SU1576492A1 - Device for purifying waste water with active silt - Google Patents

Abstract

This invention relates to the biological treatment of municipal and industrial wastewater. The purpose of the invention is to increase the efficiency of the cleaning process under the conditions of fluctuations in the inflow, composition and temperature of wastewater. The device comprises an aerotank case 1, divided by partitions 3, 4 into direct, reverse mixing corridors 5, 8, as well as pressure corridor 11 and regenerator 12. The aerotank is equipped with dispersants 13, speed regulators 44, 47 and thermometers 48, 49. During the period of small inflow of sewage, the liquid being cleaned through channel 15 through measuring tray 18 enters mixing corridor 5, aerates and flows into displacement corridor 11 and is removed from installation through channel 16. The device is designed for increased inflow of waste water and Lebani temperatures between 22 - 23 and 25 - 30 ° C. The invention allows to reduce energy and capital costs. 3 hp f-ly, 3 ill.

Description

The invention relates to the biological treatment of municipal and industrial wastewater.

The aim of the invention is to increase the efficiency of the cleaning process in the conditions of fluctuations in the inflow, composition and temperature of the wastewater.

Fig, 1 shows the device. Plan; FIG. 2 is a section A-A in FIG. one; in fig, 3 is multilayer on-- cage.

The device includes a body 1 of the aerofoil 2, divided by longitudinal and transverse partitions 3 and 4 into a forward mixing corridor 5 e with initial and final compartments 6 and 7, a reverse mixing corridor 8 with initial and final compartments 9 and 10, a push corridor 1 and a regenerator 12 AeroTekk is equipped with fine-bubbling dispersers of constant action 13, attached to the air ™. the heater 14, channels 35, 16 and 1 of the original, treated wastewater and return activated sludge,

A distribution and control channel 19, divided by a transverse overflow partition 20 on a small flow tray 21 and a tray 22 with bottom openings 23 of increased flow, is connected to the channel 15 of the original waste water supplied with the measuring tray 18. Forward and reverse mixing lanes are communicated by means of an overflow pipe 24 and a gate 25.

The recirculation unit 26 consists of an air contact 27 and a submersible axial pump 28 with an electric motor 29 connected by a recirculation pipe 30. The air contact is made with a multi-layer nozzle 31 in the form of inclined slats 32 with layers 33 of longitudinal orientation of the slats and layers 34 of transverse orientation of the slats, Kor5

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The aero contactors 35 in the upper part 36 is equipped with a diffuser 37, in the center of which an axial fan 38 is installed with an electric motor 39. A distribution tray 40 of sludge medium with triangular weirs 41 attached to the upper part 42 of the recirculation pipeline is mounted to the lower part of which is attached submersible axial pump.

The motor of the submersible pump is equipped with an automatic speed controller 44, to which a level gauge 45 is connected according to a direct communication scheme, and a dissolved oxygen analyzer 46 is connected according to a feedback scheme. The axial-flow fan motor is equipped with an automatic regulator 47. the number of revolutions to which an electrical contact thermometer 48 attached to the measuring tray is connected according to a direct communication circuit and a electrical contact thermometer 49 mounted in the aerotank mixing corridor 49 is connected to the feedback circuit.

The device works as follows.

During the period of small inflow of sewage, when their temperature does not exceed the established limits, for example, 20 ° C, the waste water, after passing the measuring tray 38, enters the direct mixing corridor 5 of the aerotank 2 through the tray 25 of the small inflow of the distribution and regulating channel 19. Driving In the forward mixing corridor 5, the waste liquid mixed with activated sludge is aerated with compressed air entering through fine-bubble dispersers 13 of constant action, as a result of which the main stage of its biological purification is carried out. Further, when the gate is closed, 25 the medium enters vyves5-15764

corridor 11, where, under conditions that prevent unoxidized organic pollutants from escaping, biological treatment of the waste is completed

water, and it enters channel 16 of the treated wastewater. Returnable sludge from the secondary settling tank through channel 1 of the returnable sludge enters the regenerator 12, where it is aerated for a certain time to restore its original activity, and then fed into the back mixing corridor 8. During periods of low flow, the reverse mixing corridor 8 serves as a storage tank. regenerated activated sludge, the return part of which through the bypass outlet 24 is constantly poured into the initial compartment 6 of the direct mixing corridor 5 for the implementation of biological tion of wastewater treatment,

During periods of low sewage inflow, active sludge concentration is set in the regenerator 12 and the reverse mixing corridor 8 of the aerotank in the order of 6-8 g / l, and in the forward mixing corridor 5 and the displacement corridor 11, after mixing with the incoming waste water, the active sludge maintained at 1.5-2 g / l.

During periods of increased inflow of sewage, when the specific load on the aeration tank for organic pollutants m increases by 2.5–3 times as compared with the initial one, and the temperature of wastewater somewhat exceeds the established limits and is, for example, 22-23 ° C, a part of the waste water is first poured over the transverse overflow partition 20 into the tray 22 of the increased inflow, through the bottom openings 23 of which enters the final compartment 10 of the reverse mixing corridor 8. During this period of operation, the submersible motor 29 is turned on. The axial pump 28, as a result of which the recirculation pipeline 30 to the distributor tray 40 of the sludge medium located in the upper part of the aerocontactor 27 and equipped with triangular spillways 41, begins to flow recirculation sludge medium with the concentration of active sludge 6 -8 g / l. At the same time, the result of opening the gate 25 from the forward mixing corridor 5 to the reverse mixer

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The corridor 8, connected according to the law of communicating vessels, begins to receive a consumption of sludge medium equal to the recirculation one, with a concentration of active sludge of 1.5–2 g / l. The pre-oxygenated supply of a part of the incoming sewage - silt medium, overflowing through the triangular weirs 41 of the distributor tray 40 of the sludge medium, falls into the multilayer nozzle 31 of the aerocontactor 27 in the form of inclined slats 32, is crushed into small trickles and drops, then flows into the initial compartment 6 straight mixing corridor 5, adjacent to the tray 21 small inflow. In the process of crushing the sludge medium about the multilayer nozzle 31 and its movement, an effective gas-liquid contact occurs in the aero-contact 27, as a result of which the sludge medium is saturated with dissolved oxygen, and at the same time its temperature decreases to the established limits due to the outdoor temperature and partial evaporation fluid. i

During this period of work in the forward and reverse mixing corridors 5, 8, as well as in the displacement corridor 11 of the aerotank, as a result of mutual averaging, the concentration of active sludge is set at 3.7–5 g / l, which, given the increase in the amount of organic matter entering 2.5-3 times it allows to maintain the specific load on activated sludge at a constant level and for the given type of wastewater at an optimal level. The recirculation flow of the sludge medium pumped through the aerocontactor 27, which carries an additional amount of dissolved oxygen, ensures uniform distribution of organic pollutants in the entire volume of the aerotank as a result of the transformation of its hydrodynamic regime from displacement to mixing, as well as providing stabilization of the temperature regime defined It is a special calculation, which shows that the recirculation flow rate of the sludge medium exceeds the flow rate of the incoming sewage by 3-7 times.

During the period of increased inflow of sewage, when their temperature significantly exceeds the established limits and is equal, for example, 25-30 С „the cooling effect of the aerocontactor

27 may be insufficient for temperature stabilization: the working medium of the aerotank is at a given level. This reduces the solubility of oxygen in the sludge medium, and may also cause deterioration in the sedimentary properties of the activated sludge. In order to avoid this, in addition to the described technological operations, an axial fan 38 is installed, installed in the upper part 36 of the housing 35 of the aero-contact 27. At the same time, through the multilayer nozzle 31, irrigated with sludge medium, rush out air flows that stabilize the temperature of the working medium in the aero ™ and increase the oxidizing effect of the aerocontactor.

Both the oxidizing and temperature effects of the aerocontactor are determined by how evenly the recirculation flow of the sludge medium is distributed in its cross section. For this, a jet of sludge medium from triangular spillways 41 of a tray-distributor 40 of sludge medium falls onto a multi-layer nozzle 31, the longitudinal axes ppek 32 of adjacent layers of which are perpendicular to each other in terms of plan. This contributes to the displacement of the initial jets in two mutually perpendicular directions, which ensures a uniform load on the cross section of the aerocontactor 27. At the same time, the greatest compactness of the falling jets takes place in the upper layers of the multilayer nozzle 3, the rails 32 of which have small angles of inclination to the horizontal close , for example, to ZO3. This contributes to both the rapid dispersion of flows over the entire cross section of the aeronautical 27, and their fragmentation on the inclined planes of the rails into drops and small streams. In the lower layers of the multilayer nozzle 31, the hydraulic load on the cross section of the aerocontactor is basically aligned, so it is advisable to arrange the slats at a significant angle of inclination to the horizontal, for example, to 60 °. This will reduce the aerodynamic resistance of the aerocontactor during countercurrent air movement with respect to the sludge medium, and also contributes to the saturation of the liquid film flowing down the multilayer

nozzles The angle of inclination of the rails, close to 60 °, is also desirable from the point of view of the self-cleaning of the rails from the particles of liquid sediment during the period of shutdown of the aerocontactor from work. The natural creep angle of the liquid sediment is close to 50. Cleaning the top rails, whose slopes to the horizontal are close to

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under the influence of compact jets of sludge medium in the initial periods of the aerocontactor operation.

The ratio of the angles of inclination of the rails in the closest in height of the aerocontactor 5 layers x of the same orientation, equal to ob, / (180 ° oin, where n is the order number of the layer of the same orientation, creates a zigzag motion of the falling jets of fluid, which increases the path and, accordingly, the gas contact time 1.5-2 times, causing a corresponding increase in the oxidative and cooling effects of the Aero-contactor.

The signal for switching on the electric motor 29 of the submersible axial pump 28 is the indication of the level gauge 45, corresponding to an increase in the level in the measuring chute 18. This control action, carried out through the direct communication line of the automatic speed controller 44, in accordance with the indications of the dissolved oxygen analyzer 46 installed at the critical point of the aerotank and affecting the activation of the electric motor 29 of the submersible axial pump 28 according to the feedback scheme. Such control of the inclusion of electric motors 29 will allow the development of corrective commands in cases where a significant increase in the inflow of weakly contaminated sewage only slightly increases the load of organic matter, so that additional oxygen can be added and the associated energy the costs possibly more closely corresponded to the loads on the activated sludge, the electric motor 29 is connected to the automatic speed controller 44, the number of revolutions of the submersible electric motor the body and the associated recirculation sludge flow rate using an automatic speed controller 44 changes in such a way that in the period of increased

Effluent, water in the whole range of changes in the number of incoming substances, the concentration of dissolved oxygen is maintained at a level of 2 mg / l.

The signal for turning on the electric motor 39 of the axial fan 38 comes from the electrocontact thermometer 48 installed in the measuring tray 18. This control action, carried out according to the scheme of direct communication, is corrected in accordance with the indications of the electrocontact thermometer 49 installed at the critical point mixing corridor 5 aerotank, and affects the inclusion of the electric motor 39 according to the feedback scheme. The speed of the motor 39 of the axial fan 38 and the associated amount of air drawn into the aero-contact 27, which determines its cooling effect, is changed by the automatic speed controller 47 in such a way that the temperature in the aeration tank during the period of increased flow of waste water maintained at a given level.

The invention allows to reduce energy and capital costs.

Claims (4)

1. A device for wastewater treatment with activated sludge, containing an aerotank case divided by longitudinal and transverse partitions into direct and reverse mixing corridors with initial and final compartments, an extension corridor, a regenerator, a recirculation unit, channels of the original, purified waste water and return sludge, fine-bubble dispersers of constant action, attached to the air-blower, differing from the fact that, in order to increase the efficiency of the cleaning process and in the conditions of fluctuations of the inflow, the composition and wastewater temperature, it is equipped with a measuring chute and a distribution and control channel connected to the source wastewater channel, installed in the initial compartment of the forward mixing corridor and in the final compartment of the backward flow 1576492Y a separate corridor, a small inflow chute and an increased inflow chute with a dividing transverse partition, the recirculation unit is made in the form of an aerocontactor and a recirculation pipe connected to it 0 five 0 five 0 five 0 five water supplied in the lower part with a submersible axial pump with an electric motor; the aerocontactor is equipped with a multi-layer nozzle made in the form of inclined rails, in the upper part a diffuser located in the last axial fan with an electric motor located above the nozzle with a distributor tray with triangular overflows attached to the recycle The cisin pipeline, with the aero contact installed above the initial compartment of the direct mixing corridor and in communication with the atmosphere in the upper and lower parts, and the recirculation pipe is located in the final compartment of the back mixing corridor. 2. The device according to claim 1, about 1 t and more so that the layers of the nozzle of the aerocontactor are made with the transverse and longitudinal orientation of the rails. 3. The device according to claim 1, characterized in that it is equipped with an automatic speed controller connected to the pump electric motor, level gauges installed in the measuring tray, and between the initial and final compartments of the direct mixing corridor - a dissolved oxygen analyzer; speed according to the direct control connection scheme is connected to the level gauge, and according to the reverse control connection scheme - to the analyzer. 4. The device according to claim 1, characterized in that it is equipped with an automatic speed controller connected to the fan motor, two electro-contact thermometers, one of which is connected to the speed-control regulator according to the direct control circuit and installed the measuring tray and the other is connected to the same controller according to the feedback control circuit and is installed between the initial and final compartments of the forward mixing corridor. 4329 Fiag one Compiled by A. Davyd N. Editor N. Gunko Tehred M. Khodanych Proofreader T. Malets Order 1826 Circulation 793 VNIIPI State Committee for Inventions and Discoveries at the State Committee on Science and Technology 113035, Moscow, Raushsk nab. 4/5 Production and Publishing Combine Patent, Uzhgorod, ul Gagarin, 101 Subscription