WO2022235249A1

WO2022235249A1 - A method for purifying a contaminated water

Info

Publication number: WO2022235249A1
Application number: PCT/UA2021/000066
Authority: WO
Inventors: Mariia Oleksandrivna MYKYTIUK
Original assignee: Mykytiuk Mariia Oleksandrivna
Priority date: 2021-05-06
Filing date: 2021-07-22
Publication date: 2022-11-10

Abstract

The invention relates to a method for purifying a contaminated water. The method has been developed for purifying a contaminated water by means of a system comprising a detection unit, a control unit, and a purification unit which are operatively connected between each other, the method comprises the following steps of determining values of parameters of the water being purified by means of the detection unit, transmitting a data about the values of the parameters of the water being purified to the control unit, creating a water purification scenario that determines at least a portion of purification operations available for performing by the purification unit, their modes and sequence, to achieve a compliance of the values of the water parameters with given requirements by means of the control unit based on the received data, purifying the water by means of the purification unit that is controlled by the control unit according to the created scenario, wherein, as the purification unit, a set of equipment is used which is configured to perform purification operations based on various specific processes. The developed method enables purification of contaminated waters having a qualitative and a quantitative formulation of contaminating agents that varies within a wide range until the compliance of values of parameters of said waters, i.e. of their quality, with given requirements with minimum energy, time costs and consumption of reagents.

Description

A METHOD FOR PURIFYING A CONTAMINATED WATER

The invention relates to a method for purifying a contaminated water, e.g., industrial wastes or a filtrate of solid domestic waste landfills, and it may be used to bring the water that is fed for purification into compliance with certain requirements, preferably, with the requirements of state standards and sanitary legislation as to drinkable water, in terms of organoleptic, physical and chemical, microbiological, parasitologic, and radiation parameters.

Generally, purification of the contaminated water is a method for preparing the water in order to enhance parameters of its quality. The prior art teaches various purification methods which may be performed utilizing mechanical, chemical, physical, and biological purification methods depending on a qualitative and a quantitative formulation of contaminating agents which may be organic and inorganic substances having various properties, as well as pathogenic and potentially pathogenic microorganisms (e.g., clarification, softening, desalination, deferrization etc.).

Therewith, patent of Ukraine No. 99811 discloses a method of water treatment to provide a purified water from a supply water comprising a dissolved substance, the method comprises supplying the supply water to at least one treatment surface that comprises a semipermeable membrane and pressurizing the supply water in order to cause a reverse osmosis flow of the purified water through the membrane, wherein the semipermeable membrane is equipped with an electrically conductive element or an electrode is arranged in the vicinity thereof, creating an electrical field on the electrically conductive element or on the electrode by supplying an electrical voltage, and forming a hydration water layer that is discharged by forcing it to flow through the membrane under the pressure of the supply water.

A drawback of this method is a presence of a large-volume concentrate that does not pass through the semipermeable membrane, is not purified, and is not discharged. A further drawback of this method is a blockage of the semipermeable membrane with mineral deposits which must be removed periodically using chemical solutions which form an additional volume of repeatedly contaminated water. Patent of Ukraine No. 89835 discloses a method for purifying a water from disperse impurities under clarification of natural and waste water by a coagulant treatment, magnetic treatment, and electric coagulation. The electric coagulation is conducted under constant stirring with a linear rate of from 0.5 to 1.5 m/sec within from 30 to 150 sec.

This method is suitable merely for purification of the water mainly from non-dissolved compounds comprised therein. This method does not remove the dissolved and organic compounds are not removed from the contaminated water. A further drawback of this method is a repeated contamination of the water with metal ions of electrodes when performing the same. Such water requires further purification.

Patent of Ukraine No. 82300 discloses a method for purifying water from hard metals, the method comprises filtration thereof through a porous titanium filtration element that is arranged in an electrical field. The filtration is performed under a simultaneous water flow along a surface of the filtration element with a volumetric rate of from 18 to 27 dm³ per hour under a flow density of from 44.8 to 74.6 A/m².

A drawback of this method is impossibility of removal of other contaminating substances, e.g., organic compounds, from the water except for the hard metals. A further drawback of this method is an accumulation, with time, of mineral deposits within the porous electrode and its blockage. Washing the porous electrode in order to dissolve the mineral deposits creates a significant volume of a repeatedly contaminated water in addition to a concentrate that does not pass through the porous electrode.

Patent of Ukraine No. 82816 discloses a method for purifying a contaminated water by means of an electroerosion coagulation, the method comprises operations of passing an aqueous solution through a layer of metal granules which are arranged in a flash chamber and which are exposed to electrical impulses to form a coagulant, destroying the granules under action of spark discharges, settling the aqueous solution and filtration, wherein the initial aqueous solution is divided into two fractions prior to passing through the layer of metal granules, creating an acidic medium in the first fraction and an alkaline medium in the second fraction, then each fraction is passed through a separate flash chamber with the layer of metal granules, afterwards the acidic fraction is forwarded to a repeated purification cycle and mixed with the initial aqueous solution, and the alkaline fraction is settled.

A drawback of this method is an impossibility to remove contaminating organic substance from the water and to destroy them. A further drawback is a release of ions and metal nanoparticles which constitute the metal granules arranged in the flash chamber into the water to be purified, thereby leading to a need in an additional purification of such water. A further drawback is a reduced energy efficiency of the process (at least 50% reduction) due to conduction of the additional treatment of the acidic fraction of the water with the spark discharges.

Patent of Ukraine No. 77676 discloses a method for purifying a water which comprises treating thereof with electrical discharges which are formed in the water between discharge electrodes when the water to be treated flows through openings, wherein the electrodes are divided by a dielectric diaphragm with openings and a discharge is created in the openings, thereby supplying a voltage to the electrodes from an electric energy source. The voltage of a direct or an alternating or impulse currents is used.

A drawback of this method is an impossibility to purify a water that is contaminated with organic substances. A further drawback is a low performance of the method due to a small volume of the created discharges.

Patent of Ukraine No. 122318 discloses a method for purifying a ballast water which comprises introducing an oxidizing agent therein followed by treatment with an ultraviolet irradiation, wherein the ballast water is treated with sodium hypochloride that is introduced in amount of from 0.2 to 0.4 g/dm³ and with iron chelate that is introduced in amount of from 8 to 9 g/dm³, afterwards the ballast water treated in such way is filtered through a coarse mesh filter, is exposed to the ultraviolet irradiation, high-frequency electrohydraulic impact by alternating impulses having a duration of from 10 to 6 sec under an instantaneous impulse power of from 50 to 1000 MWt and further filtration using a self-dumping fine mesh filter. Main steps of this methods are mainly aimed at decontamination of the water. Therefore, the water is not purified from ions and molecules of dissolved compounds.

Patent of Ukraine No. 22571 discloses a method for purifying a water from chemical compounds and biological impurities, the method comprises hydrodynamic cavitation, electrical coagulation of the water using, e.g., aluminum electrodes to form aluminum hydroxide on which particles located in the water are settled, and they are removed from the water by means of settling or filtration. After said particles are removed from the water, a passive cavitation of the water is performed that is an oxygen aeration, thereby destroying chemically bond groups by oxidizing them with oxygen.

A drawback of this method is its increased energy consumption that is caused by a need to use oxygen as the oxidizing agent, thereby requiring to use an equipment for generating oxygen from air. A further drawback of this method is an impossibility to purify the contaminated water having a high concentration of organic substances. Presence of the high concentration of organic substances in the water will require a multiple treatment of the water in a cavitation apparatus with oxygen that will lead to use of a large volume of oxygen and, thus, increase of the energy consumption. A further drawback of this method is a release of ions of an anode metal to the water to be purified that will lead to a repeated contamination of the water and to a need to use an additional equipment to remove said ions.

Therefore, as it is seen from the above-mentioned description, the drawback that is common for all the analogues is associated with the impossibility to purify the contaminated water that is characterized by various or variable qualitative and quantitative formulation of the contaminating agents.

The European application EP3666734 discloses a method for purifying a ballast water selected as a prototype by means of a system that comprises a detection unit, a control unit, and a purification unit which are operatively connected between each other. According to said method, values of parameters of the water that is supplied for purification are determined by means of the detection unit. Said data is transmitted to the control unit that, based thereon, creates a water purification scenario to achieve the compliance of the values of the water parameters with given requirements. Afterwards, the water is purified by means of the purification unit that comprises a corresponding equipment and that is controlled by the control unit according to the created scenario.

Although said method considers the values of the parameters of the contaminated water and implies generating of the scenario for further treatment based on said data, the application text lacks a description of specific processes with their modes that underlie the operations being performed, except for mentioning them in the most general form. Therefore, said method may be characterized with the drawbacks which characterize the above-disclosed analogues.

A task of the claimed invention lies in developing a method for treating a contaminated water that could enable to achieve a technical effect that lies in enabling purification of contaminated waters having a qualitative and a quantitative formulation of contaminating agents that varies within a wide range until the compliance of values of parameters of said waters, i.e., parameters of their quality, with given requirements, preferably, with requirements of a drinkable water standard, is achieved with minimum energy, time costs and consumption of reagents.

The posed task is resolved by developing a method for purifying a contaminated water by means of a system comprising a detection unit, a control unit, and a purification unit which are operatively connected between each other, the method comprises the following steps of: determining values of parameters of the water being purified by means of the detection unit, transmitting a data about the values of the parameters of the water being purified to the control unit, creating a water purification scenario that determines at least a portion of purification operations available for performing by the purification unit, their modes and sequence, to achieve a compliance of the values of the water parameters with given requirements by means of the control unit based on the received data, purifying the water by means of the purification unit that is controlled by the control unit according to the created scenario, wherein, as the purification unit, a set of equipment is used which is configured to perform purification operations which are based at least on processes of: a) destroying hydration shells of ions and/or molecules of the contaminating agents under influence of the energy of cavitation processes followed by transformation of the released ions and/or molecules into molecules of insoluble compounds at a pH higher than 9.0; b) destroying hydration shells of ions and/or molecules of the contaminating agents under influence of the energy of cavitation processes followed by formation of molecules of complex compounds from the released ions and/or molecules and sorption of the molecules of complex compounds by a preliminary added sorbing agent at a pH of between 5.0 and 9.0; c) destroying the hydration shells of the ions and/or molecules of organic and inorganic contaminating agents under influence of the energy of the hydrated electrons and hydrogen ions followed by reduction and/or cleavage, and/or dissociation of the released ions and/or molecules and formation of the complex compounds having surfactant properties at a pH of between 5.0 and 8.0 from the obtained ions and/or molecules; d) destroying the hydration shells of the ions and/or molecules of the contaminating agents under influence of the energy of the hydrated electrons, hydrogen ions, and water electrolysis products followed by reduction and/or cleavage, and/or dissociation of the released ions and/or molecules and sorption of the obtained particles by the contaminating agents in the form of preliminary coagulated organic substances at a pH of between 2.0 and 3.0; e) destroying hydration shells of ions and/or molecules of the contaminating agents under influence of the energy of the hydrated electrons followed by transformation of the released ions and/or molecules into molecules of complex insoluble compounds at a pH of between 9.0 and 11.0; f) destroying the hydration shells and the contaminating agents under influence of the energy of cavitation processes and/or energy of the hydrated electrons, and/or energy of the water electrolysis products followed by sorption of the released ions by the preliminary formed complex insoluble compounds; g) destroying the molecules of the organic compounds of the contaminating agents by a full oxidation under influence of the energy of the hydrated electrons and water electrolysis products until a state of carbon dioxide at a pH of between 3.0 and 5.0; h) decontaminating the water being purified under influence of the hydrated electrons and water electrolysis products; i) separating the contaminating agents from the water being purified.

Essentially, the contaminated water may be a regular solution, a colloidal solution, a suspension or any combinations thereof simultaneously (i.e., comprising particles of the contaminating agents in the form of ions, molecules, their aggregates in the form of micelles and solid particles of insoluble substances).

It is known that ion of the contaminating agents interact with water molecules via electrostatic fields. This interaction leads to formation of one or more layers of the water molecules around each ion. Such water is a bound water. Therefore, the higher the concentration of ions in the water is, the larger portion of the water molecules is bound. Therewith, the higher the surface density of the ion charge is, the stronger a screen of the molecules of the hydrated water is.

In such a way, ions which have a high density of the surface charge, e.g., Li⁺, Na⁺, Mg⁺, Al³⁺, Fe³⁺, Cr³⁺, F , Cf, C03² , HCO3 , strongly interact with molecules of the bound water and are characterized by a positive hydration that is characterized by sealing of molecular complexes formed by hydrogen bonds. Polyvalent cations, e.g., Al³⁺, Fe³⁺, Cr³⁺, have the strongest bonds with the hydrate water molecules and form covalent bonds of complex compounds |A1 (H2q)ό|³⁺, |Fe(H₂0)6|³⁺, |Cr(H₂0)₆|³⁺ with them. Ions having a low surface charge density, e.g., K⁺, Cs⁺, NI¾⁺, G, Br , HPO4² , H₂PO₄ , NO₃ , CIO₄ , have a weak bond with the hydrate water molecules, are characterized by a negative hydration, and facilitate reduction of the density of the molecular complexes formed by the hydrogen bonds.

Therewith, if the concentration of ions in the water is high constituting 1 mol/1 and higher, almost entire water is bound. While if polyelectrolytes, e.g., proteins, nucleic acids or other soluble organic substances, are present in the water and when the concentration of such substances is lower than 1 mol/1, the entire water will become bound.

The bound water, i.e., the layer or layers of the water molecules formed around the ion, neutralizes the electrostatic field of the ion and makes a formation of covalent bonds of the ion with other ions, i.e., formation of molecules by them, impossible.

Molecules of the dissolved substances comprised in the water, as well as the ions, are covered with at least one layer of molecules of the water that is bound to them. As opposed to the ions, the molecules have areas with different polarities. The polarity of a certain area of the molecule being positive or negative causes the corresponding orientation of the adjacent water molecules oriented by the opposite polarity, while the positive polarity of the area of the molecule of the dissolved substance causes the orientation of the adjacent water molecules by the negatively charged pole. Layers of the water molecules which are formed around the molecules of the dissolved substances interfere a conduction of chemical reactions of oxidizing the molecules and their destroying during the water purification process. The larger size of the molecules of the dissolved substances is, the larger is the size of the layers of the water molecules which surround them. Thus, such hydrated molecules hold a significant amount of water.

Micelles of the contaminating agents comprised in the water are also covered with at least one layer of molecules of the water that is bound to them. The layer of the water molecules that surrounds each micella avoids association of several micelles into a larger structure. Therefore, almost all molecules of heavily contaminated water having the concentration of the contaminating substances of 1 mol/1 and more are bound and form layers of molecules around the contaminating agents in the form of ions of the dissolved substances, micelles of colloidal substances, and molecules of organic compounds.

Separation of said ions, micelles, and molecules from the water molecules surrounding them by means of baromembrane methods is a rather energy- consuming process. Almost the entire bound water does not pass through the reverse osmosis or ultrafiltration membrane, thereby causing an increase of the concentrate volume in the course of increase of the concentration of the contaminating substances in the water. This is explained by the fact that all water molecules are bound by highly energetic covalent bonds to ions, micelles, and molecules of the contaminating agents. Such structures have a size that is significantly greater than a diameter of pores of membranes, thus, they do not pass through the membrane. Therewith, the bond between the ion or molecule of the contaminated substance and molecules of the bound water is covalent, i.e., it is highly energetic. Destruction of such bonds requires a power that is created by a high pressure of the solution from one side of the membrane. The higher the concentration of the dissolved substances is, the higher pressure is required to be created to separate the bound water molecules from the ions and/or molecules, and/or micelles of the dissolved substances.

The above-described processes a)-g) which the purification operations are based on and which may be performed by the set of equipment of the purification unit enable freeing, for a certain rather short term, of ions, molecules, and micelles of the contaminating agents from their shells formed by the water molecules, create favorable conditions, preferably, due to correction of the pH level, which enable the free ions and molecules, loosing the neutralizing layer of the water molecules that avoids their coupling to each other, to combine, thereby forming molecules of insoluble and complex compounds which may be separated in such a way from the water being purified with insignificant energy, time costs and consumption of reagents. Furthermore, all the processes which serve as a basis for the purification operations, i.e., the processes a)-i), are selected so as to enable purification of the contaminated waters having qualitative and quantitative formulation of the contaminating agents that varies within a wide range until the compliance of the values of parameters of said waters, i.e., parameters of their quality, with the given requirements is achieved. Therefore, the contaminated water that may be purified by the inventive method may be characterized by a complex contamination, contamination with heavy metals, contamination with one or two contaminating substances of an inorganic nature, contamination with one or two contaminating substances of an organic nature, contamination with a wide spectrum of substances of organic and inorganic nature, contamination with biogeneous elements, contamination with resistant organic compounds etc.

The hydration shells, according to the invention, are destroyed under influence of the energy of cavitation processes, water electrolysis products, and hydrated electrons.

The hydrated electrons are strong reducing agents having a potential of -2.87 V. The hydrated electrons are characterized by reactions of three types, namely, addition to ions, e.g., Cu²⁺ +e_aq = Cu⁺, Cu⁺ +e_aq=Cu, addition to neutral molecules, e.g., O2 +e_aq = O2, and a dissociated addition, e.g., N2O +e_aq=N₂+0*. Most of the reactions which involve the hydrated electrons have a high reaction rate.

Also, the hydrated electrons may be generated under influence of the electromagnetic fields at a separation of phases metal-electrolyte. The electron exits the metal, passes the separation of phases metal-electrolyte, and is added to an acceptor that is located in the electrolyte. This is a general overview of the generation of the hydrated electrons on a cathode. The electron transfer from the metal to the acceptor changes the charge of the latter, thereby leading to a rearrangement of the structure and orientation of the water molecules which surround the acceptor.

The cavitation processes which are generated in the water being purified locally generate powerful energetic flows which destroy the hydration shells around the ions, molecules, and micelles, and activate conduction of various chemical reactions. The activation of chemical reactions under conditions of the cavitation processes is caused by (1) separating the ions and molecules from the hydration shells which were blocking the conduction of reactions in which they were participating; (2) introducing an additional energy into the system, the energy being necessary for the conduction of reactions which require an external energy for their implementation; (3) intensive mass exchange that accelerates the conduction of the reaction and a degree (a completeness) of their conduction; (4) generating strong oxidizing agents such as hydrogen peroxide from the water molecules which enter into secondary reactions with the ions and molecules of the dissolved substances.

Water electrolysis products, preferably, OH , H2O2, are strong oxidizing agents. They are formed at the separation of phases electrode-solution from the water molecules under influence of the external electromagnetic field. The process of generating the water electrolysis products is closely related to the process of generating the hydrated electrons both spatially and over time. The efficiency of the process of generating the water electrolysis products depends on many conditions, including (1) a material of the electrodes, (2) pH of the solution, (3) a flow density on the surface of the electrodes, (4) presence or absence of a membrane between the electrodes, (5) the mass exchange rate of the solution near the surface of the electrodes, (6) a concentration and a nature of the dissolved substances.

In the text of the present description and claims, the contaminating agents which are separated from the water being purified by means of the operations based on the process (i) mean contaminating agents which are comprised in the contaminated water that is supplied for purification and do not require destruction of the hydration shells (e.g., solid particles of insoluble substances), as well as contaminating agents formed from previous contaminating agents as a result of performing the water purification according to one or several operations which involve said destruction of the hydration shells.

The purification processes which serve as a basis for the purification operation are defined by the scenario, may be conducted simultaneously, i.e., combined spatially and over time, or successively in the same or different equipment which depends on a content of particular processes. In this way, for example, the processes a) and b) may be performed simultaneously, since they occur under influence of the cavitation; in a single equipment, for example, the processes d) and c) may be performed successively by adding pH-increasing reagents; in different equipment, for example, the processes d) and i) or e) and i) may be performed which constitute in association and separation of the contaminating agents.

A set of sensors which include at least pH, turbidity, and electric conductivity sensors is used as the detection unit comprised in the system that implements the inventive method. It is obvious that any sensors which provide data suitable for the purposes of creating the water purification scenario to bring the values of its parameters into compliance with the given requirements may be used in addition or instead.

Most preferably, the determination of the values of the water parameters is performed continuously, while if the values of said parameters are changed as compared to their previous values, the water purification scenario will be changed in a real time.

Preferably, the hydrated electrons and ions of hydrogen are generated on titanium electrodes under influence of the electromagnetic field having an alternating force and a voltage of between 5 and 2000 V and a direct current density in the range of between 5 and 300 mA/cm². Such wide range of the mode for carrying out the processes enables to purify the contaminated waters having a qualitative and a quantitative formulation of the contaminating agents that varies within a wide range.

Any equipment that is available at the current state of the art may be used as the equipment that is required to performed the purification operations according to the claimed invention. Particular examples of such equipment together with a detailed description of examples of a particular set of the purification operations which may be performed during implementation of the claimed method using said equipment are mentioned below. Said particular set of the operations that is mentioned below, in spite of the higher number of operations comprised therein as compared to the number of the described processes a)-i), is completely described by said processes a)-i) which are therefore mentioned in a more generalized form.

Thus, the particular set of the purification operations which may be performed during implementation of the claimed method may include Operations 0-12.

According to the Operation 0, the contaminating agents in the form of solid particles having a size of more than 1 millimeter are separated from the water being purified by means of the coarse mesh filter. The Operation 0 is based on the process i).

According to the Operation 0, the contaminating agents in the form of organic substances which are prone to concentrate on the separation of phases liquid-gas are separated from the water being purified. Hydrogen that is generated on electrodes is used as a gas that creates a large area of the separation of phases liquid-gas. Hydrogen bubbles are stable over time, and their concentration in the water being purified increases over time, thereby enlarging the area of the separation of the phases liquid- gas, wherein the corresponding contaminating agents are concentrated in a foam. Hydrogen generation occurs at the direct current voltage in the range of between 3 and 15 V, wherein the voltage is regulated automatically depending on the electric conductivity of the water being purified so as to maintain the density of the current force on the electrodes between 5 and 20 mA/cm². During performing of the Operation, the organic compounds which contact the anode surface are oxidized, the organic compounds which remained in the water after its passage through the electrolyzer are oxidized with water electrolysis products, while the water being purified is decontaminated under influence of the impact on the corresponding contaminating agents by the water electrolysis products and hydrated electrons. Said Operation is performed using an electric flotation unit having electroerosion-resistant electrodes, wherein the flow of the water being purified passes within an interelectrode space, as well as a generator of direct current impulses having a voltage of between 3 and 20 V. The Operation 1 is based on the processes c), i), h).

According to the Operation 2, the acidity of the water being purified is reduced up to pH 2.5 by adding an acid, colloidal compounds which coagulate under these conditions are separated from the flow of the water being purified, the water separated from the colloidal compounds is decontaminated under influence of the water electrolysis products and hydrated electrons. In order to separate the coagulated organic substances from the water, bubbles of gas, namely hydrogen, are used. A membraneless electrolyzer is used as a hydrogen source. The acidity level is corrected automatically by adding the acid, wherein the selection of the acid depends on a chemical formulation of the contaminating agents in the water being purified. Addition of the required volume of the acid in order to reduce the acidity level of the water being purified up to pH = 2.5 is regulated by a pH sensor. Preferably, the bubbles which are formed by hydrogen have a size of between 0.1 and 0.3 mm. Hydrogen generation is performed at the direct current voltage in the range of between 3 and 15 V, wherein the direct current voltage is regulated automatically depending on the electric conductivity of the water being purified so as to maintain the density of the current force on the electrodes between 5 and 20 mA/cm². During performing of the Operation, the organic compounds which contact with the anode surface are oxidized, while the organic compounds which remained in the water after its passage through the electrolyzer are oxidized by the water electrolysis products. The decontamination of the water being purified is performed under influence of the water electrolysis products and hydrated electrons. Said Operation is performed using an electric flotation unit coupled to an acid dosing unit, wherein the flow of the water being purified passes within an interelectrode space, a generator of direct current impulses having a voltage of 20 V, and a press filter. The Operation 2 is based on the processes d), i), h).

According to the Operation 3, the pH level of the water being purified having the pH in the range of between 2.5 and 8.0 is increased up to the level of between 9.0 and 9.5 by adding alkali, conduction of the chemical reactions is initiated with formation of insoluble compounds by generating cavitation processes in the water at the pH of 9.0. Said Operation is performed using an electric flotation unit coupled to an alkali dosing unit, a generator of direct current impulses having a voltage of 20 V, and a press filter. Then, the formed residue is separated from the flow of the water being purified, water alkalinity is increased from pH 9.0 - 9.5 to 10.5 - 11.0 by adding alkaline and the conduction of the chemical reactions is initiated to form the insoluble compounds by generating the cavitation processes in the water at pH 10.5 - 11.0 and the formed residue is separated from the flow of the water being purified. Said Operation occurs using a reactor, a container coupled to a cavitator, dry substances dosing unit, and a press filter. The alkalinity of the water that is supplied for purification is corrected automatically by adding the alkaline. The volume of the alkaline being added is corrected in an automatic mode by pH sensors. In order to mix the water being purified, bubbles of the air that is supplied to a lower portion of the reactor are used. The solid residue is separated on the press filter having a resolution of 10 microns. The Operation 3 is based on the processes a), b), e), f), i), h).

According to the Operation 4, the insoluble and colloidal compounds and microorganisms are separated from the water being purified on a ceramic membrane. Bacteria, microalgae, and other microorganisms are inactivated during contact with the ceramic membrane that comprises oxides of bactericidal metals. Layering of mineral substances on a surface of the ceramic membrane and bacteria on inner walls of the filter are separated and inactivated accordingly by means of ultrasonic oscillations which generate the cavitation processes in the water. Said Operation occurs using the filter with the ceramic membrane. The resolution of the ceramic membrane is 0.1 microns, the membrane operates with the pressure in the range of between 0.5 and 4 atmospheres and possesses antibacterial properties. Under these conditions of conduction of the Operation, the membrane surface after its processing is not coated with organic layerings at least during eight months of permanent presence in the aqueous medium. Preferably, the filter is equipped with a purification system that is one or several ultrasonic generators. Purification of the ceramic membrane occurs without water passage, thereby reducing the water volume that is required to purify the membrane surface from layerings of mineral substances. The Operation 4 is based on the processes f), i).

According to the Operation 5, the organic and inorganic compounds which are adsorbed on a surface of sorbing agents are separated from the flow of the water being purified during passage of the water through a thin sorbing agent layer having a thickness of between 50 microns and 3 mm applied on the ceramic membrane. Said Operation occurs using the filter with the ceramic membrane, the filter is coupled to the cavitator and to the dry substances dosing unit. The ceramic membrane is characterized by the resolution of up to 1 micron, operates with the pressure in the range of between 0.1 and 4 atmospheres, is coated with the sorbing agent layer having a thickness in the range of between 50 microns and 3 mm. Formation of the sorbing agent layer on the ceramic membrane occurs during filtration through the membrane of the aqueous suspension of this sorbing agent, while the concentration of the sorbing agent in the suspension is in the range of between 0.1 and 1 g/1. The concentration of the sorbing agent in the suspension does not depend on the concentration of the contaminating agents in the water being purified. A mass of the sorbing agent that is supplied to the filter in order to form an additional layer on the surface of the ceramic membrane is controlled automatically, wherein the supply of the sorbing agent to the ceramic membrane of the filter is terminated automatically when the pressure on the membrane of the filter is increased above 0.5 atmospheres. After the sorbing agent layer is formed on the surface of the ceramic membrane, the sorbing agent is not added to the flow of the water being purified. The existing sorbing agent layer is replaced with a new one during passage of the contaminating agents which are separated on the filter through the membrane of the filter after purification of the membrane surface by means of the ultrasonic oscillations. Purification of the surface of the ceramic membrane from the existing sorbing agent layer is performed without passage of the water through the filter. After purification of the surface of the ceramic membrane, the water volume that equals to a volume of the space between the wall of the filter housing and the ceramic membrane is supplied to the filtration on the press filter having a resolution of 1 micron, and after the press filter has been passed, it is mixed with the flow of the water being purified. The filter with the ceramic membrane is equipped with a purification system that is one or several ultrasonic generators. The Operation 5 is based on the processes f), i).

According to the Operation 6, the organic substances in the flow of the water being purified is decomposed and oxidized on the anodes which are destroyed under influence of the electrochemical erosion. The Operation is performed in the range of the water pH of between 3.0 and 5.0. The pH level of the water being purified is corrected automatically by adding the acid, wherein the selection of the pH level and the selection of the acid depends on chemical properties of the contaminating agents in the water being purified. The Operation is performed with supply of the direct current having the voltage in the range of between 3 and 20 V to the electrodes. The voltage is regulated automatically and controlled by the electric conductivity of the water being purified. The voltage is regulated in order to maintain the current force density on the electrodes in the range of between 200 and 300 mA/cm², wherein the density depends on the qualitative and the quantitative formulation of the contaminating agents in the water being purified. The decontamination of the water occurs under influence of the water electrolysis products and hydrated electrons. The residue is separated from the water being purified on the filter having a resolution of 10 microns. Said Operation occurs using a reactor having the membraneless electrolyzer, wherein the water being purified circulates within the interelectrode space, as well as a generator of direct current impulses having a voltage of between 3 and 20 V. The anode is made of carbon steel or aluminum alloy, the cathode is made of stainless steel. The water being purified is supplied at a rate in the range of between 0.3 and 1 m/sec in the interelectrode space. The water in the electrolyzer circulates in a closed-loop fashion for 1 - 10 mins. The Operation 6 is based on the processes g), h).

According to the Operation 7, the organic and inorganic compounds are oxidies during conduction of the most of the chemical reactions which are initiated under influence of a cold plasma energy. Discharges of the cold plasma generate flows of the hydrated electrons, strong oxidizers from the water molecules, namely, OH-, H202, O*, ultrasonic waves, and ultraviolet radiation. Chemical reactions result in a formation of oxides and hydroxides of metals and their complex compounds having a developed surface which the organic and inorganic compounds are adsorbed on. The water being purified is decontaminated under influence of the water electrolysis products, hydrated electrons, ultrasonic and ultraviolet radiations, and oxides of bactericidal metals. Solid compounds are separated from the flow of the water being purified. Said Operation occurs using a flow reactor for forming the cold plasma in the water flow, a generator of the direct current impulses having a voltage of up to 2000 V. The plasma formation is performed in a ferrous or aluminum or copper medium under influence of the direct current discharges having a voltage in the range of between 500 and 2000 V. The direct current force in the impulse is 1.0 - 1.5 A, a frequency of the direct current impulses is in the range of between 10 and 50 Hz. Separation of the solid and colloidal substances formed during purification of the water being purified is performed on the filter with the ceramic membrane having the resolution of up to 1 micron under pressure of between 0.5 and 4 atmospheres. The Operation 7 is based on the processes e), f), h).

According to the Operation 8, the organic compounds are decomposed and oxidized on the surface of the anode being resistant to the electrochemical erosion and water electrolysis products in the anode chamber at a pH of between 2.5 and 5.0. Oxidization of the organic compounds in the anode chamber is performed at the direct current force on the anode within the range from 5 to 200 mA/cm², wherein the current force density on the anode depends on the qualitative and quantitative formulation of the organic substances to be oxidized. The Operation is performed at the direct current voltage of between 3 and 15 V. The voltage is corrected automatically by parameters of the water being purified, namely, by its electric conductivity, wherein the correction is performed automatically so as to maintain the current density on the anode of not more than 200 mA/cm². The decontamination of the water being purified is performed under influence of the water electrolysis products and hydrated electrons. Said Operation is performed using a membrane electrolyzer and a generator of direct current impulses having a voltage of up to 20 V. A titanium anode having a coating of rhutenium or another known material being resistant to the electrochemical destruction is used as the anode. The electrolysis process is performed by the direct current in the impulse mode that inhibits formation of a layer of oppositely charged ions that leads to reduction of the mass exchange between the electrode surface and the water being purified and to reduction of the electrolyzer operation efficiency. The Operation 8 is based on the processes g), h).

According to the Operation 9, the metal ions are reduced on the cathode surface by the hydrated electrons, the reduced metals are oxidized by the water electrolysis products in the cathode chamber at a pH of between 9.0 and 10.5 to form the insoluble compounds, the water being purified is decontaminated under influence of the hydrated electrons, water hydrolysis produces, and oxides of the bactericidal metals. Oxidization of the metal ions in the cathode chamber is performed at the direct current force on the cathode within the range from 5 to 200 mA/cm²; wherein the current force density on the cathode depends on the chemical formulation and concentration of the substances to be oxidized. The Operation is performed at the direct current voltage of between 3 and 15 V, wherein the voltage is corrected automatically by parameters of the water being purified, namely, by its electric conductivity, so as to maintain the current density on the anode of not more than 200 mA/cm². . Said Operation is performed using a membrane electrolyzer and a generator of direct current impulses. A titanium cathode having a coating of oxides of rhutenium, molybdenum, tungsten or another known metal is used as the cathode. The electrolysis process is performed by the direct current in the impulse mode that inhibits formation of a layer of oppositely charged ions that leads to reduction of the mass exchange between the electrode surface and the water being purified and to reduction of the electrolyzer operation efficiency. The Operation 9 is based on the processes e), h).

According to the Operation 10, ions of the substances dissolved in the water are separated on the ion-exchange membranes under influence of the electromagnetic field formed by the direct current. Said Operation is performed using an electrodialysis reactor and a generator of direct current impulses having a voltage of up to 150 V. The anode made of the material that is resistant to the electrochemical erosion and the cathode made of titanium coated with the layer of metal oxides are used. Separation of the ions and molecules of individual inorganic compounds is performed in the range of pH values of the water being purified of between 5.0 and 7.0; wherein selection of the pH level of the water being purified depends on the chemical formulation of the substances to be separated from the flow of the water being purified. The process is performed under the direct current voltage in the range of between 3 and 5 V per one pair of the ion-exchange membranes, wherein the direct current voltage is regulated automatically through the electric conductivity of the water being purified and the concentrate being formed so as to maintain the current density at the level of 1 - 5 mA/cm². The concentrate being formed is supplied to further purification: to the membrane electrolyzer or to processing by the cold plasma, or to the ultrafiltration membrane. Selection of the concentrate purification process depends on the chemical formulation of the contaminating agents in the concentrate. The Operation 10 is based on the process i).

According to the Operation 11, the ions and molecules of the compounds dissolved in the water are separated on the ultrafiltration membrane in a flow through mode. Filtration of the water being purified is performed under pressure of between 4 and 7 atmospheres. This results in formation of up to 30% of the concentrate from the volume of the water being purified that is supplied to filtration, wherein the concentrate is supplied to further purification in the electrodialysis apparatus or by the cold plasma, or either in the anode or in the cathode chamber of the membrane electrolyzer. Selection of the concentrate purification process depends on the chemical formulation of the contaminating agents in the concentrate. Purification of the ultrafiltration membrane from mineral layerings is performed by the water having a pH in the range of between 2.0 and 4.0 that is obtained in the anode chamber of the membrane electrolyzer. Purification of the ultrafiltration membrane from organic layerings is performed by the water having a pH in the range of between 10.0 and 11.0 that is obtained in the cathode chamber of the membrane electrolyzer. After purification of the surface of the membranes, the water is supplied to the start of the technological scheme of the contaminated water purification. The Operation 11 is based on the processes e), f), g), h), i).

According to the Operation 12, the ions and molecules of the compounds dissolved in the water are separated on the reverse osmosis membrane in a flow through mode. Filtration is performed under pressure of between 4 and 7 atmospheres. This results in formation of between 25% and 50% of the concentrate, wherein the concentrate volume depends on the qualitative and quantitative formulation of the contaminating agents in the water being purified. The concentrate is supplied to further purification in the electrodialysis apparatus or by the cold plasma, or either to the anode or to the cathode chamber of the membrane electrolyzer. Selection of the concentrate purification process depends on the chemical formulation of the contaminating agents in the concentrate. Purification of the reverse osmosis membrane from mineral layerings is performed by the water having a pH in the range of between 2.0 and 4.0; wherein the water having the pH in the range of between 2.0 and 4.0 that is obtained in the anode chamber of the membrane electrolyzer. Purification of the reverse osmosis membrane from organic layerings is performed by the water having a pH in the range of between 10.0 and 11.0, wherein the water having the pH in the range of between 10.0 and 11.0 that is obtained in the cathode chamber of the membrane electrolyzer. After purification of the surface of the membranes, the water is supplied to the start of the technological scheme of the contaminated water purification. The Operation 12 is based on the processes e), f), g), h), i).

Thus, generally the purification of the contaminated water is performed in the following fashion.

Firstly, values of parameters of the water being purified are determined by means of sensors of the detection unit. Then, the determined data is transmitted to the control unit. In fact, controllers of the control unit collect the data from the sensors. Based on the obtained data, by means of the control unit, namely, by means of its microprocessors, the water purification scenario is created that determines at least a portion of the Operations 0-12, their modes, and sequence, i.e., it selects the technological process of the contaminated water purification with these values of parameters in order to bring the values of parameters into compliance with the given requirements. The water is purified by means of the purification unit that is controlled by the control unit (by generating and transmitting control signals by the controllers of the control unit to executive devices of the purification unit) according to the created scenario, in other words, according to the selected technological process.

Essentially, the determined portion of the Operations 0-12 is combined into a single technological process by means of the control unit according to the created scenario. Such combination is performed automatically at the moment of supplying the contaminated water having certain values of parameters to the system by means of pipelines and valves. At the moment of supplying the contaminated water having a formulation that differs from the previous one to the system, the current created scenario is switched to a new one that is developed for purification of the contaminated water having changed values of parameters and, therefore, the current technological purification process is changed to a new one automatically in a real time. Such change occurs without changing a physical configuration of the system equipment. It is obvious that the system that implements the claimed method operates based on the corresponding software.

By means of the system that implements the described purification method, two or more technological processes according to the created scenario are performed simultaneously in parallel and independently, if necessary. And the equipment of the purification unit used in this case may be partially shared for certain Operations of both processes or completely different for all Operations of both processes.

During implementation of the selected technological purification process, data about values of parameters of the water being purified and already purified, e.g., values of pH, turbidity, electric conductivity etc., may be collected and accumulated in the database.

Hydrogen that precipitates on the electrodes may be collected followed by its use as a fuel for generating the electric energy for the technological process needs.

Variants of combining separate operations into a single technological process for purifying the contaminated water depend only on the detected values of parameters of the water being purified, while their overall number is affected only by the number of the operations which may be performed.

Examples of the purification scenarios for the contaminated water having various values of parameters are stated below. Said examples define specific Operations from the Operations 0-12, their modes, and a sequence in order to bring the values of the water parameters into compliance with the requirements of the drinkable water standard. Example 1. 100 1 of the filtrate of the solid domestic waste landfill having values of parameters “biological oxygen demand” BOD = 4500 mg0₂/l, “chemical oxygen demand” COD = 7350 mg0₂/l, pH = 8.3 were supplied for purification. The purification was performed according to the following scenario: Operation 0 + Operation 2 + Operation 3 + Operation 4 + Operation 11 + Operation 8 + Operation 9 + Operation 4. The Operations 8, 9, 4 are associated with purification of the concentrate having a volume of up to 50 1 until the drinkable water standard is achieved. At the output, 99 1 of the water having BOD = 2 and COD = 10 at the pH = 8.0 were obtained.

Example 2. 100 1 of waste water contaminated with fuel and greasing materials having a concentration of 150 mg/1 in terms of greases and 35 mg/1 in terms of a diesel fuel and pH = 7.4 were supplied for purification. The purification was performed according to the following scenario: Operation 0 + Operation 1 + Operation 5 + Operation 11 + Operation 8 + Operation 9 + Operation 4. The Operations 8, 9, 4 are associated with purification of the concentrate having a volume of up to 30 1 until the drinkable water standard is achieved. At the output, 99 1 of the water having the content of the greases and diesel fuel at the level of 0.01 mg/1 having the pH = 7.9 were obtained.

Example 3. 100 1 of the contaminated water having a content of pesticides of 1.0 mg/1 at the pH = 6.9 were supplied for purification. The purification was performed according to the following scenario: Operation 0 + Operation 12 + + Operation 8 + Operation 9 + Operation 4. The Operations 8, 9, 4 are associated with purification of the concentrate having a volume of up to 50 1 until the drinkable water standard is achieved. At the output, 99.5 1 of the water having the content of pesticides at the level of 0.001 mg/1 having the pH = 7.1 were obtained.

Example 4. 100 1 of the contaminated water having a content of ammonium of 45 mg/1 at the pH = 10.2 were supplied for purification. The purification was performed according to the following scenario: Operation 0 + Operation 10 + Operation 7 + Operation 5 + Operation 11. The Operations 7, 5, 11 are associated with purification of the concentrate having a volume of up to 50 1 until the drinkable water standard is achieved. At the output, 99.5 1 of the water having the total nitrogen content at the level of 0.001 mg/1 having the pH = 7.5 were obtained.

Example 5. 100 1 of the filtrate of the solid domestic waste landfill having the BOD = 4500 mg0₂/l, the COD = 7350 mg0₂/l at the pH = 8.3 were supplied for purification simultaneously with separate flows with 100 1 of the contaminated water having the content of pesticides of 1.0 mg/1 at the pH = 6.9. The purification of the filtrate of the solid domestic waste landfill was performed according to the following scenario: Operation 0 + Operation 2 + Operation 3 + Operation 4 + Operation 11 + Operation 8 + Operation 9 + Operation 4. The Operations 8, 9, 4 are associated with purification of the concentrate having a volume of up to 50 1 until the drinkable water standard is achieved.

The purification of the water contaminated with pesticides was performed according to the following scenario: Operation 0 + Operation 12 + Operation 8 + Operation 9 + Operation 4. The Operations 8, 9, 4 are associated with purification of the concentrate having a volume of up to 50 1 until the drinkable water standard is achieved. Two flows of the contaminated water at first Operations, namely, prior to the step of the concentrate purification, were purified simultaneously by performing various processes and on various equipment involved. Identical processes and equipment were used at the steps of purification of the concentrate of both flows which constitute 100 1 in total. At the output, up to 199 liters of the water were obtained, and the water was compliant with the drinkable water standard in terms of the content of the substances dissolved therein.

Therefore, the method for treating the contaminated water has been developed that enabled to achieve the technical effect that lies in enabling purification of contaminated waters having a qualitative and a quantitative formulation of contaminating agents that varies within a wide range until the compliance of values of parameters of said waters, i.e. of their quality, with given requirements with minimum energy, time costs and consumption of reagents.

Claims

1. A method for purifying a contaminated water by means of a system comprising a detection unit, a control unit, and a purification unit which are operatively connected between each other, the method comprises the following steps of: determining values of parameters of the water being purified by means of the detection unit, transmitting a data about the values of the parameters of the water being purified to the control unit, creating a water purification scenario that determines at least a portion of purification operations available for performing by the purification unit, their regimes and sequence, to achieve a compliance of the values of the water parameters with given requirements by means of the control unit based on the received data, purifying the water by means of the purification unit that is controlled by the control unit according to the created scenario, characterized in that as the purification unit, a set of equipment is used which is configured to perform purification operations which are based at least on processes of: a) destroying hydration shells of ions and/or molecules of the contaminating agents under influence of the energy of cavitation processes followed by transformation of the released ions and/or molecules into molecules of insoluble compounds at a pH higher than 9.0; b) destroying hydration shells of ions and/or molecules of the contaminating agents under influence of the energy of cavitation processes followed by formation of molecules of complex compounds from the released ions and/or molecules and sorption of the molecules of complex compounds by a preliminary added sorbing agent at a pH of between 5.0 and 9.0; c) destroying the hydration shells of the ions and/or molecules of organic and inorganic compounds of the contaminating agents under exposure of the energy of the hydrated electrons and hydrogen ions followed by reduction and/or cleavage, and/or dissociation of the released ions and/or molecules and formation of the complex compounds having surfactant properties at a pH of between 5.0 and 8.0 from the obtained ions and/or molecules; d) destroying the hydration shells of the ions and/or molecules of the contaminating agents under influence of the energy of the hydrated electrons, hydrogen ions, and water electrolysis products followed by reduction and/or cleavage, and/or dissociation of the released ions and/or molecules and sorption of the obtained particles by the contaminating agents in the form of preliminary coagulated organic substances at a pH of between 2.0 and 3.0; e) destroying hydration shells of ions and/or molecules of the contaminating agents under influence of the energy of the hydrated electrons followed by transformation of the released ions and/or molecules into molecules of complex insoluble compounds at a pH of between 9.0 and 11.0; f) destroying the hydration shells and the contaminating agents under influence of the energy of cavitation processes and/or energy of the hydrated electrons, and/or energy of the water electrolysis products followed by sorption of the released ions by the preliminary formed complex insoluble compounds; g) destroying the molecules of the organic compounds of the contaminating agents by a full oxidation thereof under influence of the energy of the hydrated electrons and water electrolysis products until a state of carbon dioxide at a pH of between 3.0 and 5.0; h) decontaminating the water being purified under influence of the hydrated electrons and water electrolysis products; i) separating the contaminating agents from the water being purified.

2. The method according to claim 1, characterized in that the purification processes which the purification operations are based on are performed simultaneously or successively.

3. The method according to claim 1 , characterized in that a set of sensors which include at least pH, turbidity, and electric conductivity sensors is used as the detection unit.

4. The method according to claim 1, characterized in that the determination of the values of the water parameters is performed continuously, while if the values of said parameters are changed as compared to their previous values, the water purification scenario will be changed in a real time.

5. The method according to claim 1, characterized in that the hydrated electrons and ions of hydrogen are generated on titanium electrodes under influence of the electromagnetic field having an alternating force and a voltage of between 5 and 2000 V and a direct current density in the range of between 5 and 300 mA/cm².