RU2547734C2 - Method of purifying household and industrial sewage water - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to purification of household and industrial sewage water. The method of sewage water purification includes balancing a water flow and biological purification with active sludge. Initial sewage water is supplied through a self-cleaning filter device for straining, and mechanically purified sewage water is discharged into a balance tank and supplied into a tank of biological purification. Separation of purified water and active sludge is carried out by means of submergible membrane cassettes with membrane modules. Separation of permeate is realised by the action of a weak vacuum. Permeate is supplied into a pure water tank and further by a gravity flow to an installation of ultraviolet disinfection. Disinfected water is discharged into a water body. Continuous aeration of the membrane cassettes with membrane modules is realised by means of a group of membrane unit blast blowers. The membrane modules are periodically washed and alternated with relaxation modes. Also realised is the periodic prophylactic cleaning of the membrane cassettes and periodic restoring cleaning.

EFFECT: invention makes it possible to improve the quality of purified water discharges and provide the relaxation of applied devices.

2 dwg

Description

The invention relates to a method for purifying industrial water effluents and relaxing devices for reuse.

Known analogues include inventions:

1. AC 1710525 to the application 4382354 from 02.24.1988, publ. 02/07/1992, MKI C02F 3/02, C02F 3/10.

2. RF patent No. 2225367, IPC C02F 3/30; C02F 101: 16, C02F 101: 30 dated 12.20.2002.

3. AC 785225, IPC C02F 3/12, publ. 12/07/1980.

The mentioned inventions require improvement, to which a new technical solution is directed, which contributes to the quality of industrial wastewater treatment and the reliability of the devices used.

The task of cleaning household wastes and industrial wastewater and relaxation of the devices used is achieved based on the study of analogues (1-3) and is aimed at the possibility of improving the quality of treated industrial wastewater and device relaxation in a new way.

A method of treating domestic and industrial wastewater, which consists in averaging the water flow using a hydraulic mixing system, including a pump and pipelines, and in subsequent biological treatment with activated sludge, including denitrification in the anoxide zone and aerobic treatment, in containers separated by a partition, using filtering membrane modules consisting of hollow fiber polymer elements, a vacuum pump manifold, a backwash pump that supplies purified water, to an air blower ki with pipelines, characterized in that the source wastewater is fed through a pressure pipe through a self-cleaning filtering device for filtering through a grid of armamide, consisting of fibers with a profile and 2 mm spacing, and mechanically treated wastewater is drained into a homogenizing tank with subsequent supply pumps into the biological treatment tank, the latter containing at least one parallel line, consisting of a denitrifier, in which free nitrogen is released, and an aeration tank-nitrifier a, the latter being equipped with a fine-bubble aeration system supporting the concentration of dissolved oxygen within 2-3 mg / l, with the release of free nitrogen, using submersible membrane cassettes with membrane modules, phase separation of purified water and activated sludge is carried out through the use of hollow fiber membranes with polyvinylidene fluoroid composition with membrane pores of 0.04-0.2 microns, where the permeate is separated by the action of a weak vacuum formed in a vacuum manifold - the suction pipe of a centrifugal a water pump, at a given capacity, regulated by frequency converters, and permeate is fed into a clean water tank and then by gravity to an ultraviolet disinfection unit, after which disinfected water is discharged into a water object, and continuous aeration of membrane cassettes with membrane modules is carried out using a separate group of membrane blowers block, and for periodic washing of the membrane modules, use a backwash pump, while the backwash of the membranes alternate with the modes relaxation, stopping the selection of permeate by turning off the permeate pump without turning on the backwash pump, with an activated sludge submersible pump, which ensures denitrification and uniformity of activated sludge inside the unit, and a solution of ferric chloride for reactive removal of phosphorus is fed into the circulating activated sludge pump by a metering pump, at the same time along with air cleaning and backwashing of the membrane modules, periodic preventative cleaning with backwashing with sodium hypochlorite and lemon acid, using metering pumps and solutions of sodium hypochlorite or citric acid, which is carried out without removing the membrane modules from the membrane tank, along with air cleaning, backwashing and preventive cleaning of the membrane modules with the accumulation of organic and mineral contaminants in the pores of the membranes, provide for periodic reconditioning consisting in the soaking of the membrane cassettes in solutions of sodium hypochlorite and citric acid, which is carried out by a metering pump, a solution of hypochlor ita or citric acid, without removing the membrane modules from the membrane tank, no more than 1-2 times a year during the period of minimal wastewater inflow by using the volume of the averager, while the treatment facilities include a technological pavilion with pumps, metering pumps located in it , two groups of blower units, a reagent farm, an ultraviolet disinfection unit, a sludge disinfection unit with bag filters or centrifuges.

Graphic Images: FIG. 1 is a serial input circuit of industrial wastewater treatment devices; FIG. 2 - positions of relaxation recovery.

The list of items shown in FIG. 1 and FIG. 2: wastewater (1); pressure pipe (2); self cleaning filtering device (3); mesh of armamide (4); averaging tank (5); pumps (6-8); biological treatment tank (9); denitrifier (10); aerotank nitrification (11); fine bubble aeration system (12); organic matter (13); oximeter (14); bioreactor blower (15); frequency converter (16); silt mixture (17); stirrer (18); gyrator (19); activated sludge (20); immersion membrane cartridge (22); membrane module (23); purified water (24); metering pump (25); hollow fiber polyvinylidene fluoroid composition (26); permeate (27); low vacuum (28); suction pipe (29); centrifugal permeate pump (30); backwash pump (31); membrane pores (32) are not shown; pure water tank (33); ultraviolet disinfection unit (34); disinfected wastewater (35); vehicle tank (36) - not shown; water body (37); sludge dewatering unit (38); backwash pump (39); ferric chloride solution (40) - reagent; fencing of the technological pavilion (41) - not shown; technological pavilion (42); bag filter (43); blower station (44); belt filter (45) - not shown; group of aggregates (46); sodium hypochlorite (47) - reagent; citric acid (48) - reagent; press (49) - not shown; centrifuge (50) - not shown; thickener drum (51) - not shown.

Description of the method.

A method of treating domestic and industrial wastewater, which consists in averaging the water flow using a hydraulic mixing system, including a pump and pipelines, and in subsequent biological treatment with activated sludge, including denitrification in the anoxide zone and aerobic treatment, in containers separated by a partition, using filtering membrane modules consisting of hollow fiber polymer elements, a vacuum pump manifold, a backwash pump that supplies purified water, to an air blower ki with pipes, characterized in that:

 - the initial volume of domestic and industrial wastewater (1) with relaxation of the devices used is fed through the pressure pipe (2) through the cleaning filter device (3);

- after filtering through a grid of armamide (4) or other special material consisting of fibers of oil products with a profile and 2 mm spacing;

- mechanically treated domestic and industrial wastewater (1) is discharged into the averaging tank (5) for subsequent supply of wastewater with pumps (6-8) to the biological treatment tank (9) of a portion volume of domestic and industrial wastewater (1) );

- the biological treatment tank (9) contains at least one parallel line consisting of a denitrifier (10) and an aeration tank-nitrifier (11), where the latter is equipped with a fine-bubble aeration system (12) that maintains the concentration of dissolved oxygen in the range of 2-3 mg / l, contributing to the oxidation of organic substances (13) and their nitrification at a given concentration of dissolved oxygen, regulated by an oximeter (14) and differentiating the bioreactor blower working process (15) using a frequency converter (16);

- to prevent sedimentation of the sludge mixture (17), a mixer (18) or a gyrator (19) is installed in the denitrifier (10);

- the process is accompanied by oxidation of activated sludge (20), under anoxic conditions, with the release of free nitrogen;

- in the nitrifier (11), using immersion membrane cartridges (22), with membrane modules (23), phase separation of purified water (24) and activated sludge (20) is carried out through the use of hollow fiber polyvinylidene fluoroid compositions (26) with membrane pores in 0.04-0.2 μm, where the permeate (27) is separated by the action of a weak vacuum (28) formed by the suction pipe (29) of a centrifugal permeate pump (30) at a given capacity, regulated by a frequency converter (16), and the dose of activated sludge (20) in a membrane bioreactor - (MB P) support within 4-10 g / l in proportion to the composition of domestic and industrial wastewater, and permeate (27) is fed into a clean water tank (33), from where the latter flows by gravity into the ultraviolet disinfection unit (34);

- disinfected wastewater (35) is diverted to the tank of the vehicle (36) or to a water body (37), and for washing the membranes (22) use a backwash pump (31), which alternate with the relaxation mode, stop the selection of permeate (27) without turning on the backwash pump (39), which reduces energy consumption and increases the number of periods between backwashes;

- the fraction of activated sludge (20) is pumped from the end of the nitrification unit (11) to the denitrifier (10) with a submersible circulation pump (39) and, due to recirculation, provide denitrification and uniformity of activated sludge (20) inside the unit;

- in a stream of circulating activated sludge (20), a metering pump (25) serves a solution of ferric chloride (40) for the reagent removal of phosphorus by a metering pump (25);

- treatment facilities include a technological pavilion (42), with pumps (6-8, 30, 31) located in it, a reagent farm (40, 47, 48), a sludge dewatering unit (38) with bag filters (43), thickener drums, belt filters, presses or centrifuges, a blower station (44) with two groups of units (15 and 46);

- the first group of units (15) consists of blowers and supplies air to nitrification aeration tanks (11), and the second group of units (46) is used to supply air under membrane cartridges and to mix household and industrial wastewater (1) in the tank -redifier (5);

- air cleaning and backwashing are used to maintain membrane permeability, where prophylactic cleaning along with a backwash sequence with sodium hypochlorite (47) or citric acid (48) is provided;

- preventive cleaning of the membranes (22) is carried out without removing them from the nitrotifier aeration tank (11);

- the frequency of preventive treatment depends on the specifics of the facility and the quality of incoming domestic and industrial wastewater (1) from 1-2 times per week;

- fouling of membranes (22) occurs as a result of the accumulation of organic substances or crystallization of salts in the pores of membrane fibers, which require re-cleaning of the membranes (22) from 1-2 times a year, which involves soaking the membranes (22) in solutions of the same reagents (47, 48) for several hours during the minimum inflow of domestic and industrial wastewater (1) through the use of the volume of the averager (5).

An example of the method.

A method of treating domestic and industrial wastewater, which consists in averaging the water flow using a hydraulic mixing system, including a pump and pipelines, and in subsequent biological treatment with activated sludge, including denitrification in the anoxide zone and aerobic treatment, in containers separated by a partition, using filtering membrane modules consisting of hollow fiber polymer elements, a vacuum pump manifold, a backwash pump that supplies purified water, to an air blower ki with pipelines operate such that:

1. The initial volume of domestic and industrial water effluents (1) is fed through a pressure pipe (2) through the filtering device itself (3), and after filtering through a mesh of armamide (4) or other special material consisting of fibers of oil products with with a profile and 2 mm openings, mechanically treated domestic and industrial wastewater (1) is poured into the averaging tank (5) for subsequent supply of wastewater with pumps (6-8) to the biological treatment tank (9) of a portion volume of household and traded venous wastewater (1);

2. biological treatment tank (9) contains at least one parallel line consisting of a denitrifier (10) and an aeration tank-nitrifier (11), where the latter is equipped with a fine-bubble aeration system (12) that maintains the concentration of dissolved oxygen in the range of 2-3 mg / l, which contributes to the oxidation of organic substances (13) and their nitrification at a given concentration of dissolved oxygen, regulated by an oximeter (14) and differentiating the bioreactor blower working process (15) using a frequency converter (16);

3. to prevent sedimentation of the sludge mixture (17) in the denitrifier (10), a mixer (18) or a gyrator (19) is installed;

4. the process is accompanied by oxidation of activated sludge (20), under anoxic conditions, with the release of free nitrogen;

5. in the nitrifier (11), using immersion membrane cartridges (22), with membrane modules (23), phase separation of purified water (24) and activated sludge (20) is carried out by using hollow fiber polyvinylidene fluoroid compounds (26) with membrane pores in 0.04-0.2 μm, where the permeate is separated (27), it is carried out by the action of a weak vacuum (28) formed by the suction pipe (29) of a centrifugal permeate pump (30) at a given capacity controlled by a frequency converter (16);

6. The dose of activated sludge (20) in the membrane bioreactor - (ICBM) is maintained within 4-10 g / l in proportion to the composition of domestic and industrial wastewater;

7. permeate (27) is fed into a clean water tank (33), from where the latter flows by gravity into the ultraviolet disinfection unit (34);

8. disinfected wastewater (35) is discharged into the tank of the vehicle (36) or into a water body (37);

9. For washing the membranes (22), use a backwash pump (31), which is alternated with a relaxation mode, stop permeate selection (27), without turning on the backwash pump (39), which reduces energy consumption and increases the number of periods between backwashes;

10. a fraction of activated sludge (20) is pumped from the end of the nitrifier (11) to the denitrifier (10) with an immersion circulation pump (39) and, due to recirculation, provide denitrification and uniformity of activated sludge (20) inside the unit;

11. in the flow of circulating activated sludge (20) with a metering pump (25) serves a solution of ferric chloride (40) for the reagent removal of phosphorus by a metering pump (25);

12. treatment facilities include a technological pavilion (42), with pumps (6-8, 30, 31) located in it, a reagent farm (40, 47, 48), a sludge dewatering unit (38) with bag filters (43) , by drums, thickeners, belt filters, presses or centrifuges, a blower station (44) with two groups of units (15 and 46);

13. The first group of units (15) consists of blowers and supplies air to the nitrification aeration tanks (11);

14. the second group of units (46) is used to supply air under the membrane cassettes and for mixing household and industrial wastewater (1) in the averaging tank (5);

15. air cleaning and backwashing are used to maintain membrane permeability, where prophylactic cleaning along with a backwash sequence with sodium hypochlorite (47) or citric acid (48) is also provided;

16. prophylactic cleaning of the membranes (22) is carried out without removing them from the nitrotifier aeration tank (11);

17. The frequency of preventive treatment depends on the specifics of the facility and the quality of incoming domestic and industrial wastewater (1) from 1-2 times a week;

18. fouling of membranes (22) occurs as a result of the accumulation of organic substances or crystallization of salts in the pores of membrane fibers, which require re-cleaning of the membranes (22) 1-2 times a year, which involves soaking the membranes (22) in solutions of the same reagents (47 .48) for several hours during the minimum inflow of domestic and industrial wastewater (1) through the use of the volume of the averager (5).

Industrial novelty of a technical solution.

The study of the method was carried out in real conditions of an industrial enterprise, which is important from the point of view of practical implementation and evidence of opportunities to improve the quality of treated wastewater in a volume of 30-100000 m ³ / day.

The economic efficiency of the method is justified by the direct use of the method for cleaning household wastes and industrial effluents for multiple processes of restoration of devices used in the practical use of relaxation periods of the pores of membrane fibers in the conditions of oil refineries, refineries, refineries, oil and gas research institutes and VODGEO.

As a result of domestic and industrial wastewater treatment, the following indicators were obtained: BOD and suspended solids <3 mg / l; ammonium nitrogen <0.39 mg / l; nitrate nitrogen <9 mg / l; nitride nitrogen <0.02 mg / L; phosphorus phosphorus <0.2 mg / L; petroleum products <0.05 mg / l; SAS <0.1 mg / L.

Claims (1)

A method of treating domestic and industrial wastewater, which consists in averaging the water flow using a hydraulic mixing system, including a pump and pipelines, and in subsequent biological treatment with activated sludge, including denitrification in the anoxide zone and aerobic treatment in containers separated by a partition, with using filtering membrane modules consisting of hollow fiber polymer elements, a vacuum manifold pump, a backwash pump that supplies purified water, air blowers with pipelines, characterized in that the source wastewater is fed through a pressure pipe through a self-cleaning filtering device for filtering through an armamide mesh consisting of fibers with a profile and 2 mm openings, and mechanically treated wastewater is poured into the averaging tank with subsequent supply pumps into the biological treatment tank, while the latter contains at least one parallel line consisting of a denitrifier, in which free nitrogen is released, and a nitrification aeration tank ora, the latter being equipped with a fine-bubble aeration system that maintains a concentration of dissolved oxygen in the range of 2-3 mg / l, with the release of free nitrogen, using phase-immersion membrane cassettes with membrane modules, phase separation of purified water and activated sludge is carried out by using hollow fiber membranes with polyvinylidene fluoroid composition with membrane pores of 0.04-0.2 μm, where the permeate is separated by the action of a weak vacuum formed in a vacuum manifold - a suction pipe of a centrifugal at a given capacity, controlled by frequency converters, the permeate is fed into a clean water tank and then by gravity to an ultraviolet disinfection unit, after which disinfected water is discharged into a water body, and continuous aeration of membrane cassettes with membrane modules is carried out using a separate group of membrane blowers unit, and for the periodic washing of the membrane modules using a backwash pump, while the backwash of the membranes alternate with the modes and relaxation, stopping the selection of permeate by turning off the permeate pump without turning on the backwash pump, with an activated sludge submersible pump, which ensures denitrification and uniformity of activated sludge inside the unit, and a solution of ferric chloride for reactive removal of phosphorus is fed into the circulating activated sludge pump by a metering pump, at the same time, along with air cleaning and backwashing of the membrane modules, periodic preventive cleaning with backwashing with sodium hypochlorite and lemon is provided acid, using metering pumps and solutions of sodium hypochlorite or citric acid, which is carried out without removing the membrane modules from the membrane tank, along with air cleaning, backwashing and prophylactic cleaning of the membrane modules with the accumulation of organic and mineral contaminants in the pores of the membranes, provide periodic reconditioning consisting in the soaking of the membrane cassettes in solutions of sodium hypochlorite and citric acid, which is carried out by a metering pump, a solution of hypochl reagent or citric acid, without removing the membrane modules from the membrane tank, not more than 1-2 times a year during the period of minimal wastewater inflow by using the volume of the averager, while the treatment facilities include a technological pavilion with pumps, metering pumps located in it , two groups of blower units, a reagent farm, an ultraviolet disinfection unit, a sludge disinfection unit with bag filters or centrifuges.

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