process, since in the presence of formate in the purified water the amount of nitrate immediately decreased by 3-5 times. This fact led to an increase in the dN _{Demonification index} (the proportion of nitrogen removed only during the deammonification process) in the reactor with the addition of formate (Fig. 2B).

Different concentrations of additives were tested for 93-107 days. On the 93rd day, the concentration of folate was reduced to 0.1 mg / L, formate - to 50 mg / L, at 100e - increased to 0.5 and 100 mg / L, respectively. These changes did not lead to significant changes in the performance of the reactors.

This example illustrates the possibility of complete attachment of Anammox activated sludge to the carrier of the attached biocenosis, as well as the possibility of using additives: formate and folate to stabilize the process of removing nitrogen from wastewater under stressful conditions.

Example 3. To test the effect of folate and formate on the adhesion rate of Anammox activated sludge on the loading carrier material and to test another mode of addition of folate and formate, constant during the operation of the reactor, another experiment was performed.

The activated sludge from the reactor described in Example 2 was flushed out of the feed and reintroduced into the three fermenters at 3.8 g / fermenter. The difference from the conditions described in Example 2 was that folate and formate were added along with the activated sludge. The dynamics of sludge sorption on the load is shown in Fig. 3. In the presence of additives, during the first week, 70-80% of the introduced sludge was sorbed on the loading, within two weeks almost all sludge was sorbed.

While in the control variant corresponding to the prototype, the sorption was worse - after 1 week less than half of the introduced sludge was attached, the sorption was completely completed after 4 weeks.

After establishing the same level of nitrogen removal in the reactors of 70-75% (day 50), the effect of different (higher and lower) concentrations of folate (0.1-0.5 mg / L) and formate (50-100 mg / L) on the efficiency of nitrogen removal was checked. ... In the specified ranges of concentrations, the efficiency of the Anammox process is at the same level.

On the 110th day, the ammonium concentration in the water supplied for treatment was increased to 500 mg / L (2.5 times), which led to unequal consequences in the efficiency of nitrogen removal from the reactors (Table 1). The mass of nitrogen removed increased in all variants, moreover, to the greatest extent - in the presence of folate and formate (by 47% and 37%, respectively), and according to the prototype method (control) - by 31%.

This example illustrates the following.

A) the application of folate and formate accelerates the attachment of activated sludge to the carrier of the attached biocenosis.

B) folate and formate can be used to stabilize the anammox process in the preventive feeding mode, i.e. before the onset of stressful conditions.

B) Comparison of the conditions of folate and formate administration (at the moment of stress or preventively) shows that administration together with the stressor has a greater protective effect, and the use of formate is somewhat more effective than folate.

Example 4. Evaluation of the effect of folate and formate on different groups of microorganisms.

The dynamics of changes in the concentrations of nitrogen compounds (ammonium, nitrite and nitrate) in the incoming and purified water of Anammox reactors before and after a sharp increase in ammonium entering the reactor, as well as the efficiency of nitrogen removal, are summarized in Table 2.

Table 2. Directions of changes in the concentrations of nitrogen compounds (ammonium, nitrite and nitrate) in the purified water of Anammox reactors after a sharp increase in ammonium entering the reactor, as well as the efficiency of nitrogen removal in the presence of additives relative to the control variant without additives.

Taking into account the presence of functional blocks of the Anammox community (ammonium-oxidizing bacteria, AHB, anammox-bacteria, ANC, nitrite-oxidizing bacteria, NOB, and nitrite- (and nitrate) -reducing bacteria, denitrifiers), it can be concluded that formate inhibits NOB and activates heterotrophic denitrifiers, and slightly and temporarily inhibits ANX bacteria (for a short time immediately after application); folate activates AHB and ANX.

The above examples proved that the introduction of folate and formate as metabolite additives in the stated concentration range provides a targeted change in the activity of various groups of bacteria, an increase in the efficiency of the process of removing nitrogen-containing contaminants by increasing the stability of the method and reducing the duration of the reactor startup stage in comparison with the prototype method.

The invention also makes it possible to expand the range of effective methods for purifying aqueous media using technology such as Anammox.

Claims (6)

1. A method for removing nitrogen-containing compounds from wastewater, including the treatment of wastewater under aerobic-anaerobic conditions in a reactor equipped with an attached biocenosis carrier - Anammox activated sludge, characterized in that the wastewater is fed into the cyclic reactor within 30 minutes after 20 minutes settling, waste water is treated while maintaining the temperature in the reactor at a level of 32 ± 0.1 ° C for 5 hours 10 minutes with alternating, 20 minutes each, aeration with large air bubbles and stirring with a stirrer at 120-150 rpm, full cycle time is 6 hours; the air supply rate at the time of start-up is 20 l / h, the oxygen content in the reactor varies in the range of 0.4-1.2 mg / l; wastewater is treated in the presence of additives of metabolites selected from formic acid (formate) taken at a concentration of 50-100 mg / l or folic acid (folate) taken at a concentration of 0.1-0.5 mg / l. 2. The method according to claim 1, characterized in that the water purification is carried out in a batch reactor (SBR type). 3. The method according to claim 1, characterized in that the carrier of the attached biocenosis is made of a polymeric material with a developed surface. 4. The method according to claim 3, characterized in that the carrier of the attached biocenosis is made in the form of a porous fibrous nonwoven material based on a mixture of polyethylene and polypropylene. 5. The method according to claim 1, characterized in that when the reactor is started up, Anammox activated sludge is used, previously formed in another bioreactor under conditions similar to those in the reactor being launched, or formed directly in the process of starting the reactor. 6. The method according to claim 1, characterized in that, to stabilize the process, folate or formate is fed at the time of the onset of stressful conditions or preventively at the time of inoculation.

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