RU2207985C1 - Water ozonizer and water ozonizing method - Google Patents

Abstract

FIELD: water treatment equipment and method. SUBSTANCE: water ozonizer is made in the form of individual container-type modules and has reaction vessel formed as contact basin provided with dispersing units adapted for forming air-ozone mixture bubbles and made in the form of plates with narrowing channels having diameters of inlet and outlet openings of 180-200 microns and 100-150 microns, respectively. Device for reducing weight of residual ozone has nozzles connected to water source and fixed in upper part of contact basin above water surface. Nozzles are designed for spraying water above surface of water to be treated, with volumetric ratio thereof being 1-20: 100, respectively. Method involves forming air- ozone mixture bubbles of 1-2 mm diameter for increasing area of cooperation of ozone with water under treatment process and for reducing weight of residual ozone in air-ozone mixture; directing air-ozone mixture through plates with narrowing channels having diameters of inlet and outlet openings of 180-200 microns and 100-150 microns, respectively; spraying water above surface of water to be treated at their volumetric ratio of 1-20:100. Water ozonizer and water ozonizing method may be used for disinfecting potable water in water supply systems. EFFECT: increased efficiency and improved quality of water treatment due to increased extent of ozone usage and provision for transportation of water ozonizer by making it in the form of individual container-type modules. 13 cl, 1 dwg, 1 tbl

Description

 The invention relates to techniques for treating water by oxidation using ozonation. It can be used, in particular, for the disinfection of drinking water in the water supply systems of cities and other settlements, for the disinfection of recycled water in pools and for the treatment of wastewater from industrial enterprises.

State of the art
The attractiveness of ozone compared to other oxidizing agents used to treat water is primarily due to its high oxidizing properties and the ability to effectively destroy various inorganic and organic compounds, as well as pathogenic microorganisms, including those resistant to other oxidizing agents, such as chlorine. The possibility of producing ozone at the treatment plant itself eliminates the need for its transportation and storage. In addition, when water is ozonized, its unpleasant taste and smell disappear, transparency increases and the content of dissolved oxygen increases. The decomposition of residual ozone proceeds quickly, with the release of oxygen, without the formation of toxic compounds.

A large number of methods and devices for producing pure water by the ozonation method are known, including a method for producing water with a high concentration of ozone, comprising contacting the ozone-containing gas with the source water sprayed in the form of small drops. The method is carried out in a device including a chamber, in the upper part of which nozzles for spraying the source water and nozzles for supplying ozone-containing gas are located, and in the lower part in which the treated water accumulates, there is a nozzle for draining it (EP 0430904 A1, 05.06.91) . The disadvantage of this technical solution is that it does not provide for the decomposition of residual amounts of ozone that is released into the atmosphere. Due to the fact that the MPC of ozone in the air is 1 mg / m ³ , the urgent task is to reduce its concentration in gas emissions.

 The installation known from RU 2114069 C1, 06/27/98 partially solves this problem. It contains an ozonizer, a pump, two contact tanks connected by pipelines with vertical injection elements formed by annular nozzles for jet flow of liquid embedded in the tube sheet, and by dip tubes mounted in another lower tube sheet coaxially with the nozzles. Above the first grate there is a nozzle for supplying the treated water, and above the second one there is a nozzle for supplying an ozone-air mixture. The outlet fitting of the spent ozone-air mixture is connected to a device for decomposing residual ozone, for example, a catalyst box. This technical solution allows to increase the degree of utilization of ozone and reduce environmental pollution. However, this device is quite complex. In addition, ozone is not used fully enough in the main process and a significant amount of this gas is lost due to decomposition.

 A device for ozonation of water is known, containing an air preparation system connected to an ozone generator equipped with a power source, a reaction vessel, in the lower part of which are dispersants in communication with the ozone generator, as well as an excess ozone treatment system. The water treatment method implemented in this device includes the synthesis of ozone from pre-cooled and dried air, passing ozone dispersed by a dispersant through a layer of treated water, treating excess ozone by heating and decomposing it on a catalyst, and filtering water (RU 2114790 C1, 07/10/1998) . The indicated method and device are the closest analogue of the claimed invention and have the following disadvantages: the degree of use of ozone in the process of water treatment is not quite optimal, a noticeable amount of residual ozone is formed, which is consumed unproductively, entering the chemical decomposition.

Disclosure of Invention
The technical problem to which the present invention is directed is to increase the efficiency and quality of water treatment by increasing the degree of use of ozone. Another important result is the ability to create a mobile installation consisting of modules that do not require large investments.

 The problem is solved in that the installation for ozonation of water containing a pre-treatment air system, connected via pre-prepared air to at least one ozone generator equipped with a power source, which is connected through the ozone-air mixture to the reaction vessel in communication with the source being processed water, having a bypass pipe of purified water and equipped with dispersants for the formation of bubbles of the ozone-air mixture in the water of the reaction vessel, and in which means for reducing the mass of residual (unreacted) ozone is considered, according to the invention it is made in the form of separate container-type modules, the reaction vessel is a contact pool in which dispersants for forming ozone-air mixture bubbles are made in the form of a porous plate or a plate with narrowing channels for transmission ozone-air mixture, in which the diameters of the inlet and outlet are 180-200 μm and 100-150 μm, respectively, and a means for reducing the residual mass ozone is made in the form of nozzles connected to a water source and located in the upper part of the contact pool above its mirror, providing spraying of water over the entire mirror of the treated water at a volume ratio of 1-20: 100, respectively.

 Separate modules of the container type can be performed in a mobile or stationary version, and the number of modules in the installation can be from four or more.

 One of the container-type modules is an air pre-treatment module, the other is an ozone production module, which includes at least one ozone generator, and the third is a reactor module, which includes a reaction vessel, dispersants are located in the lower part and nozzles are installed in the upper part .

 The air pre-treatment module contains cooling and dehumidification units.

 The installation is additionally equipped with a control and management system module and an energy supply module. Management of the operation of all modules can be combined in a module of a common monitoring and control system or can occur separately.

 The installation is additionally equipped with a thermoregulation module, an ozone-air mixture cooling means is provided in the ozone production module through which communication with the reaction vessel is carried out, and the reactor module is equipped with a spent ozone-air mixture purification unit. The thermoregulation module of the installation provides the optimal temperature regime of the equipment.

 In the upper part of the contact pool above its mirror, over its entire surface, there is a system for reducing the mass of residual ozone, made in the form of at least one unit of nozzles connected to a source of sprayed water. Such a source of water for nozzles is the source of the source water or the contact pool itself.

 Dispersant plates are made 1-6 mm thick. The lower limit is due to the preservation of the rigidity of the plate, and the upper limit is to ensure sufficient gas permeability of the plate. For wafers, for example, alloys based on titanium or glass ceramics according to the principle of "Schott filters" are used as a material resistant to prolonged exposure to ozone and water.

 The contact pool is divided into sections by vertical partitions, alternating between each other, adjacent to the bottom and installed with a gap relative to the bottom, with each dispersant installed in a section in which nozzles are also located.

 This design is given as an example, due to which water flows from section to section.

 The number of sections in the contact pool can be 2-10. The upper limit of the number of sections is selected from the conditions for ensuring the performance of a typical stationary installation. Fewer sections are used in mobile installations.

 The installation is equipped with a water filtration system before it is supplied to the contact pool and / or after it.

 The unit for purification of the spent ozone-air mixture before the release of its atmosphere contains a heater and / or catalyst.

 Both the filtration system and the purification unit can structurally be part of the reactor module.

 The problem is also solved by the fact that in the method of ozonation of water, including preliminary preparation of air by draining and cooling it, supplying it to an ozone generator to obtain an ozone-air mixture at its outlet, followed by its supply to the reaction vessel and passing through the treated water, after which the mass of residual ozone is reduced, according to the invention, to increase the surface of interaction of ozone with treated water, bubbles of an ozone-air mixture with a diameter of 1-2 mm are formed by passing it through a plate with tapering channels, the diameters of the inlet and outlet openings of which are 180-200 μm and 100-150 μm, respectively, and the mass of residual ozone in the ozone-air mixture is reduced by spraying water over the entire mirror of the treated water at a volume ratio of respectively 1-20: 100. Preferably, when the ozone-air mixture is supplied to the contact pool of the reaction vessel, while the treated water is supplied sequentially from one section to the other of the contact pool, alternately ascending and descending flows, preferably in each section the ozone-air mixture stream from the treated water and the sprayed water stream direct towards each other.

Before being fed to the ozone generator, the air is drained and cooled to a dew point from minus 60 to minus 65 ^{o C.} and fed to the ozone generator at a temperature from plus 5 to minus 30 ^o C.

 For purification from mechanical impurities, before the treated water is supplied to the contact pool and after the water treated from the contact pool is released, the latter is purified by filtration.

 To remove traces of ozone that may still remain in the spent ozone-air mixture, the spent ozone-air mixture is heated and / or passed through the catalyst bed of the purification unit before being discharged into the atmosphere.

 The indicated porosity or, alternatively, the shape and dimensions of the channels of the dispersant plates contribute to the fine atomization of the ozone-air mixture, its good solubility in water and the effective effect of ozone on impurities.

 The presence of a block of nozzles placed in the above manner, and ensuring the optimal volume ratio of the water sprayed and treated in the contact pool, allows to minimize the amount of residual ozone in the ozone-air mixture, which is subsequently supplied to the cleaning block, where it is heated and / or passed through the catalyst .

Brief Description of the Drawing
The invention is illustrated by the drawing, which schematically shows the installation for ozonation of water in the form of container-type modules (the most preferred embodiment of the installation according to this invention).

Preferred Embodiment
The installation for ozonation of water according to the invention is made in the form of separate container-type modules, the main of which are air pre-treatment module 1, ozone production module 3 and reactor module 5.

 Module 1 contains an air pretreatment system. The air pre-treatment system in turn comprises a cooling and drying unit 2. The ozone producing module 3 comprises at least one ozone generator 4 provided with an electric power source (not shown). The reactor module 5 contains a reaction vessel, which is in communication with the source of the treated water and has a drain pipe of purified water. The reaction vessel is a contact pool 6. The installation is also equipped with a water filtration system (not shown in the drawing) before it is supplied to and / or after the contact pool and a purification unit for the spent ozone-air mixture (not shown) before its discharge, containing a heater and / or catalyst. Dispersants 7 are placed in the lower part of the pool 6 for the formation of bubbles of the ozone-air mixture in water. In the upper part of the basin 6, a means is provided for reducing the mass of residual (unreacted) ozone. Each dispersant 7 for the formation of bubbles of the ozone-air mixture is made in the form of a porous plate or plate with tapering channels. If the dispersant 7 is formed by a porous plate, then the pore sizes are 10-150 microns. If the dispersant 7 is formed by a plate with tapering channels, then the diameters of the inlet and outlet for the ozone-air mixture of the channel openings in the plate are 180-200 μm and 100-150 μm, respectively. Means for reducing the mass of residual ozone is made in the form of nozzles 8 connected to a water source and placed in the upper part of the contact pool above its mirror. The source of water for the nozzles is the source of the source water or the contact pool itself. The installation is additionally equipped with a temperature control module (not shown in the drawing). In the module 3 for the production of ozone provides a means of cooling the ozone-air mixture (not shown). The ozone-air mixture module 3 is in communication with the reaction vessel, and the reactor module 5 is equipped with a spent ozone-air mixture purification unit (not shown). The installation also includes a module 10 of a control and management system and a power supply module 11.

 Contact pool 6 can be made in the form of one section or divided by partitions 9 into two or more sections. The optimal number of sections is 2-10.

 The installation according to the invention operates as follows.

Atmospheric air is usually supplied under pressure of 4-6 atm to air pre-treatment module 1, where it is cleaned, dried and cooled in blocks 2 to the dew point, for example, from minus 60 to minus 62 ^o С, and then at a temperature, for example, from plus 5 to minus 10 ^o C is fed to the ozone production module 3, where using ozone generators 4, the power sources of which are connected to the energy supply module 11, ozone is produced, which is sent to the reactor module 5 as part of the ozone-air mixture, where, passing through dispersants 7, the belly is formed rki ozone-air mixture, which is passed through the treated water contact basin 6 of the reaction vessel. Preferably, the water is treated in a flowing contact pool in which water flows at a predetermined speed (flow rate) from the entrance to the exit.

 Bubbles of an ozone-air mixture 1-2 mm in size pass through a layer of treated water, at such sizes of bubbles their ascent slows down, as a result of which part of the ozone is carried away with the treated water. Residual (unreacted) ozone in the composition of the ozone-air mixture enters the space above the surface (mirror) of the treated water in the contact pool 6. Most of the residual ozone in the composition of the ozone-air mixture is absorbed by the water sprayed through nozzles 8 over the entire mirror of the treated water when volume ratio, respectively equal, for example, 5-20: 100, while fresh water can be supplied to the nozzles from the water supply system to the contact pool 6 or the recirculation system processed in the contact pool 6 water.

 Residual ozone in the composition of the ozone-air mixture, which was not absorbed by the water sprayed by the nozzles 8, is fed to a purification unit (not shown in the drawing), where it is heated and / or passed through a catalyst.

 In the process of ozonation of water, water quality is monitored at the inlet and outlet of the installation, i.e., the composition of impurities is analyzed. It is also possible to control the pressure or flow rate, air pressure and ozone and other indicators. Before ozonation, water can be purified in various ways, for example by multi-stage filtration. In those cases when a precipitate or a suspension of solid inclusions is formed during treatment with ozone in water, it is filtered before being supplied to the consumer. Filter blocks are not shown in the drawing.

 Example 1

For the treatment of water with ozone, a plant was used, the scheme of which is shown in the drawing. Atmospheric air was cooled and dried in blocks 2 to a dew point of minus 60 ^° C, after which air was supplied to ozone generators 4 at a pressure of 1.6 kgf / cm ² and a temperature of plus 5 ^{° C.} The resulting ozone-air mixture was introduced into the contact pool 5. The treated water flowed at a speed of 2 cm / sec from the entrance to the contact pool to its exit, passing through the first and second sections. The height of the water layer was 4 m. Full renewal of water in the pool took place within 20 minutes. In its lower part, dispersing agents 7 were arranged uniformly over the entire cross-section, made in the form of porous plates 4 mm thick with pore sizes of 70 μm, through which an ozone-air mixture was introduced. Bubbles of the ozone-air mixture formed on the surface of the plates, which, upon reaching a size of 2 mm, detached and, passing through a layer of water, mixed with it and dissolved (the solubility of ozone in water is 210-400 mg / l in the temperature range from plus 2 to plus 20 ^o C). The ozone concentration in water was 20 mg / L. Ozone reacted chemically with the impurities in the water and oxidized them. The ozone utilization in the water layer was 90%. The residual amount of ozone in the composition of the ozone-air mixture entered the upper part of the contact pool and interacted with fresh water sprayed through nozzles 8, introduced from the water supply system into the pool. The droplet size was 1-2 mm. The volume ratio of the sprayed water and the treated water located in the contact pool was 5: 100. The ozone utilization rate in this case increased to 98%. The residual ozone in the composition of the ozone-air mixture was passed through the purification unit before being discharged into the atmosphere, where it was disposed of by heating to a temperature of 90 ^o С. The monitoring and control system ensured uninterrupted water supply, its treatment, monitoring of various parameters and blocking from emergency situations.

 The table below shows some indicators of water quality before and after ozone treatment. The data presented indicate a high quality water treatment with ozone, carried out by the proposed method using the proposed device.

 Example 2

 Water ozonation was carried out analogously to example 1, except that instead of a two-section contact pool, a contact pool was used in the installation, which was divided into 4 sections by vertical, transverse, alternately adjacent to the bottom and installed with a gap relative to the bottom partitions. A unit of nozzles was placed in each section, while the treated water was supplied sequentially from one section to another in the contact pool by alternately ascending and descending flows, preferably in each section the ozone-air mixture stream from the treated water and the sprayed water stream were directed towards each other. Water flowed from section to section from the entrance to the contact pool to its outlet at a speed of 4 cm / sec. As dispersants, we used 6 mm thick plates with channels in the shape of a truncated cone, the diameter of which at the input and output of ozone was 200 μm and 150 μm, respectively.

 The size of the bubbles of the ozone-air mixture, tearing from the dispersants, was 2 mm. The volume ratio of the sprayed water, which was used as water from the contact pool recirculation system, and the treated water located in the contact pool was 1:50. In addition, an additional contact pool was used, identical to the main one, into which the residual ozone-air mixture from the main pool was introduced through dispersants. The water obtained as a result of the treatment met all drinking water quality standards.

Industrial applicability
The developed installation modules have overall and mass characteristics, in which it is possible to transport them in containers in any mode of transport: automobile, rail, water and air, which significantly expands the scope of its use compared to existing analogues that are unsuitable for transportation, as they are made in the form of capital industrial facilities.

The proposed division of the installation into container-type modules allows varying its performance over a wide range by sequentially connecting standard modules, which can provide the needs of a single consumer, for example, a single summer house, or the needs of a whole summer cottage village. In addition, the proposed modules can also be used as part of a stationary sewage treatment plant of any settlement, including a megalopolis. The area for placement of the installation modules is, respectively, for the first case, 18 m ² and 27 m ² . Along with the possibility of transportation, the proposed installation provides water purification in compliance with the required standards and ensures environmental safety, as it provides means to reduce the mass of residual (unreacted) ozone within the allowable concentrations.

Claims (13)

 1. Installation for ozonation of water, containing a pre-treatment air system, connected via pre-prepared air to at least one ozone generator equipped with a power source, which is connected through a ozone-air mixture to a reaction vessel in communication with a source of treated water having an outlet a pipeline of purified water and equipped with dispersants for the formation of bubbles of the ozone-air mixture in the water of the reaction vessel, and in which a means for reducing sss of residual unreacted ozone, characterized in that the installation is made in the form of separate container-type modules, the reaction tank is a contact pool, in which dispersants for forming bubbles of the ozone-air mixture are made in the form of a plate with tapering channels for passing the ozone-air mixture, which the diameters of the inlet and outlet openings are 180-200 and 100-150 μm, respectively, and the means for reducing the mass of residual ozone is made in the form of nozzles connected to a source ICOM water and placed in the upper portion of the trolley basin over its mirror providing the water spraying over the whole of the mirror when the treated water volume ratio respectively equal to 1-20: 100.  2. Installation according to claim 1, characterized in that one of the container-type modules is an air pre-treatment module, the other is an ozone production module, including at least one ozone generator, and the third is a reactor module, including a reaction vessel.  3. The installation according to claim 1 or 2, characterized in that it is additionally equipped with a module of a monitoring and control system and an energy supply module.  4. Installation according to any one of claims 1 to 3, characterized in that it is additionally equipped with a thermal control module, an ozone-air mixture cooling means is provided in the ozone production module through which communication with the reaction vessel is carried out, and the reactor module is equipped with a waste ozone purification unit -air mixture.  5. Installation according to claim 1, characterized in that the source of water for the nozzles is the source of the source water or the contact pool itself.  6. Installation according to claim 1, characterized in that the contact pool is divided into sections by vertical partitions, alternating between each other, adjacent to the bottom and installed with a gap relative to the bottom, each dispersant is installed in the sections in which the nozzles are also located.  7. Installation according to claim 1, characterized in that it is equipped with a water filtration system before it is supplied to the contact pool and / or after it.  8. Installation according to claim 4, characterized in that the unit for cleaning the spent ozone-air mixture before it is released into the atmosphere contains a heater and / or catalyst.  9. A method of water ozonation, including preliminary preparation of air by draining and cooling it, supplying it to an ozone generator to obtain an ozone-air mixture at its outlet, then supplying it to the reaction vessel and passing it through the treated water, after which the residual ozone mass is reduced characterized in that they form bubbles of an ozone-air mixture with a diameter of 1-2 mm by passing it through a plate with tapering channels, the diameters of the inlet and outlet openings of which are respectively 180-200 and 100-150 microns, and a decrease in the mass of residual ozone in the ozone-air mixture is carried out by spraying water over the entire mirror of the treated water at a volume ratio of 1-20: 100, respectively.  10. The method according to claim 9, characterized in that the ozone-air mixture is fed into the contact pool of the reaction vessel, while the treated water is supplied sequentially from one section to another contact pool, alternately ascending and descending flows, and preferably in each section the ozone air mixture from the treated water and the stream of sprayed water is directed towards each other. 11. The method according to claim 9, characterized in that before being fed to the ozone generator, the air is drained to the dew point from minus 60 to minus 65 ^{o C.} and fed to the ozone generator at a temperature from plus 5 to minus 30 ^o C.  12. The method according to claim 11, characterized in that before the treated water is supplied to the contact pool and after the treated water leaves the contact pool, the latter is purified by filtration.  13. The method according to claim 11, characterized in that before being discharged into the atmosphere, the spent ozone-air mixture is heated and / or passed through a catalyst bed of the purification unit.

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