RU2775470C1 - Method for determining the concentration of recycling sludge in a system for biological waste water treatment - Google Patents

Abstract

FIELD: water treatment.

SUBSTANCE: invention relates to the field of water discharge, namely, to methods for modelling apparatus (devices) for biological waste water treatment at sewage treatment facilities. Method for determining the concentration of recycling sludge in a system for biological waste water treatment includes decomposing a secondary settling tank/tanks into a set of n concentrically located subelements with a first and a second output flows, n≥1, located in the course of the flow of the input flow from the centre radially in all directions. Determined next are the mass flow rate of sludge in the input flow of the secondary settling tank/tanks, the flow rates of the first and the second output flows of the concentric subelements of the secondary settling tank/tanks, the rates of deposition of the i^th sludge fraction settling in the i^th subelement of the secondary settling tank, the mass flow rate of sludge in the first and the second output flows of the i^th subelement of the secondary settling tank, the mass flow rate of sludge in the first and the second output flows of the i^th subelement of the secondary settling tank, and the concentration of sludge in the first and the second outlet flows of the secondary settling tank.

EFFECT: proposed method for determining the concentration of contaminants in treated waste water and the concentration of sludge in the recycle flow of the system for biological waste water treatment allows determining the concentrations of substances in the flows accounting for the processes occurring in the apparatus (devices), providing an improvement in the quality and reliability of biological waste water treatment.

1 cl, 4 dwg

Description

The method relates to the field of water disposal, as well as methods for determining the concentration of suspended solids after biological wastewater treatment at sewage treatment plants.

To the disadvantage of existing calculation methods, for example, according to SP 32.13330.2018 “Sewerage. External networks and structures ”or according to the textbook“ Deep treatment of urban wastewater ”(authors B.G. Mishukov, E.A. Solovieva ed. 2014), refers to the fact that the calculation of the secondary sump is carried out according to the parameters of treated wastewater at its boundaries . The parameters determined in the implementation of such methods are largely average values and do not take into account the processes occurring inside. At the same time, the concentration of sludge in the recirculation flow from the middle of the secondary clarifier has a strong influence on the quality of the removal of pollutants from wastewater, and its precise determination in these methods is not the goal and is performed conditionally. Therefore, the use of these methods does not allow predicting and managing the process of wastewater treatment.

The closest analogue to the claimed method is the patent for invention RU No. 2656687, System and method for modeling and calculating chemical-technological systems, G06N 7/00, G09B 25/02, publ. 06/06/2018, Bull. No. 16, including the following steps:

a) creation by the user of a new chemical-technological scheme or selection and / or editing by the user of a created or existing chemical-technological scheme from a set of chemical-technological schemes through the input-output interface on the client side, stored on the server, where the chemical-technological scheme describes the chemical-technological scheme; a technological system characterized by at least one chemical-technological process, moreover, the chemical-technological scheme consists of modules of the chemical-technological scheme connected by input and output flows, and the calculation of the devices of the chemical-technological scheme is performed by calculation modules implemented as elements of the Service Tires Enterprises;

b) selecting and adding modules of the chemical flow diagram to the chemical flow diagram and specifying by the user the input parameters of the chemical flow diagram and / or parameters of the modules of the chemical flow diagram, including at least the parameters of the input stream and / or output stream for the chemical - technological scheme, and/or parameters of devices of the chemical-technological scheme, and/or parameters for modules of the chemical-technological scheme, and/or selection of calculation modules for modules of the chemical-technological scheme;

c) transferring the data obtained in paragraphs a) and b) with a description of the chemical-technological scheme to the server in the form of an HTTP request for calculating the chemical-technological scheme;

d) transformation of the data received from the user on the server into a configuration task in the Enterprise Service Bus format;

e) carrying out the calculation by processing the configuration task by the Service Bus of the Enterprise, wherein the chemical-technological flows are represented by messages of the Service Bus of the Enterprise and the modules of the chemical-technological scheme are represented by elements of the Service Bus of the Enterprise;

f) sending the results of the calculation of the chemical-technological scheme to the client side in the form of an HTTP response.

There is a development option when the parameters of the modules of the chemical-technological scheme include the task of at least one input stream of the module of the chemical-technological scheme.

There is a development option, when at least one calculation module of the chemical-technological scheme corresponds to the module of the chemical-technological scheme, made in the form of a software module implemented in a programming language.

There is a development option when the calculation modules are created by the user in the language of the Enterprise Service Bus in addition to the previously created calculation modules.

There is a development option when the modules of the chemical-technological scheme convert the incoming streams into the outgoing streams of the apparatus.

There is a development option when the user interface is a web interface

There is a development option when the calculation modules are converted on the server into elements of the Enterprise Service Bus.

There is a development option when the characteristics of the flows of the chemical-technological scheme are modeled by the messages of the Enterprise Service Bus, which include the chemical-technological parameters of the flows, such as: pressure; temperature; consumption, concentration of chemical elements.

There is a development option when the Enterprise Service Bus can be built using the Spring Integration framework for integrating enterprise applications based on the SpringFramework core.

There is a development option when the description of the chemical-technological scheme is included in the configuration file, presented in a data saving format, such as XML.

There is a development option when, after the completion of the calculation of the chemical-technological scheme, the results of the calculation are added to the configuration file in the form of properties of the elements of the Service Bus of the Enterprise.

There is a development option when the configuration file is stored on the server and can be requested by the user to restore the original chemical-technological scheme.

There is a development option when the description of the chemical-technological scheme includes a simplified description of the modules of the chemical-technological scheme, allowing for a quick calculation of the chemical-technological scheme.

There is a development option when the configuration file is stored in the database.

There is a development option when the calculation modules are connected to the server to calculate at least one module of the chemical-technological scheme.

There is a development option when the modules of a chemical-technological scheme can be arranged into chains of modules of a chemical-technological scheme that describe at least one apparatus, and such a chain is calculated by at least one calculation module selected for it.

There is a development option when the chain of modules of the chemical-technological scheme is stored on the server separately from the chemical-technological scheme in the form of a block of a chemical-technological scheme or a module of a chemical-technological scheme.

There is a development option where a chain of chemo-technological circuit modules can be added to a chemo-technological circuit as a block of chemo-technological circuit modules or a chemo-technological circuit module.

There is a development option when the characteristics of the chain of modules of the chemical-technological scheme calculated on the server, including input, output and intermediate flows and their characteristics, are stored together with the chain of modules and are used to calculate the chemical-technological scheme into which such a chain of modules of the chemical-technological scheme has been added.

There is a development option when the element of the Service Bus of the Enterprise is associated with the module of the chemical-technological scheme, with the help of which the calculation of this module of the chemical-technological scheme is performed on the server.

There is a development option when the calculation of the module of the chemical-technological scheme is carried out on different servers, depending on the settings of the Enterprise Service Bus.

This method is characterized by a limited scope, since it allows only modeling and calculation of the circuit according to the configuration task (without developing a model of the entire system) by using calculation modules that convert incoming flows into outgoing flows of elements and chains of circuit elements. For this reason, only inlet and outlet flows are known, characterized at least by flow rates and substance concentrations. In this case, the values of the parameters inside each element remain unknown. For some technological processes, this is a significant limitation. In particular, for technological schemes of biological wastewater treatment, in which automated control is carried out according to algorithms that provide for maintaining the concentration of substances at the required level not only at the outlet, but also inside the elements. To do this, they must not only be measured, but also predicted. For example, when determining the concentration of recirculating sludge pumped out of secondary clarifiers, where it depends on its flow rate, as well as the flow rate and concentration of the outlet stream. Using the known method, the concentration of recirculating sludge cannot be determined.

The objective of the present invention is to expand the scope of the known method.

The problem is solved so that in a known way, including at least the following steps:

a) creating a new scheme or editing a created or existing scheme describing the system, and the scheme consists of elements of the scheme and chains of elements of the scheme, connected by input and output flows, characterized by at least the flow rates and concentrations of substances, and the calculation of elements and chains of elements the scheme is performed by the design modules of the elements and the design modules of the chains of the circuit elements, respectively,

b) setting the input parameters of the circuit and / or measured parameters of circuit elements and chains of circuit elements, the choice of calculation modules for circuit elements and chains of circuit elements,

c) carrying out calculations using the data obtained in paragraphs a) and b),

d) presentation of calculation results,

according to the present invention:

as a system, a biological wastewater treatment system is adopted,

as a scheme, a technological scheme of a biological wastewater treatment system is taken,

насосную станцию циркуляции активного ила, при этом, выходной поток вторичного отстойника/отстойников разделяют на первый

и второй

выходные потоки, при этом

at least an aerotank/aerotanks, a secondary settling tank/settlers are taken as elements of the circuit, having a circular shape in plan, made so that the output stream from the aerotank/aerotanks is the input stream of the secondary settler/settlers

activated sludge circulation pumping station, while the output stream of the secondary clarifier / clarifiers is divided into the first

and second

output streams, while

perform decomposition of the secondary clarifier/clarifiers into a set of concentrically located and sub-elements having the first and second output flows, n≥1, and located along the inlet flow from the center in all directions in the radial direction, so that

является входным потоком i-го подэлемента, i=1, 2, …, n,

first output stream of (i-1)th subelement

is the input stream of the i-th subelement, i=1, 2, …, n,

the first sub-element of the secondary clarifier / clarifiers is connected to the inlet stream of the secondary clarifier / clarifiers, and the last sub-element of the secondary clarifier / clarifiers is connected to the first output stream of the secondary clarifier / clarifiers,

the second output streams of each sub-element are connected to the second output stream of the secondary clarifier/settlers, which is the input stream of the activated sludge circulation pumping station,

sludge concentrations are taken as concentrations of substances.

Besides:

as set parameters of the secondary clarifier/clarifiers take

overall dimensions, at least the radius of the secondary clarifier R _max and the depth H _{c of} the clarifier,

the concentration of sludge in the inlet stream of the secondary clarifier / clarifiers X ₀ equal to the concentration of sludge in the outlet stream of the aerotank / aerotanks,

costs of the first Q ^I and the second Q ^II of the output streams of the secondary clarifier / clarifiers,

а i=1, 2, …, n,as the set parameters of the chains of subelements of the secondary clarifier, internal t _i and external r _i+1 radius are taken, r ₁ =dR, r _i+1 =r _i +dR, and r _n =R _max , where

and i=1, 2, …, n,

average sedimentation rate of sludge in the secondary clarifier/clarifiers u _cp ,

гидравлической крупности ила во входном потоке вторичного отстойника,distribution function

hydraulic size of sludge in the inlet stream of the secondary clarifier,

as the calculation module of chains of circuit elements, a module / modules is used, made / made with the ability to determine

mass flow rate of sludge _Min in the inlet stream of the secondary clarifier / clarifiers,

и второго

выходного потоков концентрических подэлементов вторичного отстойника/отстойников, при этом

и

first

and second

outlet flows of concentric sub-elements of the secondary clarifier/clarifiers, while

and

в первых выходных потоках в i-ом подэлементе с векторами, направленными горизонтально от центра вторичного отстойника/отстойников во все стороны в радиальном направлении и скоростей движения

во вторых выходных потоках в i-ом подэлементе с векторами, направленными вертикально вниз,movement speeds

in the first output streams in the i-th subelement with vectors directed horizontally from the center of the secondary clarifier / clarifiers in all directions in the radial direction and movement speeds

in the second output streams in the i-th subelement with vectors directed vertically down,

settling rates of the i-th sludge fraction settling in the i-th subelement of the secondary clarifier

и втором

выходных потоках i-го подэлемента вторичного отстойника,mass flow of sludge in the first

and second

output streams of the i-th subelement of the secondary clarifier,

и втором

выходных потоках вторичного отстойника, определяемых, как

и

mass flow of sludge in the first

and second

outlet streams of the secondary clarifier, defined as

and

sludge concentrations in the first X ^I and second X ^II outlet stream of the secondary clarifier.

Distinctive features of the claimed Method for determining the concentration of recycled sludge in a biological wastewater treatment system are:

1. Choice as a biological wastewater treatment system;

2. Choice as a scheme of the technological scheme of the biological wastewater treatment system;

3. Adoption as circuit elements of at least an aerotank/aerotanks, a secondary settling tank/settlers having a circular shape in plan, made so that the outlet stream from the aerotank/aerotanks is the input stream of the secondary settling tank/settlers, an activated sludge circulation pumping station ;

4. Separation of the output stream of the secondary clarifier/clarifiers into the first and second output streams;

5. Performing the decomposition of the secondary clarifier/clarifiers into a set of concentrically arranged sub-elements having the first and second output flows and located along the inlet flow from the center in all directions in the radial direction;

6. Connection of the first output stream of the i-1st subelement with the input stream of the i-th subelement;

7. Connecting the first sub-element of the secondary clarifier(s) to the inlet stream of the secondary clarifier(s);

8. Connecting the last sub-element of the secondary clarifier(s) to the first outlet stream of the secondary clarifier(s);

9. Connecting the second output streams of each sub-element of the secondary settler/settlers with the second output stream of the secondary settler/settlers;

10. Connection of the second outlet stream of the secondary clarifier/clarifiers with the inlet stream of the activated sludge circulation pumping station;

11. Selection of sludge concentrations as concentrations of substances;

12. Additional choice as parameters of the secondary settling tank/settlers of overall dimensions, at least the radius of the secondary settling tank R _max and its depth H _ots ;

13. Additional selection as a setting parameter for the secondary clarifier/clarifiers of the concentration of sludge in the incoming stream of the secondary clarifier/clarifiers;

14. Additional choice as a parameter of the secondary clarifier/clarifiers of the first and second output streams of the secondary clarifier/clarifiers;

15. Additional choice as a set parameter of chains of sub-elements of the secondary clarifier of the inner and outer radius of the sub-element of the secondary clarifier;

16. Additional choice as a set parameter of the average sedimentation rate of sludge in the secondary clarifier / clarifiers;

17. Additional choice as a set parameter of the distribution function of the hydraulic size of the sludge,

18. Application as a calculation module of chains of elements of the circuit of the module / modules, mass flow or inlet stream of the secondary clarifier / clarifiers;

19. Application as a calculation module of chains of elements of the scheme of the module/modules, made/made with the ability to determine the flow rates of the first and second output streams of the concentric sub-elements of the secondary clarifier/clarifiers;

20. Application as a calculation module of chains of elements of the circuit of a module / modules, made / made with the possibility of determining the speeds of movement in the first output streams in the subelements of the secondary clarifier with vectors directed horizontally from the center of the secondary clarifier / clarifiers in all directions in the radial direction and the second output streams with vectors directed vertically down;

21. Application as a calculation module of chains of elements of the circuit of the module/modules, made/made with the ability to determine the settling rates of the silt fraction settling in each sub-element of the secondary clarifier;

22. Application as a calculation module of chains of elements of the circuit of the module / modules, made / made with the ability to determine the mass flow rate of sludge in the first and second output streams of each sub-element of the secondary clarifier;

23. Use as a calculation module of a module / modules made / made with the ability to determine the mass flow rate of sludge in the first and second output streams of the secondary clarifier,

24. Use as a calculation module of a module/modules made/made with the ability to determine the concentration of sludge in the first and second outlet stream of the secondary clarifier.

According to the information available to the authors, the distinguishing feature No. 1, 2, 3, 4 is known in the technical literature, while the rest are not, which meets the condition of patentability "novelty".

The combined use in the claimed device of these distinctive features allows you to get a positive effect, which is that the scope of the known method is expanding, tk. it can be used to determine the parameters of the technological process of wastewater treatment, taking into account changes in the characteristics of wastewater along the flow of flows in the secondary clarifier/clarifiers. This is achieved due to the presence of distinguishing features No. 1-24, tk. as a result of the application of the present invention, it becomes possible to characterize the treated water and the recirculating flow in the wastewater treatment process by taking into account the change in flow parameters during the deposition of sludge in all elements of the secondary clarifier/clarifiers.

The method proposed by the authors differs from the prototype.

In FIG. 1 shows an example of a process flow diagram.

In FIG. 2 shows an example of a variant of setting the circuit parameters.

In FIG. 3 shows a diagram of the sub-elements of the secondary clarifier with defined parameters.

In FIG. 4 shows an example of a variant of the results of determining the concentration of recycled sludge.

Implementation of the invention.

At step a) create a new scheme (Fig. 1) or edit the created or existing scheme that describes the system, and the scheme consists of circuit elements and chains of circuit elements connected by input and output flows, characterized at least by flow rates and concentrations of substances .

Wherein:

- as a system take a system of biological wastewater treatment;

- as a scheme, a technological scheme of a biological wastewater treatment system is taken, see FIG. one;

- at least the aerotank/aerotanks 1, the secondary settling tank/settling tanks 2, having a round shape in plan, are taken as elements of the scheme, while

- stream 3 is the output stream from the aeration tank / aeration tanks 1 and the input stream of the secondary clarifier / clarifiers 2,

- the output stream of the secondary settler/settlers 2 is divided into the first 4 and second 5 output streams of the secondary settler/settlers;

- the second output stream 5 of the secondary clarifier/settlers is the input stream of the activated sludge circulation pumping station 6.

In accordance with the present invention, various options for using the second outlet stream 5 of the secondary clarifier/settlers are allowed, for example, when the activated sludge circulation pump station 6 delivers activated sludge through pressure pipelines 7 and 8 to different points of the aerotank/aerotanks 1 and/or through pressure pipelines 7 and 9 - submit sludge for processing.

At step b), the input parameters of the circuit and/or the measured parameters of the circuit elements and chains of circuit elements are set, the calculation modules for the circuit elements and chains of circuit elements are selected.

In this case (Fig. 2):

as the concentration of substances, the concentration of sludge is taken, which, for example, can be determined by the results of an experiment or using sensors, the principle of operation of which is based on the combined method of absorption of scattered infrared light or by any other known method;

the concentration of sludge X ₀ in the inlet stream 3 of the secondary clarifier/clarifiers 2 is taken equal to the concentration of sludge in the outlet stream of the aerotank/aerotanks 1, which can be determined from the results of the experiment or using sensors, the principle of operation of which is based on the combined method of absorption of scattered infrared light or any in another known way;

take overall dimensions, at least the radius R _max of the secondary clarifier/clarifiers 2 and the depth H _ots that can be determined from the design and estimate documentation, for example R _max = 9 m and H _ots = 3.7 m;

take the costs of the first Q ^I and second Q ^II output streams of the secondary clarifier/clarifiers 2, which can be determined from the design estimates or at the stage of commissioning, for example Q ^I =187.5 m ³ /h and Q ^II =190 m ³ / h,

a i=1, 2, …, n, например n=9, dR=1 м;as the parameters of the chains of sub-elements of the secondary clarifier/clarifiers 2, internal r _i and external r _i+1 radius, r ₁ =dR, r _i+1 =r _i +dR, ar _n =R _max , where

ai=1, 2, …, n, for example n=9, dR=1 m;

take the average speed u _cp sedimentation of sludge in the secondary clarifier/clarifiers 2, which can be determined by any known method, for example, according to the results of an experimental study of the sedimentation properties of sludge;

гидравлической крупности ила, например по результатам экспериментального исследования седиментационных свойств ила.take a distribution function

hydraulic fineness of sludge, for example, according to the results of an experimental study of the sedimentation properties of sludge.

At stage c), using the data obtained in paragraphs a) and b), the elements and chains of circuit elements are calculated by the calculation modules of the elements and the calculation modules of the circuit element chains.

In this case (Fig. 3):

- perform decomposition of the secondary clarifier/clarifiers 2 into a set of concentrically located n subelements 10, 11, ... 18, n≥1, located along the inlet stream 3 from the center in all directions in the radial direction, so that:

является входным потоком 2-го подэлемента вторичного отстойника/отстойников 11, первый выходной поток 20 2-го подэлемента вторичного отстойника/отстойников 11

является входным потоком 3-го подэлемента вторичного отстойника/отстойников 12 и т.д., при этом

- the first output stream 19 of the 1st sub-element of the secondary clarifier / clarifiers 10

is the input stream of the 2nd sub-element of the secondary clarifier / clarifiers 11, the first output stream 20 of the 2nd sub-element of the secondary clarifier / clarifiers 11

is the input stream of the 3rd sub-element of the secondary settler/settlers 12, etc., while

- the first sub-element 10 of the secondary settler/settlers is connected to the input stream of the secondary settler/settlers 3, and the last sub-element 18 is connected to the first output stream of the secondary settler/settlers 4;

- the second output streams 27, 28, ..., 35 of each sub-element 10, 11, ..., 18, respectively, are connected to the second output stream 5, which is the input stream of the activated sludge circulation pumping station 6;

As a design module for chains of circuit elements, a module / modules is used, made / made with the ability to determine:

- mass flow rate of sludge in the inlet stream of the secondary clarifier/clarifiers,

выходного потока концентрических подэлементов вторичного отстойника/отстойников (см. фиг 4, строка 37)- expenses of the second

the outlet flow of the concentric sub-elements of the secondary clarifier/clarifiers (see FIG. 4, line 37)

wherein

выходного потоков концентрических подэлементов вторичного отстойника/отстойников (см. фиг 4, строка 38)- expenses of the first

the output streams of the concentric sub-elements of the secondary clarifier/clarifiers (see Fig. 4, line 38)

wherein

в i-ом подэлементе вторичного отстойника в первых выходных потоках с векторами, направленными горизонтально от центра вторичного отстойника/отстойников во все стороны в радиальном направлении (см. фиг 4, строка 39)- movement speeds

in the i-th subelement of the secondary clarifier in the first output streams with vectors directed horizontally from the center of the secondary clarifier / clarifiers in all directions in the radial direction (see Fig. 4, line 39)

в i-ом подэлементе вторичного отстойника во вторых выходных потоках с векторами, направленными вертикально вниз (см. фиг 4, строка 40)- movement speeds

in the i-th subelement of the secondary clarifier in the second output streams with vectors directed vertically downwards (see Fig. 4, line 40)

- sedimentation rates of the i-th fraction of sludge settled in the i-th subelement of the secondary clarifier (see Fig. 4, line 41)

во втором выходном потоке в i-ом подэлементе вторичного отстойника (см. фиг 4, строка 42)- mass flow of sludge

in the second output stream in the i-th subelement of the secondary clarifier (see Fig. 4, line 42)

в первом выходном потоке в i-ом подэлементе вторичного отстойника (см. фиг 4, строка 43)- mass flow of sludge

in the first output stream in the i-th subelement of the secondary clarifier (see Fig. 4, line 43)

в первом выходном потоке вторичного отстойника- mass flow of sludge

in the first outlet stream of the secondary clarifier

в втором выходном потоке вторичного отстойника- mass flow of sludge

in the second outlet stream of the secondary clarifier

- concentrations of sludge X ^I in the first outlet of the secondary clarifier

во втором выходном потоке вторичного отстойника- sludge concentration

in the second outlet stream of the secondary clarifier

At stage d) present the results of calculations,

Wherein

- the concentration of sludge X ^I in the first outlet stream of the secondary clarifier / clarifiers take

- concentrations of sludge X ^II in the second outlet stream of the secondary clarifier / clarifiers are taken

The technical result consists in expanding the scope of the known method, which makes it possible to determine the parameters of the output streams, taking into account the processes in the apparatuses (devices), which makes it possible to improve the quality and reliability of biological wastewater treatment.

Thus, the proposed method is characterized by "industrial applicability".

Claims (29)

A method for determining the concentration of recycled sludge in a biological wastewater treatment system, comprising at least the following steps: a) creating a new scheme or editing a created or existing scheme describing the system, and the scheme consists of elements of the scheme and chains of elements of the scheme, connected by input and output flows, characterized by at least the flow rates and concentrations of substances, and the calculation of elements and chains of elements the scheme is performed by the design modules of the elements and the design modules of the chains of the circuit elements, respectively, b) setting the input parameters of the circuit and / or measured parameters of circuit elements and chains of circuit elements, the choice of calculation modules for circuit elements and chains of circuit elements, c) carrying out calculations using the data obtained in paragraphs a) and b), d) presentation of calculation results, characterized in that as a system, a biological wastewater treatment system is adopted, as a scheme, a technological scheme of a biological wastewater treatment system is taken, at least an aerotank/aerotanks, a secondary settling tank/settlers are taken as elements of the circuit, having a circular shape in plan, made so that the output stream from the aerotank/aerotanks is the input stream of the secondary settler/settlers

activated sludge circulation pumping station, at the same time, the output stream of the secondary clarifier / clarifiers is divided into the first Q ^I and the second Q ^II output flows, while

perform the decomposition of the secondary clarifier / clarifiers into a set of concentrically located n subelements, having the first and second output flows, n≥1, and located in the direction of the input flow from the center in all directions in the radial direction so that first output stream of (i-1)th subelement

is the input stream of the i-th subelement, i=1, 2, …, n,

the first sub-element of the secondary clarifier / clarifiers is connected to the inlet stream of the secondary clarifier / clarifiers, and the last sub-element of the secondary clarifier / clarifiers is connected to the first output stream of the secondary clarifier / clarifiers, the second output streams of each sub-element are connected to the second output stream of the secondary clarifier/settlers, which is the input stream of the activated sludge circulation pumping station, as the concentrations of substances take the concentration of sludge, in this case, as the set parameters of the secondary clarifier / clarifiers, overall dimensions, at least the radius of the secondary clarifier R _max and the depth H _{c of} the clarifier, the concentration of sludge in the inlet stream of the secondary clarifier/settlers X ₀ equal to the concentration of sludge in the outlet stream of the aerotank/aerotanks, costs of the first Q ^I and the second Q ^II of the output streams of the secondary clarifier / clarifiers, as the set parameters of the chains of subelements of the secondary clarifier, internal r _i and external r _i+1 radius are taken, r ₁ =dR, r _i+1 =r _i +dR, and r _n =R _max , where

ai=1, 2, …, n, the average rate of sedimentation of sludge in the secondary clarifier / clarifiers u _cf , distribution function

hydraulic size of sludge in the inlet stream of the secondary clarifier, as a calculation module of chains of circuit elements, a module / modules is used, made / made with the ability to determine, mass flow rate of sludge M _in in the inlet stream of the secondary clarifier / clarifiers, first

and second

outlet flows of concentric sub-elements of the secondary clarifier/clarifiers, while

and

movement speeds

in the first output streams in the i-th subelement with vectors directed horizontally from the center of the secondary clarifier / clarifiers in all directions in the radial direction and movement speeds

in the second output streams in the i-th subelement with vectors directed vertically down, settling rates of the i-th sludge fraction settling in the i-th subelement of the secondary clarifier

mass flow of sludge in the first

and second

output streams of the i-th subelement of the secondary clarifier, mass flow of sludge in the first

and second

outlet streams of the secondary clarifier,

and

sludge concentrations in the first X ^I and second X ^II outlet stream of the secondary clarifier.

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