Sewage treatment plant and process and floating load

The invention relates to wastewater treatment, namely to the installation and process for wastewater treatment, as well as to floating cargo.

The process and the installation refer to the purification of domestic and industrial wastewater, which contain both suspended matter and organic pollutants, as well as nitrogen and phosphorus compounds. Biologically purified waste water can be used for other purposes, for example for irrigation or for technological purposes. At the same time, the floating load is used to fix the biomass / biofilm in the biological wastewater treatment modules.

A process for biological wastewater treatment is known, carried out with the help of the biological treatment plant, in which wastewater with high concentrations of organic biodegradable pollutants (CBOs) is mixed in an active sludge bioreactor. The obtained mixture comes in contact with dissolved oxygen, which is introduced through an aeration system. This condition favors the growth of sludge flakes, namely biomass particles [1].

The disadvantage of this process is the relatively large volume of the bioreactor. Another disadvantage of the process is that the removal of nitrogen and phosphorus compounds occurs at another stage of treatment, which leads to higher costs for both the investment and the subsequent maintenance of the biological treatment plant.

There is also known a process for biological wastewater treatment, in which the aerobic granular sludge is used, and the biological treatment plant operates a cyclic (discontinuous) type of Sequencing Batch Reactor (SBR) [2].

The disadvantage of this process is that the treatment capacity is considerably reduced at pollutant loads higher than the permissible average. Another disadvantage is that for a higher flow of wastewater more stations are needed, which work in parallel.

Also, a plant and a process of biological purification with the use of active sludge and with bio-discs in a bioreactor are known [3].

The disadvantage of the installation and the process is that the biological treatment bioreactor requires a large volume. Another disadvantage of this installation is the consumption of electricity for the continuous rotation of the biofuels, which leads to the increase of the expenses for the service.

Biofilm fasteners are known, made with free space for biomass / biofilm capture [4].

The disadvantage of the elements is that the free spaces for fixing the biofilm are very small, which leads to their clogging, at the same time, their non-circular shapes make it difficult to mix the elements in the volume of water, which makes it difficult to perform the process of removing the dead biofilm. on the inner surface of the elements.

A fine bubble aeration system is known, which includes aeration elements, installed in a biological module [5].

The disadvantage of this system is that it requires a large number of aeration elements for the biological module, because the range of these elements is very small. If the required number of aeration elements is not installed, some dead zones remain on the interior surface of the biological module, which leads to the reduction of the effluent efficiency.

A lamellar decanter is installed, installed in a vertical cylindrical tank [6].

The disadvantage of this decanter is that, because the blades are obliquely placed against each other, there is a risk of clogging the entire lamellar block, which will lead to the need to periodically remove the lamellar block from the vertical cylindrical tank for washing and, respectively, to interrupt the operation the treatment plant.

Also known is a lamellar decanter, which includes several lamellar blocks of different shapes [7].

The disadvantage of this decanter is the additional costs for the lamellar blocks, which lead to an increase in the price of the treatment plant and the costs of servicing the decanter.

Also, a plant and a process for biological wastewater treatment using suspended biomass (active sludge) are known. The installation includes a waste water inlet pipe, a wastewater mixing tank, submersible pumps for pumping waste water, a biological treatment module, executed as a monobloc tank, which is divided by dividing walls with the formation of an aerobic bioreactor, also includes о

MD 4483 Cl 2017.12.31 waste water drainage pipe. At the top of the system are mounted bars, which are rotated continuously. The role of bars is to fix the biomass. The process is performed with the aid of the described installation and includes the waste water flow in the tank, in which it is homogenized, after which it is cut in the aerobic bioreactor, and in the lamellar decanter the gravitational sedimentation of the sludge from the purified water is performed, then the purified purified water is evacuated through a pipe [8].

The disadvantage of this installation and the process is the recirculation of both the waste water and the active sludge with the help of pumps, which increases the electricity consumption. Rotating the bars also takes place with the help of an electric motor, which also increases the electricity consumption.

It is known о floating load, executed from cylindrical elements for fixing the biofilm, on the surface of which longitudinal grooves are executed [9].

The disadvantage of this load is that the specific surface of the forming and fixing elements of the biofilm is very small, which leads to the need to use a larger number of elements and, respectively, to the о growth of pref. At the same time, the constructive shape of the elements does not allow their protection, as a result, they strike each other and damage them.

The problem solved by the invention is the creation of an installation and a modem process for the purification of domestic and industrial wastewater with a volume of the small biological treatment module and the possibility of carrying out the service works as easily as possible, also of a load. floats used for fixing biomass / biofilm with specific surface area of ​​larger rigid elements at a smaller volume. The purpose of self-cleaning / regeneration / renewal of these elements in the biological purification process is pursued. At the same time, the aim is to obtain a purification system as cheap as possible for implementation. Also, one of the main goals is to reduce the electricity consumption for the subsequent maintenance of the entire treatment plant. The use of rigid elements aims to obtain as much excess sludge as possible, which leads to a reduction in the cost of sludge treatment. At the same time, the direction of the air bubbles, which comes into contact with the water subject to purification, will not be strictly vertical as in the systems of treatment with suspended biomass (active sludge), these hitting the rigid elements will be chaotically directed in different parts of the bioreactors. aerobic, so the contact time with the wastewater and the hybrid microflora (suspended biomass and biomass fixed on the rigid element) will be much longer. This aims to reduce the air flow produced by the air blowers and, respectively, the consumption of electricity. Another purpose is the complete automation of the entire wastewater treatment plant (domestic and industrial), the operator's monitoring time being reduced to only 2 hours a day for the monitoring of the functioning of the entire treatment process, as well as for replacing the sludge dewatering bags. .

The wastewater treatment plant, according to the invention, removes the disadvantages mentioned above by including an automatic mechanical grill, coupled with a waste water inlet pipe and - by a free-drainage pipe with a tank for separating and separating the waste water. greases, equipped with a о float removal valve and joined by a pipe with a waste water mixing tank, which is equipped with a mixer and submersible pumps for pumping waste water through a pipeline in a biological treatment module, executed as a monobloc tank, which is divided by vertically separating bays! in four compartments: an anoxic bioreactor for anoxic reduction of nitrites, an aerobic bioreactor for oxidation of biodegradable organic matter, an aerobic nitrifying bioreactor and a lamellar decanter. Bioreactors are made with the possibility of introducing a floating charge for fixing the biomass. In vertical partitions! the perforations are executed with the possibility of forming a downward-upward flow of waste water from one compartment to another, having the dimensions smaller than the dimensions of the elements of the floating load. The installation also includes an aeration system, which confines air blowers, compressed air pipes and aeration pipes, made of polyethylene, in which perforations are executed and which are located horizontally at the bottom of the aerobic bioreactors. The anoxic bioreactor is equipped with a mixer. An airlift system is installed in an aerobic bioreactor, joined by a water recirculation pipe with the anoxic bioreactor. In the lamellar decanter, a lamellar block is installed with the blades obliquely placed at an angle of 60 ° from the horizontal plane with a distance between them of 10 cm. The lamellar decanter is equipped with a о drainage pipe for purified water and with a о submersible sludge pump, joined by a

MD 4483 Cl 2017.12.31 pipe with a sludge dewatering device in bags, which is joined by a sludge water recirculation pipe with the aerobic bioreactor.

The biological treatment module can have the following dimensions: 4.5 ... 12 m long, 1 ... 3 m wide and 2.5 ... 3 m deep.

The diameter of the perforations in the aeration pipes can be 2 ... 3 mm, and the distance between them - 100 mm.

In the aeration pipes at the extremities can be executed as many as 4 mm in diameter, at the same time they are installed in the aerobic bioreactors at an angle of 3 ° to the outer parts to drain the water from the aeration pipes that came during stopping the supply of compressed air.

The floating load for the wastewater treatment plant, according to the invention, removes the disadvantages mentioned above in that it consists of rigid elements, made of polyethylene with a density of 0.95 g / cm³, each element consisting of an outer ring and an inner ring, which are joined together by eight spifles. On the outer surface of the outer ring are flaps, the ratio between the diameter of the outer ring and the inner one is 3.3 times, and the ratio between the diameter of the outer ring and its width - 2.5 times.

Rigid elemental can have the following dimensions: outer ring diameter - 20 mm, outer ring thickness - 1 mm, inner ring diameter - 6 mm, inner ring thickness - 1 mm, spifle length - 4 mm, spifle thickness - 0.5 mm, height of the fins - 1 mm, the distance between the fins - 0,72 mm and the lower base of the fins - 0,54 mm.

The process of purifying waste water according to the invention removes the disadvantages mentioned above by including the mechanical purification of waste water from suspended materials with dimensions of 2 ... 8 mm with the help of the grate, from which the water flows freely through the pipe in the reservoir, in which the floating matter and the fat, which rises to the surface, is periodically removed through the valve, and the sand particles are sedimented. The mechanically purified water is discharged through the pipeline into the reservoir, where it is homogenized with the aid of the mixer, and then by the pumps it is pumped into the anoxic bioreactor with the floating charge, in which the anoxic reduction process of the nitraxes is carried out by stirring with the help of the mixer. Then the water flows into the first aerobic bioreactor with floating charge, in which the oxidation process of the biodegradable organic matter is carried out, the water being aerated through the aeration pipes with bubbles of 2 ... 3 mm diameter. Then, in the second aerobic bioreactor with floating charge, the nitrification process is carried out with the oxidation of ammoniacal nitrogen, the water being aerated through the bubble aeration pipes with a diameter of 2 ... 3 mm, at the same time, the biomass is fixed in the waste water stream. on the elements of the floating load in bioreactors, the load constituting up to 50% of the volume of each bioreactor. The water containing the nitrites from the second aerobic bioreactor is recirculated through the airlift system into the anoxic bioreactor. In the lamellar decanter, through the lamellar block, gravitational sedimentation of the sludge from the purified water is performed, then the purified purified water is evacuated through the drainage pipe. The sedimentary sludge in the lamellar decanter is pumped with the aid of the pump to the sludge dewatering device, in which the sludge water is recirculated through the pipe in the second aerobic bioreactor and in which the solid phase of the sludge is gravitationally dehydrated up to a maximum humidity of 70 %.

The technical result of the invention consists in reducing the volume of the biological treatment module and eliminating the biodegradable organic substances, nitrogen and phosphorus in a single biological module, as well as increasing the efficiency of biological treatment of the domestic and industrial wastewater by using the hybrid treatment process (suspended biomass). and biomass fixed on the rigid elements), which leads to increased biomass concentration.

The invention removes the disadvantages mentioned by using the biomass / biofilm fasteners, which leads to the decrease of the volume of the biological module, which, in turn, leads to reduced investments. The use of rigid elements leads to the increase of the biomass / biofilm concentration, which allows the process described in the invention to take place in a single biological module with a relatively smaller volume (by about 20 ... 30% compared to the classical treatment with suspended biomass).

The disadvantages mentioned, according to the invention, are eliminated by increasing the specific surface area and the self-cleaning / regeneration / renewal capacity of the biofilm, which leads to the increase of the wastewater treatment efficiency. This invention removes the disadvantages mentioned by using the rigid element, which ensures the fixation of the biomass and, respectively, the formation of the biofilm for the biological treatment of the waste water, which is executed from

MD 4483 Cl 2017.12.31 в

polyethylene, circular in shape, with a density of about 0.95 g / cm³ and is provided with an inner ring and eight spokes. These features allow the rigid elements to float freely in the waste water, but, due to the permanent movement around their axis and their circular shape, they do not allow the adhesion of the biomass / biofilm surplus, being a non-collapsible and self-cleaning environment. The outer ring of the rigid elements is provided with small fine wings, which with the help of air bubbles, obtained from the aeration system with medium bubbles, cause о movement around their axes. Rigid elements can be used for both wastewater treatment at municipal wastewater treatment plants and modular compact wastewater treatment plants.

The advantages of the invention consist in:

a) the advantages of the installation:

- reduced electricity consumption, due to the chaotic movement, and the retention time of the air bubbles in the aerobic bioreactors, which leads to the reduction of the compressed air flow;

- complete automation of the installation;

- reduction of service personnel;

- possibility of treatment of waste water of different types and with different concentrations;

- the small land area on which the plant occupies, due to the decrease of the volume of the biological treatment module;

b) the advantages of the floating load:

- increase of the biomass / biofilm fixing surface up to 900 m²/ m³;

- large free spaces between the edges of the rigid elements, which do not allow their clogging;

- the possibility of adapting the treatment plant to load shocks;

- the possibility of using rigid elements in different bioreactors;

c) the advantages of the procedure:

- significant reduction of the volume of biological treatment plants, due to the increase of the biomass / biofilm concentration through the use of rigid elements;

- reduced production of excess sludge;

- high purification efficiency, without the use of a biopreparative that intensifies the biological processes of biodegradation;

- elimination of suspended matter, organic pollutants, as well as nitrogen and phosphorus compounds through nitrite processes - denitrification;

d) the advantages of the aeration system:

- ensuring a good transfer of oxygen to the water subject to purification;

- more intense mixing / shaking / mixing of the mass of water subjected to purification with rigid elements;

- increase the efficiency of aeration pipes with medium bubbles, due to their manufacture of polyethylene, having a life of approximately 40 years compared to the aeration systems with fine bubbles with rubber membranes, which must be replaced every 2 years;

e) the advantages of the lamellar decanter:

- avoiding clogging, due to the distance between the blades;

- increase the efficiency of water sludge separation by placing the slats (lamellar block) on the entire surface of the lamellar decanter;

- intensification of the process of clearing the waste water purified by the use of blades (lamellar block).

The invention is explained by the drawings in FIG. 1-9, which represents:

FIG. 1, the technological scheme of the biological wastewater treatment process using the rigid elements used in the wastewater treatment plant;

FIG. 2, the wastewater treatment plant, plan view;

FIG. 3, the container with equipment, section view;

FIG. 4, the grease separating and separating tank, coupled with the waste water mixing tank, seen in section;

FIG. 5, the biological wastewater treatment module, which is composed of four compartments;

FIG. 6, elemental rigid, plan view;

FIG. 7, the axonometric view of the rigid element;

FIG. 8, aeration pipes, plan and section view;

FIG. 9, lamellar decanter, section view.

The installation and the process for purifying waste water and the floating load, described in this invention, according to fig. 1-9, include: the equipment container 1, the disintegration tank and

MD 4483 Cl 2017.12.31 grease separation 2, homogenization tank 3 of waste water, anoxic bioreactor 4, aerobic bioreactor 5, aerobic bioreactor 6 and lamellar decanter 7.

Container 1 (Figs. 2 and 3) confines the waste water inlet pipe 1.1 under pressure, the automatic mechanical grill 1.2, the free-flowing pipe 1.3, the air blowers 1.4, the compressed air pipes 1.5, the sludge dewatering device in the bags 1.6 , recirculation pipe 1.7 of the sludge water.

The grease separating and separating tank 2 (Figs. 2 and 4) confines the valve for the removal of floating materials 2.1 and the pipe 2.2.

The homogenization tank 3 of the waste water (Figs. 2 and 4) confines the mixer 3.1, the submersible pumps 3.2 for supplying the biological treatment module, the pipe 3.3 of mechanically purified waste water and the flow meter 3.4.

The anoxic bioreactor 4 (Figs. 2 and 5) confines the mixer 4.1 and the floating charge 4.2 for fixing the biomass / biofilm.

The aerobic bioreactor 5 (Figs. 2 and 5) confines the aeration pipes 5.1 with medium bubbles and the floating charge 4.2 for fixing the biomass / biofilm.

The aerobic bioreactor 6 (Figs. 2 and 5) confines the aeration pipes 6.1 with medium bubbles, the airlift system 6.2, the recirculation pipe 6.3 of the water, the floating charge 4.2 for fixing the biomass / biofilm.

Lamellar decanter 7 (figs. 2, 5 and 9) confines the submersible sludge pump 7.1, the sludge pipe 7.2, the lamellar block 7.3, the drainage pipe 7.4 of the purified wastewater.

The floating load 4.2 for fixing the biomass / biofilm consists of rigid elements (Figs. 5, 6 and 7), which include the outer ring 4.2.1 and the inner ring 4.2.2, which are joined together by eight spades 4.2.3. , and on the surface of the outer ring 4.2.1 the wings 4.2.4 are executed.

5.1 medium bubble aeration pipes (Figs. 2, 5 and 8) contain 5.1.1 perforations for aeration with a diameter of 2 ... 3 mm and 5.1.2 perforations for water drainage from aeration pipes 5.1.

The lamellar block 7.3 (Figs. 7 and 9) includes the oblique slides 7.3.1.

According to the invention, the purification of domestic and industrial wastewater takes place with the help of the hybrid process, ie with both suspended biomass (active sludge) and with biomass / biofilm, which grows on rigid elements, constantly moving. Biological treatment takes place in four compartments: anoxic bioreactor 4, aerobic bioreactor 5, aerobic bioreactor 6 and lamellar decanter 7. In the first three compartments, rigid elements for fixing the biomass / biofilm by volume up to 50% of the volume of the bioreactors are introduced. The passage of waste water from one compartment to another occurs in a downward-upward vertical flow. In the fourth compartment (lamellar decanter 7) the sludge is separated from the waste water purified by sedimentation and pumped by means of a submersible sludge pump 7.1 to the sludge dewatering device in bags 1.6.

The biological treatment module occupies a small space, at the same time it has maximum efficiency, and the treatment process is simple, efficient and with minimal operating costs. The purification process, being automated, excludes the permanent supervision of the operator. The biological treatment process has a rapid onset. The installation will reach in maximum 4 ... 6 weeks at optimum operating conditions, even in case of longer interruptions of supply of waste water.

According to the invention, in the treatment plant, the waste water from the pumping pipe, separated from the suspended materials with dimensions larger than 8 mm by means of a coarse grill, enters through the waste water inlet pipe 1.1 under pressure in the automatic mechanical grill 1.2, where the mechanical purification takes place. In this are suspended materials with dimensions ranging from 2.0 to 8.0 mm. From the grid 1.2 the water passes gravitationally through the pipe 1.3 with a free flow directly into the tank for separating and separating the fats 2, where the floating matter rises to the surface and is removed periodically manually with the opening of a valve for removing the floating material 2.1, at the same time the particles of sand is sedimented, and the mechanically purified water of fats and floating materials through pipe 2.2 passes into the mixing tank 3. For mixing the flows and concentrations of the wastewater and for excluding sedimentation in the mixing tank 3, the mixer 3.1 is provided. From the homogenization tank 3 by means of submersible pumps 3.2 mechanically purified water is pumped through pipeline 3.3 to the biological module, which confines four compartments: the anoxic bioreactor 4, the aerobic bioreactor 5, the aerobic bioreactor 6, the lamellar decanter 7. For measuring the waste water flow, which enters the biological module through pipe 3.3, the flow meter 3.4 is installed on it.

MD 4483 Cl 2017.12.31

The division of the compartments in the biological module takes place through the vertical partition walls. Because the passage of water from one compartment to another is in a downward vertical flow, some walls are perforated at the bottom, and alfalfa - at the top. In order to prevent the passage of the rigid elements 4.2 from one compartment the diameter of the perforations is smaller than the diameter of the rigid elements 4.2. In the biological module compartments biological wastewater treatment takes place. The biological module is made up of 4 compartments for increased purification efficiency: compartment 1 - anoxic bioreactor 4 (denitrification / reduction of nitrates); compartment 2 - aerobic bioreactor 5 (CBO elimination); compartment 3 - aerobic bioreactor 6 (nitrification with ammoniacal nitrogen oxidation); compartment 4 - lamellar decanter 7 (sludge separation from purified wastewater).

The mechanically purified waste water is introduced into the biological module through pipeline 3.3, starting with the anoxic bioreactor 4. It confines the rigid elements 4.2, but, being not aerated, it achieves the anoxic reduction of the nitrites (denitrification) by stirring with the help of the mixer 4.1.

The aerobic bioreactor 5 confines the rigid elements 4.2, but is aerated with medium bubbles with a diameter of 2 ... 3 mm, using the aeration pipes 5.1. This is where the oxidation of the biodegradable organic matter takes place and, respectively, the elimination of the CBO.

Aerobic bioreactor 6 confines rigid elements 4.2 and is aerated with medium bubbles of 2 ... 3 mm diameter, using aeration pipes 6.1. Here complex phenomena of nitrification occur, which lead to the oxidation of ammoniacal nitrogen. Also, in the aerobic bioreactor 6, an airlift system 6.2 is installed, which recirculates the water with the content of naphras from the aerobic bioreactor 6 into the anoxic bioreactor 4 through the recirculated water pipe 6.3.

In lamellar decanter 7, which confines lamellar block 7.3, the sludge is separated from the waste water purified by gravitational sedimentation. The purified, clarified waste water is discharged from the biological module through the exhaust pipe 7.4 of the purified waste water.

After the biological module the water is disinfected, then directed to the emitter.

Separated (sedimented) sludge in lamellar decanter 7 is pumped with the help of submersible sludge pump 7.1 to the sludge dewatering device in bags 1.6. Pump

7.1 shall be automatically included at time intervals established by the control panel depending on the concentrations of the waste water and the volume of the sedimented sludge, respectively. In these bags dewatering sludge occurs. The device 1.6 consists of a dispenser with faucets and a metal frame and bags for filtering and refining the sludge. The sludge, pumped into these bags through the sludge pipe 7.2, is sedimented and gravitationally dehydrated. The sludge is refined in sacks and the sludge water is re-introduced into the aerobic bioreactor 6 through pipe 1.7. The moisture of the sludge after dehydration in the bags is about 70%. After filtering the bags can be stored on a bag storage platform, remove from the reed, stored in an open area or stored for use in agriculture.

The lamellar block 7.3 which is installed inside the lamellar decanter 7 is made of the slabs placed obliquely 7.3.1 at an angle of 60 °. The distance between them is 10 cm. These things produce much greater efficiency than the conventional decanters, which leads to a much smaller reduction in the volume of the entire decanter 7.

The aeration system confines the air blowers 1.4, the compressed air pipes 1.5 and the aeration pipes 5.1 with medium bubbles, made of polyethylene beams, which confers in the perforations.

5.1.1 for aeration with a diameter of 2 ... 3 mm and a distance between them of 100 mm. Through these perforations the compressed air coming from the air blowers 1.4 is distributed mass of water with the rigid elements 4.2. In case of stopping the supply of compressed air to the 5.1 pipes, they are filled with water, so for the elimination of the water from them, at the bottom of them, the perforation 5.1.2 of the evacuation of the water from the 5.1 ventilation pipes is expected with diameter of 4 mm. To remove the water from the 5.1 pipes as soon as possible, they are inclined at an angle of 3 ° to the outer parts. The 5.1 pipes are supplied with compressed air from the air blowers 1.4 through the compressed air pipes 1.5.

Rigid elements 4.2 are made of polyethylene and serve to fix the biomass / biofilm, in addition to the suspended biomass flakes (active sludge). These rigid elements 4.2 are cylindrical in shape and border the outer ring 4.2.1, the inner ring 4.2.2 and eight spades 4.2.3, which unite them, and on the outer surface of the outer ring 4.2.1 the wings are made 4.2.4. Rigid elements 4.2 occupy about 50% of the total volume of bioreactors 4, 5 and 6. In bioreactors 4, 5 and 6 wastewater meets rigid elements 4.2, which form a common mass. This mass (the rigid elements and the waste water) is aerated intensively with compressed air by means of the pipes 5.1. Air propelled from pipes 5.1

MD 4483 Cl 2017.12.31 produces the permanent rotation of the rigid elements 4.2, which, in turn, leads to the fixation of the biomass and, respectively, to the formation of the biofilm on the surface and inside the elements 4.2. The outer surface of the elements 4.2 is equipped with small wings 4.2.4, which with the help of the air bubbles from the pipes 5.1, cause о movement around their axis. The ratio 5 between the outer ring diameter 4.2.1 and the inner ring 4.2.2 is 3.3, and the ratio between the outer ring diameter 4.2.1 and its width - 2.5. The specific surface area of ​​the rigid elements 4.2 is approximately 900 m²/ m³. The density of the elements 4.2 is 0.95 g / cm³, which allows them to float freely in the water.

(56) Bibliographic references cited in the description:

1. US 3864246 TO 1975.02.04

2. US 20030159991 To 2003.08.28

3. US 2007023356 To 2007.02.01

4. US 4122011 TO 1978.10.24

5. US 5266239 TO 1993.11.30

6. EP 1745832 to 2007.01.24

7. EP 0973595 To 2000.01.26

8. US 2005247623 to 2005.11.10

9. US 8241717 Bl 2012.08.14 (57) Claims: