RU2798481C1 - Device and method for processing liquid medium - Google Patents

Abstract

FIELD: electrochemistry.

SUBSTANCE: complex processing of a liquid medium flow without the use of chemical reagents. The liquid medium processing device contains a chamber in which an inlet diaphragm, a rod electrode, a control electrode and a ring electrode are arranged in series. The electrodes are made with the possibility of forming a plasma that evenly and completely occupies the body volume between the rod electrode and the annular electrode. The liquid medium supply pipe is installed on the side of the inlet diaphragm, which is configured to provide a pressure jump at the inlet to the plasma region and thereby form a two-phase flow, including the liquid phase and the vapor phase. The device contains a diffuser installed on the side of the chamber, opposite to the location of the liquid medium inlet pipe, in which, by means of valves, a pressure is created higher than in the chamber, to ensure the condensation of the vapor phase of the two-phase flow. Behind the diffuser at the exit from the chamber there is a discharge branch pipe. The device contains an alternating voltage generator for supplying voltage to the rod electrode and the ring electrode and a control voltage generator for supplying voltage to the control electrode. The treatment of the liquid medium is carried out using the device described above. Ensure the flow of a liquid medium. A supersonic two-phase flow of a liquid medium is formed and processed in a plasma discharge. Carry out the increase in pressure in the treated two-phase flow of the liquid medium to ensure the condensation of the vapor phase. Provide complete coverage of the two-phase flow of the liquid medium by the plasma discharge.

EFFECT: increasing the efficiency of processing a liquid medium, in particular, by essentially complete coverage of the volume of the treated medium with a homogeneous plasma in the area of its plasma treatment with the possibility of controlling the plasma parameters to select the most optimal processing mode and the possibility of processing various liquid media.

6 cl, 2 dwg

Description

Technical field

The present invention relates to devices and methods for processing a liquid medium, in particular, to the complex processing of a liquid medium flow using plasma discharge, ultraviolet radiation, ultrasound, etc., without the use of chemical reagents. The invention can be applied, for example, to the separation of gases from liquid media.

State of the art

From patent RU2637026, a device for processing an aqueous medium in a stream is known, containing a reaction chamber with an inlet pipe and an outlet pipe and a first-stage nozzle element installed at the inlet to the reaction chamber, providing a pressure drop at the inlet to the reaction chamber, as well as a diffuser located at the outlet from the reaction chamber to slow down the flow. The reaction chamber is made of a dielectric material and is formed by two ring electrodes sequentially installed in it along the flow, spaced along the length of the chamber to create a longitudinal plasma discharge in the cavity of the reaction chamber. The method for treating an aqueous medium by means of said device includes directing the flow under pressure to the element of the first stage of the nozzle with further outflow of the flow into the reaction chamber for treating the aqueous medium with the formation of a two-phase gas-liquid flow, followed by deceleration and condensation of the two-phase flow at the outlet of the reaction chamber. At the same time, a longitudinal plasma discharge is created in the reaction chamber, which initiates radiation in the ultraviolet region (UV radiation) and the synthesis of ozone from oxygen released from the aqueous phase during the formation of a two-phase gas-liquid flow, and when the flow is decelerated at the outlet of the device by the collapse of gas bubbles, an ultrasonic sound is created. field and local overheating of the flow of the aquatic environment. The technical result consists in increasing the efficiency of water disinfection with an increase in microbiological indicators of the quality of the aquatic environment.

A disadvantage of the known device for processing an aqueous medium in a stream and the method of its operation is the rather high inhomogeneity of the plasma over the cross section of the treated aqueous medium, which reduces the processing efficiency.

Another device for disinfecting water and its method of operation are disclosed in patent EA026813. The device includes a means for introducing the flow of the original product; a liquid atomizer designed to create, by abrupt depressurization, a two-phase mixture from the feedstock in the liquid phase; a reactor having a pair of electrodes connected to a voltage source that is capable of generating a voltage in excess of the breakdown voltage of said two-phase mixture; and a liquid condenser for returning said two-phase mixture to a liquid state. The method according to embodiments of the present invention includes converting a single-phase flow into a two-phase flow consisting of liquid and gas or liquid and vapor, which can be achieved by passing the flow from a high pressure zone to a low pressure zone, for example, in a plasma chamber. This transition can be implemented through a diaphragm, an ultrasonic hydrodynamic transducer, or any other device capable of spraying liquid. The method involves plasma ignition inside a two-phase mixture. The two-phase flow in which the discharge is created has a dynamic structure in the form of an accumulation of particles with a significant interface between the gas and liquid phases. By changing the pressure at the nozzle inlet and the counterpressure in the outlet pipe, it is possible to change the ratio between the gas and liquid phases in the flow and the mode of stable discharge burning, and, consequently, the direction and speed of chemical reactions occurring in the plasma chamber. As the present inventors point out, the method of influencing a liquid with plasma particles is based on converting the liquid into a mixture of liquid droplets suspended in the gas phase and having a diameter of a few tenths of a micrometer or less, and igniting the plasma in the gas phase.

As in the device described above and its method of operation according to RU2637026, when implementing the invention according to EA026813, it is impossible to ensure plasma uniformity over the cross section of the processed two-phase mixture, which reduces the processing efficiency. The need for said transformation of the liquid into a mixture of liquid droplets suspended in the gas phase also leads to a decrease in efficiency.

In addition, the known devices and methods for the treatment of liquid media, including those mentioned above, as a rule are not universal, but are intended for the treatment of specific liquids for specific purposes, in particular, only microbiological treatment of water.

A technical problem that arises when using known devices for processing a liquid medium, but solved by the present invention, is the creation of a device and a method for processing a liquid medium, which ensures the most complete coverage of the volume of the processed medium with a homogeneous plasma with the possibility of wide regulation of plasma parameters for various types of processing of various liquid avg.

Disclosure of the essence of the invention

The technical result of the present invention is to increase the efficiency of processing a liquid medium, in particular, by essentially complete coverage of the volume of the treated medium with a homogeneous plasma in the area of its plasma treatment with the possibility of controlling the plasma parameters to select the most optimal processing mode and implement various types of processing of various liquid media.

The specified technical problem is solved, and the claimed technical result is achieved in a device for processing a liquid medium, containing a chamber in which an inlet diaphragm, a rod electrode, a control electrode and an annular electrode, a liquid medium supply pipe and a diffuser are located in series, located on opposite sides of the chamber, placed behind a diffuser outlet, an alternating voltage generator for supplying voltage to the rod electrode and an annular electrode, and a control voltage generator for supplying voltage to the control electrode.

Thanks to this design of the device, in particular, the use of a three-electrode system in which the control electrode has its own power source (control voltage generator), it was possible to ensure not only a fairly uniform and complete filling of the volume between the extreme electrodes with plasma, which significantly increased the efficiency of processing the flow of a liquid medium, but also within a fairly wide range of control of such filling in the processing of liquid media of a significantly different nature, that is, different composition, and for different purposes.

Unlike the processes used in a number of analogues, including the device and method according to EA026813, in the claimed invention, the liquid in a continuous stream of liquid medium boils due to a pressure jump at the inlet to the plasma treatment area, and as a result, gas is released from it. Further, in relation to the processing of an already two-phase flow of a liquid medium, the control electrode stabilizes the burning of the plasma, helping to eliminate or reduce to a minimum level the pulsation of the plasma discharge in the flow of the processed liquid medium; contributes to the formation of a plasma discharge two to three or more times longer than when using a two-electrode system, for example, described in RU2637026; expands the plasma discharge to the entire cross section of the plasma treatment area, while the plasma discharge becomes volumetric, rather than linear (streamer) - all this directly affects the efficiency of liquid medium treatment.

Finally, when using a control electrode, the plasma discharge can be carried out both in the positive zone, by applying a positive voltage, preferably constant, and in the negative zone, by applying a negative voltage, preferably constant, which makes the claimed installation universal in terms of the types of liquids being processed. environments and purposes of processing. In particular, it can be microbiological treatment of water for its subsequent domestic use; decomposition in aqueous media of organic compounds; decomposition of carbon dioxide, methane and other gases; production of hydrogen and oxygen; purification from sulfur and hydrogenation of oil fractions with an initial boiling point above 180°C without the use of catalysts; and much more.

In a preferred embodiment, the claimed device may contain at least one gas supply channel installed in the area of the rod electrode. In this case, the supplied gas helps to obtain a plasma with the specified parameters, combustion volume, uniformity and stability. In addition to or in addition to this, for the same purposes, the device may contain an additional pin electrode in the area of the ring electrode.

Another object of protection according to the present invention, which allows solving a technical problem and achieving the claimed technical result, is a method for processing a liquid medium, including providing a flow of a liquid medium, forming a supersonic two-phase flow of a liquid medium, processing a two-phase flow of a liquid medium in a plasma discharge, and increasing pressure in the flow of a two-phase flow of a liquid medium with the provision of condensation of the vapor phase. At the same time, essentially complete coverage of the two-phase flow of the liquid medium by the plasma discharge is ensured.

This method can be implemented, inter alia, by means of the liquid medium processing device described above.

In a particular embodiment of the claimed method, additional gas supply to the liquid medium flow is provided.

In general, the processing of a liquid medium in the specified installation includes directing the flow of a liquid medium under pressure to the diaphragm with further outflow of the flow into the chamber for processing the liquid medium with the formation of a two-phase supersonic gas-liquid flow and subsequent deceleration and condensation of the two-phase flow at the outlet of the chamber in a pressure surge. In this case, a longitudinal plasma discharge is created in the chamber, which initiates UV radiation and, usually, but not necessarily, the synthesis of ozone from oxygen released from the liquid phase during the formation of a two-phase gas-liquid flow. When the flow is decelerated at the exit from the chamber by the collapse of gas bubbles, an ultrasonic field and local overheating of the liquid medium flow are created. A control electrode is located in the chamber, which modulates the plasma discharge in such a way that it occupies essentially the entire volume between the rod electrode and the ring electrode.

Hereinafter, the invention is described in more detail with reference to the attached figures with possible embodiments of the invention presented thereon, to which, however, the present invention is not limited.

Brief description of the drawings

In FIG. 1 shows an embodiment of the claimed liquid medium processing device.

In FIG. 2 shows a variant of the scheme for switching on the claimed device as part of an installation for processing a liquid medium.

The positions in the figures indicate the following elements:

1 – liquid medium processing device;

2 - camera;

3 - input diaphragm;

4 - rod electrode;

5 - control electrode;

6 – ring electrode;

7 - branch pipe for supplying a liquid medium;

8 - diffuser;

9 - outlet pipe;

10 - alternating voltage generator;

11 – control voltage generator;

12 - gas supply channel;

13 - liquid medium supply line;

14 - shut-off valve;

15 - filter;

16 - pump for supplying a liquid medium under pressure;

17 – flow meter;

18 – liquid medium pressure sensor;

19 – liquid medium temperature sensor;

20 - gas supply line;

21 - control valve;

22 - vacuum gauge;

23 - output line;

24 - degasser;

25 – exit line of the processed liquid medium;

26 - gas outlet line;

27 - vacuum pump;

A is the zone of plasma treatment of the liquid medium flow;

B is the first area of the chamber;

C is the second area of the chamber;

E is the zone of formation of a two-phase flow of a liquid medium;

F is the stabilization zone (the third area of the camera);

D0, L0 are the diameter and length of the diaphragm;

D1, L1 – diameter and length of the rod electrode;

D2, L2 are the diameter and length of the first region of the chamber;

D3, L3 are the diameter and length of the second region of the chamber;

D4, L4 are the diameter and length of the stabilization zone (the third region of the chamber);

D5 is the diameter of the liquid medium supply pipe;

D6 is the diameter of the outlet pipe.

Implementation of the invention

The liquid medium treatment device 1 according to the invention is shown schematically in FIG. 1 and contains a chamber 2, in which the inlet diaphragm 3 is located in series at the inlet to the chamber 2, the rod electrode 4, the control electrode 5 and the annular electrode 6. On the side of the inlet diaphragm 3, the chamber 2 is adjacent to the branch pipe 7 for supplying the liquid medium being processed, and a diffuser 8 is placed on the opposite side of the chamber 2. Behind the diffuser 8, at the outlet of the chamber 2, there is an outlet pipe 9.

Chamber 2 is made of any suitable dielectric material, such as polytetrafluoroethylene (PTFE-4).

The electrodes 4, 5, 6 are made of a metallic electrically conductive material, preferably selected from the group including molybdenum, silver, copper, alloys of these metals, stainless steel, electrically conductive porous ceramics, graphite, siliconized graphite.

The liquid medium processing device 1 also includes an alternating voltage generator 10 for supplying voltage to the rod electrode 4 and ring electrode 6 and a control voltage generator 11 for supplying voltage to the control electrode 5 (generators 10, 11 are schematically shown in Fig. 2).

The inner region of the chamber 2 between the rod electrode 4 and the annular electrode 6 forms the zone of ignition of the longitudinal plasma discharge and, accordingly, the zone A of the plasma treatment of the liquid medium flow.

A longitudinal plasma discharge is created by applying an alternating voltage from 1000 to 4000 V with a frequency of 100 to 500 kHz and a current strength of 100 to 500 mA to the electrodes 4, 6 by means of a generator 10. The plasma discharge is initiated at a current of approximately 500 mA, and then the current is reduced to 100–300 mA, which, in comparison with analogues, reduces electrode wear.

In order to stabilize the plasma discharge and ensure uniform filling of essentially the entire volume of the chamber with plasma along its cross section, a constant voltage of positive or negative polarity of 1000 to 9000 V, preferably from 3000 to 7000 V, and a current strength is applied to the control electrode 5 by means of a control generator 11 from 50 to 200 mA, which is determined by the liquid medium and the type of its processing. In some cases, supply to the control electrode 5 by means of the control generator 11 of an alternating voltage, in particular, the indicated values of the amplitude and current, which is also determined by the liquid medium and the type of its processing, is provided.

Thanks to the use of control electrode 5, the plasma discharge can be carried out both in the positive zone, by applying voltage from +1000 to +9000 V, and in the negative zone, by applying voltage from -1000 to -9000 V, which is necessary for various tasks. The control electrode 5 made it possible to expand the plasma discharge to almost the entire cross section of the plasma impact zone on a two-phase flow of a liquid medium due to the fact that it was possible to turn the plasma discharge from a linear (streamer) into a volumetric one, so that in the claimed device the plasma occupies the entire volume of the chamber 2. In addition , the control electrode 5 makes it possible to form a plasma discharge two to three times longer than in the two-electrode version, known, for example, from RU2637026, and also stabilizes plasma combustion in a two-phase flow of the processed liquid medium, almost completely eliminating plasma discharge pulsations.

To ensure even more stable plasma combustion and its greater uniformity in the claimed device 1 for processing a liquid medium, an additional pin electrode (not shown in the figures) can be provided in the area where the ring electrode 6 is placed, made, in particular, from the same materials as the electrodes 4, 5, 6.

A longitudinal plasma discharge can be ignited both without the use of additional gases and with the use of such. In the second case, the installation 1 may be provided with at least one gas supply channel 12 installed in the area of the rod electrode 4. In addition, additional gases can be used in the processing of the liquid medium flow.

Diaphragm 3 is characterized by diameter D0 of aperture of diaphragm 3 and length L0.

The rod electrode 4 is characterized by a diameter D1 and a length L1, measured from the outlet edge of the diaphragm 3 to its end.

The electrodes 4, 5, 6 form three regions of the chamber 2, in which the liquid medium is processed, including the plasma discharge: the first region B, formed between the end of the rod electrode 4 and the control electrode 5 and characterized by the internal diameter D2 of the chamber 2 and the length L2 ; a second region C formed between the control electrode 5 and the ring electrode 6 or, if present, the end of the additional rod electrode, and having an inner diameter D3 of the chamber 2 and a length L3; and a third region in which plasma discharge treatment is not performed, formed between the ring electrode 6 and the end of the chamber 2 to which the diffuser 8 is adjacent, and having an inner diameter D4 of the chamber 2 and a length L4.

Thus, the first and second regions B, C form the aforementioned plasma treatment zone A, characterized by a total length L2 + L3. The diameters D2 and D3 of the plasma treatment zone A can be quite close to each other and significantly exceed the diameter D0 of the aperture 3.

The area of the chamber from the diaphragm 3 to approximately the end of the rod electrode 4 of length L1 is the area E of the formation of a two-phase flow of liquid medium, and the third area mentioned above is the stabilization area F.

These zones will be discussed in more detail below.

The branch pipe 7 for supplying liquid medium to the chamber 2 is characterized by a diameter D5, and the outlet branch pipe 9 at the outlet of the chamber 2 is characterized by a diameter D6.

The length L of the chamber 2 and its diameter D are preferably related by:

L= (10 ÷ 30) D,

where the diameter D of the chamber 2 is approximately the average of the diameters D2, D3 and D4, which are generally close to each other. As experiments have shown, with such a ratio of the length L and diameter D of the chamber 2, it is possible to use the voltage on the electrodes in the range from 1000 to 5000 V (or from -1000 to -5000 V), which is preferable from the point of view of energy saving.

In a preferred embodiment of the invention, the liquid medium is supplied to the liquid medium supply pipe 7 under pressure in the range from 0.2 to 6 MPa. At the same time, the pressure in the chamber 2 is maintained in the range from 1 to 10 kPa, in particular, by creating a back pressure at the outlet of the chamber 2, which is provided by the pressure of the gas released from the liquid in the degasser 24, and the exit of liquid and gas from the degasser 24 through control valves 21 for liquid and gas, installed respectively on the line 25 of the output of the processed liquid medium and the line 26 of the gas outlet (see Fig. 2).

The diameter D5 of the branch pipe 7 for supplying liquid medium and the diameter D6 of the outlet branch pipe 9 are selected from the condition of ensuring the velocity of the flow of the liquid medium in chamber 2 is not more than 1.0–1.5 m/s.

The diameter D0 of the diaphragm 3 is calculated from the condition of obtaining the minimum pressure in the liquid medium flow at the outlet of the diaphragm 3, in particular, corresponding to the saturation pressure of water at a given temperature. The length L0 of the diaphragm 3 preferably lies in the range (3÷15)·D0. In this case, several holes can be made in the diaphragm 3 with a total area corresponding to the area of one hole with a diameter D0. The number of holes in the diaphragm 3 is selected from the condition of maximum filling of the area of formation of a two-phase flow for its subsequent plasma treatment.

The value of the diameter D1 of the rod electrode 4 preferably lies in the range (0.4 ÷ 0.9)·D0, and its length L1 preferably lies in the range (10 ÷ 20)·D2.

The inner diameter of chamber 2 in the zone of formation of a two-phase flow is determined from the condition of the minimum local sound velocity of a liquid medium of 10–20 m/s and is (1.5 ÷ 2.5) D0 (or the equivalent diameter of the sum of the areas of several apertures of the diaphragm 3). The length of the two-phase flow formation zone, as mentioned above, is in fact approximately equal to the length L1 of the rod electrode 4.

The diameter D2 of the first region is determined from the condition of the minimum local sound velocity of the liquid medium 10÷20 m/s and is (1.5÷2.5)·D0 (or the equivalent diameter of the sum of the areas of several apertures of the diaphragm 3). The length L2 of the first region is (5 ÷ 10)·D2.

The length of the control electrode 5 is (0.5 ÷ 1.5)·D2.

The diameter D3 of the second region is determined from the condition of the minimum local sound velocity of the liquid medium 10÷20 m/s and is (1.5÷2.5)·D0 (or the equivalent diameter of the sum of the areas of several apertures of the diaphragm 3). The length L3 of the second region is (5 ÷ 10)·D3.

The length of the ring electrode 6 is (0.5 ÷ 1.5)·D3.

As mentioned above, the third region, characterized by the inner diameter D4 of the chamber 2 and the length L4, forms the stabilization zone F. In this case, the diameter D4 is determined from the condition of the minimum local sound velocity of the liquid medium 10÷20 m/s and is (1.5÷2.5)·D0 (or the equivalent diameter of the sum of the areas of several apertures of the diaphragm 3). The length L4 of the third region is (8 ÷ 15) D3.

The total opening angle of the diffuser 8 is preferably between 6° and 30°.

Next, with reference to FIG. 2 explains the operation of the claimed device 1 as part of a plant for processing a liquid medium.

In the general case, a liquid medium processing plant includes the claimed liquid medium processing device 1, as well as tanks for storing liquid medium and gases, supply lines (lines), control means (in particular, flow meters, vacuum gauges, etc.) and additional equipment.

In particular, the installation for processing a liquid medium may contain a line 13 for supplying a liquid medium to the installation 1 through a branch pipe 7 for supplying a liquid medium with a shut-off valve 14, a filter 15, a pump 16 for supplying a liquid medium under pressure, a flow meter 17, installed on the line 13 for supplying a liquid medium, a liquid medium pressure sensor 18 and a liquid medium temperature sensor 19; additional line 20 gas supply installed on it shut-off valve 14, control valve 21 gas supply, flow meter 17; vacuum gauge 22 to control pressure in chamber 2; outlet line 23 with a liquid medium pressure sensor 18 installed on it and connected to a degasser 24, from which the treated liquid medium outlet line 25 with a control valve 21 and a shut-off valve 14, as well as a gas outlet line 26 with a vacuum pump 27, a control valve 21 and stop valve 14.

The liquid medium to be processed is supplied to the device 1 through the line 13 under pressure, preferably more than 0.1 MPa, in particular from 0.1 to 6 MPa, created by means of the pump 16, through the liquid medium supply pipe 7 and the pre-filter 15 . The control of the current parameters of the flow of the liquid medium is carried out using the flow meter 17, the pressure sensor 18 and the temperature sensor 19 and, if necessary, regulate the flow of the liquid medium.

As mentioned earlier, in addition, but not necessarily, gas can be supplied to the installation 1 through the gas supply channel 12, for which a line 20 is provided in the liquid medium treatment plant. The flow rate of the supplied gas is set by means of the control valve 21 and is controlled by the flow meter 17.

The processing of the liquid medium in the flow is carried out by converting the flow of the liquid medium into a supersonic two-phase flow due to a sharp drop in pressure at the outlet of the diaphragm 3 (the first pressure jump) and plasma processing of the flow in the zone of plasma processing of the flow of the liquid medium, controlled by the control electrode 5 and followed by braking flow of the liquid medium during its expansion in the diffuser 8 (the second pressure jump).

The aperture 3 and the first region B of the chamber 2 form a nozzle. Due to the significant difference in diameters D0 and D2, D3, D4, the first pressure jump (drop) is realized, which creates a rarefaction zone in chamber 2. After passing through diaphragm 3, the flow rate of the liquid medium remains constant, but the flow becomes supersonic, as the speed of sound decreases. Thus, in the first and second regions B, C, forming the plasma treatment zone A, a rarefaction region is created, due to a sharp pressure drop, the liquid medium boils up with the release of vapors and dissolved gases from it and a two-phase supersonic flow is formed.

In the plasma treatment zone, a longitudinal controlled plasma discharge is ignited and it is passed through the specified two-phase supersonic flow. The pressure in the plasma treatment zone is controlled by a vacuum gauge 22.

A controlled plasma discharge, formed according to the present invention in fact in the entire volume of a supersonic two-phase flow of a liquid medium, initiates electromagnetic radiation in the ultraviolet region of the spectrum (170 ÷ 300 nm), the visible region of the spectrum (380 ÷ 400 nm) and the infrared region of the spectrum (760 ÷ 780 nm ). This radiation intensely affects the processed liquid medium.

The impact of the plasma discharge on the flow of the liquid medium is provided for a time of 0.1 to 10 ms, preferably 3 to 8 ms.

Then, after passing through chamber 2, the flow is subjected to the second shock - a sharp increase in pressure in the diffuser 8, which causes an avalanche-like condensation of the vapor phase of the two-phase flow. Generally speaking, the passage of flow through the diffuser 8 would cause a decrease in pressure in the flow. The increase in pressure is provided by creating a counterpressure through the valves 21 after the degasser 24.

During the implementation of the second pressure jump in the flow of a liquid medium, a spectrum of oscillations of various physical nature is formed, including ultrasonic and electromagnetic, which contribute to the collapse of gas bubbles, which, when collapsing, give rise to new oscillations. An avalanche-like process of collapse of gas bubbles is observed, which creates a powerful ultrasonic field and the local overheating of the liquid caused by it in the area of bubble collapse, as a result of which the thermal treatment of the liquid medium also occurs.

According to the present invention, all liquid medium processing processes take place in a continuous flow in the chamber 2 of the claimed device 1. These processes, in particular, are:

- hydrodynamic effect on the liquid medium in the flow, causing a sharp decrease in pressure until the liquid medium boils and the formation of a two-phase flow;

- impact on the flow of a liquid medium by a plasma discharge with the initiation of a wide spectrum of electromagnetic radiation (UV radiation, visible spectrum radiation, infrared radiation and radio frequency spectrum radiation);

- exposure to ultrasonic radiation generated in a liquid medium at the stage of the second jump (sharp increase) in pressure;

- synthesis and decomposition of gas separated from a liquid medium or gas introduced into the reaction chamber.

It can also be provided for the introduction of various metal ions into the liquid medium by choosing the appropriate electrode material.

The following are some examples of implementation of the claimed invention, which, however, do not limit its implementation.

Example 1. Microbiological water treatment.

Water from the Moskva River (water temperature 18–22°C) was supplied through main 13 via main 13 using pump 16 with a capacity of 1.5 m ³ /h through diaphragm 3 into chamber 2. The pressure at the inlet to liquid medium processing device 1 was 0.9 MPa .

Then the water flowed into the zone of formation of a two-phase flow of a liquid medium, where, due to its boiling with the release of water vapor and dissolved gases, a two-phase supersonic flow of an aqueous medium was formed, after which, in the zone of plasma processing of the flow, the two-phase flow was subjected to a controlled plasma discharge.

The plasma discharge was controlled using control electrode 5. The pressure in the zone of plasma treatment of the flow was 0.01 MPa; the pressure at the outlet of the liquid medium processing device 1 is 0.28 MPa. The diameters D1, D2, D3, D4 were 7 mm; gaps between electrodes 4, 5 and 6 - 50 mm each. Generator 10 provided a voltage between electrodes 4 and 6 of 3000 V and a frequency of 100 kHz. It was possible to use a higher frequency of the generator 10, and the higher the frequency, the more intensively the liquid is treated. When using a frequency of less than 100 kHz, a less stable, flickering plasma was formed, which is undesirable. Generator 11 provided a voltage on the control electrode 5 of -8000 or +8000 V. The total power consumption of generators 10, 11 and pump 16 was 2.5 kW. The time of exposure of the plasma discharge to the flow of the aqueous medium ranged from 10 ^-4 to 10 ^-2 s. At the outlet of device 1, samples were taken to measure the main indicator of water purity according to SanPiN 2.1.4.1074-01 - the total microbial number (TMC). For drinking water, TMF should be less than 50.

Two modes of operation of device 1 were used: the first mode, voltage +8000 V was applied to electrode 5; the second mode - a voltage of -8000 V was applied to electrode 5. The hydraulic mode of operation of device 1 was the same.

The conclusion of the certified laboratory showed the following.

Source water: water taken from the Moscow River. TMF = 5900 (hereinafter, at a temperature of 37°C).

First processing mode: MCH = 6.

Second processing mode: MCH = 6.

Thus, in any of the two treatment modes, the purity index of the treated water turned out to be significantly lower than the upper permissible limit.

Example 2. Decomposition of CO ₂ into CO and O ₂ without the use of catalysts.

Water from the Moscow water supply system (water temperature 18–22°С) was supplied via main 13 using pump 16 with a capacity of 20 l/min through diaphragm 3 to chamber 2. The pressure at the inlet to liquid medium processing device 1 was 0.9 MPa. Carbon dioxide was supplied to chamber 2 through channels 12. The flow rate of _CO2 was 4–5 L/min.

Then, water and CO ₂ flowed into the zone of formation of a two-phase flow of a liquid medium, where, due to intensive mixing and partial boiling of the aqueous medium with the release of water vapor and dissolved gases, a two-phase supersonic flow of the aqueous medium was formed, after which, in the zone of plasma treatment of the flow, the two-phase flow was subjected to controlled plasma discharge.

The plasma discharge was controlled using control electrode 5. The pressure in the zone of plasma treatment of the flow was 0.03 MPa; the pressure at the outlet of the liquid medium processing device 1 is 0.18 MPa. The diameters D1, D2, D3, D4 were 7 mm; gaps between electrodes 4, 5 and 6 - 50 mm each. Generator 10 provided a voltage between electrodes 4 and 6 of 3000 V and a frequency of 100 kHz. It was possible to use a higher frequency of the generator 10, and the higher the frequency, the more intensively the treatment of the liquid. When using a frequency less than 100 kHz, a less stable, flickering plasma was formed, which is undesirable. Generator 11 provided a voltage on the control electrode 5 of -4000 or +4000 V. The total power consumption of generators 10, 11 and pump 16 was 1.7 kW. At the outlet of the device 1, samples were taken for gas analysis through the line 26 of the gas outlet.

Three operating modes of setup 1 were used: the first mode, without plasma, and the second and third modes, with plasma of different powers.

For the second and third regimes, the time of exposure of the plasma discharge to the flow of the aqueous medium ranged from 10 ^-4 to 10 ^-2 s. During this period of time, from 47 to 59% of CO ₂ that entered chamber 2 decomposed.

The measurement results are shown in the table below.

Parameter Mode 1 Mode 2 Mode 3 Power consumption of the generator 10, kW 0 0.18 0.18 Power consumption of the generator 11, kW 0 0.375 0.46 The amount of gases sampled through line 26 of the gas outlet _CO2 , % 5.359 3.936 4.537 _O2 ,% 17.746 18.853 17.961 _N2 , % 69.981 63.447 53.082 _CH4 , % 0.00 0.00 0.00 CO, % 0 3.605 6.629 General, % 93.09 89.84 82.21 The amount of converted CO ₂ ,% 0 47.81 59.37

Example 3. An example of obtaining oxygen and hydrogen from water.

Water from the Moscow water supply system (water temperature 18–22°С) was supplied via main 13 using pump 16 with a capacity of 20 l/min through diaphragm 3 to chamber 2. The pressure at the inlet to liquid medium processing device 1 was 0.9 MPa. Carbon dioxide was supplied to chamber 2 through channels 12. The flow rate of _CO2 was 4–5 L/min.

Then the water flowed into the zone of formation of a two-phase flow of a liquid medium, where, due to the boiling of the aqueous medium with the release of water vapor and dissolved gases, a two-phase supersonic flow of the aqueous medium was formed, after which, in the zone of plasma treatment of the flow, the two-phase flow was subjected to a controlled plasma discharge.

The plasma discharge was controlled using control electrode 5. The pressure in the zone of plasma treatment of the flow was 0.02 MPa; the pressure at the outlet of the liquid medium processing device 1 is 0.18 MPa. The diameters D1, D2, D3, D4 were 7 mm; gaps between electrodes 4, 5 and 6 - 50 mm each. Generator 10 provided a voltage between electrodes 4 and 6 of 3000 V and a frequency of 100 kHz. It was possible to use a higher frequency of the generator 10, and the higher the frequency, the more intensively the treatment of the liquid. When using a frequency less than 100 kHz, a less stable, flickering plasma was formed, which is undesirable. Generator 11 provided a voltage on the control electrode 5 of -4000 or +4000 V. The total power consumption of generators 10, 11 and pump 16 was 1.7 kW. At the outlet of the device 1, samples were taken for gas analysis through the line 26 of the gas outlet.

Two modes of operation of the facility with plasmas of different powers were used.

The time of exposure of the plasma discharge to the flow of the aqueous medium was from 10 ^-4 to 10 ^-2 s. During this period of time, 2.3–2.5 nl/min was released. oxygen and hydrogen. Efficiency of use was 78–82%. In this case, the hydrogen concentration in the gas mixture was 80–90%.

According to literature data, in alkaline electrolysis, the theoretical specific energy consumption is approximately 3.54 kWh/Nm ³ , the practical specific energy consumption is 4.9 kWh/Nm ³ . Thus, the efficiency of primary energy use will be equal to 72%.

When using the claimed device and method for processing a liquid medium, the following parameters were used and the following results were achieved:

discharge voltage, mode 1 / mode 2 - 2.2 / 2.1 kV;

discharge current, mode 1 / mode 2 - 295 / 295 mA;

discharge power, mode 1 / mode 2 - 649 / 619.5 W;

the amount of released oxygen and hydrogen, mode 1 / mode 2 - 2.5 / 2.3 nl / min., or 0.15 / 0.138 nm ³ / hour;

specific energy consumption, mode 1 / mode 2 - 4.33 / 4.49 kWh / nm ³ ;

primary energy efficiency, mode 1 / mode 2 - 81.82 / 78.86%.

Thus, the claimed device and method made it possible to increase the efficiency of primary energy use.

Example 4. Purification of water from pollution by overestimated concentrations of ethylene glycol.

The bottom container was filled with tap water and kept for a day in order to remove residual dissolved chlorine from the water. Conducted weighing ethylene glycol 55 ml (according to the terms of reference at the rate of 60 mg/liter) and introduced it into 1 m ³ of water. Mixing took place in a bottom tank using a submersible centrifugal pump for two hours.

An initial water sample with dissolved ethylene glycol was taken. The original sample is characterized by the amount of ethylene glycol 63 mg/DM ³ .

The treatment of polluted water was carried out per channel, in one pass. The productivity of plant 1 was 1.2 m ³ /hour at a pressure of 9.7 bar at the inlet to diaphragm 3. The pressure in chamber 2 was 0.8 bar, the pressure at the outlet of chamber 2 was 1 bar.

Processing mode 1 - original sample without processing.

Processing mode 2 – initial sample with plasma discharge treatment in the positive zone (positive potential at control electrode 5).

Processing mode 3 – initial sample with plasma discharge treatment in the negative zone (negative potential at control electrode 5).

Treatment mode 4 – initial sample with two-phase flow treatment with ozone supply to the vacuum zone (from atmospheric air).

As a result of work on the treatment of water with an overestimated content of ethylene glycol in treatment modes 2, 3, it was possible to halve the content of ethylene glycol due to the use of a plasma discharge.

In processing mode 4, processing was carried out with a two-phase high-speed flow with the introduction of ozone, the processing time was 0.003–0.004 s. A highly effective effect of ozone was observed due to the developed contact surface of ozone with vapor-gas-liquid bubbles of the treated mixture.

Example 5. Purification of river water.

River water was taken with the value of TMC = 340.

Four processing modes were used, similar to those in Example 4.

Processing mode 2 made it possible to reduce TMF to 4, processing mode 3 to 3, processing mode 4 also to 3.

Thus, the use of the claimed liquid medium processing device made it possible to reduce the TMF of the original river water by two orders of magnitude.

As shown by studies on the processing of various liquid media, carried out using the installation 1 according to the present invention, due to the presence of the control electrode 5, it was possible to get rid of the streamer between the electrodes 4, 6 and expand the zone of impact of the discharge on the flow of the processed liquid medium over the entire cross section of the plasma discharge treatment zone, and also to increase the length of this zone, which directly affects the efficiency of liquid medium processing. This effect enhances the selection of the optimal geometric dimensions of all areas of the chamber 2, although it does not have to strictly correspond to the dimensions indicated above in the description.

Claims (14)

1. Device for processing a liquid medium, containing: a chamber in which an inlet diaphragm, a rod electrode, a control electrode and an annular electrode are arranged in series, the electrodes being configured to form a plasma that substantially evenly and completely occupies the volume of the housing between the rod electrode and the annular electrode; a diaphragm configured to provide a pressure jump at the inlet to the plasma region and thereby form a two-phase flow, including a liquid phase and a vapor phase, a diffuser installed on the side of the chamber, opposite to the location of the liquid medium inlet pipe, in which, by means of valves, a pressure is created higher than in the chamber to ensure condensation of the vapor phase of the two-phase flow; voltage on the rod electrode and ring electrode, and a control voltage generator for supplying voltage to the control electrode. 2. The device according to claim. 1, in which the control voltage generator is a constant voltage generator. 3. The device according to claim. 1, further comprising at least one gas supply channel installed in the area of the rod electrode. 4. The device according to claim. 1, containing an additional pin electrode in the area of the ring electrode. 5. A method for processing a liquid medium in a liquid medium processing device according to any one of paragraphs. 1-4, including: ensuring the flow of a liquid medium, formation of a supersonic two-phase flow of a liquid medium, processing a two-phase flow of a liquid medium in a plasma discharge, and increasing the pressure in the treated two-phase flow of the liquid medium to ensure the condensation of the vapor phase, while providing essentially complete coverage of the two-phase flow of the liquid medium by the plasma discharge. 6. The treatment method according to claim 5, further comprising supplying gas to the liquid medium stream.

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