RU2650168C2 - Method and system for the treatment of produced water and fluids with chlorine dioxide for re-use - Google Patents

Abstract

FIELD: drilling soil or rock.

SUBSTANCE: invention relates to methods and systems for treating formation water associated with the drilling, pumping and extraction of gas and oil, or other industrial aqueous fluids. Method for reducing or eliminating from an aqueous fluid a pollution selected from the group consisting of calcium, magnesium, sodium, iron, chloride, manganese, calcium chlorate, sulfate, barium, hydrocarbons, total dissolved solids, biological contamination and combinations thereof comprises: introducing into the aqueous fluid an oxidant selected from the group consisting of oxygen, air, oxygen-enriched air, and combinations thereof, the introduction into the fluid of the first chlorine oxide selected from the group consisting of chlorine dioxide, chlorite and combinations thereof, and introducing a second chlorine oxide into the aqueous fluid after the introduction of the oxidant and the first chlorine oxide, the second chlorine oxide containing chlorine dioxide, chlorite or a combination thereof.

EFFECT: invention provides improved treatment of formation water, reduction or elimination of contaminants contained therein, as well as the possibility of re-use of treated water, in particular re-use as fluid for hydraulic fracturing.

24 cl, 9 dwg, 7 ex, 6 tbl

Description

FIELD OF THE INVENTION

[0001] This invention generally relates to methods and systems for treating formation water associated with drilling, pumping and producing gas and oil, including, but not limited to, a hydraulic fracturing method. In particular, the present invention relates to an improved method and system for treating produced water, return water, feed water or other industrial aqueous fluids in order to reduce pollution and bring treated water to standards so that the treated water can be reused for hydraulic the gap.

BACKGROUND

[0002] In oil and gas production, a huge amount of water is used as part of the whole process. The main interest is the large amount of water used to form cracks in oil or gas wells in order to increase production from a given formation. The water used in this process should not contain any contaminants that could adversely affect the efficiency of the hydraulic fracturing process. In particular, hydrocarbon-containing metals, inorganic contaminants or metal ions, phosphates, volatile organic compounds (VOC), total dissolved solids (TDS) and other contaminants can adversely affect the performance of the polymers used to reduce friction and / or to hold sand in suspension condition. In addition, the reduction or elimination of bacterial contamination, which can impair the performance of the polymer and / or contaminate the producing formation, is of great importance. For example, bacterial contamination of the formation can cause blockage or decrease in production and lead to the formation of hydrogen sulfide, which negatively affects the well’s performance and the value of the product. The present invention provides a process for treating formation water and for meeting standards, enabling reuse of treated formation water in a subsequent hydraulic fracturing process.

[0003] In the prior art, various methods and systems for treating formation water have been investigated and known. An example of such technologies is reverse osmosis, microfiltration, electrocoagulation, etc. These technologies have severe restrictions on the various contaminants that they may encounter during one step and require high operating costs at a relatively low processing speed. For example, although reverse osmosis (RO) is effective in eliminating ionic impurities, hydrocarbon contamination can seriously clog and / or damage the reverse osmosis (RO) membrane, so that on an industrial scale, the technology becomes unrealistic. Similarly, the presence of certain cations and anions can cause clogging, scale formation or other types of interference.

[0004] Wastewater associated with oil production, ie Commercial waters generally consist of two primary sources: return water and produced water. As a rule, due to the too high content of impurities and bacteria, the reuse of these waters is difficult. In particular, production water and fracturing water (or fractured water) can be contaminated, for example, by bacteria present in the formation with naturally occurring organic substances, organic processing chemicals (e.g., thickeners, emulsion stabilizers, etc.) and process chemicals (for example, agents that reduce the formation of precipitation, friction reducers, anti-corrosion chemicals, pH modifiers, etc.), and / or other contaminants, which leads to a high total percentage aniyu dissolved solids. The presence of these contaminants may interfere with subsequent reuse of water, storage and / or disposal (for example, injection into wells to discharge formation wastewater or disposal to municipal wastewater treatment plants).

[0005] Municipal wastewater treatment plants are dealing with increasingly stringent regulatory requirements for wastewater associated with hydraulic fracturing, and meeting these requirements is costly. Similarly, to the extent that contaminated fracturing water and production water is stored in fishing pits, open or slop basins, high residual polymer levels and solid loads in these pits can contribute to the generation of large amounts of hydrogen sulfide, causing environmental problems. and security.

[0006] Recently, manufacturers have switched to closed systems as a preferred method for treating return water and produced water (ie, reusing these waters in subsequent operations). The water itself used in hydraulic fracturing operations is often a combination of formation water and / or return water, surface water and / or municipal water (this water is also known as “mixed water”). Due to the successful treatment of contaminated produced water in intermediate sumps and storage tanks, mixed water may contain a higher percentage of produced water than usual, which, in turn, provides a reduction in disposal costs, fresh water costs and problems associated with the use of / repeated use of water. Low costs and simple technologies are necessary so that processing processes can be easily used by small producers or in individual production zones.

[0007] The process disclosed herein is a cheap, unexpectedly effective processing method that works well in difficult process conditions associated with produced water produced by gas and oil production, for example, having a high content of one or more of the following substances: calcium (Ca ), magnesium (Mg), barium (Ba), iron (ferrous iron Fe ²⁺ or ferric iron Fe ³⁺ ), manganese (Mn), as well as hydrocarbons, sulfates (SO4), total organic carbon (TOC), the total amount dissolved solid ve substances (TDS), volatile organic compounds (VOC) and bacterial contamination.

[0008] The methods and system disclosed herein can reduce and / or effectively eliminate bacterial contamination, hydrocarbon-containing metals, inorganic contaminants or metal ions, phosphates, VOC, TSS, TDS and other contaminants resulting from wastewater generated from oil production and gas, in order to ultimately reduce the total amount of water directly or indirectly used in oil production, as well as to ensure the possibility of reuse of treated formation water as a fracturing fluid . In particular, the new, highly effective treatment method and system disclosed herein are extremely and unexpectedly effective in treating highly contaminated formation water by removing and / or reducing certain inorganic contaminants, for example, Ca, Mg, Na, Fe, Cl, Mn, TDS, CaClO ₃ , SO ₄ , Ва, and also hydrocarbons, biological pollution and other colloids. In addition, as a result of adjusting the physical and chemical parameters of the process, some pollutants can be selectively set as targets with high removal rates.

[0009] The unique chemical and physical properties of chlorine dioxide make it ideal for use in fracturing fluids. As an oxidizing agent, it can penetrate into hydrocarbons and destroy emulsions, making it possible to separate and recover hydrocarbons, as well as reduce and / or eliminate biological pollution. Due to the specificity of chlorine dioxide, its oxidizing ability can be directed to such pollutants as sulfides and residual polymers without the formation of undesirable by-products. In addition, unlike bleach or chlorine, chlorine dioxide does not lead to the formation of chlorination by-products, which can cause problems associated with operation or the environment.

[0010] However, chlorine dioxide (and / or chlorite) is difficult to control, and care must be taken in its manufacture, handling, and storage. In addition, chlorine dioxide may be expensive depending on the consumption of chlorine dioxide in the treatment of wastewater and / or source water. In various embodiments of the invention, the oxidizing ability of chlorine dioxide is used together with oxygen (or air) to obtain unexpected results, unexpected increase in efficiency and unexpected productivity in the treatment of these waters, unattainable with the current level of technology.

[0011] Furthermore, according to some various embodiments of the invention, a combination of chlorine dioxide disinfection and oxidation is used to provide a fast wastewater treatment. Such methods and systems result in increased productivity of chlorine dioxide and in increased efficiency in relation to the volumes of treated water, which reduces the use of chemicals, energy and reduces the amount of wastewater, which in turn leads to a decrease in the load on the environment and cost reduction .

[0012] In accordance with one or more such embodiments of the invention, the use of chlorine dioxide in a closed system for treating reservoirs storing commercial wastewater or produced water has an unexpected potential to reduce bacterial contamination, Ca, Mg, Na, Fe, Cl, Mn , TDS, CaClO ₃ , SO ₄ , Ва, oil, grease, and their combinations, thus ensuring a reduction in the cost of processing, disposal of fluids and added water (by making it possible to use more commercial wastewater as fracturing fluid), as well as reducing environmental and safety issues. In alternative embodiments, chlorine dioxide can also be used for pretreatment and disinfection of fracturing fluids prior to use in oil production and / or fracturing operations, including, but not limited to, surface water, produced water, municipal water, return water, or any combination thereof.

[0013] Accordingly, it is necessary to create methods and systems for treating wastewater associated with the drilling, pumping and production of gas and oil (ie formation water) in order to eliminate the disadvantages associated with existing treatment methods. In particular, it is necessary to create methods and systems for improved treatment of produced water for reuse as fracturing fluids.

[0014] Although certain aspects of standard methods have been considered to facilitate the description of the present invention, the invention does not in any way dispense with these technical aspects, it is contemplated that the claimed invention may include one or more of the standard technical aspects discussed herein.

[0015] If in this description there is a reference to a document, act or object of knowledge or relevant consideration, then this reference or consideration does not constitute recognition that this document, act or object of knowledge or any combination thereof at the priority date was publicly available, well known, were part of well-known information, or otherwise form the level of technology under the relevant legislative provisions, or knowingly refer to an attempt to solve any of the problems considered in this description.

SUMMARY OF THE INVENTION

[0016] In one aspect, the invention relates to a method comprising the following steps.

[0017] Step 1. Formation fluids are transferred to a container providing a residence time of 30 to 60 minutes.

[0018] Step 2. The fluid is removed by pump from the first vessel, passed through a venturi, and returned to the first treatment vessel. Air is introduced into the venturi to provide finely divided and / or dispersed air flow back to the first reservoir. In addition, a sodium chlorite solution or a combination of sodium chlorite and sodium hydroxide, or both of these chemicals, as separate portions is introduced into the return pipe. Alternatively, other raw materials may be added to make it possible to provide the desired mixture. The feed stream is taken at about 20% of the bottom of the tank. The fluid is drained using a distribution line located on the midline of the tank. The first container has means for removing hydrocarbons or other material having a low specific gravity, as well as means for removing solid particles having a high density.

[0019] Step 3. Fluid is supplied from the first reservoir to the midline of the second reservoir. Chlorine dioxide gas is introduced through the transfer line. The dosage of chlorine dioxide is sufficient to obtain a residual content in the second container.

[0020] Step 4. The residence time in the second container is approximately 30 to 60 minutes. The second tank has a bottom drain to the third tank. The second tank has means for removing flocculant material having a low specific gravity.

[0021] Step 5. The residence time in the third vessel is from about 10 to 30 minutes. This tank has an overflow into a third tank or a clean tank. In addition, this container has means for removing solid particles having a high density from the bottom of the container.

[0022] The following terms used herein mean the following meaning.

[0023] Chlorine dioxide consumption or consumption is the amount of chlorine dioxide (or other oxidizing agent) consumed by background chemically active contaminants (both inorganic and organic materials) in a given sample of wastewater (ie field water), fracturing fluid processing fluids or other targeted fluids. The consumption of chlorine dioxide is determined by subtracting the amount of chlorine dioxide remaining after a certain time from the amount of chlorine dioxide initially added to the system.

[0024] Free residual content or residual content is the amount of chlorine dioxide (or other oxidizing agent) that is currently available for the reaction with biological substances after background contamination (or “consumption”) has been processed. In other words, the amount of chlorine dioxide (or other oxidizing agent) available for bacterial control.

[0025] A biocide is a reagent capable of killing living microorganisms, usually selectively (it is also called a bactericidal agent or antibacterial agent).

[0026] Biological contamination is any living microorganism or a byproduct of a living microorganism found in wastewater (ie, commercial waters), fracturing fluids, processing fluids, in source water or other target fluids.

[0027] Biologically effective amount is an amount that controls, kills or otherwise reduces the microbial content in wastewater (ie, production water), fracturing fluids, treatment fluids, source water, or other target fluids in question.

[0028] Well fluid or fracturing fluid is any fluid used in the drilling, completion, repair, and operation of underground oil and gas wells. Typically, it includes feed water (or untreated water, or groundwater, such as fracturing water) plus any additives.

[0029] Hydraulic fracturing water — feed water used in the hydraulic fracturing process from any source, in particular surface water, municipal water, treated return water, or treated formation water.

[0030] Formation water is water naturally occurring in an underground formation and extracted to the surface as part of a fracturing or oil recovery operation.

[0031] Backflow water is a recyclable fracturing fluid that flows back to the surface after being pumped into an underground formation as part of a fracturing or oil recovery operation.

[0032] Well water - in the context of the invention, this water includes produced water, backflow water and other fluids that are by-products of oil production, fracturing or other oil production processes.

[0033] Furthermore, in the context of the invention, the words “comprises,” “has,” and “includes,” as well as all relevant grammatical variations in each case, have an open, non-limiting meaning that does not exclude additional elements or parts of a node or structural element .

[0034] A person skilled in the art will readily appreciate the distinguishing features of this invention when reading the following description of its embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The invention is particularly shown and clearly defined in the claims following the description. The above and other features and advantages of the present invention can be understood from the following more detailed description of preferred embodiments with reference to the accompanying drawings, in which the following is shown.

[0036] FIG. 1 is a schematic view of a typical water treatment system in accordance with an exemplary embodiment of the invention.

[0037] FIG. 2. is a schematic view of another embodiment of the invention.

[0038] FIG. 3. is a schematic view of another embodiment of the invention.

[0039] FIG. 4. is a schematic view of another embodiment of the invention.

[0040] FIG. 5. is a schematic view of another embodiment of the invention.

[0041] FIG. 6. is a schematic view of another embodiment of the invention.

[0042] FIG. 7. is a schematic view of another embodiment of the invention.

[0043] FIG. 8. is a schematic view of another embodiment of the invention.

[0044] FIG. 9 illustrates one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0045] To facilitate an understanding of the principles of the present invention, references are made to its embodiments depicted in the drawings, and specific language is used in its description. Obviously, this does not mean any limitation on the scope of the invention, it being understood that one skilled in the art to which the invention relates can make any changes and further modifications to the described embodiments of the invention, as well as any additional applications of the principles described herein.

[0046] The terminology used here is only to describe individual embodiments of the invention and is not intended to limit it. The singular forms used also include the inclusion of the plural forms, unless the context expressly expresses the opposite. In addition, it is clear that the expressions “enclose” (and any of its forms, for example, “encloses” and “enclosing”), “have” (and any forms of it, for example, “has” and “having ")," include "(and any form thereof, for example," includes "and" including ", and" contain "(and any form thereof, for example," contains "and" comprising ") are free verbs-connectives. Therefore, a method or device that "comprises", "has", "includes" or "contains" one or more steps or elements, contains one or more of these stages or elements, but not limited to the content of only this one or these several stages or elements.Likewise, a method step or element of a device that "comprises", "has", "includes" or "contains" one or more distinctive features possess one or more of these distinctive features, but are not limited to possessing only this one or these several distinctive features. In addition, a device or structure configured in a certain way is configured at least in this way, but it can be configured in a way that is not listed.

[0047] Hydraulic fracturing and other processes associated with drilling in oil fields and with oil production require large amounts of water and, in turn, create large amounts of wastewater. In addition, many other types of industrial exploitation are based on the use of large quantities of water and lead to the formation of large quantities of wastewater, all of which require treatment. These industries, in particular, include agriculture, the chemical, pharmaceutical, mining, metal plating, textile, brewing, food processing, beverage and semiconductor industries. The presence of biological pollution and other organic pollutants leads to a decrease in efficiency and can cause damage (i.e. corrosion, clogging, growth of harmful bacteria). Similarly, waters having a high level of residual organic or biological pollution are not suitable for use in oilfield operations and need to be treated before they are pumped underground and injected into the underground formation.

[0048] In accordance with embodiments of the present invention, chlorine dioxide can be used to treat produced water (including produced water, return water, and surface water) to both reduce the biological load and promote decomposition of residual organic pollution in the water. For example, but without limitation, one or more embodiments of the invention can be used to treat produced or return water before it is diverted or reused. Both produced water and backflow water tend to have a significant content of organic pollutants (e.g., hydrocarbons, oil, oil and grease, organic matter associated with diesel fuel, benzene, toluene, ethylene, xylene), polymers ( for example, polyacrylamides), iron (Fe), VOC, inorganic transition metals or metal ions, suspended solids and other contaminants.

[0049] In an exemplary embodiment of the invention, the proposed method can be used in a closed-loop continuous system for treating produced or return water before reusing this water in a subsequent hydraulic fracturing operation. However, and still in accordance with the invention, these methods can also be used as pretreatment of water for fracturing, in particular for pretreatment on the fly before placing water in intermediate sumps, tanks or sump pools, or as parts of a large number of other various systems in oil fields.

[0050] For example, one embodiment is a formation water treatment process that significantly reduces bacterial contamination, hydrocarbon-containing metals, inorganic contaminants or metal ions, phosphates, VOC, TDS, and other contaminants in wastewater arising from the extraction of oil and gas, compared to conventional processing methods. Thanks to this process, the final chlorine dioxide content in the treated formation water can be from about 0.1 to 50 mg / l; as a result, the treated formation water can be reused, for example, as a fracturing fluid, without the need for additional processing technologies (e.g. reverse osmosis systems). In particular, the proposed system and method led to an unexpected and unattainable on an industrial scale reduction in the content of metal ions, including iron, calcium, manganese, magnesium and barium.

[0051] In some embodiments, the amount of chlorine dioxide needed to treat the produced water is significantly less than what would be expected by a person skilled in the art and significantly less than what would be required if chlorine dioxide was used separately, which also provides significant financial and economic benefits for industrial applications on a large scale.

[0052] FIG. 1 shows one embodiment of a closed wastewater treatment system 150 in accordance with some embodiments of the invention. During operation, and as shown by way of example in FIG. 1, untreated reservoir fluid 2 is pumped or delivered through a treatment system inlet 17 to a first treatment tank 101 through a pump 18. In particular, but not limited to, as shown in FIG. 1, the first processing tank 101 is a fracturing tank installed at an oil and gas production location. Before being supplied to the first container 101, the fluid 2 can be stored in one or more fracturing storage tanks 500 (as shown in FIG. 1). In alternative embodiments, the fluid 2 can be supplied to the first container 101, for example, directly from a truck, from a pump, pit or well using various delivery methods and devices known in the art.

[0053] In exemplary embodiments, although not required, the untreated reservoir fluid 2 is a stream of highly contaminated wastewater from oil and gas production and having a high content of contaminants selected from the group consisting of bacterial contamination, Ca, Mg, Na, Fe, Cl, Mn, TDS, CaClO ₃ , SO ₄ , Ва, oil, lubricant, and combinations thereof. In some embodiments, prior to being supplied to the first treatment tank 101, the fluid 2 is subjected to methods known in the art for initial hydrocarbon separation. Before entering reservoir 101, fluid 2 (for example, untreated untreated formation water) has a first initial consumption of 200, which can be determined using measurement methods known in the art.

[0054] In the context of this description and with reference to FIG. 1, treated wastewater, for example, produced water contained in the tank 101, is called "fluid 2A". The first processing tank 101 provides a residence time of fluid 2a of about 15 to 60 minutes. The total residence time required for the fluid 2a may vary and depend on the properties of the fluid and other environmental factors. For example, in some embodiments, the residence time is 15, 18, 20, 22, 25, 27, 30, 35, 40, 45, 50, 55, or 60 minutes, including any and all relevant ranges and subranges (e.g., 15 to 60 minutes, from 18 to 55 minutes, from 15 to 30 minutes, from 20 to 30 minutes, from 15 to 20 minutes, from 20 to 25 minutes, from 18 to 25 minutes, from 25 to 50 minutes, etc.)

[0055] As soon as the fluid 2a is supplied to the tank 101, it is removed from the first tank 101 by means of a circulation pump 3, passed through a venturi 4, and then returned to the first processing tank 101. The fluid feed stream 2a is withdrawn at a level of about 20% from the bottom of the first processing vessel 101, all through the transfer or distribution pipe 5. When the fluid 2a passes through the venturi 4, an oxidizer 40 is introduced into the venturi 4, which in this shown embodiment represents air to provide a finely divided or dispersed air stream in the return fluid 2a when it returns to the first container 101. Air (or oxidizing agent 40) is introduced at such a rate that s to prevent removal by aeration, so that removal of the volatile reducing agent (i.e. hydrogen sulfide) occurs rather than as a result of physical handling or physical removal, as by oxidation. By selecting an air flow rate that prevents or prevents the release of hydrogen sulfide or other volatile components present in the fluid 2a as a gas, these reducing agents are not likely to be cleaned, but oxidized in place by allowing the oxidizing agent to contact sulfides and the possibility of oxidation. In the embodiment shown in FIG. 1, oxidizing agent 40 is air. However, in alternative embodiments, oxidizing agent 40 may be oxygen, oxygen enriched air, or any chemical oxygen source or combination stable with chlorite. If, although this is not preferable, ozone is used, then at the first stage it should not be used in combination with chlorine dioxide, since ozone consumes chlorine dioxide. In addition, in alternative embodiments, the oxidizing agent 40 can be introduced into the fluid 2a not by means of a venturi 4, but by other means, for example, a spray rod, a pressurized source, an aerator, mechanical stirring, an air distributor, a diffuser, a spray or other air spraying agents known in the art.

[0056] The amount of the required dosage of the oxidizing agent 40 depends on the properties of the fluid 2 (for example, on the initial consumption 200), the processing system and the intended use or application, as well as other properties known to those skilled in the art. In exemplary embodiments, oxidizing agent 40 is added to the total volume of fluid to be treated 2a at an appropriate dosage and for an appropriate time to obtain a total dosage in the range of about 20 mg / kg to 2000 mg / kg of oxidizing agent 40, with a dosage of about 20 being preferred up to 1000 mg / kg of oxidizing agent 40 for the entire volume of the processed fluid 2a.

[0057] For example, in some embodiments, the dosage includes 20, 30, 50, 100, 250, 300, 500, 750, 800, 900, 1000, 1250, 1500, 1800, 2000 mg / kg of oxidizing agent for the entire volume of the treated fluid, including any and all relevant ranges and sub-ranges (e.g., from 20 to 2000 mg / kg, from 100 to 2000 mg / kg, from 300 to 2000 mg / kg, from 500 to 2000 mg / kg, from 1000 to 2000 mg / kg, from 20 to 1000 mg / kg, from 50 to 1000 mg / kg, from 100 to 1000 mg / kg, from 500 to 1000 mg / kg, from 20 to 500 mg / kg, etc.).

[0058] When the fluid 2a is removed from the first tank 101 by means of a circulation pump 3 and passed through a venturi 4 before it returns to the first treatment tank 101, either simultaneously with oxidizing agent 40, or substantially simultaneously with sodium chlorite solution (chlorite 30b). Alternatively, a combination of sodium chlorite (chlorite 30b) and sodium hydroxide (caustic soda 90) as a single portion is administered simultaneously with air or essentially simultaneously with air, or alternatively sodium chlorite (chlorite 30b) and sodium hydroxide (caustic soda 90) as two individual servings (not shown in the drawing). In a preferred embodiment, a 25% sodium chlorite solution supplied by DiKlor® by Saber Oxidation Technologies, Inc is used as chlorite 30b. However, other sources of chlorite 30b are available and known to the skilled person. In exemplary embodiments, chlorite 30b is added at the appropriate dosage and over the appropriate time to obtain a dosage in the range of treated fluid 2a ranging from about 10 mg / kg to 500 mg / kg. For example, in some embodiments, the dosage of chlorite 30b includes 10, 20, 23, 27, 30, 50, 100, 120, 180, 230, 250, 300, 420, 500 mg / kg, including any and all appropriate ranges and subranges (e.g., from 10 to 500 mg / kg, from 25 to 500 mg / kg, from 25 to 300 mg / kg, from 10 to 300 mg / kg, from 10 to 100 mg / kg, from 25 to 200 mg / kg, from 50 to 500 mg / kg, from 50 to 420 mg / kg, from 23 to 420 mg / kg, from 27 to 420 mg / kg, from 23 to 300 mg / kg, from 27 to 300 mg / kg, from 23 to 230 mg / kg, etc.).

[0059] In accordance with FIG. 1 after dosing with a combination of air, sodium chlorite and caustic soda (optional), the return fluid 2a is fed back to the container 101 through a distribution pipe 5 and / or other distribution means known in the art and designed to evenly distribute the fluid 2a in the first container 101. In this particular embodiment, the return fluid 2a is fed back to the container 101 along an axial or midline 8a (at half the vertical height of the fluid volume containing in the container), or essentially along the middle line of the first container 101. In order to distribute the fluid 2a during this step, a number of different means can be used, including, but not limited to, an immersion rod 19 (stationary or movable) with outlet openings fluid 2a as shown in FIG. 1, or a mechanism of a similar type, designed to be sprayed or evenly distributed and known in the art for wastewater treatment.

[0060] Due to the continuous circulation or recirculation of the fluid 2a from the tank 101, through the venturi 4 and then through the distribution pipe 5 back to the tank 101, the fluid 2a can sufficiently diffuse with the oxidizing agent 40 and chlorite 30b. Ultimately, this ensures that the fluid 2a in the first treatment tank 101 can be completely saturated and exposed to an oxidizing agent 40 and chlorite 30b that are substantially uniformly distributed throughout the tank 101. It should be noted that it unexpectedly turned out that the result of this first stage or phase which combine oxidizing agent 40 and chlorite 30b (and optionally caustic soda), there is a strong reduction in initial consumption of 200 or a high percentage of reduction in pollution compared with oxidation or aeration. x only with air / oxygen. For example, during phase 1 of the described process, the reduction in the initial consumption 200 in the processing tank 101 may practically be 70-80%. In some embodiments, and as shown in FIG. 1, the treatment system 150 can be set up so that during phase 1, chlorine dioxide (30a) can be introduced into the fluid 2a instead of or in combination with chlorite 30b.

[0061] In one or more embodiments, the first processing vessel 101 has floating removal means 6 for removing hydrocarbons or other material having a low specific gravity and floating to the surface of the fluid 2a. Removal means 6 are well known in the art of wastewater treatment. These include skimmers (e.g., blade type), conveyor belts, pneumatic flotation, or other equipment known in the art for removing lighter solids, hydrocarbons, or flocculants from the surface of a reactor. In some embodiments, the amount of hydrocarbons removed in this phase may be about 1-2% of the fluid 2a.

[0062] In one or more embodiments, the first processing vessel 101 also has a separation system 7 (or removal means) for removing high-specific precipitated or deposited solid particles from the bottom of the processing vessel 101. The separation system or removal means 7 comprise mechanical equipment known in the art for wastewater treatment, which can remove deposited solids from the bottom of the reactor and may comprise, for example, a screw or scraper mechanism. In an exemplary embodiment, a screw or scraper mechanism mounted on the bottom of the tank 101 rakes the deposited solid particles to the center of the tank where there is a recess, then the solids are pumped through this recess from the tank 101.

[0063] In a second phase of embodiments of the invention, and as shown in FIG. 1, treated fluid 2a is removed from the first processing tank 101 to an axial line 8b of the second processing tank 102 via a pump 27 and a transfer pipe 9. Chlorine dioxide gas is introduced into the fluid 2a in the region of the injector orifice 29 via a transfer pipe 9, before being distributed to the second container 102 as the fluid 2b. The dose of chlorine dioxide introduced into the fluid 2a is sufficient to obtain a residual chlorine dioxide content in the fluid 2b in the second treatment tank 102 and depends on the amount of biological contamination in the fluid. In some embodiments, the dosage of chlorine dioxide 30 is from about 10 to about 500 mg / L, for example, 10, 20, 25, 47, 50, 100, 120, 150, 210, 230, 250, 300, 335, 350, 400 500 mg / L, including any and all appropriate ranges and sub-ranges (e.g., from 10 to 500 ml / L, from 10 to 335 ml / L, from 25 to 500 ml / L, from 25 to 335 ml / L, from 25 to 230 ml / l, 45 to 335 ml / l, 45 to 500 ml / l, 47 to 335 ml / l, 50 to 400 ml / l, 20 to 230 ml / l, 20 to 47 ml / l, from 10 to 50 ml / l, etc.).

[0064] In some embodiments, the amount of biological contamination can be determined or monitored before introducing the crude fluid 2 into the treatment tank 101, immediately after removing the fluid 2a from the treatment tank 101, or in both of these cases. For example, from fracturing storage tanks 500, inlet 17, vessel 101, distribution pipe 5, or some combination thereof, one or more samples can be taken and tested for bacterial contamination. In alternative embodiments, flow control equipment may be coupled to enable continuous monitoring of biological contamination at several points along the treatment system. Testing can be carried out by means of a sample known to specialists in this field of technology and designed to determine the biological need and / or destruction of microbes.

[0065] The target residual concentration of chlorine dioxide in the treated water 2b depends on the expected duration of storage before reuse, for example, as a working fluid. For example, in the case of direct use as hydraulic fracturing water in a hydraulic fracturing system, the required residual chlorine dioxide content in the fluid 2b is from about 0.1 to 20 ml / L, preferably from about 0.5 to 5 ml / L. On the other hand, if the fluid 2b is intended to be stored for several days or longer, the target residual concentration of chlorine dioxide before reusing the fluid 2b as the working fluid should be from about 5 to 50 ml / l, preferably from about 20 to 50 ml / l One of skill in the art can calculate and determine the desired target residual content and, therefore, the required dosage, depending on the properties of the fluid 2b, the expected storage duration, intended use and other factors.

[0066] For example, in some embodiments, the target residual content includes 0.1 mg / L, 0.2 mg / L, 0.3 mg / L, 0.5 mg / L, 1.0 mg / L, 1.5 mg / L, 3 mg / L, 5 mg / L, 10 mg / L, 15 mg / L, 20 mg / L, 25 mg / L, 40 mg / L or 50 mg / L, including any all relevant ranges and subranges (e.g., from 0.1 to 50 mg / L, from 0.1 to 20 mg / L, from 0.1 to 10 mg / L, from 0.1 to 5 mg / L, from 0 , 1 to 2 mg / L, 0.5 to 20 mg / L, 0.5 to 10 mg / L, 0.5 to 5 mg / L, 1.0 to 20 mg / L, 1 , 0 to 10 mg / L, from 5 to 10 mg / L, from 5 to 40 mg / L, from 5 to 50 mg / L, from 10 to 50 mg / L, from 20 to 50 mg / L, etc. d.).

[0067] In order to prepare chlorine dioxide suitable for use in this invention, any suitable chlorine dioxide preparation method known in the art can be used. In general, chlorine dioxide solutions can be prepared by treating chlorite saline solutions (e.g. NaClO ₂ ) with an acidic solution to prepare acidic solutions containing ClO ₂ , which can then be introduced as gas into water to prepare an aqueous ClO solution ₂ . Other precursors, for example sodium chlorate, may also be used. For example, in a preferred embodiment, the invention provides a process involving the manufacture of chlorine dioxide by using, for example, a device such as a chlorine dioxide generator, for example, as described and claimed in US Pat. No. 6,468,479, the disclosure of which is incorporated herein by reference. Chlorine dioxide is generated either directly in the form of gas, or preferably in the form of a mixture of chlorine dioxide with water (or other suitable carrier fluid). Preferably, this generator operates with excess sodium chlorite to reduce the likelihood of generating chlorine gas as an impurity.

[0068] In accordance with FIG. 1, chlorine dioxide generator 75 is located in-line with a treatment system, while chlorine dioxide precursors (hydrochloric acid, sodium chlorite and sodium hypochlorite) are stored in tanks 76, 77 and 78, respectively. Venturi tube 28 has a stream of water flowing through it, through which a vacuum is created that draws chlorine dioxide from the reaction column of the generator into the water stream to form aqueous chlorine dioxide.

[0069] In an exemplary embodiment, the residence time of the fluid 2b in the second processing vessel 102 is from about 10 to 30 minutes, although the reaction time may vary depending on the properties of the fluid 2b. For example, in some embodiments, the residence time is 10, 13, 15, 18, 20, 22, 25, 27, or 30 minutes, including any and all relevant ranges and sub-ranges (e.g., from 10 to 30 minutes, from 12 to 30 minutes , from 15 to 30 minutes, from 20 to 30 minutes, from 10 to 20 minutes, from 10 to 25 minutes, from 15 to 25 minutes, etc.). The second tank 102 has a bottom discharge means 13 in a third processing tank 103. The bottom discharge means 13 may comprise a channel, pipe, pumping line, or any other means by which fluid 2b at the bottom of the vessel 102 can flow into the vessel 103 and which is well known in the art for wastewater treatment systems. In an exemplary embodiment, the second container 102 also comprises stripping means 14 (not shown) for removing lightweight flocculant material or other materials having a low specific gravity from the surface or top of the second processing tank 102. Examples of stripping means 14 used in the invention are well known in the art of wastewater treatment. These may include skimmers (e.g., blade type), conveyor belt, pneumatic flotation, or other equipment known in the art for removing lighter solids, hydrocarbons, or flocculants from the surface of the reactor.

[0070] The third processing vessel 103 comprises a fluid 2c. The residence time in the container 103 is approximately 10 to 30 minutes, although the reaction time may vary depending on the properties of the fluid 2c. For example, in some embodiments, the residence time is 10, 13, 15, 18, 20, 22, 25, 27, or 30 minutes, including any and all relevant ranges and sub-ranges (e.g., from 10 to 30 minutes, from 12 to 30 minutes , from 15 to 30 minutes, from 20 to 30 minutes, from 10 to 20 minutes, from 10 to 25 minutes, from 15 to 25 minutes, etc.).

[0071] The third container 103 has upper discharge means 15 (not shown) in the fourth container 104 or a clean tank. The overflow means 15 used in the present invention are well known and, for example, may comprise a channel, pipe, pumping pipe, or any other means by which the 2 s fluid present in the upper part of the container 103 can flow into the container 104, and which is well known in the field of technology related to wastewater treatment systems. The third tank 103 also has means for removing high density solids from the fluid 2d at the bottom of the tank 103, examples of which are well known in the art and which, for example, may include scrapers or screws located at the bottom of the tank.

[0072] In the embodiment shown in FIG. 1, treatment tanks 101-104 are fracturing tanks located at an oil and gas production site, and the disclosed formation water treatment system according to the invention is integrated into a closed system already existing at that location. In alternative embodiments, the method and system described above can be modified, however, they will still be within the scope of the invention disclosed herein and correspond to it. For example, in a more general case, in the alternative embodiments shown by way of example in FIG. 2, a closed processing system 150 according to the claims of the present invention is shown. In FIG. 2, a closed processing system 150 comprises a venturi 20, a flow of 100 fluid to be treated (e.g., sewage 15), a container or treatment / storage system 50, chlorine oxide 30, and oxidizing agent 40.

[0073] The fluid stream 100 contains wastewater 15, for example, a fluid stream from wastewater coming from an oil or gas field. For example, in FIG. 1, sewage 15 is untreated produced water 2. A combination of chlorine oxide 30 and an oxidizing agent 40 are introduced into stream 100. Chlorine oxide 30 preferably includes chlorite 30b, but it may also contain chlorine dioxide 30a or a combination of chlorite 30b and chlorine dioxide 30a, which are introduced into stream 100. For example, as discussed in connection with FIG. 1, sodium chlorite (i.e., chlorite 30b) can be introduced by venting using a venturi 20 (or venturi 4, as shown in FIG. 1), the venturi 20 being part of the fluid stream 100 being processed, or using other agents well known in the art. In alternative embodiments, a person skilled in the art may apply technology known in the art for introducing, mixing and / or diffusing chemicals in a processing system, either directly into a tank or into a fluid pipe, including but not limited to injection pumps, high pressure injectors, pumps, sewers, ducts, mixers, sprinklers, or a combination thereof.

[0074] In embodiments of the invention, the oxidizing agent 40 may be air, oxygen, oxygen enriched air, or any chemical oxygen source or a combination stable with chlorine dioxide (30a) and / or chlorite (30b), or some combination of these substances. In addition, in one or more embodiments, the oxidizing agent 40 is introduced by direct injection into the wastewater in the form of small bubbles (i.e., by means of air sparging, a pressurized source, aerator, mechanical stirring, diffuser, spraying or outlet through a tube 20 (4, 28) Venturi (see, for example, Fig. 1-9). If ozone 40 is used as an oxidizing agent, then at the first stage it should not be used in combination with chlorine dioxide, since ozone consumes chlorine dioxide. rather should change in the second phase or the second phase and only after the residual ozone concentration in the waste water or in an aqueous volume is exhausted or nearly exhausted.

[0075] In accordance with embodiments of the invention in the oil fields and for the purpose of hydraulically fracturing the formation, the storage or processing tank 50 (or system 50) contains wastewater 15 coming from source 10. Source 10 contains a source of produced water. In alternative embodiments, source 10 comprises return water, ground water, municipal water, fracturing water, wastewater, or any combination thereof. One of ordinary skill in the art will also understand that wastewater 15 can be any water or target aqueous fluid that is contaminated (e.g., with organic substances and / or microorganisms) and that is recycled or treated for reuse, storage and / or discharge back into the environment regardless of industry. In one or more embodiments, prior to treatment, the consumption of an oxidizing agent of pollutants in waste water 15 is from about 30 to 5000 mg / L, preferably from about 50 to 500 mg / L. This oxidizing agent consumption includes reducing agents including, but not limited to, reduced sulfur compounds, biomass and other biological by-products, and reduced metals, including but not limited to iron (Fe) II.

[0076] For example, in some embodiments, the oxidizing agent is 30, 50, 100, 250, 300, 500, 750, 800, 900, 1000, 1250, 1500, 2000, 3000, 4000 and 5000 mg / L, including any and all relevant ranges and subranges (e.g., from 30 to 5000 mg / L, from 100 to 2000 mg / L, from 300 to 2000 mg / L, from 500 to 2000 mg / L, from 1000 to 2000 mg / L, from 30 up to 1000 mg / l, from 50 to 1000 mg / l, from 100 to 1000 mg / l, from 500 to 5000 mg / l, from 50 to 500 mg / l, etc.).

[0077] In some embodiments, the venturi 20 is used to both generate and inject chlorine oxide 30 (eg, chlorine dioxide (30a)) and / or a combination of chlorine dioxide (30a) and chlorite (30b) into the fluid stream 100 and, in addition, for subsequent input of oxidizing agent 40. In other embodiments, separate venturi tubes are used (for example, in FIG. 1, venturi tubes 4 and 28). In a preferred embodiment, the carrier fluid 33 for the venturi 20 comes directly from the storage vessel 50. The tank 50 contains waste water 15, i.e. treated wastewater, or a combination of treated wastewater (or other target fluid) and treated wastewater. One skilled in the art will understand that, despite this, the carrier fluid 33 may come from any available water source located inline with the system 150.

[0078] As shown in FIG. 2-8, the storage and processing system 50 comprises one tank or tank. Despite this, in accordance with the invention, the tank system 50 contains several tanks, pits or ponds, or any other means of storage (for example, a tank, container or sludge pool) in which waste water 15 obtained from source 10. Tank system 50 may include one or more tanks, containers, containers, or other wastewater treatment systems suitable for treating wastewater 15. For example, as described in connection with FIG. 1, in fact, the tank 50 includes four processing tanks 101-104 and four storage tanks 500.

[0079] In embodiments of the present invention, chlorine oxide 30 and oxidizing agent 40 are supplied at such a rate that the removal of volatile reducing agents (ie, hydrogen sulfide) occurs rather than by physical treatment or physical removal, but by oxidation. Choosing an air flow rate that prevents the release of hydrogen sulfide (or other volatile reducing agents) present in wastewater 15 as a gas, these reducing agents are most likely not cleaned, but oxidized in place. The goal is to add oxidizing agent 40 to the fluid at a rate such that the fluid comes into contact with sulfides to allow oxidation. Thus, a flow rate that results in the addition of a strong air stream that removes sulfides before they can be oxidized should be avoided. The volume of fluid processed in the 50 tank system directly affects the flow range that can be used to avoid gas evolution and purification. Thus, the corresponding range is wide. For example, a small tank requires much less air consumption than a deep pond. However, one skilled in the art will be able to determine a flow rate suitable to prevent the treatment or removal of volatile reducing agents, depending on the volume, depth, and / or size of the tank system 50 (or the fluid being processed), the treatment system as a whole, and the oxidizer consumption.

[0080] FIG. 3, a diffuser 70 is used to introduce oxidizing agent 40. In one or more embodiments, as shown in FIG. 4, the oxidizing agent 40 is added directly to the wastewater 15 near the bottom of the vessel 50 using a pressurized source 80, and mechanical action can be used to enhance mixing of the wastewater 15 in the vessel 50. If a single point input method is used, it is preferable that the injector can move in the horizontal plane of the container 50 (this is not shown in the drawing).

[0081] In one or more embodiments of the present invention, chlorine oxide 30 and oxidizing agent 40 are introduced into waste water 15 as follows. First, chlorine oxide 30 is introduced for a sufficient time and in a dose sufficient to reduce the consumption of chlorine dioxide in wastewater treatment 15 in the range of about 10 to 20 percent, including all relevant ranges and sub-ranges (e.g. 12, 15 percent, etc. .). The required time and dosage depend on the properties of the wastewater 15 (for example, on the consumption of chlorine dioxide), the treatment system and the intended use. In one or more embodiments, during the initial (or first) processing step, chlorine oxide 30 contains only chlorite 30b. In those embodiments in which the chlorine oxide 30 contains only chlorite 30b, the step of introducing the oxidizing agent 40 can be performed (and in many cases this is preferred) immediately thereafter, synchronously, substantially synchronously or essentially simultaneously (see, for example, FIG. 1, a description of Fig. 1 and the examples provided herein). In exemplary embodiments, chlorite 30b is added at the appropriate dosage and over the appropriate time to obtain a dosage in the fluid 2a in the range of about 10 to 500 mg / kg. For example, in some embodiments, the dosage of chlorite 30b is 10, 20, 23, 27, 30, 50, 100, 120, 180, 230, 250, 300, 420, 500 mg / kg, including any and all relevant ranges and sub-ranges ( for example, from 10 to 500 mg / kg, from 25 to 500 mg / kg, from 25 to 300 mg / kg, from 10 to 300 mg / kg, from 10 to 100 mg / kg, from 25 to 200 mg / kg, 50 to 500 mg / kg, 50 to 420 mg / kg, 23 to 420 mg / kg, 27 to 420 mg / kg, 23 to 300 mg / kg, 27 to 300 mg / kg, 23 up to 230 mg / kg, etc.).

[0082] In alternative embodiments, the chlorine oxide 30 may be chlorine dioxide 30a, chlorite 30b, or a combination thereof. Since chlorine dioxide reacts as a free radical and, therefore, almost instantly, chlorine dioxide cannot be added at a high flow rate or in high concentration simultaneously with the addition of a large volume of oxidizing agent 40. Therefore, if during the first stage chlorine oxide 30 contains chlorine dioxide 30a (or combination of chlorite 30b and chlorine dioxide 30a), it is not possible to add oxidizer 40 at the same time until all chlorine dioxide 30a has been converted to chlorite 30b or, if this is done simultaneously, oxidant 40 must be added at a rate low enough to ensure that chlorine dioxide will not be removed or treated from wastewater 15 before it is dispersed through the fluid.

[0083] In addition, in some embodiments, either caustic soda (90) (not shown) can be added prior to treatment with chlorine dioxide 30 or simultaneously with this treatment to increase the pH of wastewater 15 to approximately 7 to 10. For example, in the embodiment described in connection with FIG. 1, sodium hydroxide (caustic soda 90) is added to obtain a pH value of approximately 8.5. Due to the use of a higher pH value for wastewater 15, polluting metals (for example, iron (Fe)) precipitate out of solution, while the formation of certain metal complex compounds that tend to form low pH is prevented. In other embodiments contemplated within the scope of the invention, the first step of adding chlorine oxide 30 may be skipped, depending on the consumption of chlorine dioxide, application, or existing system.

[0084] The oxidizing agent 40 is introduced into the wastewater 15 either before treatment with chlorine oxide 30, or in parallel with this treatment. Oxidizing agent 40 is added at the appropriate dosage and over the appropriate time to obtain a total dosage of approximately 20 to 2000 mg / kg of oxidizing agent 40 over the entire volume of wastewater treated 15, including all relevant ranges and subranges, with a dosage of approximately 20 being preferred up to 1000 mg / kg of oxidizing agent 40 for the entire volume of the processed fluid. The required time and dosage again depends on the properties of the wastewater 15 (for example, on the consumption of chlorine dioxide), the treatment system and the intended use, along with other considerations regarding mechanical equipment that are known to those skilled in the art. In one or more embodiments, as a result of using oxidizing agent 40, a total of about 10 to 90 percent of the total consumption of chlorine dioxide is consumed, preferably about 60 to 90 percent of the consumption of chlorine dioxide. For example, in some embodiments, the oxidizing agent will require a flow rate of 10, 20, 25, 40, 50, 60, 65, 70, 80, or 90 percent of the consumption of chlorine dioxide, including any and all relevant ranges and sub-ranges (e.g., 10 to 25 , from 10 to 70, from 15 to 90, from 20 to 80, from 50 to 85, from 60 to 80, from 60 to 90 percent, etc.).

[0085] The step of introducing oxidizing agent 40 during the first processing step can be performed substantially simultaneously, synchronously or immediately after the first step of adding chlorine oxide 30, in particular if chlorine oxide 30 is only chlorite (30b). As described above, the synergistic effect of the oxidizing agent and chlorine oxide can reduce the initial intake by about 70-80% or more.

[0086] In the next step (or the second processing step), chlorine oxide 30 is introduced in an amount sufficient to obtain the target residual ClO ₂ content in the fluid, which depends on the consumption of the oxidizing agent in the fluid. For example, in the case of FIG. 1, after sodium chlorite, air and caustic soda are introduced into processing tank 101 in a processing step 1 during a certain period of time (i.e., from about 15 to 60 minutes), in a second step, chlorine dioxide is introduced into a second tank 102 processing until you get the target residual content of chlorine dioxide. Despite this, in alternative embodiments, during this second step, chlorine oxide 30 may contain chlorine dioxide 30a, chlorite 30b, or a combination thereof. It may be, but not necessarily, chlorine oxide, which was used in the first initial stage.

[0087] The target residual concentration of chlorine dioxide in the treated fluid or wastewater depends on the expected storage duration before reuse, for example, as a working fluid. For example (and as shown in FIGS. 7-9), in the case of direct use as hydraulic fracturing water in a hydraulic fracturing system, the required residual chlorine dioxide content in the fluid 200 exiting the system is from about 0.1 to 20 ml / l, preferably from about 0.5 to 5 ml / l (see paragraph 64 and 65). In another example (see, for example, FIGS. 2-6), if the treated fluid is intended to be stored in a container 50 for several days or longer, the target residual concentration of chlorine dioxide should be from about 5 to 50 ml / l, preferably about from 20 to 50 ml / l, including any and all relevant ranges and sub-ranges (see paragraph 64 and 65). As discussed above, in exemplary embodiments of the invention, during the last step of the processing process, chlorine oxide 30 contains only chlorine dioxide 30a. During this processing step, chlorine oxide 30 (in the form of chlorine dioxide 30a) and oxidizing agent 40 cannot be simultaneously added to stream 100.

[0088] In one or more embodiments of the invention, if the storage and processing system or tank 50 comprises a tank, pit, pond or settling basin, the total processing time required for the wastewater 15 to reach oxidation and / or disinfection is less than 24 hours, preferably less than 8 hours. In yet another embodiment, the total processing time necessary for the wastewater 15 to reach oxidation and / or disinfection is approximately less than 60 minutes, preferably approximately less than 15 minutes, if the system or vessel 50 is a pipe or a combination of pipe and tank, for example, used for on-the-fly operations (see, for example, FIGS. 1, 6-8) if the residence time is limited and the treated fluid 200 needs to be used immediately.

[0089] FIG. 2-5, various embodiments of a processing system 150 are shown. In FIG. 3, air injection is used to introduce the oxidizing agent 40 into the container 50 by means of a diffuser 70 and a pressurized source 71. In FIG. 4, a chemical tank and a pressurized source 80 are used to introduce oxidizing agent 40. FIG. 5, in-line diffuser 70 and pressure source 71 are used to introduce oxidizing agent 40 into stream 100. In some embodiments, a mechanical stirrer 92 is used. FIG. 6-8 (and also in FIG. 1), various embodiments of a processing system 250 are shown. In particular, in these embodiments, the treatment system 150 comprises an “in-line” treatment system 250, for example, an on-the-fly fracturing fluid treatment system or any other industrial water treatment system installed in-line for immediate use. In FIG. 6, oxidizing agent 40 from a source of chemicals 72 is introduced in-line using a venturi 20. In FIG. 7, a chemical tank 80 is used in-line to introduce oxidizing agent 40 to stream 100. In FIG. 8, air is introduced to the oxidizer 40 into the stream 100 by means of a diffuser 70 and a pressurized source 71. Although not shown in the drawings, the processing system 150/250 may also include a source, means for introducing caustic soda 90, and other processing methods waste water known in the art, for example, mechanical agitators, overflow systems, foam suppressants, electronic sensors and control devices.

[0090] As indicated above, in order to prepare chlorine dioxide suitable for use in this invention, any suitable method for preparing chlorine dioxide known in the art can be applied. In general, chlorine dioxide solutions can be prepared by treating chlorite saline solutions (e.g. NaClO ₂ ) with an acidic solution to prepare acidic solutions containing ClO ₂ , which can then be introduced into the water as a gas to prepare an aqueous ClO solution ₂ . Other precursors may also be used, for example sodium chlorate.

[0091] Various means are known in the art for the formation of chlorine dioxide and the corresponding chemicals of chlorine dioxide precursors, and one skilled in the art can choose suitable means and chemicals. Examples of chemical agents for the formation of chlorine dioxide are disclosed in US Pat. et al.) and US 6,645,457 (Mason et al.), the descriptions of which are incorporated herein by reference.

[0092] In preferred embodiments, the chlorine dioxide should be as pure as possible. In particular, chlorine gas should be present in the introduced chlorine dioxide gas at a level of about less than 5%, preferably about less than 0.5%. For example, in a preferred embodiment, the present invention provides a process comprising providing chlorine dioxide by using, for example, a device such as a chlorine dioxide generator, for example, as described and claimed in US Pat. No. 6,468,479, the disclosure of which is incorporated herein by reference . Chlorine dioxide is generated either directly in the form of gas, or preferably in the form of a mixture of chlorine dioxide with water (or other suitable carrier fluid). Preferably, this generator operates with an excess of sodium chlorite to reduce the likelihood of generating chlorine gas as an impurity. Other commonly used methods for the preparation of chlorine dioxide, for example, can be found in patent document US 2006/0068029 (U.S. Pat. Arr. No. 11/131021), the description of which is incorporated herein by reference. In addition, the generator preferably uses the wastewater 15 as a carrier fluid to generate chlorine dioxide and brings the chlorine dioxide gas into contact with the wastewater 15 under vacuum pressure, so that the chlorine dioxide gas is drawn into the wastewater 15 to form an aqueous solution of chlorine dioxide .

[0093] In some embodiments, the treated water is circulated in a closed system and re-purified on site in accordance with the methods and systems described herein until the contaminants are oxidized and the corresponding residual chlorine dioxide content is reached before being discharged systems 150. In other embodiments, after treatment with chlorine oxide 30 and a second oxidizing agent 40, the treated fluids remain in tank 50 for an appropriate period of time and so that solid particles can settle and free oil can be removed before reuse or release using wastewater treatment methods known in the art. In other embodiments, the process fluid is applied (or reused) immediately after treatment in oil production, fracturing, or other industrial applications. FIG. 9 schematically illustrates another embodiment of the invention.

[0094] Of course, the system and method described herein can be connected upstream or downstream with already installed devices or systems for treating or moving formation water. For example, the proposed processing system can be included in a system already installed at the site of oil and gas production. In addition, in exemplary embodiments and in accordance with FIG. 1, as one example, when the treated fluid 2d exits the vessel 104 and / or the treatment system, the concentration of biological contaminants, particle size, volatile compounds, TDS, and chemicals can be controlled. This control may be continuous or periodic. If the parameters of the fluid exiting the treatment system are not within a certain acceptable range, then it can again be supplied to the treatment system, and / or the amount of oxidizing agent and / or chlorine dioxide introduced into the treatment system can be changed. Similarly, in some embodiments, all or part of the stream flowing from the treatment system can be re-passed through the treatment system using one or more recirculation piping (not shown). Repeatedly passing a fluid stream through the system can provide a significant reduction in the concentration of contaminants. As shown, as one example, in FIG. 1, in some embodiments, a portion of the stream exiting the system can be mixed with a portion of the stream entering the inlet 17 of the processing system.

[0095] Although the above examples and description describe a substantially closed processing system, the systems and methods disclosed and claimed herein can also be used in the case of on-the-fly fracturing systems and methods when the treated water is used immediately and / or shortly after processing and fracturing (see FIGS. 6-8). For example, in one embodiment, the fracturing water injected into the subterranean formation can be treated using the methods disclosed herein, outside the oilfield, in front of the wellhead. In the case of such a system, the reservoir 50 (for example, fracturing reservoirs installed at the fracturing site or in the oil field) can be continuously filled with feed water, which must be treated before entering the well. This water may contain surface water, municipal water, produced water, return water, or any combination thereof (“mixed water”).

[0096] Furthermore, in alternative embodiments of the invention, the system or method described herein can be combined with one or more conventional or non-traditional biocides — oxidizable or non-oxidizable, to produce a synergistic biological effect. In addition, in the case of alternative embodiments, one skilled in the art will readily understand that additional processing processes known in the art may be included in the system in a batch or continuous mode, in-line or in another way (either before processing in accordance with this invention or after her). By way of example only and without being limited thereto, treatment processes may be included in the system to remove oil and / or particulate matter or, since foaming occurs, an antifoam agent compatible with chlorine dioxide may be included. Similarly, in some embodiments, the method and system disclosed herein can be attached to, or upgraded to, an existing regeneration system or treatment system, while they can operate in line continuously or in batch mode in selected quantities. In addition, one skilled in the art will readily understand that in one or more embodiments, an appropriate device and / or equipment for measuring and monitoring can be included in the method and system described herein.

[0097] In the case of embodiments disclosed herein, one of skill in the art will recognize that the residual chlorine dioxide content can be determined and / or calculated using the amperometric method II 4500 ClO2 E described in Standard Methods the Analysis of Water and Wastewater or its modified variants, and in the standard amperometric method II 4500 ClO2 E, the following calculations are used:

,

,

where titration A titrates chlorine and one fifth of the available chlorine dioxide, titration B titers four fifths of chlorine dioxide and chlorite, titration C titrates non-volatile chlorine (nitrogen gas cleans the chlorine dioxide sample), but is not used in the calculations, and titration D titrates chlorine. In other embodiments, the residual chlorine dioxide content can be determined by spectrometry or redox potential measurement (ORP) methods included herein, or by using modified versions thereof.

Part of the claims

[0098] Embodiments of the present invention in particular include the following.

1. A method of processing a water system, including:

ensuring the availability of an aqueous fluid volume having an initial oxidizing agent consumption;

introducing the oxidizing agent into the water volume at a flow rate preventing the release of volatile reducing agents in the form of gas from the water volume, the oxidizing agent being selected from the group consisting of oxygen, air, oxygen-enriched air, and a combination thereof;

combining the water volume and the oxidizing agent for a minimum residence time sufficient to reduce the initial consumption of the oxidizing agent to a reduced consumption of the oxidizing agent;

ensuring the presence of at least one chlorine oxide; and

combining the water volume and a certain amount of at least one chlorine oxide in an amount sufficient to eliminate the reduced consumption of an oxidizing agent, said at least one chlorine oxide being chlorine dioxide, chlorite, and a combination thereof.

2. The method according to claim 1, wherein the step of combining the volume of the aqueous fluid and a certain amount of at least one chlorine oxide includes the following steps:

a) introducing the first chlorine oxide into the water volume either before or essentially simultaneously with the step of introducing the oxidizing agent, wherein the first chlorine oxide contains sodium chlorite; and

b) introducing a second chlorine oxide into the water volume after the step of combining the water volume and the oxidizing agent during the indicated minimum residence time, wherein the second chlorine oxide contains chlorine dioxide, chlorite, or a combination thereof.

3. The method according to p. 2, in which sodium hydroxide is introduced before the step of introducing the oxidizing agent into the water volume, either in combination with sodium chlorite, or, as a separate feed, essentially simultaneously with it.

4. The method according to any one of paragraphs. 1-3, including the additional step of measuring and maintaining after processing the residual content of chlorine dioxide in the water volume of at least about 0.1 mg / L.

5. The method according to p. 4, in which the residual content of chlorine dioxide in the water volume is in the range from about 0.1 to about 50 mg / L.

6. The method according to any one of paragraphs. 2-5, which includes an additional step in which the solids formed in the water volume are precipitated or raised, and the solid particles are separated from the wastewater contained therein before the step of introducing the second chlorine oxide into the water volume.

7. The method according to any one of paragraphs. 1-6, in which the source of the water volume is selected from the group comprising a stream of aqueous fluid, a tank, a tank, a pit, a sludge basin or a reservoir for storing drainage water, a water treatment plant, a fracturing tank, or part of an equipment, pipeline, or tank, used for fracking or oil production.

8. The method according to any one of paragraphs. 1-6, in which the water system is selected from the group including hydraulic fracturing, oil production, water distribution systems, pipelines for moving fluids, wastewater treatment plants, storage tanks, food and beverage production lines, systems cutting fluids for machining or metal processing (MWF), coal and mineral sludge, metal leaching fluids, acid mine drainage or any water system contaminated biological substances or sulfur compounds.

9. The method according to any one of paragraphs. 1-8, which includes the step of generating an aqueous solution of chlorine dioxide using a chlorine dioxide generator that brings chlorine dioxide gas into contact with a portion of the treated water volume under vacuum pressure, so that the chlorine dioxide gas is drawn into the portion of the treated water volume to form an aqueous solution chlorine dioxide.

10. The method according to any one of paragraphs. 1-9, in which the water system contains one or more separators for removing from the water volume precipitated contaminants during treatment or after treatment, or before treatment.

11. The method according to any one of paragraphs. 1-10, in which the water volume is reduced, inactivated, destroyed, eliminated or removed pollution selected from the group including Ca, Mg, Na, Fe, Cl, Mn, CaClO ₃ , SO ₄ , Ba, hydrocarbons, total amount of dissolved solids, biological pollution, and combinations thereof.

12. A method of reducing, inactivating, destroying, removing or eliminating contaminants from an aqueous fluid selected from the group consisting of Ca, Mg, Na, Fe, Cl, Mn, CaClO ₃ , SO ₄ , Ba, hydrocarbons, total dissolved solids, biological pollution, and combinations thereof, comprising the steps of introducing an oxidizing agent and introducing at least one chlorine oxide, wherein said oxidizing agent is selected from the group consisting of oxygen, air, oxygen-enriched air and a combination thereof, and at least at least one chlorine oxide ybirayut from the group comprising chlorine dioxide, chlorite or combinations thereof.

13. The method according to p. 12, in which the step of introducing the specified at least one chlorine oxide includes the following steps:

a) introducing the first chlorine oxide into the aqueous fluid, either before or essentially simultaneously with the step of introducing the oxidizing agent, the first chlorine oxide containing sodium chlorite; and

b) introducing a second chlorine oxide into the aqueous fluid after the step of combining the aqueous fluid and the oxidizing agent, wherein the second chlorine oxide comprises chlorine dioxide, chlorite, or a combination thereof.

14. The method according to p. 13, in which, before the step of introducing the oxidizing agent into the aqueous fluid, sodium hydroxide is introduced either in combination with sodium chlorite or as a separate feed substantially simultaneously with it.

15. The method according to any one of paragraphs. 13-14, in which the second chlorine oxide is an aqueous solution of chlorine dioxide.

16. The method according to p. 15, further comprising the step of generating an aqueous solution of chlorine dioxide by using part of the treated aqueous fluid.

17. The method according to any one of paragraphs. 12-16, in which the oxidizing agent is introduced at a rate that prevents the release of volatile reducing agents in the form of gas from the aqueous fluid.

18. The method according to any one of paragraphs. 12-17, which includes an additional step of measuring and maintaining after processing the residual chlorine dioxide content in the aqueous fluid in the range of about 0.1 to 50 mg / L.

19. The method according to any one of paragraphs. 12-18, in which the source of the aqueous fluid stream or the water volume is selected from the group including a tank, tank, pit, sludge basin or reservoir for storing drainage water, a water treatment plant, a fracturing tank, or part of an equipment, pipeline, or tank, used for fracking or oil production.

20. A method of processing an aqueous system, including:

introducing the oxidizing agent into the water volume with a flow rate preventing the release of volatile reducing agents from the water volume in the form of gas, before introducing chlorine dioxide into the volume, the oxidizing agent being selected from the group consisting of oxygen, air, oxygen-enriched air, and combinations thereof, wherein the oxidizing agent provides a synergistic oxidative effect in the presence of chlorine dioxide, so that chlorine dioxide is introduced in significantly reduced amounts compared to a predetermined consumption of chlorine dioxide.

21. The method according to p. 20, comprising the additional step of introducing sodium chlorite into the specified volume before the step of introducing the oxidizing agent.

22. A method of processing an aqueous system, including:

ensuring the availability of a water volume having an initial consumption of an oxidizing agent;

introducing an oxidizing agent containing oxygen, air, oxygen-enriched air, or a combination thereof, into the water volume with a flow rate preventing the release of volatile reducing agents in the form of gas from the water volume;

introducing sodium chlorite into the water;

the combination of the water volume, the oxidizing agent and sodium chlorite, thus reducing the initial consumption of the oxidizing agent to a reduced consumption of the oxidizing agent;

introducing a separate portion of chlorine dioxide into the water volume in an amount sufficient to eliminate the reduced consumption of oxidizing agent and to ensure that the residual chlorine dioxide content in the water volume is at least about 0.1 mg / L.

23. A method of processing an aqueous system, including:

ensuring the availability of a water volume having an initial consumption of an oxidizing agent;

introducing an oxidizing agent containing oxygen, air, oxygen-enriched air, ozone, or a combination thereof, into the water volume at a rate that prevents the release of volatile reducing agents in the form of gas from the water volume;

combining the water volume and the oxidizing agent for a minimum residence time sufficient to reduce the initial consumption of the oxidizing agent to a reduced consumption of the oxidizing agent;

ensuring the presence of at least one chlorine oxide; and

combining the water volume and a quantity of at least one chlorine oxide in an amount sufficient to eliminate the reduced consumption of an oxidizing agent, wherein said at least one chlorine oxide contains chlorine dioxide, chlorite or a combination thereof, provided that if at least one chlorine oxide contains chlorine dioxide, the water volume does not contain residual ozone.

24. A method of treating wastewater, comprising the following steps:

introducing a wastewater stream into a fluid treatment system comprising at least one first treatment section, at least one second treatment section, and at least one third treatment section;

providing a flow of wastewater to at least one first fluid conduit to said at least one first treatment section; recovering at least a portion of the wastewater from said at least one first treatment section using at least one second fluid conduit;

introducing air into the extracted part of the wastewater through at least one point of in-line treatment with air in said at least one second fluid conduit under conditions sufficient to completely mix the air in the wastewater, and introducing sodium chlorite into the extracted part of the wastewater water through said at least one point in-line treatment with sodium chlorite in said at least one second fluid conduit to prepare treated wastewater;

recycling the treated wastewater back to said at least one first treatment section;

allowing precipitation or lifting of solid particles formed in the treated water in said at least one first treatment section, and separating the solid particles from the treated wastewater contained in this section;

discharging treated wastewater from said at least one first treatment section to said at least one second treatment section using at least one third fluid conduit, wherein before draining wastewater to said at least one second processing section chlorine dioxide gas is introduced through at least one in-line treatment point in said at least one third fluid conduit at a certain flow rate sufficient to provide a residual content the introduction of chlorine dioxide in treated wastewater;

providing the possibility of deposition or lifting of solid particles formed in the treated wastewater in said at least one second treatment section, and separating solid particles from the wastewater contained in this section;

providing a flow of wastewater from the at least one second treatment section to the at least one first outlet of the lower discharge, allowing the outlet to the specified at least one third processing section;

providing the possibility of sedimentation or lifting of solid particles formed in wastewater in said at least one second treatment section, and separating solid particles from wastewater contained in this section;

and providing a flow of wastewater from said at least one third treatment section to at least one first outlet of the upper discharge in fluid communication with the fourth treatment section, tank, or clean reservoir.

25. The method according to p. 24, in which sodium hydroxide is introduced into the wastewater through at least one second fluid conduit, either in combination with sodium chlorite, or as a separate feed substantially simultaneously with it.

26. The method according to any one of paragraphs. 24-25, wherein said at least one first processing section provides a first residence time of about 15 to 60 minutes.

27. The method according to any one of paragraphs. 24-26, in which the oxidizing agent is introduced at a rate that prevents the release of volatile reducing agents in the form of gas from wastewater.

28. The method according to any one of paragraphs. 24-27, in which the specified at least one first processing section contains one or more separators for removing from the specified at least one first processing section of precipitated contaminants.

29. The method according to any one of paragraphs. 24-27, wherein said at least one first treatment section comprises one or more removal devices for removing contaminants from the surface of the wastewater contained in said at least one first treatment section.

30. The method according to any one of paragraphs. 24-29, in which the specified at least one second processing section contains one or more devices for removing floating contaminants from the surface of the wastewater contained in the specified at least one second processing section.

31. The method according to any one of paragraphs. 24-30, wherein said at least one second processing section provides a second residence time of from about 10 to 30 minutes.

32. The method according to any one of paragraphs. 24-31, wherein said at least one third processing section provides a third residence time of about 10 to 30 minutes.

33. The method according to any one of paragraphs. 24-32, wherein said at least one third treatment section comprises a separator for removing precipitated contaminants from said at least one third processing section.

34. The method according to any one of paragraphs. 24-33, wherein the wastewater is removed by pump from the first treatment section through the at least one second fluid pipe, passed through at least one venturi and returned to the first treatment section.

35. The method according to any one of paragraphs. 24-34, in which air is introduced into a second fluid conduit through a venturi.

36. The method according to p. 35, in which a solution of sodium chlorite, a combination of sodium chlorite and sodium hydroxide, or both of these chemicals as separate portions, are introduced into the second fluid conduit through the at least one Venturi tube.

37. The method according to any one of paragraphs. 24-36, wherein the wastewater stream entering the fluid treatment system has a first oxidizer consumption, and said treated wastewater entering the at least one second treatment section has a second oxidizer consumption.

38. The method according to any one of paragraphs. 24-37, in which part of the wastewater recovered from the first treatment section using the at least one second fluid conduit is recovered from a level of about 20% of the bottom of said at least one first treatment section.

39. The method according to any one of paragraphs. 24-38, wherein the treated wastewater is discharged from said at least one second fluid conduit substantially along a midline of said at least one first treatment section.

40. The method according to any one of paragraphs. 24-39, which removes contaminants selected from the group consisting of Ca, Mg, Na, Fe, Cl, Mn, CaClO ₃ , SO ₄ , Ba, hydrocarbons, total dissolved solids or biological pollution.

41. The method according to p. 40, in which the content of calcium and magnesium in the treated fluid, set as CaCO ₃ , is reduced to a value of less than approximately 2200 mg / L.

42. The method according to p. 40, in which the content of calcium and magnesium in the treated fluid, set as CaCO ₃ , is reduced to 93%.

43. The method according to any one of paragraphs. 24-39, in which sulfur compounds, bacteria or combinations thereof are reduced, inactivated, destroyed or eliminated in an aqueous volume.

44. The method according to any one of paragraphs. 24-43, in which the wastewater stream is produced water obtained at the site of oil and gas production.

45. The method according to any one of paragraphs. 24-44, in which the residual chlorine dioxide content in the treated wastewater in the second treatment section is in the range of from about 0.1 to about 50 mg / L.

46. The method according to any one of paragraphs. 24-45, in which the source of the wastewater stream is selected from the group comprising a stream of aqueous fluid, a tank, a tank, a pit, a settling basin or a reservoir for storing drainage waters, a water treatment plant, a fracturing tank, or part of an equipment, pipeline, or tank used for fracturing or oil production.

47. The method according to any one of paragraphs. 24-46, in which the first processing section is a tank selected from the group including a storage tank, a fracturing tank, or another in-situ tank used for fracturing or oil recovery.

48. The method according to any one of paragraphs. 24-47, in which the second and third processing section are installed in one tank selected from the group including a storage tank, a fracturing tank or another in-situ tank used for fracturing or oil production.

49. The method according to any one of paragraphs. 24-48, which includes the step of generating an aqueous solution of chlorine dioxide using a chlorine dioxide generator, which brings chlorine dioxide gas into contact with a portion of the treated wastewater stream under vacuum pressure, so that the chlorine dioxide gas is drawn into part of the wastewater stream to form aqueous chlorine dioxide solution.

50. A fluid processing system configured to perform a method according to any one of paragraphs. 24-49.

51. A fluid processing system for continuous use at a location of a hydrocarbon production well, comprising:

at least one first processing section, at least one second processing section and at least one third processing section;

at least one first fluid conduit for flowing a wastewater stream with an initial consumption of an oxidizing agent into at least one first treatment section having at least one outlet that is in fluid communication with it;

at least one second fluid conduit for circulating wastewater from the at least one first treatment section having at least one outlet and at least one inlet in communication therewith with the possibility of transferring the fluid;

at least one first eductor in fluid communication with at least one second fluid conduit and at least one oxidizer source and for introducing at least one oxidizer into at least one second fluid conduit media in controlled quantities and with controlled flow;

at least one second eductor in fluid communication with at least one second fluid conduit and at least one chlorine oxide source and for introducing at least one first chlorine oxide into at least one second fluid conduit in controlled amounts;

at least one third fluid conduit for conveying wastewater from the at least one first treatment section to the at least one second treatment section, the at least one third fluid conduit being in fluid communication media with at least one outlet at least one first processing section and with at least one inlet at least one second processing section;

at least one third eductor in fluid communication with at least one third fluid conduit and at least one chlorine dioxide source and for introducing chlorine dioxide into the at least one third fluid conduit in controlled quantities and with controlled consumption;

wherein the first treatment section comprises at least one removal device, at least one separator for removing contaminated sediments from the at least one first treatment section, and has a residence time of from about 15 minutes to about 60 minutes;

the second processing section contains at least one removal device, at least one outlet outlet of the lower drain, providing release into at least one third of the processing section, and has a residence time of from about 10 minutes to about 30 minutes;

and the third treatment section contains at least one separator designed to remove precipitated contaminants from the at least one third treatment section and at least one outlet outlet of the overflow and has a residence time of from about 10 minutes to about 30 minutes.

52. The system of claim 51, wherein the first eductor and the second eductor are combined and configured to introduce at least one oxidizing agent before or at the same time as introducing at least one chlorine oxide.

53. The system of claim 52, wherein the oxidizing agent is selected from the group consisting of oxygen, air, oxygen enriched air, and combinations thereof.

54. The system according to any one of paragraphs. 52-53, in which at least one first chlorine oxide contains an aqueous solution of sodium chlorite.

55. System according to any one of paragraphs. 52-54, in which a controlled flow of oxidizing agent prevents the release of volatile reducing agents in the form of gas from wastewater.

56. System according to any one of paragraphs. 52-55, in which the first processing section is a tank, tank or piece of equipment or a tank used for fracturing or oil production.

57. The water system according to any one of paragraphs. 52-56, in which the residual content of chlorine dioxide in the treated wastewater in the second treatment section is in the range from about 0.1 to about 50 mg / L.

58. The water system according to any one of paragraphs. 52-57, in which the first, second and third eductors are a venturi.

59. A method for treating wastewater, comprising the following steps:

introducing a wastewater stream into a fluid treatment system comprising at least one first treatment section, at least one second treatment section, and at least one third treatment section;

providing a flow of wastewater to the at least one first fluid conduit to the at least one first treatment section; recovering at least a portion of the wastewater from the at least one first treatment section using at least one second fluid conduit;

introducing the oxidizing agent into the extracted part of the wastewater through at least one point of the in-line treatment with the oxidizing agent in at least one first fluid conduit under conditions sufficient to completely mix the oxidizing agent in the wastewater and at a controlled flow rate, the oxidizing agent being selected from a group comprising oxygen, air, oxygen-enriched air, and combinations thereof, and introducing at least one chlorine oxide into the extracted portion of the wastewater through at least one in-line treatment point and using chlorine oxide in at least one first fluid conduit to prepare treated wastewater;

recycling the treated wastewater back to the at least one first treatment section, allowing precipitation or lifting of solid particles formed in the treated water in at least one first treatment section, and separating the solid particles from the treated wastewater contained in this section;

draining the treated wastewater from at least one first treatment section into at least one second treatment section using at least one third fluid conduit,

moreover, before discharge into at least one second treatment section, chlorine dioxide gas is introduced through at least one in-line treatment point in at least one second fluid conduit at a certain flow rate to ensure a residual chlorine dioxide content in the treated wastewater ;

allowing sedimentation or recovery of solid particles formed in the treated wastewater in at least one second treatment section, and separating solid particles from the wastewater contained therein;

providing a flow of wastewater from the at least one second treatment section to the at least one first outlet of the lower discharge, allowing the discharge into at least one third of the treatment section; allowing sedimentation or recovery of solid particles formed in the wastewater in at least one second treatment section, and separating solid particles from the wastewater contained in this section;

providing a flow of wastewater from at least one third treatment section to at least one first outlet of the upper drain to at least one fourth treatment section, tank or clean tank.

EXAMPLES

[0099] To facilitate understanding of the present invention, the following embodiments of the present invention are provided. It should be understood that this does not lead to any limitation of the scope of the invention, it being understood that the following examples do not limit or determine the scope of the invention.

[00100] In the following examples, the effect of chlorine dioxide on wastewater obtained from oil fields was studied with and without oxygen treatment.

[00101] Example 1. The following experiment was conducted to determine how strongly the addition of air or oxygen affects the processing of a sample of field wastewater using chlorine dioxide (and / or chlorite). The results of this experiment show that the combination of air or oxygen with chlorine dioxide or chlorite gives an unexpected useful result, namely that the dose of oxidizing agent required to oxidize the sulfides present in wastewater from oil fields is significantly reduced. In addition, it was unexpectedly found that the combination of air or oxygen with chlorine dioxide provides the destruction of bacteria at significantly reduced dosages. In contrast, adding only air or oxygen over an acceptable period of time is not enough to remove sulfides from wastewater or destroy the bacteria in those waters, and adding alternative oxidizing agents (i.e. nitrogen) does not produce the same synergistic effect.

[00102] In each of the following experiments 1 (A) to 1 (G), a water sample was used containing 10 percent solids with an amount of sulfide in the aqueous phase of 110 mg / L and having a pH value of 8.2. Particulate matter consists of biomass, inorganic materials, hydrocarbon and insoluble sulfides with a concentration of 82.5 mg / kg. Sulphide-reducing bacteria and common aerobic bacteria were cultured from the sample, with growth of more than 10 ⁶ CFU / ml. The sample (solution and solid particles) has a dark color.

[00103] First, the following series was performed for experimental control.

[00104] Control A. A portion of the sample (200 ml) was purified with chlorine dioxide (335 mg / L) for more than 15 minutes with stirring to obtain a residual content (less than 1.0 mg / L) of chlorine dioxide. The sample quickly changes color from dark to brown or orange, while insoluble solids quickly settle and form flakes such as iron. In addition, a slight gloss of hydrocarbon was observed on the surface of the treated sample. No other changes in the appearance of the treated fluid were observed for 5 minutes. Solids (sediment) and fluid were analyzed for sulfide content using a Garrett gas analyzer. No detectable sulfides were found in solids and fluids. Sulfur-containing bacteria and ordinary aerobic bacteria were cultured from the sample, and no bacterial growth was observed.

[00105] Control B. A portion of the sample (200 ml) was purified using chlorine dioxide (230 mg / L) for 5 minutes with stirring. The sample quickly changes color from dark to brown or orange, while insoluble solids quickly settle and form flakes such as iron. No other changes in the appearance of the treated fluid were observed for 5 minutes. Solids (sediment) and fluid were analyzed for sulfide content using a Garrett gas analyzer. In the fluid and sediment found 31 mg / l and 51 mg / kg, respectively. There was no residual chlorine dioxide. Sulfur-containing bacteria and ordinary aerobic bacteria were cultured from the sample, with bacterial growth of more than 10 ⁶ CFU / ml.

[00106] Control C. A portion of the sample (200 ml) was purified using chlorine dioxide (420 mg / L chlorite — 560 mg / L as sodium chlorite) with stirring. The sample quickly changes color from dark to brown or orange, insoluble solids quickly settle, and flakes such as iron form within ten minutes. In addition, a slight gloss of hydrocarbon was observed on the surface of the treated sample. No other changes in the appearance of the treated fluid after 10 minutes were observed. Particulate matter and fluid were analyzed for sulfide content using a Garrett gas analyzer. No detectable sulphides were found in the fluids, but the sulphide content of the solids was approximately 15 mg / L. Sulfur-containing bacteria and ordinary aerobic bacteria were cultured from the sample, with growth of more than 10 ⁶ CFU / ml.

[00107] Control D. Using a thin diffuser, a portion of the sample (200 ml) was bubbled with air for 30 minutes at a rate of 2 tbsp. l / min Within 30 minutes, the sample changes color from dark to gray. Solids (sediment) and fluid were analyzed for sulfide content using a Garrett gas analyzer. The fluid contains 60 mg / L sulfide; the solids contain 75 mg / L sulfide. Sulfur-containing bacteria and ordinary aerobic bacteria were cultured from the sample, with growth of more than 10 ⁶ CFU / ml.

[00108] Then, in the three systems (air — chlorine dioxide, nitrogen — chlorine dioxide, and air — chlorite), the following three bubbling experiments were performed.

[00109] Experiment E. Using a thin diffuser, part of the sample (200 ml) was bubbled with air for 4 minutes at a rate of 2 tbsp. l / min At the same time, they began to add and over a period of 5 minutes a dose of 230 mg / L of chlorine dioxide was added, and during the last minute, dosing was carried out without air sparging. In this example, ClO _{2 is} added at a relatively low rate with such a volume and air flow rate that chlorine dioxide is not removed before it reacts. The sample quickly changes color from dark to brown or orange, while insoluble solids quickly settle, and after the bubbling stops, flakes such as iron are formed. No other changes in the appearance of the treated fluid were observed for 5 minutes. Solids (sediment) and fluid were analyzed for sulfide content using a Garrett gas analyzer. No detectable sulfides were present in particulate matter or fluid. Sulfur-containing bacteria and ordinary aerobic bacteria were cultured from the sample, and no bacterial growth was observed.

[00110] Experiment F. Using a thin diffuser, a portion of the sample (200 ml) was bubbled with nitrogen for 4 minutes at a rate of 2 tbsp. l / min At the same time, they began to add and over a period of 5 minutes a dose of 230 mg / L of chlorine dioxide was added, and during the last minute, dosing was carried out without nitrogen bubbling. The sample quickly changes color from dark to brown or orange, while insoluble solids quickly settle, and after the bubbling stops, flakes such as iron are formed. No other changes in the appearance of the treated fluid were observed for 5 minutes. Solids (sediment) and fluid were analyzed for sulfide content using a Garrett gas analyzer. The residual sulfide content in the fluid and solid particles was 7 mg / L and 160 mg / L, respectively. Sulfur-containing bacteria and ordinary aerobic bacteria were cultured from the sample, with bacterial growth of more than 10 ⁶ CFU / ml.

[00111] Experiment G. Using a thin diffuser, a portion of the sample (200 ml) was bubbled with air for 15 minutes at a rate of 2 tbsp. l / min At the same time, they began to add and over a period of 5 minutes a dose of 300 mg / L of chlorite was added (402 mg / L as sodium chlorite). The sample changes color from dark to brown or orange, while insoluble solids quickly settle, and after the bubbling stops, flakes such as iron are formed. No other changes in the appearance of the treated fluid were observed for 15 minutes. Solids (sediment) and fluid were analyzed for sulfide content using a Garrett gas analyzer. No detectable sulfides were present in particulate matter or fluid. Sulfur-containing bacteria and ordinary aerobic bacteria were cultured from the sample, with bacterial growth of more than 10 ⁶ CFU / ml.

[00112] In the following examples, the unexpected synergistic effect of processing in a closed system a storage tank filled with wastewater from an oil field using chlorine dioxide and oxygen was studied. On two systems (only air - chlorine dioxide and air - chlorite - chlorine dioxide) the following experiments were carried out with bubbling.

[00113] Example 2. The contents of a tank containing 30,000 barrels of formation fresh water and return water were analyzed. The tank contained 16,000 mg / L dissolved solids, 10 ⁶ CFU / ml bacteria and 40 mg / L sulfides in a homogenized fluid with a pH of 7.8. It has been determined that for this process fluid, the consumption of chlorine dioxide is 180 mg / L. It was determined that 630 gallons of 50 percent sodium hydroxide was required to maintain pH.

[00114] The tank was equipped with a chlorine dioxide generator (see, for example, US Pat. No. 6,468,479). An example of a generator, although not restrictive, is the Saber BB series portable DiKlor® mobile generation system, which has a capacity of 24,000 pounds per day of continuous production. This autonomous system has a distribution system that allows it to circulate fluids in the tank. More precisely, a carrier fluid stream was extracted from the tank, which was then pumped through a chlorine dioxide generator using a centrifugal pump at a rate of 320 gallons per minute. The generator is installed so that the suction of the working fluid flow occurs in the lower part of the tank. The drained solution containing chlorine dioxide and / or air was returned to the tank with a movable rod with spray tips and released to its bottom. (See FIGS. 5 and 8). The spray tip bar was continuously moved around the tank at a speed of 50 feet per minute.

[00115] Sodium hydroxide was added to the tank with an amount of sodium chlorite sufficient to absorb about 10 percent of the theoretical consumption of chlorine dioxide. In this specific example and in accordance with calculations known in the art, the amount of sodium chlorite required to absorb 10% of the theoretical consumption of chlorine dioxide was a dose of chlorite of approximately 23 mg / L. Sodium hydroxide and chlorite with air were added over sixty minutes at a rate of 125 standard cubic feet per minute. In this embodiment, air was introduced through a venturi. At the end of this 60-minute period, air intake was stopped and the consumption of chlorine dioxide was re-checked. It was 27 mg / l. Then, using a venturi, chlorine dioxide was added at an appropriate flow rate to obtain a dose of 47 ml / g over 30 minutes. During the chlorine dioxide phase, no air was introduced.

[00116] The obtained transparent fluid had an orange (brown) precipitate and a thin flocculant layer located on top, the composition of which was determined to contain 98% inorganic material and 2% hydrocarbons. A residual chlorine dioxide content of 8 mg / L was found in the fluid. Fluid, sediment and flocculant were analyzed using a Garrett gas analyzer. It turned out that they do not contain sulfides. In the analysis of culture cultures of bacteria were not found. The fluid was analyzed to determine whether it is suitable for "gelation" for use in fracturing. The fluid easily formed a gel and cross-links. The result of this method was a 75 percent reduction in the amount of chlorine dioxide needed to obtain the target residual chlorine dioxide content and to prevent bacterial growth.

[00117] Example 3. The contents of a tank containing 30,000 barrels of formation fresh water and return water were analyzed. The tank contained 16,000 mg / L dissolved solids, 10 ⁶ CFU / ml bacteria and 40 mg / L sulfides in a homogenized fluid with a pH of 7.8. It was determined that for this fluid, the consumption of chlorine dioxide is 180 mg / L. The tank was equipped with a chlorine dioxide generator so that the suction of the working fluid flow occurred in the lower part of the tank. The drained solution containing chlorine dioxide and / or air was returned to the tank with a discharge rod to the bottom of the tank using a movable rod with spray tips. The spray tip bar was continuously moved around the tank at a speed of 50 feet per minute. Fluid was removed from the tank and pumped through a chlorine dioxide generator using a centrifugal pump at a rate of 320 gallons per minute.

[00118] In this example, chlorite in the form of sodium chlorite was not added directly to the system. Instead, chlorine dioxide (which turned into chlorite) was added to the tank first, then air, and finally a second dose of chlorine dioxide, as described below. More specifically, 1) from the start of the time (0), chlorine dioxide was added over the first 10 minutes to provide 20% of the total dose; 2) from the 10th minute to the 30th minute, the solution was pumped through a closed system; 3) air was added from the 10th to the 60th minute; and 3) from the 60th to the 80th minute, the remaining 80% of chlorine dioxide was introduced into the tank. In general, the tank was cleaned with chlorine dioxide at a concentration of 110 mg / L over a total (but not continuous) 50-minute period. As for stage 2, the specialist in the art will understand that if you use a tank of large capacity, you must be careful not to get "hot spots", and take care that the chlorine dioxide is a little dispersed.

[00119] In step 3, air was added separately at a rate of 100 standard cubic feet per minute through a venturi to the tank 250 separately in a time interval of 30 to 60 minutes. In alternative embodiments, reduced doses of ClO ₂ with air could be added, depending on the size and depth of the vessel, as well as the flow rate. Sodium hydroxide was added at the same time to maintain a stable pH value. After processing, a fluid analysis was performed. The obtained transparent fluid had an orange (brown) precipitate and a thin flocculant layer located on top, the composition of which was determined to contain 98% inorganic material and 2% hydrocarbons. A residual chlorine dioxide content of 12 mg / L was found in the fluid. Fluid, sediment and flocculant were analyzed using a Garrett gas analyzer. It turned out that they do not contain sulfides. In the analysis of culture cultures of bacteria were not found. The fluid was analyzed to determine whether it is suitable for "gelation" for use in fracturing. The fluid easily formed a gel and cross-links. The result of this method was an approximately 40 percent reduction in the amount of chlorine dioxide necessary to obtain the target residual chlorine dioxide content and to prevent bacterial growth.

[00120] Example 4. The reservoir contained 4200 gallons of produced water. The homogenized fluid was analyzed and determined that the total solids content in it was 23,000 mg / L, the bacteria content was 104 CFU / ml, the sulfide content was 175 mg / L, and the pH was 7.8. It was determined that the consumption of chlorine dioxide for this fluid is 580 mg / L. The tank was equipped with a chlorine dioxide generator so that the suction of the working fluid flow occurred in the lower part of the tank. The drained solution containing chlorine dioxide and / or air was returned to the tank along the bottom of the tank using a perforated pipe. Fluid was removed from the tank and circulated through a chlorine dioxide generator using a centrifugal pump at a rate of 320 gallons per minute.

[00121] As in Example 3, chlorine dioxide was added to the tank first through a venturi 320, then air, and finally a second dose of chlorine dioxide, as described below. More specifically, 1) from the beginning of the countdown (0), chlorine dioxide was added during the first minute to provide 20% of the total dose; 2) from the 6th minute to the 10th minute, the remaining 80% of chlorine dioxide was introduced into the tank. In general, the tank was cleaned with a concentration of 310 mg / l of chlorine dioxide over a total (but not continuous) 5-minute period. In the period from the 1st to the 6th minute, air was added through the venturi to the tank at a rate of 50 standard cubic feet per minute. Sodium hydroxide was added at the same time to maintain a stable pH value. After processing, a fluid analysis was performed. The obtained transparent fluid had an orange (brown) precipitate and a thin flocculant layer located on top, the composition of which was determined to contain 96% inorganic material and 4% hydrocarbons. A residual chlorine dioxide content of 7 mg / L was found in the fluid. Fluid, sediment and flocculant were analyzed using a Garrett gas analyzer. It turned out that they do not contain sulfides. In the analysis of culture cultures of bacteria were not found. The result of this method was an approximately 47 percent reduction in the amount of chlorine dioxide needed to obtain the desired residual chlorine dioxide content and to prevent bacterial growth.

[00122] Example 5. The reservoir contained 4200 gallons of produced water. The homogenized fluid was analyzed and determined that the total solids dissolved in it was 23,000 mg / L, the bacteria content was 104 CFU / ml, the sulfide content was 175 mg / L, with a pH of 7.8. It was determined that the consumption of chlorine dioxide for this fluid is 580 mg / L. The tank was equipped with a chlorine dioxide generator so that the suction of the working fluid flow occurred from the lower end of the tank. The drained solution containing chlorine dioxide and / or air was returned to the tank along the bottom of the tank using a perforated pipe. Fluid was removed from the tank and circulated through a chlorine dioxide generator using a centrifugal pump at a rate of 320 gallons per minute.

[00123] In this example, chlorite was administered directly at a rate such that a dosage of 120 mg / L was reached within the first minute. Chlorine dioxide was also administered at a rate such that a dose of 210 ml / g was obtained over a total period of 5 minutes. Specifically, chlorine dioxide was added from the start of the countdown (0) to the first minute (1), and then again from the sixth minute (6) to the tenth minute (10). In the time interval from the beginning of the 9th minute countdown, air was added to the tank at a rate of 50 standard cubic feet per minute through a venturi. Sodium hydroxide was added at the same time to maintain a stable pH value. After processing, a fluid analysis was performed.

[00124] The treated clear fluid had an orange (brown) precipitate and a thin flocculant layer located on top, the composition of which was determined to contain 96% inorganic material and 4% hydrocarbons. A residual chlorine dioxide content of 7 mg / L was found in the fluid. Fluid, sediment and flocculant were analyzed using a Garrett gas analyzer. It turned out that they do not contain sulfides. In the analysis of culture cultures of bacteria were not found. The result of this method was an approximately 43 percent reduction in the amount of chlorine oxides needed to obtain the desired residual chlorine dioxide content and to prevent bacterial growth.

[00125] The following experimental results show that the combination of oxidizing agent 40 (air or oxygen) with chlorite 30b, followed by the introduction of chlorine dioxide 30a, provides an unexpected useful result, which is a significant reduction in the content of unwanted contaminants in commercial wastewater (or in produced water) ), including Ca, Mg, Na, Fe, Cl, Mn, TDS, CaClO ₃ , SO ₄ , Ba, oils, greases, and bacterial contamination, so that the treated fluids are suitable for reuse as fluids for hydraulic fractures wa.

[00126] Example 6. The sequence of processing processes is applied to a typical reservoir fluid (2) obtained in North Texas. Using a circulation pump (3), a fluid with a constant flow rate of six barrels per minute is pumped into a fracturing tank (first fracturing tank 101) with a capacity of 500 barrels. About four barrels per minute of fluid are recovered from a level of 2 feet above the bottom of the first fracturing tank 101. The fluid 2a is passed through a venturi 4, in which air 40, sodium chlorite 30b and sodium hydroxide 90 are added to the fluid stream. The fluid stream 2a, again entering the first fracturing tank 101 and containing air 4, chlorite 30b and caustic soda 90, is introduced along the axis line 8a of the container 101 by means of a distribution rod 19 moving along the length of the container 101. In this example, chlorite 30b is introduced to give a dosage of 50 mg / L, and an oxidizing agent (40) is added to obtain a dosage of 400 mg / L. To remove the floating material, a skimmer (6) is installed in the upper part of the first fracturing tank (101).

[00127] The fluid 2a is withdrawn to the second fracturing tank 102 through a drain hole located approximately 2 feet higher than the bottom of the first fracturing tank 101. Fluid 2a is introduced into a second fracturing tank 102 at a level of about 2 feet. Chlorine dioxide 30a is introduced into the fluid stream between the first fracturing tank 101 and the second fracturing tank 102. In this example, chlorine dioxide 30a is administered to give a dosage of 25 mg / L. The fluid 2b from the bottom of the second fracturing tank 102 is discharged into the third fracturing tank 103. The fluid 2c from the third fracturing tank 103 is poured into a clean reservoir 104.

[00128] In this example, the formation fluid 2 flowing into the first fracturing tank 101 initially contained approximately 1 volume percent oil hydrocarbon. The free hydrocarbon in the first fracturing vessel 101 is preferably recovered on the surface. In a second fracturing tank 102, iron sulfide (FeS), oxidized with chlorine dioxide, reacts to form iron trihydroxide. The low-density solids resulting from this reaction and the additional hydrocarbons released were removed in a second fracturing tank by removing the top layer. High density solid particles formed as part of this process were deposited on the bottom of the second and third tanks. The fluid from the third tank 103 was poured into a clean tank 104. The treated fluid 2d was pumped out of a clean tank 104 for subsequent storage. The residual chlorine dioxide content of the treated fluid was 20 mg / L. Tables 1A-1C show the results obtained using the above method and the above system.

[00129] Example 7. The sequence of processing processes used for a typical reservoir fluid obtained in the Perm basin. Using a pump, a fluid with a flow rate of about six barrels per minute is pumped from the group of six storage tanks 500 to a fracturing tank 101 with a capacity of 500 barrels. Six fracturing storage tanks 500 are filled by truck from the field. About four barrels per minute of fluid are recovered from a level of 2 feet above the bottom of the first fracturing tank 101. The fluid 2a is passed through a venturi 4, in which air 40, sodium chlorite 30b and sodium hydroxide 90 are added to the fluid stream. The fluid stream, again entering the first fracturing tank and containing air 40, chlorite 30b and caustic soda 90, injected along the center line of the first fracturing vessel 101 using a distribution rod 19 moving along the length of the vessel 101. In this example, chlorite 30b is introduced to give a dosage of 50 mg / L, and oxidizing agent 40 is added to give a dosage of 400 mg / L (for example, 2200 mg / l of air). To remove the floating material, a skimmer 6 is installed in the upper part of the tank 101.

[00130] The fluid is withdrawn into the second fracturing tank 102 through a drain hole located approximately 2 feet higher than the bottom of the first fracturing tank 101, while the fluid is introduced into the second fracturing tank 102 at a level of approximately 2 feet. Chlorine dioxide 30a is introduced into the fluid stream between the first fracturing tank 101 and the second tank 102. In this example, chlorine dioxide 30a is administered to give a dosage of 25 mg / L. The fluid 2b from the bottom of the second tank 102 is discharged into the third tank 103. The fluid 2c from the third tank 103 is poured into a clean tank 104.

[00131] The free hydrocarbon in the first container 101 is preferably recovered on the surface. In a second container 102, iron sulfide, oxidized with chlorine dioxide, reacts to form iron trihydroxide. Solid particles of low density formed as a result of this reaction, and the released hydrocarbons were removed by removing the upper layer in this tank. The resulting high-density solid particles were deposited on the bottom of the second and third sections (containers). The fluid from the third section / container 103 was poured into a clean reservoir 104. The fluid 2d was pumped out of the clean reservoir 104 for subsequent storage. The residual chlorine dioxide content of the treated fluid was 20 mg / L.

[00132] In this example, the proportion of petroleum hydrocarbon in scoop samples of the incoming fluid was 60 ppmv. However, this measurement was inaccurate due to the properties of freight vehicles. Some arriving trucks did not have a significant hydrocarbon content, while others contained a few percent due to accumulations of hydrocarbons entering the system. A large amount of hydrocarbon, corresponding to 1.72% of the total fluid supply, was removed from the first and second tanks by removing floating contaminants. There was no noticeable hydrocarbon content in the third fracturing tank, and scoop fluid samples in the discharge from the last tank showed an average total hydrocarbon content of 45 ppm.

[00133] Tables 2A-2C show the results obtained from this treatment.

[00134] The process of the present invention has surprisingly proven to be cost-effective in removing contaminants from highly contaminated hydrocarbon containing formation water streams. As can be seen from tables 1 and 2, the reduction (indicated as Red in the tables) of the content of most of the contaminants ranged from 75 to 98%. In most cases, the treated water, as such, can be used as a hydraulic fracturing fluid without additional treatment, or it can be used as an incoming stream, which can be subjected to additional processing (if necessary) for disposal into the environment. Removing high levels of contaminants, such as Ca, Mg, Na, Fe, Cl, Mn, TDS, CaClO ₃ , SO ₄ , Ва, hydrocarbons and biological pollution, which is achieved using the proposed method, it is highly desirable when treating large quantities of produced water, contaminated with waste streams generated during oilfield applications. In addition, this method advantageously and significantly prevents the release in the form of gas of harmful regulated volatile compounds, for example, hydrogen sulfide.

[00135] Although a preferred application of the method and system disclosed herein relates to applications associated with oil fields, for example, oil wells, subterranean formations, as well as technical and production water, additional industrial applications, in particular, include cooling water systems , water for enrichment of industrial minerals, geothermal wells, digesters, washers, bleaching plants, mass pools, white water systems, black alkali evaporators in the pulp industry, continuous casting processes in the metallurgical industry, air conditioning and cooling systems, clarification and recycled water systems, water treatment systems, membrane filtration systems, process flows in the processing of food products (meat, vegetables, sugar cane, poultry, fruits and soybeans); and waste treatment systems, as well as sumps, municipal wastewater treatment, municipal water supply systems, drinking water supply systems, aquifers and water tanks. In addition, in the context of this description, as a fluid processed by the method and system described herein, water volume, wastewater stream, wastewater, aqueous fluid volume and aqueous fluid stream are considered.

[00136] Various embodiments and modifications of the present invention have been described above. Such embodiments and modifications are merely illustrative; they do not in any way limit the scope of the invention as defined by the following claims. In addition, other variations of what has been described herein are also included within the scope of the invention. This invention can be modified and implemented in different, but equivalent ways, obvious to a person skilled in the art using the principles of this invention. In addition, with respect to the structural or device details described herein, no restrictions are intended other than the limitations described in the following claims. All numbers and ranges disclosed above may vary slightly. In addition, the terms used in the claims have their usual meaning, unless they are unambiguously and clearly defined differently. An invention incorporated by reference should not be construed as an alternative to any limitations of the invention, unless expressly stated otherwise.

Claims (41)

1. A method of reducing, inactivating, destroying, removing or eliminating pollution from an aqueous fluid selected from the group consisting of calcium, magnesium, sodium, iron, chloride, manganese, calcium chlorate, sulfate, barium, hydrocarbons, total dissolved solids substances, biological pollution and their combinations, and the method includes: i) introducing into the aqueous fluid an oxidizing agent selected from the group consisting of oxygen, air, oxygen-enriched air and combinations thereof, and introducing into the fluid a first chlorine oxide selected from the group consisting of chlorine dioxide, chlorite and combinations thereof , and ii) introducing a second chlorine oxide into the aqueous fluid after introducing the oxidizing agent and the first chlorine oxide, said second chlorine oxide containing chlorine dioxide, chlorite, or a combination thereof. 2. The method according to p. 1, in which the oxidizing agent is introduced at a rate that prevents the release of hydrogen sulfide or other volatile reducing agents in the form of gas. 3. The method according to any one of paragraphs. 1, 2, in which the oxidizing agent is introduced by venting through a venturi. 4. The method according to any one of paragraphs. 1, 2, in which the first chlorine oxide contains chlorite and is introduced into the aqueous fluid before or essentially simultaneously with the introduction of the oxidizing agent. 5. The method according to any one of paragraphs. 1, 2, in which an oxidizing agent is added to obtain a total dosage in the range of from about 20 mg / kg to about 2000 mg / kg in an aqueous fluid. 6. The method according to any one of paragraphs. 1, 2, further comprising introducing sodium hydroxide before or simultaneously with the first chlorine oxide to increase the pH to about 7-10. 7. The method according to any one of paragraphs. 1, 2, in which the first chlorine oxide contains chlorite. 8. The method according to p. 7, in which chlorite is added to obtain a dosage in the range from about 10 mg / l to about 500 mg / l in an aqueous fluid. 9. The method of claim 7, wherein the chlorite is a sodium chlorite solution. 10. The method according to any one of paragraphs. 1, 2, 8, 9, in which the second chlorine oxide contains chlorine dioxide. 11. The method according to p. 10, in which the second chlorine oxide is added with a dosage sufficient to obtain a residual content of chlorine dioxide in the aqueous fluid. 12. The method of claim 11, further comprising measuring and maintaining after processing the residual chlorine dioxide content in the aqueous fluid of at least about 0.1 mg / L. 13. The method according to p. 11, in which chlorine dioxide is administered to obtain a dosage in an aqueous fluid of from about 10 mg / L to about 50 mg / L. 14. The method according to any one of paragraphs. 1, 2, 8, 9, 11-13, in which before processing according to the method, the consumption of an oxidizing agent of contaminants in an aqueous fluid is from 30 mg / l to 5000 mg / l 15. The method according to any one of paragraphs. 1, 2, 8, 9, 11-13, wherein the step of introducing the oxidizing agent and the first chlorine oxide reduces the consumption of the aqueous fluid by at least 70-80% compared to the initial consumption of the aqueous fluid related to the pretreatment. 16. The method according to any one of paragraphs. 1, 2, 8, 9, 11-13, in which the source of the aqueous fluid is selected from the group including a tank, tank, pit, settling basin or reservoir for storing drainage water; water treatment plant; fracturing tank; or part of the equipment, pipeline or tank used for fracturing or oil production. 17. A method of processing an aqueous system, including: ensuring the availability of a water volume having an initial consumption of an oxidizing agent; introducing an oxidizing agent containing oxygen, air, oxygen-enriched air, or a combination thereof, into the water volume with a flow rate preventing the release of volatile reducing agents in the form of gas from the water volume; introducing sodium chlorite into the water; combining the water volume, the oxidizing agent and sodium chlorite, thereby reducing the initial consumption of the oxidizing agent to a reduced consumption of the oxidizing agent; introducing a separate portion of chlorine dioxide into the water volume in an amount sufficient to eliminate the reduced oxidizing agent consumption and to provide a residual chlorine dioxide content in the water volume of at least about 0.1 mg / L. 18. The fluid processing system, configured to perform the method according to any one of paragraphs. 1-17. 19. A fluid processing system for continuous use at a location of a hydrocarbon production well, comprising: at least one first processing section, at least one second processing section and at least one third processing section; at least one first fluid conduit for flowing a wastewater stream with an initial consumption of an oxidizing agent into said at least one first treatment section having at least one outlet that is in fluid communication with it; at least one second fluid conduit for circulating wastewater from said at least one first treatment section having at least one outlet and at least one inlet in communication therewith with the possibility of fluid transfer ; at least one first eductor in fluid communication with said at least one second fluid conduit and at least one oxidizing source and for introducing at least one oxidizing agent into said at least one second fluid piping in controlled quantities and with controlled flow; at least one second eductor in fluid communication with said at least one second fluid conduit and at least one chlorine oxide source and for introducing at least one first chlorine oxide into said at least at least one second fluid conduit in controlled amounts; at least one third fluid conduit for conveying wastewater from said at least one first treatment section to said at least one second treatment section, said at least one third fluid conduit being in communication with the possibility fluid transfer with at least one outlet of the at least one first processing section and with at least one inlet of the at least one second c processing section; at least one third eductor in fluid communication with said at least one third fluid conduit and at least one chlorine dioxide source and for introducing chlorine dioxide into said at least one third conduit for fluid in controlled quantities and with a controlled flow; wherein the first processing section comprises at least one removal device, at least one separator for removing contaminated sediments from said at least one first processing section, and has a residence time of from about 15 minutes to about 60 minutes; the specified second processing section contains at least one removal device, at least one outlet outlet of the lower drain, allowing the release into the specified at least one third processing section, and has a residence time of from about 10 minutes to about 30 minutes; and said third treatment section comprises at least one separator for removing precipitated contaminants from said at least one third treatment section and at least one outlet outlet of the upper discharge and has a residence time of from about 10 minutes to about 30 minutes. 20. The system according to p. 19, in which the first eductor and the second eductor are combined and configured to enter the specified at least one oxidizing agent before or simultaneously with the introduction of the specified at least one chlorine oxide. 21. The system of claim 20, wherein said oxidizing agent is selected from the group consisting of oxygen, air, oxygen enriched air, and combinations thereof. 22. The system according to any one of paragraphs. 19-21, wherein said at least one first chlorine oxide comprises an aqueous solution of sodium chlorite. 23. The system according to any one of paragraphs. 19-21, in which a controlled flow of oxidizing agent prevents the release of volatile reducing agents in the form of gas from wastewater. 24. The system according to any one of paragraphs. 19-21, in which the first, second and third eductors are a venturi.

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