RU2478580C1 - Device for decontamination of effluents by electric discharges - Google Patents

Abstract

FIELD: process engineering.

SUBSTANCE: invention relates to water treatment systems, particularly, to cleaning effluents with high content of organic matters by electric discharges for treatment of drinking water, industrial and domestic effluents, etc. Proposed device comprises housing with effluents inlet 2 and decontaminated water discharge outlet 3. Said housing represents reactor chamber 2 with means to feed magnetised air mix enriched in ozone and two coaxial central high-voltage electrodes 5, air duct 6 composed of metered lengthwise orifice inside one of said electrodes. High-voltage power supply 7 outputs pulses via power and frequency programmer and switchboard 8 to said electrodes.

EFFECT: reduced power consumption, high quality treatment.

8 cl, 1 dwg, 3 tbl, 2 ex

Description

The invention relates to water treatment and water treatment systems for domestic and industrial needs and can be used, for example, in various industrial fields for the treatment and disinfection of drinking water, wastewater from industrial and economic enterprises, medical organizations; sewage of small settlements. Specifically, the invention relates to devices for treating wastewater with a high content of organic substances by electric discharges.

A device for the purification of water (RU 2301776) containing a cathode and anode located on a dielectric tube connected to a control unit is known. Magnetic tablets are installed in the recesses of the cathode and anode. On the cathode nozzle there is a cap for collecting hydrogen and a valve for its removal. Such a device does not differ in the efficiency of water purification due to the low magnitude of the magnetic field to which water is exposed. An increase in tension modulus is not provided for in this invention. Here, the degree of water purification depends on the magnitude of the magnetic field strength, and when the intensity is small, then the purification is weak, ineffective.

A device is known for electrochemical treatment of water and aqueous solutions (RU 2374182), which contains coaxially arranged positive and negative electrodes, an ion-exchange diaphragm, coaxially placed between the electrodes, which divides the interelectrode space into chambers. In the device under consideration, the ion-exchange diaphragm between the electrodes is made in such a way, because of which the passage of water is delayed and the cleaning process is slow and ineffective.

A known method of cleaning liquid media (US 5130032), in which the material to be cleaned must first be accumulated and concentrated in a container from which it moves and undergoes electrostatic treatment, passes an ultrasonic ozone dispenser, an ultrasonic treatment chamber and a cooling unit. The process can be repeated several times until the required degree of oxidation is achieved, and hence the purity of the liquid. The disadvantages of this method include the multi-chamber cleaning process, the need for additional ozone supply, the need to lower the temperature at the last stage, and, accordingly, the low efficiency (high energy consumption) of cleaning liquids in this way.

A known method of water purification (application RU 2005124905) by the action of an electric barrier discharge on a mixture of water and an oxygen-containing gas, where the oxygen-containing gas is subjected to purification, cooling and introduced into the water directly in the discharge gap by dispersing through a porous electrode at an oxygen-containing gas pressure selected from the conditions of formation near a porous electrode of a thin gas layer in which an electric barrier discharge predominantly develops. In this method for water purification, water must be mixed with an oxygen-containing gas prior to the purification process, and also an oxygen-containing gas is additionally supplied to the discharge gap by dispersion. This is a rather complicated and expensive purification technology, since it is not practical to introduce an oxygen-containing gas into the water.

Known, for example, a method and apparatus for electroplasma wastewater treatment according to the application PCT / RU92 / 00006 (WO 92/12933, C02F 1/48). According to this method, before the water stream is fed into the reactor vessel, the stream is saturated with ozone-containing air, and after filling the reactor vessel, electroplasma discharges with an energy of at least 3 kJ per discharge and a frequency of 5 Hz are produced on the surface of the treated stream. The electric plasma arc formed during the discharge is moved along the surface of the water stream by a rotating electromagnetic field. The known method is carried out in a device containing a cylindrical container with nozzles for supplying and outputting a water stream and connected to different poles of the power source by a central electrode and an external ring electrode mounted on the upper edge of the container. The central electrode of the known device is equipped with a head that is in contact with the surface layer of the processed stream.

A known method and device for disinfecting water and saturating it with oxygen (LT5029), in which the device consists of a cylindrical "stator" equipped with air ducts, and a high voltage electrode pair ("rotor") connected to a generator of high voltage current pulses. The device can be used in storage tanks, however, it is unsuitable for flow systems, which is a significant disadvantage in comparison with the described invention. In addition, in the field of electrodes, due to field instability, more energy losses occur, it is less economical and its construction is more complicated in comparison with the device in the described invention.

It is known that the device for disinfecting water by electric discharges (SU 1263643), which includes a housing made in the form of a chamber with an air duct and a high-voltage pulse generator, a high-voltage electrode pair, the negative electrode of which is made of non-magnetic material and is equipped with holes for ozone supply to the electric discharge region, compressor.

The main disadvantages of the device include:

- dispersion of the ozone-air mixture in the zone of electric explosion, which leads to a sharp decrease in pressure and dissipation of the energy of discharge into the discharge zone;

- the need to include in the process of operation of the high-voltage pulse generator and the voltage generator as an additional energy source;

- the cost of a large amount of energy to heat the flow for the occurrence of a discharge;

- low service life of high-voltage insulators of the device and air gap, which wear out quickly due to the formation of destructive caverns at high currents and the simultaneous oxidation of metal as a material of the above components.

The problem to which the claimed invention is directed is to solve the problem of water treatment against the background of a deteriorating environmental situation as a result of pollution of the aquatic environment from the activities of industrial, agricultural enterprises and housing and communal services.

The technical result obtained by the implementation of the invention is to reduce energy costs during operation of the device without compromising the quality of wastewater treatment with a high content of organic substances.

The specified technical result is achieved due to the fact that the device for disinfecting wastewater with electric discharges contains a casing provided with openings for entering the cleaned drain and disinfecting water, made in the form of a reactor chamber with a supply of magnetized air mixture enriched with ozone and with a pair of high voltage coaxially located in the center electrodes with an air duct in the form of a calibrated longitudinal hole inside one of them, to which a pulse enters through the energy programmer and both frequencies and a switch from a high voltage power supply.

The use of the proposed device allows to reduce energy consumption by 10 times as a result of the effect of resonance from an electric explosion that occurs when a short pulse of a magnetized air mixture passes through a calibrated hole of a high-voltage electrode. The discharge occurs at the interface between the two water-air media, so the operation of the device no longer requires the inclusion of a voltage pulse generator and a current pulse generator. The initiating duct is performed in the negative electrode rod.

The energy entering the discharge zone in an amount not exceeding 50% of the energy stored in the capacitors of the high-voltage pulse generator (high-voltage power supply) guarantees the avoidance of polarity reversal in the energy storage devices (generator capacitors), due to which the service life of the high-voltage pulse generator capacitors is increased by 10 times in comparison with the considered analogues (an additional technical result is an increase in the durability of the device).

The energy stored by the high-voltage power source through the switch and the programmer is discharged into the interelectrode space (discharge zone), which ensures that the polarity of the energy storage devices (capacitors) is avoided, so that the life of the energy storage device (generator capacitors) is extended by 10 times or more compared to considered analogues.

Special cases of the device and its structural elements:

- the implementation of the input hole of the cleaned drain in the form of a Venturi pipe, passing from the outside into the reactor chamber and ending above the duct allows the flow to be in a suspended state and to swirl;

- the implementation of the means for supplying the air mixture in the form located inside the bottom of the chamber-reactor duct in the form of a spiral of Archimedes;

- execution of the damping space above the duct located at the bottom of the reactor chamber;

- the presence of a compressor equipped with a flow meter or flow restrictor;

- the implementation of the electrodes with a shell of dielectric material in the form of pointed rods provides the conditions for better drainage of energy (increases efficiency).

The magnetization of the air mixture entering the device housing can be carried out in electromagnetic activator devices. When connecting the input hole of the cleaned drain with the electromagnetic device-activator, the magnetization of the water flow (cleaned drain) occurs.

The reliability of the device increases (additional technical result), including when lowering the high voltage voltage on the electrodes from 50 kV (in the prototype) to 10-25 kV.

The high-voltage electrodes located inside the reactor chamber must be made of non-magnetic material (beryllium bronze, stainless steel, etc.) so that the electromagnetic field does not distort, the circuit inductance does not increase, the pulse duration does not increase, and the discharge power is big enough. The insulation coating of the high voltage electrodes used is made of a dielectric, for example polyethylene.

To clarify the essence of the claimed invention, it is proposed figure 1, which presents a structural diagram of the claimed device.

As information confirming the possibility of carrying out the invention with obtaining the above technical result, a description is given of the design of the device for disinfecting effluents in accordance with the claimed formula and the method of its operation.

The device comprises (Fig. 1) a casing made in the form of a technological chamber-reactor 1 with an inlet (inlet for input of the cleaned drain) 2 in the form of a venturi and an outlet (inlet for disinfected water) 3, with an air duct located inside the bottom of the chamber 4 in the form of a porous tube in the form of a spiral of Archimedes, with a pair of high-voltage electrodes 5, 5 'in the center, and the negative 5 electrode is made with an initiating duct 6, which is a calibrated hole inside it; high voltage power supply 7, which is an energy storage device, a generator of high voltage pulses; a high-voltage controlled switch 8, an energy and frequency programmer 9, a compressor (not shown), a flow meter (not shown), and electromagnetic activator devices 10 for magnetizing the water flow and the air mixture.

The inlet 2 of the reactor chamber 1, made in the form of a Venturi pipe to prevent sediment suspended matter from settling, ends above the air duct 4, at the base of the dielectric (insulation coating of the high-voltage electrode 5).

A damping space (not shown) is provided above the duct 4, which provides minimal pressure on the walls of the chamber-reactor 1 and protects the housing of the chamber-reactor 1 from deformation during discharge.

The reactor chamber 1 through the inlet is filled with a cleaned drain passing through electromagnetic activator devices 10 in which centrifugal acceleration is reported to the cleaned drain. Along with the drain, air enters the reactor, although the air enters the chamber from the inlet 1 (air does not interfere with the cleaned drain through the inlet 2). At the same time as the cleaned drain enters the process chamber-reactor 1 through the duct 4, and also into the discharge zone (interelectrode space) through the initiating (high-voltage discharge) duct 6 of the high-voltage electrode 5, it contains ozone containing a predetermined pressure (~ 5-7 atm) the air mixture that has undergone magnetic processing in the electromagnetic activator device 10. From the high-voltage power supply 7, through the energy and frequency programmer 9 (the energy and frequency of the discharges on the high-voltage electrodes 5, 5 'are set) and utator 8 is supplied pulse at high voltage electrodes 5, 5 '. The energy and frequency programmer 9, as well as the high-voltage controlled switch 8, can at any time stop access to the energy stored in the capacitors of the generator of the high-voltage power supply 7.

Impurities from the treated effluent under the action of centripetal force are constantly located in the area of the electrodes. The distribution of the air mixture from air ducts 3 and 4 in the reactor chamber 1 occurs under pressure (~ 1 atm) and is regulated by a flow meter and compressor.

The volume of the chamber-reactor for maintaining the pressure parameter and the functioning of the reactor is calculated so that the residence time in the reactor of the cleaned effluent enriched in the air mixture is at least 5 minutes: during this time, with the frequency set by the programmer 9, a discharge occurs in the interelectrode space and an electric explosion in the air-water the contents of the treated effluent, the wavelength of the oscillating particles of which is comparable with the geometry of bacteria. As a result of such an electric explosion, disinfection and purification of water occurs.

The air mixture in the electromagnetic device - activator 10, passes an alternating field, its magnetic treatment contributes to the creation of the dielectric heterogeneity, which is needed to localize the discharge in the right direction along a certain path, as well as to protect the insulation coating of the electrodes. Depending on the composition of the cleaned effluent entering the process chamber-reactor 1, the composition of the air mixture is varied so that its dielectric characteristics (dielectric constant ε ₂ electrical conductivity δ ₂ ) differ significantly from the corresponding dielectric constant ε ₁ , electrical conductivity δ _{1 of the} cleaned drain .

Wherein:

- for a weakly conducting fluid (when δ <0.02 Ohm ^-1 m ^-1 ) when pulses are fed into the interelectrode space, the time t between which t <10 ^-5 s, the dielectric constant is of decisive importance;

- for a strongly conductive fluid with a large time t between pulses, the conductivity is of decisive importance.

The composition of the air mixture can be varied in such a way that the discharge length in the interelectrode space increases from 45 mm to 90 mm, while the pressure in the process chamber-reactor 1 can reach 10,000 MPa.

The examples below show that the proposed device is suitable for treating waters with various physical and chemical characteristics (electrical conductivity, density, viscosity), since high temperature and pressure develop in the electroplasma, under the influence of which the molecular structure of any aqueous medium decomposes.

Example 1

Purification of runoff from pig manure, the moisture content of which is 100%, containing E. coli (Escherihia coli) and helminth eggs (Ascaris suum).

The discharge energy is 15 J, the temperature of the medium is t = 15 ° C, the gap is t = 5 μS, the air flow rate is 30% of the volume of the treated medium of the treated effluent.

Indicators Pulse frequency one 5 10 fifteen 25 The degree of disinfection of microorganisms in% 72 95 one hundred one hundred one hundred The degree of deworming in% 49 89 one hundred one hundred one hundred BOD (with an initial BOD of 49000 mg / l) 20000 6000 2400 1500 300 BOD (with an initial BOD of 49000 mg / l, an ozone-air mixture of 10% ozone per 1 liter of air is supplied to the discharge zone) 10,000 2000 800 300 240

Example 2

Cleaning the waste stream of a meat factory, the pH of the crude runoff is 6-8, the dry residue is 200-2000 mg / l, permanganate oxidation is 84-540 mg O / l, COD 240-900 mg / l, fats 240-5000 mg / l, oil products 2- 200 mg / l, phenol 0.01 mg / l, ammonium nitrogen 10-70 mg / l.

Indicators Slaughterhouse waste flow rates after processing in the device Discharge energy 10 J, pulse frequency 10 Hz Discharge energy 15 J, pulse frequency 10 Hz pH 7.5 8.0 The dry residue, mg / l 75 75 Permanganate oxidation, mg / l 80 80 COD, mg / l 140 80 Fats, mg / L 44 10 Oil products, mg / l 0.5 0.02 Phenol, mg / L 0.01 - Ammonium nitrogen, mg / l 3.0 3.0

Example 3

Cleaning of galvanic drains. Debit Q = 5 m ³ / h, discharge energy 15 J, frequency 10 Hz, residence time of the stream in the reactor 10 minutes.

Show
whether Sample data (1 - initial cleaned stock, 2 - output data) one 2 one 2 one 2 one 2 Chromium 0,043 Not an update 0,028 0.001 1,2 0.4 1.8 1,2 Zinc 0.94 0,099 0.94 0.058 6.1 0.99 7.8 1,2 Molybdenum 0.4 Not an update 2.7 0.64 5.2 2,56 8.0 4.4 Nickel 0.08 0,032 1.3 0.2 4.4 0.87 7.5 1,0 Iron 0.96 0.42 1,6 0.42 10.5 7.8 13,4 5.3 Copper 0.8 0.44 0.8 0.1 No given. No given. No given. No given. pH 1,5 5.5 1,5 6 1,5 2,5 1,5 2.0

Claims (8)

1. Device for disinfecting wastewater with electric discharges, characterized in that it contains a housing provided with openings for entering the cleaned drain and disinfecting water, made in the form of a reactor chamber with means for supplying magnetized air mixture enriched with ozone and with a pair of high-voltage electrodes coaxially located in the center of the chamber with an air duct in the form of a calibrated longitudinal hole inside one of them, the impulse to which comes through an energy and frequency programmer and a switch from juice supply. 2. The device according to claim 1, characterized in that for the magnetization of the air mixture, electromagnetic activator devices are used. 3. The device according to claim 2, characterized in that the electromagnetic activator device is connected to the input hole of the cleaned drain. 4. The device according to any one of claims 1 and 2, characterized in that the amount of energy entering the discharge zone does not exceed 50% of the energy stored in the capacitors of the high voltage power source. 5. The device according to any one of claims 1 and 2, characterized in that the input opening of the cleaned drain is made in the form of a venturi. 6. The device according to any one of claims 1 and 2, characterized in that the means for supplying the air mixture is an air duct located inside the bottom of the reactor chamber in the form of an Archimedes spiral. 7. The device according to any one of paragraphs.1 and 2, characterized in that it further comprises a compressor equipped with a flow meter or air flow restrictor. 8. The device according to any one of claims 1 and 2, characterized in that the voltage at the electrodes is 10-25 kV.