RU2440306C1 - Method of providing reliable purification of waste water from nitrogen and phosphorus compounds - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: method involves successively holding a biocenosis of microorganisms which remove organic and mineral impurities from waste water in anaerobic, anoxic and aerobic conditions. The following operations are carried out: the rate of return of active sludge from secondary settling tanks and the flow rate of the circular stream of the sludge mixture into a denitrifier from the outlet of a nitrifier is measured; the range of possible rates of removal of excess sludge is divided by a finite number of intervals and in the load on the sludge is calculated in each; graphs of concentration of impurities in the purified water on control ingredients versus the load on the sludge are plotted; the plotted graphs are used to search for the range of the working load on the sludge where the required degree of purification of water on all control ingredients is achieved; biological removal of nitrogen and phosphorus from the waste water in the range of the defined working loads on the sludge is carried out.

EFFECT: improved biological method for purification from nitrogen and phosphorus compounds, high reliability of the purification process, shorter duration of building waste water treatment facilities.

6 cl, 3 dwg, 3 tbl

Description

The invention relates to methods for biological treatment of household and industrial wastewater close to them and can be used in municipal services of cities, towns and industrial enterprises in wastewater treatment from organic pollution, nitrogen and phosphorus.

A known method of biological wastewater treatment, which includes mechanical wastewater treatment in the primary sump, after which the wastewater is fed into a bioactivator with microflora, in which the presence of zones with a heterogeneous oxygen content by means of controlled oxygen input is maintained, and then a mixture of wastewater with active sludge enters the secondary sump for separation into purified wastewater and activated sludge, which is constantly returned to the beginning of the bioactivator. The crude sludge after the primary sump is recycled to the input of the primary sump to create the conditions for the hydrolysis process and the heteroacetogenic process directly in the primary sump. In the secondary sump, zones with a heterogeneous oxygen content are created by adjusting the rate of active sludge recirculation from the secondary sump to the bioactivator inlet (see RF patent No. 2296110, IPC C02F 3/30).

The disadvantage of this method is the narrow scope, because not at all stations there is the possibility of a device for continuously regulating the rate of recirculation of activated sludge from the secondary sump to the bioactivator input. The latter is explained by the fact that, as a rule, activated sludge is removed from the secondary settling tanks according to the technological scheme, which provides for its gravity (under hydrostatic pressure) flow from the bottom parts of the secondary settling tanks to the collection tank, from where activated sludge is recirculated by adjustable pumping units. Since the lengths of gravity lines from the secondary settling tanks to the collection tank are different, a continuous change in the performance of the regulated pumping units will not lead to uniform sampling of activated sludge from the secondary settling tanks.

The closest analogue to the present invention is a method for the biological removal of phosphorus from wastewater. It includes the sequential maintenance of a community of microorganisms that purify wastewater from organic and mineral impurities in anaerobic, anoxic and aerobic conditions in capacitive structures with intensive mass transfer, created using, respectively, mixers, pumps and sparge air. Return activated sludge from the secondary settling tanks is mixed with a stream of initial wastewater that has passed through grates and sand traps, the mixture is subjected to flotation treatment, after which the flotation concentrate is kept for at least half an hour in anaerobic bioreactors with continuous stirring, and the clarified liquid with sludge water is fed into the denitrifier along with the sludge mixture’s circulation flow from the outlet of the nitrifier and the anaerobically treated flotation concentrate, then the sludge mixture from the denitrifier is sent to the nitrifier, where gayut stirring by bubbling air, with the grow aerobically nitrifying activated sludge biomass is subjected to flotation processing to flotators, flotation concentrate excess activated sludge is dewatered to a cake and subjected biocomposting under aerobic conditions without loss of phosphorus in the mixture of sawdust to produce enriched vermicompost phosphorus.

The disadvantages of this method is the following.

1. Low technological reliability indicators, since the method does not provide for the possibility of regulating the degree of water purification by nitrogen and phosphorus. The latter is explained by the fact that high degrees of water purification according to these indicators are not always compatible within the framework of one technology. For example, when changing (up to certain limits) the volumes of removal of excess activated sludge of biomass nitrificator of biomass grown under aerobic conditions, the degree of water purification by nitrogen and phosphorus changes in opposite directions - one increases and the other decreases.

2. A narrow scope, because it is designed for the preferential removal of only phosphorus from wastewater to the detriment of the efficiency of the removal of another nutrient - nitrogen. The latter is explained by the fact that water is supplied to the denitrifier zone after flotation treatment, i.e. with residual dissolved oxygen, which will inhibit the denitrification process.

The objective of the present invention is to improve the above method in order to improve technological parameters of reliability and expand the scope.

The problem is solved in that in the known method, which includes sequentially maintaining a community of microorganisms that purify wastewater from organic and mineral impurities, under anaerobic, anoxic and aerobic conditions in capacitive structures with intensive mass transfer created by means of stirrers and sparging with air, the return of active sludge from secondary sumps, feeding into the denitrifier (anoxic conditions) a circulating stream of sludge mixture from the outlet of the nitrifying agent (aerobic conditions), removal and processing adherent aerobically nitrifying activated sludge biomass, in accordance with the present invention during operation the following operations:

a) record at least the flow rate Qvi, i of the return of activated sludge from the secondary sumps and the flow rate Qci, i of the circulation flow of the sludge mixture into the denitrifier from the output of the nitrifier, where i is the number of the fixation mode, i = 1, 2, 3, ..., n1, where n1 is any number;

b) break down the range of possible costs of Qi removal to treat the excess activated sludge biomass nitrificator of biomass grown under aerobic conditions into n2 intervals, where n2 = 3, 4, 5 ..., n2, where n2 is any number;

c) in the current fixation mode i, they will test the modes of biological removal of nitrogen and phosphorus from wastewater at one point of each of the n2 intervals of possible flow rates Qii, determine the daily flow rate of wastewater Qi, j entering the treatment, the concentration C of _BOD i, j of pollution in the initial water according to the biochemical oxygen demand, the concentration of contaminants in the purified water according to the controlled ingredients Ck, i, j, the average concentration of sludge in capacitive i structures Xi, j, where j = 1, 2, 3 ..., n2, k = 1, 2, 3 ..., n3, where n3 is the number of controlled ingredients;

d) in the current fixation mode i, at the tested points of each of the n2 intervals of possible costs Qi, the load on silt N _{BPKi, j} = Qi, j * C _{BPKi, j} / (V * Xi, j) is calculated, where V is the volume of capacitive structures;

e) in the current fixation mode i, in the same coordinate axes, plots of the dependences of the concentration of contaminants in the purified water are plotted against the controlled ingredients Ck, i, j on the load on sludge N _{BPKi, j} ;

e) the dependencies constructed at stage d) search for the range of the working load for sludge from N _BOD , _min to N _BOD , _max , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp. Moreover, if this range is not found, then at least the flow rate of activated sludge return from the secondary settling tanks at a new level Qvi, i + 1 and / or the flow rate into the denitrifier of the circulation flow of the sludge mixture from the nitrification outlet at a new level Qci are changed and fixed , i + 1, the sequence of operations (b) through (f) is repeated until the range of the working load for sludge from N _BOD , _min to N _BOD , _max , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp, or apply additional purification systems according to ingre m diants for which the range of the working load for sludge, providing the required degree of purification for the specified ingredients, is not found or is outside the range of the working load for sludge from N _BOD , _min1 to N _BOD , _max1 , at which the required degree of water purification is achieved for most controlled ingredients, where m∈1, 2, 3 ..., n3;

g) in the future, biological removal of nitrogen and phosphorus from wastewater is carried out in the range of sludge working loads from N _BOD , _min to N _BOD , _max or from N _BOD , _min1 to N _BOD , _maxl .

A development option is possible when the study of various modes of biological removal of nitrogen and phosphorus from wastewater is carried out on a computer model.

A development option is possible when the concentration of C _NH4 contaminants in purified water for ammonium nitrogen, for nitrates of C _NO3 , for phosphates of C _PO4 are taken as controlled concentrations of contaminants.

A development option is possible when the concentration of pollutants in treated water is taken as controlled concentration of total nitrogen C _Ntotal, total phosphorus C _Ptot .

A development option is possible when, at step e), a range of sludge workload is searched from N _BOD , _min to N _BOD , _max , at which the following degree of water purification Ck, mp / Kz is achieved for all controlled ingredients, where Kz is the technological reserve coefficient , Kz> 1.

A development option is possible when, as additional purification systems for phosphates C _PO4 and total phosphorus C _Ptot , treatment with chemical reagents is accepted.

Distinctive features of the proposed method is the following.

1. The fixation during operation of at least the flow rate Qvi, i of the return of activated sludge from the secondary sumps and the flow rate Qci, i of the circulation flow of the sludge mixture into the denitrifier from the output of the nitrifier, where i is the number of the fixing mode, i = 1, 2, 3 , ..., n1, where n1 is any number (known).

2. A breakdown of the range of possible costs of Qi removal for the treatment of excess activated sludge biomass nitrificator of biomass grown in aerobic conditions into n2 intervals, where n2 is any number (not known).

3. Setting the number of intervals n2 = 3, 4, 5 ..., n2, where n2 is any number (not known).

4. Testing of the regimes of biological removal of nitrogen and phosphorus from wastewater at one point of each of the n2 intervals of possible costs Qii (not known).

5. Determination at one point of each of the n2 intervals of possible flow rates Qii of the wastewater flow rate Qi, j for treatment, the concentration C of _BOD i, j of contaminants in the source water according to the biochemical oxygen demand, the concentration of contaminants in the purified water according to the controlled ingredients Ck, i, j, the average concentration of sludge in capacitive i structures Xi, j, where j = 1, 2, 3 ..., n2, k = 1, 2, 3 ..., n3, where n3 is the number of controlled ingredients (not known).

6. Calculation in the current fixation mode i at the tested load points on silt N _BOD i, j = Qi, j * С _BOD i, j / (V * Xi, j), where V is the volume of capacitive structures (not known).

7. The construction in the current mode of fixing i in the same coordinate axes of the graphs of the dependences of the concentrations of contaminants in the treated water for the controlled ingredients Ck, i, j on the load on sludge N _BOD i, j (not known).

8. Determination by the constructed dependence of the range of the working load on sludge from N _BOD , _min to N _BOD , _max , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp (not known).

9. Change and fixation of at least the rate of return of activated sludge from the secondary sludge at a new level Qi, i + 1 and / or the flow rate to the denitrifier of the circulating flow of sludge from the nitrification outlet at a new level _Qi , i + 1 (not known )

10. Repeating the sequence of operations (b) to (f) until the range of the sludge load from N _{BPK, min} to N _{BPK, max} , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp, or the range of the load silt from N _BOD , _min1 to N _BOD , _max1 , at which the required degree of water purification is achieved for most controlled ingredients (not known).

11. Biological removal of nitrogen and phosphorus from wastewater at a sludge working load from N _{BOD, min} to N _{BOD, max} or from N _{BOD, min1} to N _{BOD, max1} determined by the constructed dependence (not known).

12. The study on a computer model of the various modes of biological removal of nitrogen and phosphorus from wastewater, differing only in the volumes of removal of excess activated sludge that has grown under aerobic conditions of the nitrification biomass nitrifier (unknown).

13. Acceptance of concentrations of C _NH4 contaminants in purified water as ammonia nitrogen, C _NO3 nitrates, C _PO4 phosphates as controlled concentrations of pollutants (known).

14. Acceptance of concentrations of total nitrogen C _Ntotal and total phosphorus C _Rotch (known) as controlled concentrations of pollution.

15. Search for the range of sludge workload from N _BOD , _min to N _BOD , _max , at which the following degree of water purification Ck, mp, / Kz is achieved for all controlled ingredients, where Kz is the technological reserve coefficient, Kz> 1 (not known )

16. The use of additional purification systems for ingredients m, for which a range of sludge working load providing the required degree of purification for the specified ingredients is not found or is outside the range of sludge working load from N _{BOD, min1} to N _BOD , _max1 , at which the required degree of water purification is achieved for most controlled ingredients (not known).

17. The use of _post -treatment systems for phosphates C _PO4 and total phosphorus C _Pobot chemical treatment systems (known).

According to the information available to the authors, the distinctive features 2-12, 15-16 are not known, and the rest are known. However, their combined use in the claimed method allows to obtain two positive and two new effects.

The first positive effect is that the technological indicators of reliability are increased, since the method provides the ability to control the degree of water purification by nitrogen and phosphorus. The latter is achieved due to the fact that, based on the constructed experimental dependence of the concentrations of pollutants in the treated water according to the indicated indicators, on a complex indicator - load on sludge N _BOD , it becomes possible to determine the range of working load on sludge at which an acceptable compromise is reached between the degree of water purification by nitrogen and phosphorus.

The second positive effect is that the scope of the method is expanding, because it eliminated the preference for increasing the degree of purification of wastewater from phosphorus to the detriment of the efficiency of purification from nitrogen. The latter is achieved by the fact that in the denitrifier zone the oxygen concentration decreases, because water supply to it after flotation treatment is excluded.

The first new effect is that the duration of the commissioning of wastewater treatment plants is reduced since using a computer model it is possible to quickly determine the desired range of sludge workload from N _BPK , _min to N _BPK , _max . The latter is achieved by the fact that, in contrast to real treatment facilities, where after a change in the volume of disposal for processing excess activated sludge, a transitional process lasting up to a week occurs, when using a computer model, the construction of schedules and the determination of the workload for sludge does not require time delays. The indicated new effect is achieved not only due to the presence of the distinguishing feature No. 12, but also to the others, since not all dependencies can be implemented on a computer model. The indicated can.

The second new effect is that the probability indicators of reliability increase, since the method provides a reserve for the degree of water purification, because provides a lower concentration of contaminants in the treated water - Ck, mp, / Kz, where Kz is the technological reserve coefficient.

Thus, the claimed method meets the criterion of "inventive step".

Graphic material illustrating the proposed method is presented in the following figures:

figure 1 is a block diagram of a system in which the method according to the invention can be used;

figure 2, 3 - examples of the dependence of the concentrations of contaminants in purified water on ammonium nitrogen C _NH4 , nitrogen nitrates C _NO3 , phosphates C _PO4 from the load on sludge N _BOD, used in the implementation of the method _.

Figure 1 as an example schematically shows one of the possible technologies for wastewater treatment from organic contaminants, nitrogen and phosphorus compounds. This is the technology at Camptown University. The invention allows the use of other cleaning technologies using capacitive structures with activated sludge. The technological scheme contains capacitive structures 1 in which zone 3 of anaerobic conditions and zone 4 of anoxic conditions (denitrifier) are created using stirrers 2, and zone 6 of aerobic conditions (nitrificator) using air sparging system 5. Wastewater supplied to the treatment plant is supplied to the reservoir facilities 1 through the source water pipe 7, and a mixture of the source water and activated sludge is discharged through the sludge mixture pipe 8 to the secondary settling tanks 9. The purified water is discharged through the purified water pipe 10 for further treatment or discharged into the body of water . The sludge mixture is fed to the denitrifier (anoxic conditions) from the nitrifier outlet (aerobic conditions) through a nitrate recycle line 11, and activated sludge is returned from the secondary sumps 10 through a recycle sludge line 12. The invention also allows the use of other recycle streams, for example recycle sludge into the anoxide zone 3 and the denitrification zone 4 through the pipeline 13 denitrified sludge. Excess activated sludge is removed for processing the biomass nitrificator of biomass grown in aerobic conditions through a pipeline 14 of excess sludge.

In table.2 and 3 presents the quantitative results of the application of the proposed method on the example of treatment facilities, a diagram of which is presented in figure 1.

The method provides for the following operations:

a) fixing at least the flow rate Qvi, i of the return of activated sludge from the secondary sumps through the return sludge pipe 12 and the flow rate Qci, i of the sludge mixture circulation flow to the denitrifier from the nitrification outlet through the nitrate recycle pipe 11;

b) a breakdown of the range of possible costs of Qii removal for the treatment of excess active sludge discharged through aerobic conditions of the biomass nitrifier of biomass grown in the pipeline 14 into n2 intervals, n2 = 3, 4, 5 ..., n2, where n2 is any number;

c) testing in the current i-th mode of fixing the modes of biological removal of nitrogen and phosphorus from wastewater at one point of each of the n2 intervals of possible flow rates Qi with the determination of:

- the daily flow rate of wastewater Qi, j entering the treatment through the source water pipe 7;

- the concentration of _BOD i, j contaminants in the source water according to the biochemical oxygen demand;

- the concentration of contaminants in the treated water (in the pipeline 10 of purified water) for the controlled ingredients Ck, i, j. Depending on the type of water source where the treated wastewater is discharged, either concentrations of C _NH4 contaminants in treated water for ammonia nitrogen, nitrates C _NO3 , phosphates C _PO4 or pollution concentrations for total nitrogen C _Ntot can be taken as controlled concentrations of pollutants _. and total phosphorus C _total ;

- the average concentration of Xi, j silt in capacitive structures 1

(to speed up the process, testing of the regimes of biological removal of nitrogen and phosphorus from wastewater is carried out by computer simulation);

d) calculation in the current i-th fixing mode at the tested points of each of n2 intervals of possible costs Q and load on silt N _BOD i, j = Qi, j / (V * Xi, j);

e) plotting in the current i-th mode of fixation in the same coordinate axes the graphs of the dependences of the concentrations of contaminants in the purified water according to the controlled ingredients Ck, i on the load on sludge N _BOD i, j, see Figs. 2, 3;

f) a search according to the dependences of the range of the working load for sludge from N _BPK , _min to N _BPK , _max , which was built in step e), at which the required degree of water purification is achieved for all controlled ingredients Ck, mp. If this range is not found, then at least the rate of return of activated sludge from the secondary sumps at a new level Qvi, i + 1 and / or the flow rate into the denitrifier of the circulation flow of the sludge from the nitrification outlet at a new level Qci, i + one. After that, the sequence of operations (b) through (e) is repeated until the range of the working load for sludge from N _BOD , _min to N _BOD , _max , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp, is found. If the result is the desired if the range is not found, then determine the range of the working load on the sludge from N _{BOD, min1} to N _BOD , _max1 at which the required degree of water purification is achieved for most of the controlled ingredients Ck, mp. For other ingredients, additional purification systems are used. For example, as additional purification systems for phosphates C _PO4 and total phosphorus C _Total , treatment with chemical reagents is accepted. In addition, to increase the probability indicators of the reliability of wastewater treatment, a reserve is provided for the degree of water purification by providing a lower concentration of contaminants in the treated water - Ck, mp / Kz;

g) further biological removal of nitrogen and phosphorus from wastewater in the range of sludge working loads from N _BOD , _min to N _BOD , _max .

Corresponding to the invention, the method works as follows.

As an example, we consider the operation of treatment facilities according to the technological scheme presented in figure 1 with the parameters presented in table 1.

In accordance with the present invention perform the following operations:

a) fix i = 1:

- flow rate Qvi, 1 return of activated sludge from the secondary sumps at the level of Qvi, 1 = 10000 m ³ / h;

- flow rate Qci, 1 circulation flow of the sludge mixture to the denitrifier from the nitrification outlet at the level of Qci, 1 = 10000 m ³ / h;

b) break down the range of possible costs of Qi removal to treat the excess active sludge discharged through aerobic conditions of the biomass nitrificator of biomass that is discharged through the pipeline 14 of excess sludge into 9 intervals (in accordance with the invention more than 3, since the plots of the dependences of the concentrations of pollution in purified water for controlled ingredients Ck, i from the load on sludge N _BOD i, j are concave or convex). The range of possible costs Qi is determined taking into account the capabilities at each wastewater treatment plant. Its boundaries, as a rule, are determined by the production capacities of systems for the processing of excess sludge. As an example, we determine this range in the range from 26 to 237 m ³ / h;

c) in the current fixation mode i, the modes of biological removal of nitrogen and phosphorus from wastewater will be tested at one point (maximum) of each of the 9 intervals of possible flow rates Qi and determined:

- daily consumption of wastewater Qi, j entering the treatment;

- concentration C _BOD i, j of contaminants in the source water according to the biochemical oxygen demand;

- the concentration of contaminants in the purified water according to the controlled ingredients Ck, i, j (in this case, ammonium nitrogen C _NH4, i, j, nitrogen nitrates C _NO3 , i, j, phosphates C _PO4 , i, j);

- the average concentration of sludge in capacitive structures Xi, j

(the results of this stage are presented in table 2);

d) in the current fixation mode i at the tested points of each of the 9 intervals of possible costs Qii calculate the load on silt N _BOD i, j = Qi, j * C _BOD i, j (V * Xi, j)

(calculation results are entered in the table, see table 2);

d) in the current fixation mode i, in the same coordinate axes, plots of the dependences of the concentration of contaminants in the purified water are plotted against the controlled ingredients Ck, i, j on the load on sludge N _BOD i, j, see figure 2. Here: 1 is a graph of changes in the concentration of nitrogen of nitrates C _NO3 , 1, j; 2 is a graph of the change in the concentration of phosphates C _PO4 , 1, j; 3 is a graph of changes in the concentration of nitrogen of ammonium C _NH4 , 1, j; 4 - permissible concentration of contaminants in purified water on nitrate nitrogen, taking into account the technological reserve coefficient C _NO3 , mp, Kz = C _NO3 , mp / Kz = 8 / 1.1 = 7.27 mg / l; 5 - the same for ammonia nitrogen C _NH4 , mp / Kz = C _NH4 , mp / Kz = 1.2 / 1.1 = 1.09 mg / l; 6 - the same for phosphates C _PO4 , mp, Kz = C _PO4 , mp / Kz = 0.4 / 1.1 = 0.36 mg / l;

e) the dependencies constructed at stage d) search for the range of the working load for sludge from N _{BOD, min} to N _BOD , _max , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp. Figure 2 presents the results of such a search. It can be seen that in the load range for sludge A the required degree of water purification is achieved for nitrogen nitrates C _NO3 , i, j, in range B for ammonia nitrogen C _NH4 , i, j, in range C for phosphates C _PO4 , i , j. Moreover, the three indicated ranges do not have a common intersection, i.e. for i = 1, there is no solution. For this reason, for example, they change and fix, the flow rate into the denitrifier of the circulation flow of the sludge mixture from the nitrification outlet at a new level Qci, 2 = 14000 m ³ / h, the sequence of operations (b) to (e) is repeated until the range of the working load for sludge from N _BOD , _min to N _BOD , _max , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp. The results of step c) are presented in Table 3, and step e) in FIG. 3. Figure 3 shows that in the load range for sludge D, the required degree of water purification is achieved for all controlled ingredients Ck, mp. Therefore, in the future, biological removal of nitrogen and phosphorus from wastewater is carried out in the range of sludge working loads from N _{BOD, min} to N _{BOD, max} .

From figure 3 it is seen that with an increase in the coefficient of technological stock Kz, wastewater costs, etc. options are possible when, despite the measures applied, the three indicated ranges will not have a common intersection, i.e. the situation presented in FIG. 2 will take place. Then, the working load range for sludge E is determined from N _{BOD, min1} to N _{BOD, max1} at which the required degree of water purification is achieved for most controlled ingredients (ammonium nitrogen C _NH4 , nitrate nitrogen C _NO3 ), and to provide the required degree of purification for phosphates C _PO4 accept treatment with chemicals. In this case, the invention allows their dosing to anywhere in the capacitive structures and beyond.

Table 1 No. p / p Parameter Name Parameter value one The average daily consumption of wastewater Qi, j entering the treatment, m ³ / day 240000 2 The average concentration of contaminants in the source water, mg / l:
by biochemical oxygen demand With _BOD i, j 140 by ammonium nitrogen C _NH4 twenty nitrogen nitrate C _NO3 0.6 phosphate C _PO4 2,4 3 Volume V of tank facilities, m ³ ,
including: 80740 anaerobic zone 16183 anoxide zone 24077 aerobic zone 40523 four Denitrified sludge consumption, m ³ / h 6973 5 Consumption Qvi, i return of activated sludge from secondary sumps, m ³ / h Variable fixed in step a) 6 The flow rate Qi, i of the circulation flow of the sludge mixture into the denitrifier from the outlet of the nitrifier, m ³ / h Variable fixed in step a) 7 The consumption of Qi removal for the processing of excess active biomass nitrifier grown in aerobic conditions, m ³ / h Variable, in the range of 26.3 to 236.8 8 The required concentration of contaminants in purified water, mg / l: by ammonium nitrogen C _NH4 1,2 nitrogen nitrate C _NO3 8 phosphate C _PO4 0.4 9 The coefficient of technological stock, Kz 1,1

table 2 j Q _{1, j,} m ³ / day C _{BOD 1, j} , mg / l Qii, m ³ / h C _NO3 , _{1, j,} mg / l C _NH4 , _{1, j} mg / L C _PO4 , _{1, j,} mg / l X _{1, j,} g / l N _BOD , _{1, j} , g BOD / (g silt day) one 240000 115 26 8.86 0,07 1,5 5.56 0,061 2 241000 110 53 8.56 0,07 0.6 3.94 0,083 3 239000 118 79 8.24 0.09 0.2 3.35 0.104 four 240500 115 105 7.82 0.12 0.1 2.76 0.124 5 238500 120 132 7.45 0.18 0.5 2.47 0.143 6 240000 115 158 7.22 0.32 1,2 2.08 0.164 7 241100 117 184 7.03 0.6 1,6 1.91 0.183 8 240050 113 211 6.81 1,03 1.8 1.68 0,200 9 240070 116 237 6.51 1.7 1.9 1,61 0.214

Table 3 j Q _{2, j,} m ³ / day C _{BOD 2, j} ,
mg / l Qii, m ³ / h C _NO3 , _{2, j,} mg / l C _NH4 , _{2, j} mg / L C _PO4 , _{2, j,} mg / L X _{2, j,} g / l N _BOD , _{2, j} , g BOD / (g silt day) one 238000 115 26 8.36 0,07 1,6 5.43 0,062 2 241500 111 53 8.09 0,07 0.7 3.94 0,084 3 239100 114 79 7.78 0.09 0.3 3.21 0.105 four 240600 116 105 7.31 0.14 0.2 2.77 0.125 5 239500 122 132 6.78 0.23 0.6 2,52 0.143 6 240100 116 158 6.42 0.41 1,2 2.10 0.164 7 242100 118 184 6.2 0.75 1,6 1.92 0.184 8 240080 112 211 5.98 1.22 1.8 1.66 0,200 9 241060 115 237 5.7 1.92 1.9 1,58 0.217

Claims (6)

1. A method for ensuring the reliability of wastewater treatment from nitrogen and phosphorus compounds, including sequentially maintaining a community of microorganisms that treat wastewater from organic and mineral impurities, under anaerobic, anoxic and aerobic conditions in capacitive structures with intensive mass transfer, created by means of mixers and sparging, respectively by air, return of activated sludge from secondary settling tanks, feeding into the denitrifier (anoxic conditions) a circulating stream of sludge mixture from the outlet of the nitrifier (aero bnye conditions), deletion processing adherent aerobically nitrifying activated sludge biomass, characterized in that during operation the following operations:
a) record at least the flow rate Qvi, i of the return of activated sludge from the secondary sumps and the flow rate Qci, i of the circulation flow of the sludge mixture into the denitrifier from the output of the nitrifier, where i is the number of the fixation mode, i = 1, 2, 3, ..., n1, where n1 is any number;
b) break down the range of possible costs of Qi removal to treat the excess activated sludge biomass nitrificator of biomass grown in aerobic conditions into n2 intervals, n2 = 3, 4, 5 ..., n2, where n2 is any number;
c) in the current fixation mode i, they will test the modes of biological removal of nitrogen and phosphorus from wastewater at one point of each of the n2 intervals of possible flow rates Qii, determine the daily flow rate of wastewater Qi, j entering the treatment, the concentration C of _BOD i, j of pollution in the initial water according to the biochemical oxygen demand, the concentration of contaminants in the purified water according to the controlled ingredients Ck, i, j, the average concentration of sludge in the tank facilities Xi, j, where j = 1, 2, 3 ..., n2, k = 1, 2, 3 ..., n3, where n3 is the number of controlled ingredients;
d) in the current fixation mode i at the tested points of each of the n2 intervals of possible costs Qii calculate the load on silt N _BOD i, j = Qi, j · C _BOD i, j / (V · Xi, j), where V is the volume of capacitive facilities;
e) in the current fixation mode i, in the same coordinate axes, plots of the dependences of the concentrations of contaminants in the treated water are plotted against the controlled ingredients Ck, i, j on the load on sludge N _BOD i, j;
f) the dependencies constructed in step e) search for the range of the working load for sludge from N _{BOD, min} to N _{BOD, max} , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp, while if this range is not found , then at least the flow rate of activated sludge return from the secondary sumps at a new level Qci, i + 1 and / or the flow rate into the denitrifier of the circulating flow of sludge mixture from the nitrification outlet at a new level Qci, i + 1, is changed and fixed, the sequence of operations with (b) by (e) repeat until detected the range of the working load on sludge from N _{BOD, min} to N _{BOD, max} , at which the required degree of water purification is achieved for all controlled ingredients Ck, mp, or additional purification systems for ingredients m are used, for which the range of working load on sludge, providing the required degree of purification for the specified ingredients was not found or is outside the range of the working load for sludge from N _{BOD, min1} to N _{BOD, max1} , at which the required degree of water purification is achieved for most controlled ingredients, where m = 1, 2, 3 ... , n3;
g) in the future, biological removal of nitrogen and phosphorus from wastewater is carried out in the range of sludge working loads from N _{BOD, min} to N _{BOD, max} or N _{BOD, min1} to N _{BOD, max1} . 2. The method of ensuring the reliability of wastewater treatment from nitrogen and phosphorus compounds according to claim 1, characterized in that the testing modes of biological removal of nitrogen and phosphorus from wastewater is carried out on a computer model. 3. The method of ensuring the reliability of wastewater treatment from nitrogen and phosphorus compounds according to claim 1, characterized in that the concentration of pollutants in the treated water is based on ammonium nitrogen C _NH4 , nitrogen nitrates C _NO3 , phosphates C _PO4 as controlled concentrations of pollution. 4. A method for ensuring the reliability of wastewater treatment from nitrogen and phosphorus compounds according to claim 1, characterized in that the concentration of pollutants in the treated water according to total nitrogen C _Ntotal , total phosphorus C _Ptot . 5. A method for ensuring the reliability of wastewater treatment from nitrogen and phosphorus compounds according to claim 1, characterized in that at step e) a range of sludge load from N _{BPK, min} to N _{BPK, max} is searched for, in which for all controlled ingredients the following degree of water purification is achieved Ck, mp / Kz, where Kz is the technological reserve coefficient, Kz> 1. 6. A method for ensuring the reliability of wastewater treatment from nitrogen and phosphorus compounds according to claim 3 or 4, characterized in that treatment systems with chemical reagents are accepted as additional purification systems for phosphates C _PO4 and total phosphorus C _Rosch .

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