A method of processing water containing sulphur compounds (options)

 

(57) Abstract:

The invention relates to 4 variants of the method of processing water containing sulfur compounds through biochemical oxidation of sulfide sulfur to elemental sulfur in the aerobic reactor in the presence of oxygen and biomass in the form of sulfidogenic bacteria. In the first embodiment, the number of sulfide entering the reactor per unit time, the nitrogen content in the biomass of at least 10 mg of sulfide per mg of nitrogen per hour. In the second embodiment, in the processing of sulphide-containing water in the presence of organic contaminants quantity of sulfide entering the reactor per day, is at least 10 g per 1 m2the surface of the biomass. To prevent the growth of filamentous bacteria type Thiothrix and Beggiafoa 3 version number sulfide entering the reactor is at least 25 sulfide on 1 l of the content in the reactor per hour, with a part of the sulfide oxidizes to sulfur, and formed in the reactor liquid after separation of the sulphur is directed to the second stage of aerobic oxidation to sulfate. 4 embodiment, in the processing of water containing or sulfate, or sulfite, or thiosulfate, or a mixture thereof, or tetrathionate, or elemental sulfur, or compounds of the pouring of bacteria to the recovery of sulphur compounds to sulphide with subsequent oxidation of the sulfide. At simultaneous presence in the water of heavy metal ions on stage anaerobic treatment of water content of sulfur compounds in terms of elemental sulfur to a concentration of heavy metal ions support required for complete precipitation of heavy metal ions in the form of sulphides. 4 C. and 12 C.p. f-crystals, 6 PL. 3 Il.

The invention relates to the field of processing water containing sulfur compounds. In particular, this invention relates to a process for processing water containing sulfide or containing sulfur compounds with higher oxidation States, such as sulfate, sulfite and thiosulfate, this water may also contain organic matter, according to this process, the sulfur compounds are oxidized in the reactor using pulp (biomass) containing aerobic bacteria.

The presence of sulfur compounds such as sulfide in the wastewater has many adverse consequences, such as:

the effects of corrosion on steel and concrete,

high chemical oxygen demand (COD), leading to oxygen depletion in the receiving water after the discharge into it of wastewater, including environmental pollution and/or high nalty smell.

Although the sulfide can be removed from waste water by chemical oxidation, desorption and deposition, are increasingly important biological treatment methods. The biological removal of sulfide can be carried out using phototrophy sulfur bacteria (also accompanied by the production of sulfur) and by denitrification bacteria. The sulfide can also be broken into sulphide by bacteria that consume oxygen in the activated sludge. The sulfur production using bacteria that consume oxygen, has advantages over using phototrophic bacteria as aerobic transformation occurs much faster than anaerobic (footrope) transformation, and flow of light in the sulfur reactor dense gas environment is not an easy task, while oxygen may be fed into the aerobic reactor in a simple way without problems. In the case of denitrifying bacteria necessary nitrate.

The advantages of the conversion of sulfide to sulfur, not sulfate, are the following:

a lot less oxygen is required and thus a lot less energy is needed;

the process is much faster.

is less biological slurry;

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There is a method of processing water containing sulfur compounds by oxidation of sulfur-containing wastewater, in particular sulphides, in aerobic conditions to elemental sulfur with subsequent oxidation to sulfates.

This method is carried out using bacteria species such as Thiothrix and Beggiatoa in the manufacturing plants. These filamentous bacteria impede effective protection of the pulp, causing the washing of the pulp (decrease volume). This phenomenon has two undesirable consequences: a reduction in the activity of installation of wastewater, leading to reduced cleaning performance, and increase taxes as a result of the increased loading of compounds with high chemical oxygen demand due to the washed pulp.

The presence of high amounts of other sulfur compounds, for example, when the sulfur content of more than 350 to 500 mg/l or when the sulfur content in relation to the chemical requirements of wastewater oxygen demand (COD/S) less than 10 in the wastewater also causes difficulties in anaerobic wastewater treatment, because the formed sulfide inhibits bacteria that produce methane. At the same time, anaerobic wastewater treatment in General has the advantage compared to , is there a huge need in the process, allowing anaerobic purification of organic wastewater, even when these effluents contain high amounts of compounds of measures.

It was found that the selection of an unusually high concentration of sulfide per unit amount of biomass achieve high production efficiency of sulfur.

In the first aspect of the invention the method is characterized by the fact that the reactor is used to download pulp of at least 10 mg of sulfide per mg of nitrogen present in the pulp in an hour, download pulp is calculated by oxidizing the sulfide portion of the biomass.

The following aspect of the invention the method is characterized in that when the processing of sulphide-containing water in the presence of organic contaminants, the amount of sulfide entering the reactor per day, is at least 10 g per 1 m2the surface of the biomass.

In yet another aspect, the method is performed in two stages, the first stage involving the oxidation of at least part of the sulphide to elemental sulphur in the first aerobic reactor, using a minimum of sulfide loading, and the second stage comprising the further oxidation in the second aerobic reactor to sulfate.

In other the sulfur compounds first anaerobically reduced to sulfide, and thus the resulting sulfide is then oxidized in the aerobic reactor, using a minimum of sulfide loading in the aerobic reactor.

Minimum sulfide loading, which is required in the process according to the invention preferably is expressed as loading sulfide pulp, i.e., the amount of sulfide that is present in the aerobic reactor per unit time with respect to the mass of the bacterial slurry, which oxidizes sulfide. Download pulp is at least 10 mg S mg N per hour. Here the number of bacteria (biomass) is determined based on the nitrogen content in it. It is established that loading sulfide slurry is less than 10 mg S/mg N h leads almost exclusively to the formation of sulfate, which is not desirable because the sulfate cannot be properly separated from the recycled flowing stream, while elemental sulfur, which is formed at higher loads the pulp can be separated easily. Preferably, when used as a loading slurry of at least 20 mg S/mg N hour, and even more preferably at least 30 mg S/mg N hour. Download pulp about 35 mg S/mg N hour and more evident in the result, the program assumes that what sulfide includes all organic, ionic and non-ionic compounds of divalent sulfur, such as sulfide (S-2), hydrosulfide (HS-), hydrogen sulfide (H2) and the corresponding polysulfide substances.

It is suggested that under wastewater indicated any liquid water-based, containing at least one component, such as a sulfur compound, which must be extracted from it.

The pulp used in the aerobic reactor, contains oxidizing sulfur bacteria, such as species of Thiobacillus and Thiomicrospira.

Download pulp, which should be used in this process can be achieved by selecting the appropriate retention time of wastewater in the aerobic reactor or other parameters such as the number of the pulp in the reactor, the concentration of sulfide in the wastewater or oxygen concentration.

Found that the oxygen concentration is not critical in the process of the present invention. It can cover a very wide limits and preferably will be within 0.1 9.0 mg O2even more preferably about 4 mg O2per liter of material in the reactor.

Download pulp according to the BL. 1. In conventional processes download pulp below 0.1 mg S/mg N hour.

In table 1 the number of the pulp (biomass) is expressed as the nitrogen content in bacteria. In order to calculate the dry matter content of this expression, this number should be multiplied by a factor of 8.3. It is evident from table 1 that gives the option to convert the entire contents of the sulfide to sulfur by using a load of pulp above 35 mg S/mg N hour.

The process of this invention preferably is performed in such a way that the reactor uses biomass, which is in the form of biofilms, which are associated with a support material. Suitable carrier materials include any polymer or other material known for this purpose, such as polyurethane, polyethylene, polypropylene, PVC skin, etc.

Preferably, when the process produces elemental sulfur as the only or almost the only sulfur product. This product may be separated from the resulting aqueous stream by filtration, centrifugation, sedimentation etc., in order to avoid getting stronger oxidized sulfur compounds, the concentration of sulfide in the exit stream of the reactor, the production is, when this concentration is in the range of 0.5 to 30 mg S2-per liter of the resulting stream.

The values shown in table 1, only applies to wastewater flows, which do not contain organic matter. When organic matter is present in the wastewater, will grow more biomass, which does not oxidize the sulfide, resulting in the fact that the nitrogen content of the total biomass is higher in content-based table 1. In the case where the organic matter present in the wastewater, as a defining parameter for the degree of conversion of sulfide to elemental sulfur can be used for surface loading sulfide (where it is understood that the surface is the surface of the biofilm). Values for this parameter are listed in table 2.

Thus, the process according to this invention preferably is performed at surface loading sulfide at least 10g S/m2day, and even more preferably between 20 and 25 g S/m2day. When no organic matter is present, can be used the values given in table 1.

It was found that in the process of this invention has a pH in aerobic re acetelyne below 5, since it is known that oxidizing sulfur bacteria grow when the pH is lower than 0.5.

Minimum load sulfide and reactor required to achieve efficient conversion of sulfide, can also be used in the two-stage process in which: (a) at least part of the sulphide is oxidized to elemental sulfur in the first aerobic reactor;

b) the liquid obtained in step (a) that contains elemental sulfur and possibly sulfide and other ingredients, served in the second aerobic reactor, in which sulfur and sulfide are oxidized to sulfate. Phase separation can be placed between the stages (a) and (b) in order to extract the main part of the sulphur in the elemental form.

This manifests itself as an exceptional advantage when treated water is the water, which under normal conditions of processing would lead to undesirable growth of filamentous bacteria species such as Thiothrix and Beggiatoa. This may be the case with water containing relatively high amounts of organic contaminants in addition to sulfide. Minimum load sulfide can be expressed as the minimum number of sulfide per unit weight of biomass per hour, as determined above. It can also be virture per hour. In this case, the minimum load sulfide is 25 mg S/LCAS.

It is unexpected that the increase in load sulfide in the first aerobic reactor, i.e. an increase in the concentration of sulfide, reducing processing time and/or decrease revised volume would improve the efficiency and the extraction of sulfur and secondary aerobic treatment of other pollutants. In particular, the present process allows for improved retention of the pulp in the second stage aerobic treatment. This is shown in table 3, which shows the test results obtained using the reactor described in the patent application of the Netherlands N 8801009 (for the conversion of sulfide to sulfur).

The impact of changes in process parameters on the efficiency of extraction of sulfide and the growth of filamentous bacteria is shown in table 4.

From table 4 it follows that the only time the hydraulic retention and concentration of sulfide in the wastewater do not determine directly the performance of the primary aerobic treatment. On the contrary, a significant growth of undesirable filamentous bacteria that oxidize sulfur occurs when loading sulfide less than about 20 mg S2-LCAS.

The oxidation of sulfide in the two-stage process can be the result of elemental sulfur and/or sulfate depending on retention time and oxygen concentration. In most cases, is the predominant oxidation to sulfur, since the latter can be removed more conveniently by sedimentation, centrifugation, floculating or filtering. For this purpose a limited amount of oxygen. The sulfide is oxidized in the first aerobic reactor of relatively small size and having a high flow rate (retention time of from several tens minutes to several hours), and other oxidizable components are then extracted in the aerobic reactor of relatively large size and having a long retention time (for example 24 hours).

Device for separating elemental sulfur can be placed between the two reactor the den from sulfur compounds.

The process according to the invention can also be used for anaerobic treatment of wastewater, even if they contain very high amounts of sulfur compounds, whereby they are released from sulfur compounds in a high degree. Sulfur compounds are reduced to sulfide in anaerobic reactor, and the sulfide is then removed by oxidation to elemental sulfur, as described above. When the concentration of sulfur compounds in the water that must be processed is very high, part of the purified water is preferably recycled to the water to be purified. Preferably, when the ratio of recycled ratio between the amount of water that is recycled to the anaerobic reactor, and the amount of purified water, which is reset) is generated so as to maintain the sulfur content in the anaerobic reactor below 800 mg/S/l, more preferably below 500 mg S/l, and even more preferably below 350 mg S/L.

The process can be used for processing waste streams containing different sulfur compounds in almost any concentration. Sulfur compounds can be inorganic compounds such as sulfate, sulfite, thiosulfate, tetrathionate, elementid, diallylsulfide, mercaptans, sulfones, sulfoxidov, sulfonic acids and the like. The process is particularly suitable for processing water containing sulphates, sulphites and thiosulfate.

Suitable bacteria for recovery of sulfur compounds to sulfide include, mainly bacteria, reducing sulfur and sulfate, such groups of species, as Desulfovibrio, Desulfotomaculum, Desulfomonas, Desulfobulbus, Desulfobacter, Desulfococcus, Desulfonema, Desulfosarcina, Desulfobacterium and Desulforomas.

In General, these bacteria are available from various anaerobic cultures, and/or they grow spontaneously in anaerobic reactors.

As a result of a partial recirculatory purified flowing stream in flowing water, the concentration of sulfide in anaerobic digestion is reduced in such a way that anaerobic flora (mainly bacteria that produce methane) is not inhibited.

Another advantage of this invention lies in the fact that there is no need to decrease the pH of the partially treated wastewater in order to allow the extraction of sulfide, additionally, there is no need for gas scrubbers, which in turn produce secondary effluent.

By selecting the appropriate krutosti recirculatory may vary within wide limits and can be, for example, 1 10. When the processed waste waters have a high sulfur loading, recycle a relatively large portion of purified water. Thus, the waste water containing, for example, 30 g/l of a substance with high COD and 2 g/l of sulfur compounds (calculated as sulfur) that can be effectively processed by the process according to this invention.

The device is suitable for performing a cleaning process includes a reactor anaerobic digestion associated with the reactor for the oxidation of sulfide to elemental sulfur, and a separator for separating elemental sulfur, and then the pipeline to supply part of the discharge flow separator in the anaerobic reactor.

Process for removal of sulfur compounds can be performed, for example, in processing plants, as schematically shown in Fig. 1, according to which the wastewater stream 1 is fed into an anaerobic reactor 2, in which organic pollutants are converted mainly to methane and sulfur compounds are converted to the sulfide. Educated gases are removed from the anaerobic reactor 2 through a pipeline (not shown). The anaerobic reactor is connected through a pipe 3 with an oxidizing reactor 4, where the obtained sulfide into elemental sulfur is of necessarily leads to sulfur. Oxygen is introduced through the inlet 5 with the corresponding flow rate. The reactor contains optional media for oxidizing sulfur bacteria. Retention time in the reactor 4 is relatively short (e.g. less than 20 minutes). The pipe 6 enters the water, which is already recycled in the reactor 4, the separator 7, where the sulfur is separated through the outlet 8. Recycled wastewater is then divided into a finite stream 10 and the recirculated stream 11, the ratio between the flow is regulated at the input 1 in accordance with the characteristics of the effluent to be processed.

In the process according to this invention, in order to remove heavy metal ions from water, which also contains compounds of sulfur, water artificially introduced sulfide ions, which react with metal ions to form sulfides of metals, and the remaining sulfide is oxidized to elemental sulfur in the aerobic reactor, using a minimum load sulfide as described above.

Sulfide ions, which are necessary to obtain the sulphides of the metals, may be added to the flow at the inlet of the reactor. Mainly, sulfide ions are obtained in water by anaerobic recovery of sulfur compounds, which mogue sulfur should be added, it is preferable to elemental sulfur.

Preferably, when the anaerobic stage is to use the ratio of sulfur/metal, which is sufficient to ensure almost complete precipitation of heavy metals. Thus, all ions of heavy metals are trapped sulfide in anaerobic stage.

Preferably, sulfides of metals and elemental sulfur formed during the cleaning process, separated together, for example by sedimentation, filtration, centrifugation or flotation.

It may be desirable to add a nutrient medium (electron donor) in order to recover the sulfur compounds to sulfide. Processing of water that does not contain organic impurities, the addition of such an electron donor is required. Depending on the particular use may be added the following nutrient medium: hydrogen, carbon monoxide and organic compounds such as formic acid, sugar, fatty acids, alcohols and starch. If necessary, can also be added nutrients, in the form of nitrogen, phosphorus and trace elements.

The example of wastewater containing heavy metals, which can pererabotki wastewater for example, in the photographic industry and metallurgy, and the drains of the scrubbers for exhaust gases. Heavy metals that can be removed using the process of this invention include all metals, with poorly soluble product of the corresponding sulfide. Their examples are lead, tin, bismuth, cadmium, mercury, silver, zinc, copper, Nickel, cobalt, iron, manganese, chromium, vanadium and titanium.

The retention time of the sulfides of the metals in the aerobic stage should be much shorter in order to prevent excessive oxidation, when the oxidation of sulfide is carried out to complete, sulfides of metals cannot be stored in the form of sediment.

By maintaining a low residual concentration of sulfide in the aerobic stage (micro-aerofiles oxidation of sulfide) and at the stage of separation, where elemental sulfur and high biomass is separated from the flow of water, prevented the re-dissolution of metals. This concentration may vary within very wide limits and can be, for example, 0.1 to 50 mg/l, preferably 1-10 mg sulfide/L. Maintaining the required concentration of sulfide may, for example, be monitored by measuring the concentration of sulfide or oxidation-fossilien to be preferably, the negative during the oxidation of sulfide and separation, for example, below 100 MB. It is noted that the redox potential during the first stage, i.e., anaerobic recovering sulphur, should generally be set in the range from -200 to -400 mV.

Any sulfide ions remaining after phase separation, can be oxidized, such as sulfide, by any known method (for example by aeration or adding peroxide) to drop.

Process for removal of heavy metals according to this invention may, for example, be performed in the device, which is schematically depicted in the accompanying Fig 2. According Fig.2 wastewater stream that must be recycled (flowing), 1 is the buffer /mixing tank 12. The nutrient medium and the electron donor may be added through the inlet 13. The liquid is removed from the buffer tank through the inlet 14 and is filed under anaerobic reactor 2 where sulfur compounds are reduced to sulfide and sulfides are formed of metals. Sulfides of metals down to the bottom of reactor 2 (not shown). Gases obtained during the anaerobic process, discharged through the pipe 15 to the gas apt the reactor 2, is discharged through pipes 3 in the aerobic reactor 4, where the oxidation of sulfide to elemental sulfur. Air is introduced into the aerobic reactor 4 through the inlet 5. The gas is discharged through the pipe 17 into the apparatus for removing odor 18.

Fluid that contains sulfur is removed from the aerobic reactor 4 through the outlet 6 and is fed to the separator 7 for separating sulfur. Sulfur is separated through the exit 8, and while the purified effluent stream leaves the separating apparatus 7 through the outlet 10.

The measurement results related to the processing system operating according to the process of this invention are summarized in tables 5 and 6 below. a after anaerobic stage b after aerobic stage.

Example. In order to assess the balance between the production of sulfur and/or sulfate and consumable utilization sulfide slurry in the extraction of sulphide, sulphur was measured in a large number of stationary situations.

In this experiment, the reactor was fed only sulphide and nutrient medium, but not organic compounds, so that the N content was determined only oxidizing the sulfide biomass.

The results are shown in Fig.3. Below 10 mg S/mg N. what="ptx2">

The content of nitrogen in bacteria, oxidizing the sulfur was measured using a modified Kjeldahl method, developed Novozomsky et.al. (1983) Comm. soil Science Plant. Aual. 14.239-249.

1. A method of processing water containing sulfur compounds, including biochemical oxidation of sulfide to elemental sulfur in the aerobic reactor in the presence of oxygen and biomass in the form of sulfidogenic bacteria, discharge of treated water, characterized in that in the processing of sulfide-bearing water quantity sulfide entering the reactor per unit time, the nitrogen content in the biomass comprises at least 10 mg of sulfide per mg of nitrogen per hour.

2. The method according to p. 1, characterized in that the amount of sulfide entering the reactor is at least 20 mg of sulfide per mg of nitrogen per hour.

3. The method according to p. 1, characterized in that the amount of sulfide entering the reactor is at least 35 mg of sulfide per mg of nitrogen per hour.

4. A method of processing water containing sulfur compounds, including biochemical oxidation of sulfide to elemental sulfur in the aerobic reactor in the presence of oxygen and biomass in the form of sulfidogenic bacteria, discharge of treated water, characterized in that when PE in the reactor per day, is at least 10 g per 1 m2the surface of the biomass.

5. The method according to PP. 1 to 4, characterized in that the oxygen concentration in the aerobic reactor regulate within 0.1 9.0 mg/l, preferably 4 mg/l

6. The method according to PP. 1 to 5, characterized in that the biomass in the aerobic reactor is present as biofilms attached to the polymer carrier.

7. The method according to PP. 1 to 6, characterized in that the concentration of sulfide in going after the reactor the flow of water maintained within the range of 0.5 to 30 mg/l

8. A method of processing water containing sulfur compounds, including biochemical oxidation of sulfide to elemental sulfur in the aerobic reactor in the presence of oxygen and biomass in the form of sulfidogenic bacteria, discharge of treated water, wherein the processing sulfacetamide water in the presence of organic impurities in a high concentration to prevent growth of filamentous bacteria type Thiothrix and Beggiatoa, the number of sulfide entering the aerobic reactor for oxidation is at least 25 mg of sulfide on 1 l of the content in the reactor per hour, with at least a portion of the sulfide is oxidized to sulfur, and formed in the reactor liquid after the CTD is different, however, the amount of sulfide is at least 50 mg of sulfide on 1 l of biomass per hour.

10. The method according to p. 8, characterized in that the amount of sulfide is 100 to 1000 mg of sulfide on 1 l of biomass per hour.

11. A method of processing water containing sulfur compounds, including biochemical oxidation of sulfide to elemental sulfur in the aerobic reactor in the presence of oxygen and biomass in the form of sulfidogenic bacteria, discharge of treated water, characterized in that in the processing of water containing or sulfate, or sulfite, or thiosulfate, or a mixture thereof, or tetrathionate, or elemental sulfur or organic compounds of sulphur, water previously subjected to anaerobic treatment in the presence of sulfur - and sulfate-reducing bacteria to the recovery of sulphur compounds to sulphide with subsequent oxidation of the sulfide in one of the paragraphs. 1 10.

12. The method according to p. 11, wherein the anaerobic treatment is carried out at maintaining the content of sulfur compounds (in terms of elemental sulfur) below 800 mg/l, preferably below 350 mg/l

13. The method according to PP. 11 and 12, characterized in that the content of sulfur compounds during anaerobic treatment support through recycling caramanna the presence in water of heavy metal ions on stage anaerobic treatment of water content of sulfur compounds in terms of elemental sulfur to a concentration of heavy metal ions support required for complete precipitation of heavy metal ions in the form of sulphides, their subsequent oxidation are at the stage aerobic treatment of one of the PP. 1 10.

15. The method according to p. 14, characterized in that on the stage aerobic treatment support the redox potential of the system below 100 mV.

16. The method according to p. 14, characterized in that on the stage aerobic treatment of the concentration of sulfide ions support of 0.1 to 50 mg/l, preferably 1 to 10 mg/L.

 

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1 dwg

FIELD: mechanics; chemistry.

SUBSTANCE: completely-block modular clearing station includes tanks of multistage biological sewage treatment by communities attached on a filamentary brush mounting attachment and free-floating microorganisms of active silt, desilting devices and sludge thickeners, the devices dehydrating deposits of sewage and communications for a supply and a tap of sewage, feedings of air, a tap of collecting deposits. The clearing station is executed in the form of, at least, four-storeyed building of tower type with the isolated arrangement of bioreactors. The station is supplied with air ejectors, placed on a ground floor and communicated through air intake channels with the ventilating chamber passing from top to bottom through all floors of clearing station and arranged floor-by-floor with ventilation ducts. The station also is arranged by the ventilators assigning damp air, completed in bioreactors for limits of a building of clearing station through clearing and disinfecting devices, supplied by biopunchers for processing of the dehydrated deposits of sewage, ripening and drying at the expense of warm air heated in the air ejectors.

EFFECT: lowering of specific expenditures of the electric power on unit of cleared sewage, improvement of hygienic working conditions of serving staff and abbreviation of the area of the earth assigned under clearing station.

4 dwg

FIELD: sewage treatment facilities.

SUBSTANCE: invention is related to the field of biological purification of sewage from organic compounds, nitrogen and phosphorus. To realise the method, the following hydraulically communicated stages - anaerobic, anoxic, aerobic - are performed for treatment with activated sludge with membrane separation, stage of deaeration that precedes stage of anaerobic treatment, stage of powdered activated carbon (PAC) treatment with membrane separation. Method also includes recirculation of sludge mixture from the aerobic treatment stage to stage of deaeration and recirculation of sludge mixture from anoxic stage to anaerobic stage. Purified water after serial anaerobic stage at load on activated sludge by "БПК" of 2.0-4.0 mg/g·hr and anoxic stage at load on activated sludge by nitrogen of 3.5-4.5 mg/g·hr, "БПК" of 8-13 mg/g·hr is supplied directly to the stage of aerobic treatment with membrane separation. At that load on activated sludge by nitrogen makes 0.8-1.2 mg/g-hr, by oil products - 0.5-0.7 mg/g·hr, according to synthetic surfactants - 0.16-0.22 mg/g·hr and by phenols - 0.18-0.25 mg/g·hr. At the stage of anoxic treatment 80-90% of recirculated sludge mixture is supplied from deaeration stage. Water purification with PAC is carried out at concentration of dissolved oxygen to 4.0 mg/l due to supply of compressed air and PAC concentration of 20-30 g/l at its single charging. At that load on PAC by oil products makes 0.35-0.45 mg/g·hr, by synthetic surfactants - 0.06-0.07 mg/g·hr and by phenols - 0.02-0.024 mg/g·hr.

EFFECT: method provides for increased degree of purification from nitrogen and phosphorus, wider range of removed organic compounds, process simplification and reduction of its duration.

2 tbl, 3 ex

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