RU2691511C2 - Sewage treatment station - Google Patents

Abstract

FIELD: cleaning devices.SUBSTANCE: invention is intended for sewage treatment. Wastewater treatment plant contains a vertical cylindrical double-shell activation tank, in the central part of which there are two mutually parallel dividing walls (19), limiting the central part between them for aerobic stabilization of activated sludge and at the same time separating in relation to inner case (18) of the activation reservoir two symmetrically arranged functional spaces for wastewater and purification cultures, in each of which secondary clarifiers (5) are separately installed. Secondary clarifiers (5) are made tapering downwards. Along the axis of each clarifier (5) is hollow cylinder (14), connected to the inner space of the activation reservoir using transverse supply pipe (13), and to the inner space of secondary clarifier (5), to which aero tank (4) is located on the outside. Perforated compressed air piping is laid along the bottom surface of the activation tank. Central part of the wastewater treatment plant is vertically divided into several interconnected through holes of the chambers, which form selector (2), connected by its entrance to the outlet of a large sewage separator or the outlet of a drum separator located outside the activation tank. Selector (2) is connected by its output to denitrifier (3) located between two housings (17, 18) of the activation reservoir. In the partitions of selector (2), surface (21) and bottom (22) closures are installed, made with the ability to start and ensure smooth operation of the station at 10 % of the incoming wastewater from the station's nominal power. In denitrifier (3) there are agitators (10) arranged to enable movement of the mixture of waste water and sludge throughout its volume. Denitrifier (3) is connected to the part of the activation tank space in the aero tank area (4) by means of through holes, into which the connection with secondary settling tank (5) is brought out with the help of transverse supply pipe (13). Lower space of secondary clarifier (5) is connected to the central part of the wastewater treatment plant.EFFECT: invention allows to increase the arsenal of technical means for wastewater treatment with the ability to create a compact unit located in one tank.12 cl, 3 dwg

Description

TECHNICAL FIELD TO WHICH INVENTION RELATES.

The invention relates to wastewater treatment.

BACKGROUND

Modern solutions of most wastewater treatment plants contain a variety of separate construction and technological facilities and components, interconnected by means of pipelines, pumping equipment and pipeline valves. The disadvantages of such solutions are the use of large land plots and periodic construction work (for example, earthworks, reinforcement, installation of formwork, concreting, etc.) All these factors lead to increased investment costs and an increase in construction time. From a technological point of view, a frequent drawback of such cleaning stations is insufficient or partial biological treatment, which entails increased power consumption caused by repeated pumping, mixing and caused by a more complex process. As a result of this wastewater treatment process, odors appear; unwanted insects, larvae appear in the structures and technological units of the station; during operation, the cleaning station has an increased noise level.

Virtually each of the known cleaning processes has fundamental flaws. For example, the so-called "SBR" process at first glance integrates several processes in a single tank of a sewage treatment plant, but nonetheless faces problems associated with the variability of the surface level, sludge leaching, as well as energy losses at low water levels and accompanying aeration . Other known processes are often implemented on large-area construction sites with a multitude of communications, which leads, among other things, to complicating maintenance in the operation of equipment and the management of technological processes, including sampling.

As the closest analogue of the invention, a wastewater treatment plant is selected, disclosed in patent document RU No. 2338697 C2, November 20, 2008

DISCLOSURE OF INVENTION

The aim of the invention is the creation of an integrated construction and technological equipment of the wastewater treatment plant, eliminating a number of the above disadvantages.

The technical result of the claimed invention is to increase the Arsenal of technical means for wastewater treatment with the ability to create a compact site located in one tank.

The subject of this invention is the layout of the wastewater treatment plant, containing a vertical cylindrical two-body aerotank (activation tank). The essence of the invention is that in the central part of this reservoir there are two mutually parallel dividing walls, limiting the central part of the wastewater treatment plant located between them for aerobic stabilization of activated sludge and at the same time separating two symmetrical functional spaces for wastewater water and purification crops, each of which is separately installed secondary settlers, tapering downwards. Inside each settler, a hollow cylinder is placed along the axis, connected both to the inside of the activation tank (using a transverse supply pipe) and to the inside of the secondary settling tank, to which the aero tank adjoins on the outside. Perforated compressed air piping is laid along the bottom surface of the activation tank (aerotank). In the central partition of the aerotank, bottom closures are located that simplify the operation of the station and optimize wastewater treatment. The central part of the wastewater treatment plant is vertically divided into several interconnected through holes of the chambers. These chambers form a selector connected by its entrance to the exit of a large sewage separator or the output of a drum separator located outside the tank of a wastewater treatment plant. In the partitions of the selector, surface and bottom closures are installed that allow launching and uninterrupted operation of the station at 10% of the wastewater entering the treatment plant from the rated power of the station. With its output, the selector is connected to a denitrification space in the reservoir (denitrifier) located between the two housings of the activation reservoir. In the denitrifier, there are agitators arranged to enable movement of the mixture of waste water and sludge throughout the entire volume of the denitrifier. This denitrification space is connected by means of through holes to a part of the space of the activation tank in the aeration area, into which the connection to the secondary settling tank is led by means of a transverse supply pipe. In this case, the lower space of the secondary settling tank is connected to the central part of the sewage treatment plant. The walls of the tank of the wastewater treatment plant are made of a material selected from the group consisting of concrete, stainless steel and plastic.

The advantage of the present invention is that the entire system of wastewater treatment plant is a compact unit located in one tank (one building object), which eliminates the need for multiple bookmarks building objects. This solution makes rational use of space with increased cleaning efficiency and reduced energy consumption of the wastewater treatment process.

Secondary clarifiers have a conical shape with an inclination of the walls of about 60 °, which is more advantageous for the cleaning process. A variant of the performance of secondary settlers can be slop tanks having a flat bottom, on which are installed the buildings with bevelled walls, having the shape of a pyramid, a cone, a truncated pyramid or a truncated cone, with an inclination of the walls at an angle of about 60 °. The form of oblique oblique surfaces (at an angle of approximately 60 °) for slop tanks is used to create a more optimal velocity flow of the activation mixture (water and activated sludge) arising from the collision of microscopic bubbles emanating from the bottom through diffusers with external sloping walls of slop tanks. Thus, thorough mixing of the activation mixture is ensured and a homogeneous mixture of sludge and water is formed.

The lower space of the secondary clarifiers can be connected through an activated sludge regenerator in the central part of the wastewater treatment plant with one of the three-stage selector chambers. Thus, recycled activated sludge can be fed into the selector from the bottom of the secondary clarifier. The wastewater treatment plant contains an even number of secondary sedimentation tanks (which is more profitable), at least two, most often four, but maybe eight. Each settling tank in the upper part is equipped with a clarified water gutter, which can be connected to the final water treatment compartment.

The lower space of slop tanks can also be connected to the denitrifier. The extraction of activated sludge, free from dissolved oxygen, from the bottom of the secondary clarifiers to the denitrifier, resulting from the operation of the denitrifying agitators, increases the efficiency of denitrification.

The walls of the sewage treatment plant can be made of concrete or metal or plastic. Bottom closures can be located at the bottom of the blind dividing wall.

At the bottom of the denitrifier can be located pipeline additional oxidizing system. The fact is that at lower ambient temperatures the denitrification process can be suppressed. To this end, the denitrifier of the sewage treatment plant is equipped with an additional oxidizing system, which ensures the process of ordinary biological water purification in this space.

BRIEF DESCRIPTION OF THE DRAWINGS

The attached drawings depict an example of a wastewater treatment plant device based on the present invention.

FIG. 1 is a schematic top view of the layout of a wastewater treatment plant.

FIG. 2 shows a vertical section of this station 1-1.

FIG. 3 shows a vertical section of this station 2-2.

IMPLEMENTATION OF THE INVENTION

Further to refer to the various components of the claimed station, the following reference symbols are used:

1 - wastewater inlet for treatment;

2 - three-stage selector;

3 - denitrifier;

4 - aero tank;

5 - secondary settling tank;

6 - activated sludge regenerator;

7 - aerobic stabilizer of active sludge;

8 - compartment of circulating active sludge pumps;

9 - filter compartment after-treatment (final water purification);

10 - mixing device (mixer);

11 - aerators (microbubble diffusers);

12 - wastewater outlet;

13 - cross connecting (supply) pipeline;

14 - central distribution pipe;

15 - circulation active sludge system pipeline;

16 - system for collecting clarified waste water;

17 - outer case (outer wall of the cylindrical tank);

18 - inner case (inner wall of the cylindrical tank);

19 - walls of the central process compartment;

20 - deaf dividing wall of the aerotank;

21 - surface shutter (overflow);

22 - bottom valve (flooded);

The wastewater treatment plant contains a vertical cylindrical activation double-shell reservoir made of concrete, plastic or metal, which contains an outer casing (17) and an inner casing (18) concentrically located with respect to the reservoir of smaller diameter. The diameter of the outer shell (17) of the tank can be in a wide range from two to several tens of meters. The width of the space between the inner case (18) and the outer case (17) is in the range from one to about five meters, depending on the application in specific conditions. The height of both walls of the hulls (17, 18) of the tank is approximately the same and can be from two to ten meters. Their thickness depends on the chosen material of the structure and ranges from a few millimeters (in the case of steel) or centimeters (in the case of structural plastics — for example, from six to twelve centimeters of propylene) to several tens of centimeters (in the case of concrete, up to fifty centimeters) . In the inner tank (activation), limited by the inner case (18) and the bottom, there are built-in separate technological components of the system, including secondary settling tanks (5), a stabilization tank (aerobic stabilizer of activated sludge (7), regeneration tank (6) and other components will be described in more detail in the following part of the text.

In the inner tank, in its central part, two mutually parallel vertical separation walls (19) are built with a height corresponding to the height of the inner case (18), which limit the central part of the sewage treatment plant to aerobic stabilization of activated sludge. At the same time, these walls divide the internal space of the wastewater treatment plant into two symmetrical halves in such a way as to prevent the free flow of wastewater and the purification culture between the two halves of the internal concentric tank. Secondary clarifiers (5), the number of which is even (most often two, four, but maybe eight), can be symmetrically inserted into the space of an internal concentric tank. The tanks of the settling tanks can be supported on the vertical partition walls (19), and can also be connected with them. The lower part of each secondary clarifier (5) has a conical shape with an inclination of the walls at an angle of approximately 60 ° and a section that tapers downwards. A slop tank can be in the shape of a pyramid or cone. The bottom of the secondary clarifier (5) can be open or closed. Alternatively, the secondary clarifiers (5) may have a flat bottom with plastic or metal bodies in the shape of a pyramid, a cone, a truncated pyramid or a truncated cone with a wall inclination of approximately 60 °, installed on it. In the central part of each segment of the secondary clarifier (5) a central distribution pipe (14) may be located in the form of a vertical plastic hollow cylinder, the bottom of which is open, i.e. the cylinder communicates with the internal space of the secondary clarifier (5). A through (transverse) supply line (13) is brought into this cylinder, the opposite end of which is brought into the inner space of the activation tank between the inner surface of the inner body (18) of the inner concentric tank and the outer walls of the secondary clarifier (5). At the bottom of the inner concentric tank (activation tank) there are aeration elements formed, for example, with perforated silicone hoses, into which compressed air from low-pressure compressors (blowers) is blown through the compressed air pipeline.

Next to the secondary settling tanks (5), aeration tanks (4) are embedded in the activation tank space on the supporting structure, under which perforated compressed air pipeline is connected. From it periodically, at predetermined intervals, compressed air is supplied under the aeration tanks (4), in which silt deposits from the plastic surface of biofilters fall. Thus, an optimal concentration of biological culture is maintained on the surface of biofilters and at the same time in the entire activation reservoir.

Mutag BioChip ™ is used as a biomass carrier.

The central part of the wastewater treatment plant in the space between the two parallel dividing walls (19) of the activation tank is divided by vertical partitions located from the bottom along the entire height of the dividing walls (19) into several chambers that can be equipped with mutual passages that allow water to circulate between them . The bottom of the central part of the station is supplied with compressed air piping, into which aeration elements, formed, for example, with silicone finely perforated hoses, put on plastic (polypropylene, polyvinyl chloride, etc.) pipes with large through holes in the housing, screwed to the compressed air piping . Other technological components of the wastewater treatment plant are described in the description of the functions of the wastewater treatment plant.

Contaminated wastewater flows through a large sewage separator containing, for example, a mechanical suction wall (grid), where solid mechanical particles are separated from the wastewater.

In the event that a large sewage separator is stopped, for example, during a breakdown or maintenance, wastewater is supplied to a drum sewage separator, which serves as a backup flow device for the separation of solid constituents. From the large sewage separator, the waste water flows through a three-stage selector (2), which is connected by its entrance to the large sewage separator outlet or the output of a drum separator located outside the activation tank of the sewage treatment plant. The selector (2) is formed by at least two (three or more is considered more advantageous) located next to each other cameras with vertical partitions, mutually connected holes in their vertical walls, which are located in the central part of the sewage treatment plant between the parallel dividing walls (19) of the activation reservoir. In the partitions of the selector, surface and bottom closures are installed that allow starting and uninterrupted operation of the station with 10% of the wastewater entering the treatment At the bottom of these chambers there is a compressed air pipeline with aerators (11). At the same time, recycled activated sludge from the bottom of the secondary clarifiers (5) is fed into one of these chambers, namely via the activated sludge regenerator (6) connected to it, located in the central part of the station and adjacent to the selector (2). The bottom of the active regenerator or (6) is also equipped with a compressed air pipeline with aerators (11). With its output, the three-stage selector selector (2) is connected to a circular denitrification space (denitrifier) (3) between the inner casing (18) and the outer casing (17) of the tank. In the denitrifier (3), in which there is insufficient free dissolved oxygen, sludge microorganisms begin to take chemically bound oxygen, for example, in nitric acid salts in water, due to which the salt content in water decreases. This process occurs at temperatures above about 6 ° C. In the case of lower ambient temperatures, the denitrification process is significantly inhibited and therefore the denitrifier (3) of the cleaning station is preferably equipped with an additional oxidizing system, which ensures the process of conventional biological water purification in this space (at the bottom of the denitrifier (3) there is a perforated pipeline of additional oxidizing system).

Then, the mixers (10) are integrated into the denitrifier (3) of the cleaning station, which ensure the movement of the water and sludge mixture throughout the volume of the denitrifier (3) in order to prevent the sedimentation of the silt. The geometry of the denitrifier (3) in the form of a cylindrical circular ring is more optimal than conventional tanks of a different section, as it has a lower hydraulic resistance to the flow of water and sludge, thereby ensuring thorough mixing of water and sludge while reducing the energy consumption required for mixing the conditional volume of the tank, and a possible reduction in the number of mixers (10).

Denitrifier (3) through the through holes is connected to the aeration tank (4). A mixture of water and sludge flows here in a vertical direction through the housings of biological filters, at the bottom of the activation reservoir is oxidized and thoroughly mixed with bubbles of pressure air. The form of oblique inclined surfaces (at an angle of approximately 60 °) of secondary clarifiers (5) is used to create a high-speed activation mixture (water and activated sludge) that occurs when microscopic bubbles collide from the bottom through aerators (11) with external inclined secondary walls septic tanks (5). This ensures that the activation mixture is thoroughly mixed and a homogeneous mixture of sludge and water is formed. This homogeneous mixture, which is a prerequisite for the optimal passage of biological wastewater treatment processes, subsequently passes through the supply pipe (13) in the central distribution pipe (14) located along the axis of the secondary clarifier (5), from which it flows down to the bottom of the settling space . Here there is a separation of the purified water from the heavier particles forming the activated sludge. Then the clarified water flows through the toothed edge of the gutter, which the secondary settling tanks (5) are equipped with in its upper part, into the collection channel, and the water flow is ensured evenly along the entire length of the gutter, and then to the final purification section (9) part of the technological equipment of the station. The compartment (9) of the final water purification may contain drum microsites, microfilters, sand filters, or a combination of these. Excessive sludge from the bottom of the secondary clarifier (5) is pumped out to the central part of the sewage treatment plant for aerobic stabilization of activated sludge, which is equipped with oxidative aerators (11), loses unpleasant odor and reduces its volume by autolysis. When the oxidation process is stopped, stabilized sludge is precipitated and pumped from the bottom with the help of mud tappers to a centrifuge, where the sludge thickens and the silty water returns to the initial stage of the cleaning process through the mechanical separator of large sewage into the selector (2). The dry part of the sludge is collected in containers and exported.

The essence of the invention consists in the layout of the sewage treatment plant, namely in the geometry of its denitrifier (3) and secondary clarifiers (5). The advantage of the cleaning process is the extraction of activated sludge, free from dissolved oxygen, from the bottom of the secondary clarifiers (5) into the denitrifier (3). This sludge suction from the environment with the minimum oxygen content (the bottom of the secondary clarifiers (5)) occurs due to the action of the stirrer (10) in the denitrifier (3). This increases the efficiency of denitrification.

In one activation reservoir there is a combination of two biocultures with different physiological activity. With their rapid growth, biocultures metabolize contaminants in water, and organic contaminants are removed from water. One such bioculture is fixed on the walls of the plastic carrier of biological filters, the other is dispersed in the form of flakes in the active mixture of sludge and water. Thanks to the combination of these biocultures, the cleaning process is accelerated and the sludge concentration in the system increases.

Industrial operational value of the invention: the present invention is intended for wastewater treatment.

The main advantages of the technology:

1. Minimization of the area occupied by the structure due to the compactness of the placement of technological equipment, systems and all technological processes of cleaning in one structure.

2. The area of the sanitary protection zone is limited by the boundaries of the development site.

3. The layout of the station "all in one" - i.e. All technological processes, technological equipment and technological infrastructure are located inside the station, which reduces the cost of earthworks, construction and installation, finishing works, as well as work on the joint installation and connection of technological systems.

4. Zero emission of pollutants and malodorous substances due to the closed layout of the structure.

5. Low energy consumption of the structure relative to the classical layout of the sewage treatment plants at their equivalent capacity.

6. Stability of work with sharp drops in the volumes of effluents and their biological composition.

7. The possibility of launching and stable operation of the station at 10% of the nominal capacity of the structure.

8. Full automation of the cleaning process with the ability to control via GSM or Internet connection.

9. Constant monitoring of the quality of treated wastewaters with the sending of results via GSM or Internet connection.

10. The possibility of reuse of waste

11. The possibility of joint cleaning household - and storm drains on the same structure.

Claims (12)

1. A wastewater treatment plant that contains a vertical cylindrical double-shell activation tank, in the central part of which there are two mutually parallel dividing walls (19), limiting the central part between them for aerobic stabilization of activated sludge and at the same time separating with respect to the inner casing (18) two symmetrically arranged functional spaces for wastewater and purification crops, each of which has a separate chambers (5), tapering downwards, along the axis of each tank (5), there is a hollow cylinder (14) connected both to the inner space of the activation tank using a transverse supply pipe (13) and to the inner space of the secondary sump (5 ), to which the aero tank (4) adjoins on the outside, a perforated compressed air pipeline is laid along the bottom of the activation tank, the central part of the sewage treatment plant is vertically divided into several mutually interconnected through openings of chambers that form a selector (2) connected by its entrance to the outlet of a large sewage separator or by the output of a drum separator located outside the activation tank, and by its output a selector (2) is connected to a denitrifier (3) located between both bodies (17 , 18) of the activation tank, in the partitions of the selector (2) surface (21) and bottom (22) closures are installed, made with the ability to launch and ensure smooth operation of the station with 10% of the effluent from the nominal In the denitrifier (3), there are agitators (10) arranged to ensure the movement of the mixture of waste water and sludge throughout its volume, and the denitrifier (3) is connected with through holes to a part of the activation tank space in the aero tank area (4 ), in which the connection with the secondary settling tank (5) is led by means of a transverse supply pipe (13), while the lower space of the secondary settling tank (5) is connected to the central part of the wastewater treatment plant. 2. The wastewater treatment plant of claim 1, characterized in that the secondary clarifiers (5) have a conical shape with an inclination of the walls of about 60 °. 3. The wastewater treatment plant of claim 1, characterized in that at least one secondary clarifier (5) has a flat bottom, on which are installed buildings with inclined walls in the shape of a body selected from the group comprising a pyramid, a cone, a truncated pyramid and a truncated cone, with the inclined walls inclined at an angle of about 60 °. 4. The wastewater treatment plant of claim 1, characterized in that the lower space of the secondary clarifiers (5) is connected via a regenerator of activated sludge (6) in the central part of the wastewater treatment plant with one of the selector chambers (2). 5. The wastewater treatment plant of claim 1, characterized in that the lower space of the secondary clarifiers (5) is connected to the denitrifier (3). 6. The wastewater treatment plant of claim 1, characterized in that each separately secondary sedimentation tank (5) is provided in the upper part with a waste drain of clarified water. 7. Wastewater treatment plant according to claim 6, characterized in that the drainage chute is connected to the compartment (9) of the final water purification. 8. The wastewater treatment plant of claim 1, characterized in that its walls are made of a material selected from the group consisting of concrete, metal and plastic. 9. The wastewater treatment plant of claim 1, characterized in that it contains an even number of secondary clarifiers (5). 10. Wastewater treatment plant according to claim 1, characterized in that the pipeline of the additional oxidizing system is located at the bottom of the denitrifier (3). 11. The wastewater treatment plant according to claim 1, characterized in that the bottom closures (22) are located at the bottom of the blind separating wall (20). 12. Wastewater treatment plant according to claim 1, characterized in that the selector (2) is made of three stages.

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