Methods and systems for degrading compounds in a liquid stream

Abstract

A method and system for degrading compounds in a liquid stream is described; the method includes the steps of: providing a pump fluidly connected in series with a processing chamber having a mixer, and a reagent injector between the pump and the processing chamber; introducing the liquid flow into an inlet of the pump; operating the pump to direct a flow of liquid to the inlet of the process chamber to create a pressure from 0.1 bar to 10 bar between the pump inlet and the process chamber; introducing a degradation reagent into the flow through the injector at a pressure greater than or equal to the pressure between the pump inlet and the process chamber; and operating the mixer to mix the degradation agent in the liquid stream at a mixing strength in the range of from 0.7 W / L to 700 W / L to intentionally produce the physical and chemical conditions required to enhance the production of reactive species involved in the degradation process.

Description

TECHNICAL FIELD

[0001] The present invention relates to methods and systems for degrading compounds in a liquid stream. In particular, the present invention relates to treating a liquid stream to degrade unwanted compounds in the liquid stream. BACKGROUND

[0002] Ozone bubble reactors and venturi injection systems are the two main types of ozonation systems documented in the prior art. Ozone bubble reactors involve the injection of ozone gas into a liquid, creating bubbles that interact with the liquid. These bubbles transfer ozone into the liquid through diffusion. The efficiency of the ozone transfer depends on factors such as bubble size, contactor height, residence time, and the ozone concentration difference between the bubble and the liquid. However, these reactors tend to face severe limitations in terms of mass transfer efficiency, which leads to high capital and operating costs for ozone tower systems. In fact, larger bubbles rise rapidly to the surface, gradually reducing their pressure and reducing their contact time with the liquid. Furthermore, bubbles tend to coalesce and promote reactions only in their immediate vicinity, rather than throughout the entire liquid. Venturi injection systems are a technique that utilizes a tubular device specifically designed called a venturi. When a fluid passes through the narrow section of this tubular device, it accelerates, causing a pressure drop. During the venturi ozone injection process, ozone gas is introduced at the narrow section, and the pressure drop causes the gas to be drawn into the flowing liquid, resulting in ozone dissolution. The efficiency of the venturi injection is also quite limited and depends on factors such as the pressure differential, gas and liquid flow rates, and the geometry of the venturi. However, this system also has severe limitations. In fact, the maximum pressure differential generated by the device is limited by the absolute vacuum pressure. Furthermore, as the pressure decreases, the gas solubility decreases, further limiting the mass transfer efficiency. Additionally, the gas is typically released as relatively large bubbles, with sizes close to the venturi injector tip size. When introduced into a low-pressure environment, these bubbles tend to expand due to the lower pressure in the fluid caused by the venturi effect. These conditions severely limit the mass transfer and ozone reactivity. Furthermore, the flow rate limitations imposed by the venturi device due to the pressure head losses introduced by the system itself limit this technology to very low flow rates in major applications. Another type of solution available in the prior art is the use of a venturi injection system in a side stream configuration. However, this solution is severely limited in efficiency because most of the hydroxyl radicals are formed in the side stream, and since their lifetime is in the nanosecond range, it is very short, they cannot be transported in the fluid. Therefore, they are wasted in the side stream instead of being used to attack and degrade the pollutants in the main stream.

[0003] In the prior art, some devices for dosing and mixing reagents in a liquid stream are known. For example, the published international patent WO 2016 / 194009 describes a device configured in such a way that solid, liquid and gaseous reagents can be dosed upstream of the impeller of a circulation pump in various doses and combinations and, in particular, at a distance less than twice the diameter of the intake duct. Although it contributes to the dispersion of the reagents in the liquid stream to be treated in the impeller of the pump, the amount of injectable gaseous reagents is still very limited due to the gas blockage of the flow in the impeller (gas lock). Therefore, the device described in WO 2016 / 194009 generally requires the injection of more gaseous reagents downstream of the system to ensure the completion of the degradation reaction, thus also requiring additional contact time to complete the degradation of the target pollutants.

[0004] The published Italian patent application 102018000007374 describes a device for dosing reagents in a liquid stream comprising two pumps connected in series and a flange equipped with a device for dosing gaseous reagents in the liquid stream of a delivery duct connected to the first pump. The configuration of the hydraulic circuit allows the delivery of the first pump to be connected directly to this flange, which in turn is connected directly to the suction of the second pump. This device overcomes certain limitations highlighted in WO 2016 / 194009 using gaseous reagents, allowing a significant increase in the dose of gaseous reagents, ensuring a certain stability of the system. However, the disadvantage of this device is that it cannot complete the reaction before the liquid stream leaves the device. Therefore, additional contact time is required downstream of the device. In addition, the treatment time required to completely treat the pollutants cannot be controlled by increasing the concentration of gaseous reagents, due to the gas lock associated with the operation of the system at a fixed speed and a fixed volume, therefore a fixed mixing intensity. Furthermore, the possible unbalanced conditions that enhance the action of the related mass transfer are not recognized. Finally, this device focuses on the mass transfer in balanced conditions, without considering the yield of the degradation of the pollutants.

[0005] WO-A1-98 / 24728 discloses a method different from the method of the present application, which suggests maintaining the physical conditions set at the inlet, thus not recognizing the possibility of increasing the pressure at the inlet in the treatment device. Moreover, the intentional creation of unbalanced and unstable physical conditions in the system by increasing and decreasing the physical-chemical conditions of the process (e.g. pressure, velocity gradient and mixing intensity increase / decrease) in space and time is not recognized. These unbalanced and unstable physical conditions disclosed in the present application allow a significant increase in the mass transfer and treatment rate. Moreover, WO-A1-98 / 24728 discloses a solution limited in terms of pressure and mixing intensity, since the maximum applicable pressure in the treatment zone cannot exceed the pressure at the inlet, and the maximum mixing intensity in the same treatment zone cannot exceed the total pressure head available (i.e. the difference between the pressure at the inlet and the atmospheric pressure). Considering this limitation, WO-A1-98 / 24728 teaches maintaining the direction of the conditions established at the inlet, never considering the possibility of increasing the pressure and the mixing intensity, or optimally controlling their variation in order to intensify the pollutant degradation process.

[0006] WO-A2-2008052143 gives different teachings from the present application, disclosing the use of separate baffles between rotor and stator: these baffles are designed to keep the fluids separated for most of their residence time in the device, then to distribute the fluids uniformly and rapidly in a mixing zone. On the contrary, the present application maximizes the reaction and treatment volume, thus enabling and optimizing the mixing mechanism simultaneously to the reaction mechanism (instead of operating them in a separate and sequential way as in WO-A2-2008052143). Moreover, there is no mention of the need to control pressure or mixing intensity as independent variables, although they are relevant when referring to the overall goal of pollutants treatment by multiple degradation mechanisms (as disclosed in the present application). From a chemical point of view, WO-A2-2008052143 teaches something different from the present application, because the amount of hydrogen peroxide is limited. In fact, the maximum allowed concentration reported in WO-A2-2008052143 indicates an amount of 1 mg / L (1 ppm). On the contrary, for the applications disclosed in the present application, this amount represents a very low value. In fact, the present application discloses effective oxidation and reduction processes, which require the use of oxidizing and / or reducing substances almost always at concentrations greater than 1 mg / L (1 ppm). Finally, the purpose of WO-A2-2008052143 is not to achieve almost complete treatment with high reaction yield within the same disclosed device, but to achieve effective mixing between substances (not involving treatment). On the contrary, WO-A2-2008052143 discloses to deliver mixed fluids and substances in an upstream device (bioreactor), where the reaction function and treatment take place. In other words, in WO-A2-2008052143 the bio-chemical conversion occurs ex situ, contrary to the present application, where they occur in situ.

[0007] Despite the prior art, there is a need to further improve the dissolution of the degradation reagents and the degradation of the unwanted compounds in the liquid stream. SUMMARY

[0008] The present invention provides a method for degrading compounds in a liquid stream, the method comprising the steps of: providing a pump in series with a treatment chamber and fluidly connected at a fluid level, the treatment chamber comprising a mixer, and a reagent injector between the pump and the treatment chamber; introducing the liquid stream into an inlet of the pump; operating the pump to direct the liquid stream to an inlet of the treatment chamber to create a pressure increase between the pump inlet and the treatment chamber from 0.1 bar to 10 bar; introducing a degradation reagent into the liquid stream through the injector at a pressure greater than or equal to the pressure differential between the pump and the treatment chamber; and operating the mixer to mix the degradation reagent in the liquid stream at a mixing intensity from 0.7 W / L to 700 W / L (i.e. mixing power input per volume, where mixing power input is the power of the mixer and volume is the volume of the treatment chamber) to intentionally create the physical and chemical conditions required to simultaneously enhance mass transfer and degradation of one or more contaminants present in the liquid stream.

[0009] The method provides a high mass transfer efficiency of gaseous degradation reagents into the liquid stream. Furthermore, for gaseous degradation reagents, the system can be operated at high gas partial pressures as the gaseous stream can be injected directly into the liquid, the gaseous stream being characterized by a high concentration of gaseous reagent at high pressure. Thus, the effective dose (concentration-time product, CT value) of degradation reagent required is lower while providing improved reaction efficiency to efficiently remove a variety of different chemical compounds in the liquid stream by optimizing either the oxidation pathway, the reduction pathway, or a combination of both.

[0010] It has been found that the control of the mixing intensity is of utmost importance to obtain optimal dissolution of the degradation reagent, in particular gaseous degradation reagents, in the liquid stream. The mixer not only mixes the degradation reagent but also the reaction products, thus ensuring that the reaction is not hindered by diffusion limitations of the reaction products. Furthermore, higher mixing intensities favor the formation of highly reactive species, thus allowing the method to work under kinetic control conditions rather than mass transfer limited conditions. This is because the formation of such highly reactive oxidative and reductive species is a result of the reaction and decomposition mechanisms associated with the free radical chemistry of the dissolved degradation reagent used in the method. The mass injection rate of the degradation reagent into the liquid stream is also an important factor as it determines, together with the liquid flow rate, the maximum theoretical solubility concentration that can be reached by the method (obtained by dividing the mass injection rate by the liquid flow rate). The further synergistic effect of accelerating the chemical reactions and producing secondary reactive species (defined by the present invention as oxidative and reductive secondary reagents capable of degrading contaminants present in the fluid stream, said contaminants being formed upon injection of one or more primary reagents into a treatment chamber operated at a mixing intensity > 0.7 W / L and a pressure > 0.1 bar above atmospheric pressure) is achieved by controlling the centrifugal mixing speed in view of the pressure in the treatment chamber; controlling the degradation reagent mass injection rate in view of the residence time in the treatment chamber; and controlling the residence time in view of the pressure in the treatment chamber.

[0011] Furthermore, when using a combination of degrading reagents that react with each other (e.g. ozone and hydrogen peroxide), the control of the mixing intensity is also of major importance to establish a high reaction efficiency. The mass injection rate of the degrading reagents into the liquid stream is also an important factor. While the residence time is not an important factor per se, it becomes very important if considered in combination with the mixing intensity and the mass injection rate.

[0012] The method described in the present invention can be used to degrade unwanted chemical or biological compounds (i.e. pollutants). The degradation can be performed in a primary liquid stream or in a secondary side stream or in situ formed secondary species that are able to degrade the unwanted compounds in the primary liquid stream when injected into the primary liquid stream. The liquid stream can be aqueous or non-aqueous. The liquid stream can be a primary liquid stream or a secondary liquid stream. In a treatment system, the method can be applied to one or more liquid streams. Of particular interest are water streams, whether or not containing particulate matter. Some examples of liquid streams that can be treated in the method are ground water, rain water, runoff water, surface water, brackish water, sea water, diluted slurries, drinking water, municipal waste water, industrial waste water and process water (e.g. industrial water used in a production process), etc.

[0013] The method utilizes a pressurization zone in series with a high intensity mixing zone and connected at the fluid level, wherein the degrading reagent injection zone is located between the pressurization zone and the mixing zone. The fluid transport device can comprise a pump or any other device that is able to move the liquid stream under pressure. Some examples of fluid transport devices are linear mixers, rotary mixers, agitators, paddle mixers and pump flow mixers. In some embodiments, the fluid transport device comprises an impeller, e.g. a powered rotary impeller. The impeller can be rotated in a direction that increases or decreases the pressure provided by the pressurization zone, provided that the resulting pressure is still higher than the fluid pressure before entering the process described in the present invention. For example, if the pressure increasing zone increases the liquid pressure by 1 bar, the high intensity mixing zone can decrease the pressure by 0.1 bar, so that the liquid is still operated at a pressure that is higher than the pressure it had before entering the process. The mixing zone is formed in a treatment chamber. The liquid stream in the mixing zone is mixed with a mixer, e.g. a pump or any other mixing device. The treatment chamber can thus comprise the internal volume of the mixer itself. In some embodiments, the mixer comprises a centrifugal mixer. In some embodiments, the mixer comprises an impeller, e.g. a powered rotary impeller. In certain embodiments, both the fluid transport device and the mixer are pumps. The fluid transport device and the mixer can be the same type of device or different types of devices.

[0014] In this method, the mixing intensity, for example centrifugal mixing intensity, in the mixing zone is controlled to help optimize the mass transfer of the degrading reagent into the liquid stream and thus the extent of degradation of the compound. Further, in the case of using two or more degrading reagents that react with each other, controlling the mixing intensity helps to establish a higher reaction efficiency between the two reagents.

[0015] The mixing intensity is controlled in the range of 0.7 W / L to 700 W / L. In some embodiments, the mixing intensity is in the range of 50 W / L to 500 W / L. In some embodiments, the mixing intensity is in the range of 60 W / L to 360 W / L. In some embodiments, the mixing intensity is in the range of 120 W / L to 300 W / L. The mixing intensity is the mixing power input per unit volume. The mixing power is directly related to the operating speed of the mixer. Thus, to obtain the desired mixing intensity, the speed of the mixer, for example centrifugal mixer, is controlled in the range of 500 rpm to 9500 rpm. In some embodiments, the speed is controlled in the range of 1000 rpm to 5000 rpm. In some embodiments, the speed is controlled in the range of from 1200 rpm to 3600 rpm (i.e., 20-60 Hz). In some embodiments, the speed is 1800 rpm (i.e., 30 Hz) or higher. In some embodiments, the speed is in the range of 2400 rpm to 3300 rpm (i.e., 40-55 Hz). Depending on the scale of the processing system, the volume of the processing chamber can be in the range of 2 L to 20000 L. The method can be configured to have an overall architecture comprising modular processing methods connected in parallel and / or in series to provide the required flow rate and achieve the required performance.

[0016] In this method, the pressure between the pressurization zone and the mixing zone, including the pressure in the processing chamber, is controlled to help optimize the mass transfer of the degrading reagent into the liquid stream. Thus, the pressure is maintained in the range of 0.1 bar to 10 bar. In some embodiments, the pressure is maintained in the range of 1 bar to 10 bar. In some embodiments, the pressure is maintained in the range of 1 bar to 5 bar. In some embodiments, the pressure is maintained in the range of 1.25 bar to 4 bar. In some embodiments, the pressure is maintained in the range of 1.5 bar to 4 bar. In some embodiments, the pressure is maintained in the range of 1.25 bar to 3 bar. In some embodiments, the pressure is maintained in the range of 1.6 bar to 3 bar. The pressure can be maintained by operation of the fluid delivery device and / or by utilizing a valve. The valve can be a simple valve or a back pressure regulator. The valve can be operated manually or automatically in response to changing pressure. In some embodiments, the valve is downstream of the mixing zone.

[0017] In the method, the residence time of the fluid stream between the pressurization zone and the outlet of the mixing zone can also be controlled to optimize the dissolution of the degradation reagent in the fluid stream. The residence time can also be controlled to optimize the production of secondary oxidizing and reducing species involved in the treatment. Furthermore, when two or more degradation reagents that react with each other are used, controlling the residence time also helps to establish a high reaction efficiency between the two reagents. In some embodiments, the fluid stream has a residence time between the pressurization zone and the outlet of the treatment chamber of 0.1 seconds to 100 seconds. In some embodiments, the residence time is in the range of 0.1 seconds to 60 seconds. In some embodiments, the residence time is in the range of 0.1 seconds to 40 seconds. In some embodiments, the residence time is in the range of 1 second to 36 seconds.

[0018] A degradation reagent is a chemical that is introduced into the fluid stream that results in the degradation of an unwanted compound in the fluid stream. The degradation can occur through direct or indirect reaction mechanisms. Such mechanisms can be in situ active (i.e., in the main fluid stream) or non-in situ (e.g., in a second fluid stream). In the latter case, the second fluid stream is injected into the first fluid stream as a degradation reagent to degrade the unwanted compound present in the fluid stream. The unwanted compound can also be a plurality of unwanted compounds (or contaminants) or a physical-chemical property of the fluid (e.g., total organic carbon, hardness, salinity, light transmittance, etc.). The type of degradation mechanism used can depend on the compound to be degraded or the physical-chemical property to be modified by the process. The degradation mechanism is typically of an oxidizing or reducing nature. The degradation reagent can be introduced into the fluid stream in any suitable physical form, including gases, liquids, and solids. Gases and liquids are typically the easiest to introduce into a liquid stream, such that the degradation reagent is transferred to the fluid stream at a higher mass than solids. Liquid degradation reagents can be pure liquids or solutions. Some examples of degradation reagents include ozone (O3), chlorine (Cl2), chlorine dioxide (CIO2), hydrogen peroxide (H2O2), hypochlorite (HCIO - ), potassium permanganate (KMnO4), ferric chloride (FeCl3), potassium dichromate (K2Cr2O7), nitric acid (HNO3), potassium iodate (KIO3), potassium persulfate (K2S2O8), chloramine (pre-formed or in situ), peracids (e.g., peracetic acid, performic acid), sodium sulfite (Na2SO3), sodium bisulfite (NaHSO3), sodium borohydride (NaBH4), ascorbic acid (vitamin C), ferrous sulfate (FeSO4), sodium dithionite (Na2S2O4), hydroquinone (C6H6O2), sodium formate (HCOONa), sodium dithionite (Na2S2O4), sodium amalgam (NaHg), ionic liquids, hydrogen, oxygen, nitrogen, argon, activated carbon, zeolites, resins, polymers (e.g., geopolymer), coagulants, sludge, biochar, synthetic absorbents, natural absorbents, clays, etc. In some embodiments, more than one degradation reagent can be used in the method.

[0019] The degradation reagent can be injected into the liquid stream at various injection zones in the liquid flow path. However, in this approach, at least one injection zone is in the pressure increase zone (i.e., the location of the fluid transport device) and the mixing zone. The mass injection rate of the degradation reagent is an important factor to increase the mass transfer efficiency of the degradation reagent into the liquid stream to ultimately optimize the effective degradation of the compound. Furthermore, in the case of using two or more degradation reagents that react with each other, controlling the mass injection rate helps to establish a high reaction efficiency between the two reagents. Therefore, for liquid stream flow rates in the range of 1-10 m 3 / hr, the mass injection rate, particularly at the injection zone between the pressure increase zone and the mixing zone, is preferably in the range of 30-200 g / hr or 45-160 g / hr, for example, 54-120 g / hr. The mass injection rate is directly proportional to the liquid stream flow rate.

[0020] In some embodiments, the mass injection rate provides a concentration-time product (CT value) dose in the range of 0-2000 mg / L min. For strong oxidants (e.g., ozone, chlorine, formic acid, etc.), the CT value can be in the range of 0.1 mg / L min to 10 mg / L min, particularly 0.1 mg / L min to 5 mg / L min, for example, 0.1 mg / L min to 1 mg / L min. For weak oxidants (e.g., chloramines, peracetic acid, etc.), the CT value ranges from 0.1 mg / L min to 100 mg / L min. For free radicals, the CT value can be in the range of less than 0.1 mg / L min. For absorbents or ion resins, the CT value can be in the range of 0.1 mg / L min to 2000 mg / L min. For other oxygen-containing and non-oxygen-containing reactive species, the CT value can be in the range of 0.1 mg / L min to 1 mg / L min. The introduction of the degradation reagent into the liquid stream can be by use of a syringe, preferably a high pressure syringe (e.g., a high pressure needle syringe), which can inject the degradation reagent into the liquid stream at a pressure that meets or exceeds the pressure in the treatment chamber. Some suitable syringes include, for example, L-shaped syringes, microchannel syringes, needle syringes, nanobubble syringes, microreactor syringes, U-shaped syringes, Venturi syringes, fixed-throat syringes, and adjustable-throat syringes. In some process configurations, the syringe can be used as a side stream device to generate a secondary oxidizing or reducing species to be introduced into the primary liquid stream. In addition to the injection zone between the pressure increase zone and the mixing zone, the method can include one or more other injection zones. The one or more other injection zones can also be between the pressure increase zone and the mixing zone, upstream of the pressure increase zone, or downstream of the mixing zone.

[0021] Higher partial pressure of gaseous reagents or higher concentrations of degrading reagents in the injectable material are suitable for effective degradation of compounds. Concentrations depend on the nature of the degrading reagent and the physical conditions of the injection. Higher pressures are more preferred because they increase the partial pressure of gaseous reagents and the solubility of other reagents. Generally, concentrations of 5 wt% or more are more preferred, with higher concentrations resulting in faster and more effective degradation. Shorter residence times between the exit point of the degrading reagent and the liquid injection point are more desirable because they minimize reagent loss due to parasitic self-degradation reactions. In some embodiments, the concentration of the degrading reagent in the injectable material is 10 wt% or more. In some embodiments, the concentration of the degrading reagent in the injectable material is in the range of 5-50 wt%. In some embodiments, the concentration of the degrading reagent in the injectable material is in the range of 10-50 wt%. In some embodiments, the concentration of the degrading reagent in the injectable material is in the range of 10-20 wt%.

[0022] When more than one degrading reagent is used in the method, one or more of the degrading reagents is introduced into the liquid stream between the pressurization zone and the mixing zone. Other degrading reagents can be introduced into the liquid stream upstream of the pressurization zone, for example, before the inlet of the pump used to introduce the liquid stream into the pressurization zone. Other degrading reagents can be introduced into the liquid stream downstream of the mixing zone. Two or more of the degrading reagents can be reactive with each other, undergoing a reaction to produce another reactive species that can be used to degrade certain compounds. In some embodiments, hydrogen peroxide is with another degrading reagent (e.g., ozone) such that the reaction between the hydrogen peroxide and the other degrading reagent produces hydroxyl ions, which are effective at degrading certain compounds. In some embodiments, hydrogen peroxide is with another degrading reagent (e.g., ozone), the degrading reagent being introduced into the liquid stream in an amount that has a molar ratio to the hydrogen peroxide of 0.1 : 1 to 10: 1, for example, 1.7: 1 to 2: 1.

[0023] In some embodiments, the method includes one or more other modes of treatment of the liquid stream, such as exposure to vacuum ultraviolet (VUV) light, exposure to ultraviolet (UV) light, exposure to visible (Vis) light, exposure to infrared (IR) light, sonication, ultrasonication, immersion, blending, milling, pressurized compression, decompression, expansion, pulverization, filtration, biofiltration, membrane filtration, photocatalysis, ultrasound, electrocoagulation, electrolysis, advanced reduction processes, sedimentation, digestion, fermentation, etc. One or more of the other modes of treatment can be used upstream of the pressurization zone, downstream of the mixing zone, between the pressurization zone and the mixing zone, or some combination thereof.

[0024] The compounds to be degraded are considered to be contaminants in the liquid stream. The liquid stream can contain a variety of compounds. Some classes of chemical compounds include, for example, biological compounds (e.g., microbial communities, microorganisms, proteins (e.g., enzymes), polynucleotides (e.g., DNA, RNA), lipids), pharmaceuticals (e.g., antibiotics), personal care products, olefins, endocrine disruptors (e.g., hormones), pesticides, petroleum hydrocarbons, halogenated organic compounds (e.g., fluorinated compounds (e.g., polyfluoroalkyl substances (PFAS) compounds) and chlorinated compounds (e.g., polychlorinated biphenyls (PCBs)), nitroaromatics, flame retardants, organic compounds in industrial wastewater (e.g., phenolic compounds, polycyclic aromatic hydrocarbons (PAHs), dioxins, and furan compounds), and heavy metals. Some specific examples of compounds to be degraded in a liquid stream are: trihalomethane, 4-chlorobenzoic acid, perfluorohexanoic acid, perfluorooctanoic acid, caffeine, acetaminophen, ciprofloxacin, carbamazepine, and sulfamethoxazole. The method can also be configured to control the production of disinfection byproducts, for example, by adding hydrogen peroxide prior to gaseous ozone, thereby preventing the formation of bromate. Similarly, the formation of dichloramine can be prevented by controlling the pH with an acid or a base and by using a stoichiometric ratio of treatment reagents. The method can also be configured to allow the in situ formation of hydroxyl radicals via advanced oxidation processes, hydrated electrons via advanced reduction processes, or disinfectants and metal hydroxides via combined oxidation-reduction processes (e.g., simultaneous addition of sodium hypochlorite and aluminum chloride to form chlorine gas and aluminum hydroxide).

[0025] In the present invention, the degradation reagents are injected into the liquid stream in a confined pressurized volume and in the presence of high intensity mixing. In this case, unexpected physicochemical behaviors occur. These physicochemical behaviors are used to optimize the injection and reaction of the degradation reagents in the fluid treatment process and system. Unlike other methods and systems, the method described herein operates by promoting non-uniform conditions, particularly pressure conditions, throughout the liquid stream, thereby driving the reagents away from equilibrium. Under these non-uniform (turbulent) conditions, diffusion, solubility, hydrodynamics, turbulence, and surface tension never reach equilibrium. Since it is known that reaching equilibrium conditions results in a limitation of mass transfer and reactivity in physicochemical systems, avoiding equilibrium conditions accelerates the diffusion (mass transfer) and reaction rate (reactivity) of the degradation reagents in the liquid stream, thereby allowing for shorter residence times of the liquid stream in the mixing zone, resulting in lower CT value doses and higher degradation efficiency in smaller footprints of the system.

[0026] By combining high-pressure conditions with appropriate high-intensity hybrid dynamics to generate a non-uniform pressure gradient throughout the liquid flow in the mixing zone, as described by the principle of surface tension, the dispersion and recombination of degradable materials into nanocavities also play a crucial role. Particularly when the degrading agent is a gas, surface tension tends to minimize the surface area of ​​gaseous nanobubbles, leading to nanobubble contraction and implosion. Furthermore, pressure differentials and gas expansion can cause nanobubbles to expand and potentially explode. These physical phenomena influenced by the principle of surface tension contribute to nanobubble formation and affect the reactivity of gases (e.g., ozone) within the liquid flow. By controlling pressure and mixing, turbulence is controlled, enabling efficient diffusion and dissolution of the degrading agent within the liquid flow. The recombination of the degrading agent into nanocavities (e.g., gaseous nanobubbles) enhances reactivity; these physical processes collectively improve the performance and effectiveness of the process.

[0027] Furthermore, under the heterogeneous conditions provided in this method, the combination of various degradation reagents interacts synergistically to further enhance degradation efficiency. For example, ozone and sodium hypochlorite can generate in-situ reactive oxygen species and free radicals. The ozonation-chlorination process produces highly reactive intermediates such as hydroxyl radicals (OH·) and chlorine radicals (Cl·). These free radicals are strong oxidants and can participate in further reactions. Compared to using ozone or sodium hypochlorite alone, the combination of ozone and sodium hypochlorite can synergistically enhance oxidation and disinfection capabilities. The generated active species can effectively degrade organic pollutants, eliminate microorganisms, and remove odors. Similarly, if persulfate reagents are used instead of oxidants, sulfur radicals can be formed. Sulfur radicals are particularly useful in generating hydrated electrons, thus promoting advanced reduction processes.

[0028] The present invention also provides a system for degrading compounds in a liquid stream, as described below.

[0029] In the course of the following detailed description, other features will be described or will become apparent. It should be understood that each feature described herein can be used in any combination with any one or more other described features, and each feature does not necessarily depend on the presence of another feature unless it is obvious to those skilled in the art. Attached Figure Description

[0030] To make the understanding clearer, preferred embodiments will now be described in detail by way of example with reference to the accompanying drawings, wherein: Figure 1 A schematic diagram of an implementation scheme for a system used to carry out a process for degrading compounds in a liquid stream is depicted.

[0031] Figure 2 A schematic diagram depicts another embodiment of a system for carrying out a process of degrading compounds in a liquid stream.

[0032] Figure 3 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0033] Figure 4 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0034] Figure 5 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0035] Figure 6 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0036] Figure 7 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0037] Figure 8 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0038] Figure 9 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0039] Figure 10 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0040] Figure 11 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0041] Figure 12 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0042] Figure 13 A schematic diagram depicting another embodiment of a system for conducting a process of degrading compounds in a liquid stream.

[0043] Figure 14A A top view of an example of a system for conducting a process of degrading compounds in a liquid stream.

[0044] Figure 14B A side view of Figure 14A is depicted.

[0045] Figure 14C A view perpendicular to Figure 14B is depicted. Figure 14Aside view.

[0046] Figure 15A depicts the 3D surface plot of the measured dissolved ozone (mg / L), pressure (bar) and impeller speed (Hz) in the treatment chamber of the system of Figure 14A to determine the optimal pressure and impeller speed for the mass transfer of ozone into the water stream during the operation of the system.

[0047] Figure 15B depicts the 3D surface plot of the measured dissolved ozone (mg / L), pressure (bar) and residence time (s) of ozone in the treatment chamber of the system of Figure 14A to show the interdependence and optimality of the ozone mass transfer in the treatment chamber.

[0048] Figure 16A depicts the 3D surface plot of the impeller speed (Hz) and residence time (s) of ozone in the treatment chamber of the system of Figure 14A versus the molar ratio of reacted ozone to reacted hydrogen peroxide to show the interdependence and optimal value of the molar ratio of reacted ozone to reacted hydrogen peroxide.

[0049] Figure 16B depicts the 3D surface plot of the impeller speed (Hz) and the injected ozone mass rate (g / hr) in the treatment chamber of the system of Figure 14A versus the molar ratio of reacted ozone to reacted hydrogen peroxide to show the interdependence and optimal value of the molar ratio of reacted ozone to reacted hydrogen peroxide.

[0050] Figure 17 depicts the 3D surface plot of the injected ozone mass rate (g / hr) versus the impeller speed (Hz) in the process for degrading 4-chlorobenzoic acid (PCBA), where all other factors remain constant and equal to their average values.

[0051] Figure 18A depicts the plot of the caffeine concentration (c) in the water stream after treatment with ozone versus the impeller speed (Hz) in the process for degrading caffeine, where all other factors remain constant and equal to their average values.

[0052] Figure 18B depicts the plot of the caffeine concentration (c) in the water stream after treatment with ozone versus the ozone mass rate (g / hr) in the process for degrading caffeine, where all other factors remain constant and equal to their average values.

[0053] Figure 19A plot depicting perfluorooctanoic acid (PFOA) concentration (pg / L) in the effluent stream after treatment with ozone in a method for degrading PFOA versus the concentration-time (CT value) dose of ozone (mg / L), where all other factors were held constant and equal to their average values.

[0054] Figure 20 A 3D surface plot depicting absorbance at 254 nm (1 / m) in the effluent stream after treatment with ozone and sodium hypochlorite versus the concentration-time (CT value) dose of ozone (O3) (mg / L) and the concentration-time (CT value) dose of hydrogen peroxide (mg / L), where all other factors were held constant and equal to their average values.

[0055] Figure 21 A 3D surface plot depicting chemical oxygen demand (COD) (pg / L) in the effluent stream after treatment with ozone and sodium hypochlorite versus the concentration-time (CT value) dose of ozone (O3) (mg / L) and the concentration-time (CT value) dose of hydrogen peroxide (mg / L), where all other factors were held constant and equal to their average values.

[0056] Figure 22 A 3D surface plot depicting the sum of micropollutants (mg / L) in the effluent stream after treatment with ozone and sodium hypochlorite versus the concentration-time (CT) dose of ozone (O3) (mg / L) and the concentration-time (CT) dose of hydrogen peroxide (mg / L), where all other factors were held constant and equal to their average values. DETAILED DESCRIPTION

[0057] Figures 1 to 13 is a schematic of thirteen embodiments of a system for performing a process of degrading a compound in a liquid stream.

[0058] Figure 1A system 10 for degrading compounds in a fluid stream is described. A fluid stream 18 containing compounds flows into the system 10 through an inlet 14. The inlet 14 is in fluid communication with a pressurization zone 11 in which a fluid delivery device 16 (e.g., a pump or other device with an impeller) propels the fluid stream 18 under pressure into a treatment chamber including a mixing zone 12. The system 10 also includes a plurality of degradation reagent injection zones 13 having injectors for injecting degradation reagents into the fluid stream. In the system 10, the fluid stream 18 from the pressurization zone 11 enters a first degradation reagent injection zone 13a in which a first degradation reagent A is injected into the fluid stream 18, then enters a second degradation reagent injection zone 13b in which a second degradation reagent B is injected into the fluid stream 18. The fluid stream 18 containing the degradation reagents A and B enters the mixing zone 12 in which the degradation reagents A and B are mixed by a centrifugal mixer 17 (e.g., an impeller). The treated fluid from the treatment chamber exits the mixing zone 12 as a treated fluid stream 19 through an outlet 15. The pressure in the treatment chamber can be controlled by operation of the fluid delivery device 16.

[0059] Figure 2 Another embodiment is described in which a system 20 includes the elements 11, 12, 13, 14, 15, 16, 17, 18, and 19 of the system 10 except that the path length of the treatment chamber is lengthened by inserting an extension chamber 21 (e.g., a length of pipe or tubing) between the first degradation reagent injection zone 13a and the second degradation reagent injection zone 13b. In addition, the fluid delivery device 16 includes a pump having an impeller that co-rotates with the centrifugal mixer 17 in a direction of rotation X. This arrangement provides a longer residence time for the fluid stream 18 in the treatment chamber.

[0060] Figure 3 Another embodiment is described in which a system 30 includes the elements 11, 12, 13, 14, 15, 16, 17, 18, 19, and 21 of the system 20 except that the fluid delivery device 16 has an impeller that counter-rotates with the centrifugal mixer 17, e.g., the impeller rotates in a direction of rotation X while the centrifugal mixer 17 rotates in a direction of rotation Y. This arrangement provides a different mixing mechanism for the fluid stream 18 in the treatment chamber.

[0061] Figure 4 Another embodiment is described in which a system 40 includes the elements 11, 12, 13, 14, 15, 16, 17, 18, and 19 of the system 10 except that the first degradation reagent injection zone 13a is located upstream of the inlet 14. This arrangement provides a longer residence time for the first degradation reagent A in the fluid stream 18 without increasing the residence time of the fluid stream 18 in the treatment chamber.

[0062] Figure 5Another embodiment is described in which system 50 includes elements 11, 12, 13, 14, 15, 16, 17, 18, and 19 of system 40, except that first degradation reagent injection zone 13a includes two ports for simultaneous injection of first degradation reagent A and third degradation reagent C. Likewise, second degradation reagent injection zone 13B includes two ports for simultaneous injection of second degradation reagent B and fourth degradation reagent D. This arrangement allows for the injection of more than two degradation reagents into stream 18.

[0063] Figure 6 Another embodiment is described in which system 60 includes elements 11, 12, 13, 14, 15, 16, 17, 18, 19, and 21 of system 20, except that multiple degradation reagent injection zones 13 include a third degradation reagent injection zone 13c upstream of inlet 14 and a fourth degradation reagent injection zone 13d downstream of outlet 15. Third degradation reagent C is injected into stream 18 in third degradation reagent injection zone 13c. Fourth degradation reagent D is injected into treated stream 19 in fourth degradation reagent injection zone 13d. Such an arrangement allows for the injection of degradation reagents into treated stream 19 for further treatment of the stream.

[0064] Figure 7 Another embodiment is described in which system 70 includes elements 11, 12, 13, 14, 15, 16, 17, 18, and 19 of system 40, except that post-treatment chamber 71 is inserted downstream of outlet 15, and a fourth degradation reagent injection zone 13d is inserted between outlet 15 and post-treatment chamber 71 for injection of fourth degradation reagent D into the treated liquid exiting outlet 15. In addition, post-treatment chamber 71 has its own post-treatment outlet 75 downstream of it, and system 70 includes a fifth degradation reagent injection zone 13e downstream of post-treatment outlet 75 for injection of fifth degradation reagent E into system 70 as treated stream 19 exits system 70. This arrangement allows for further treatment of the stream downstream of mixing zone 12.

[0065] Figure 8 Another embodiment is described in which system 80 includes elements 11, 12, 13, 14, 15, 16, 17, 18, 19, 71, 75 of system 70, except that post-treatment chamber 71 is equipped with ultraviolet light 81 for further treatment of the liquid in post-treatment chamber 71. This arrangement allows for UV treatment of the liquid stream downstream of mixing zone 12.

[0066] Figure 9 Another embodiment is described in which system 90 includes elements 11, 12, 13, 14, 15, 16, 17, 18, 19, and 21 of system 60, except that said extension chamber 21 is equipped with ultraviolet light 91 for treatment of stream 18 in said extension chamber 21. This arrangement allows for UV treatment of stream 18 in the treatment chamber.

[0067] Figure 10 Another embodiment is described, in which system 100 includes elements 11, 12, 13, 14, 15, 16, 17, 18, 19, and 21 of system 90, except that the extension chamber 21 is equipped with a filtration unit for treating the liquid flow 18 in the extension chamber 21. This arrangement allows for the filtration of the liquid flow 18 in the treatment chamber.

[0068] Figure 11 Another embodiment is described, in which system 110 includes elements 11, 12, 13, 14, 15, 16, 17, 18, 19, and 21 of system 60, except that the fluid delivery device 16 is specifically a first pump 16a and the centrifugal mixer 17 is specifically a second pump 17a. Although the liquid flow 18 flows through the elements in the same order as in system 60, the structures of the elements are somewhat different from each other.

[0069] Figure 12 Another embodiment is described, in which system 120 includes elements 11, 12, 13, 14, 15, 16a, 17a, 18, and 19 of system 110, except that the extension chamber 21 has been removed, such that the first degradation reagent injection region 13a and the second degradation reagent injection region 13b are like... Figure 1 The systems in system 10 are adjacent to each other.

[0070] Figure 13 Another embodiment is described, in which system 130 includes elements 11, 12, 13, 14, 15, 16a, 17a, 18, and 19 of system 120, except that a pressure regulator 131 (e.g., a valve) is inserted between mixing zone 12 and outlet 15. The pressure regulator 131 can be operated to help maintain the desired pressure in the processing chamber.

[0071] Figure 14A , Figure 14B and Figure 14CAn example of a system 150 for degradation of compounds in a liquid stream is shown, in which a first high-speed centrifugal pump 146 is fluidly connected in series with a second high-speed centrifugal pump 147. The first pump 146 receives a liquid stream 118 to be treated through a first pump inlet 114 and pumps the liquid stream 118 through a first pump outlet 116 into a main injection zone 149 between the first pump 146 and the second pump 147. The liquid stream 118 pumped through the main injection zone 149 enters the second pump 147 through a second pump inlet 117 to be mixed in the second pump 147 with any degradation reagents introduced into the liquid stream 118 in the main injection zone 149. The treatment chamber includes the second pump 147 (i.e., the cavity in the second pump 147 and the second pump inlet 117). The treated liquid stream 119 is pumped out of the second pump 147 through a second pump outlet 115. The main injection zone 149 includes flanges 113a, 113b bolted together and mounted on the first pump outlet 116 and the second pump inlet 117. The flanges 113a, 113b have a central bore to allow the liquid stream 118 to flow therethrough. The flange 113a includes a plurality of injection ports 123a positioned annularly around the flange 113a, which are configured to allow injection of degradation reagents into the central bore, and thus into the liquid stream 118 flowing through the central bore. Likewise, the flange 113b includes a plurality of injection ports 123b annularly located around the flange 113b, which are configured to allow injection of degradation reagents into the central bore, and thus into the liquid stream 118 flowing therethrough. The injection ports 123a and 123b are preferably configured to allow injection of a gas (e.g., ozone, chlorine, etc.) into the liquid stream 118.

[0072] System 150 also includes a pre-injection zone 131 and a post-injection zone 136. Pre-injection zone 131 allows for injection of a degradation reagent into liquid stream 118 prior to its entry into first pump 146. Pre-injection zone 131 includes a pre-flange 113c mounted on first pump inlet 114 and system inlet 121. Pre-flange 113c has a central bore to allow liquid stream 118 to flow therethrough. Pre-flange 113c includes a plurality of injection ports 123c annularly positioned about pre-flange 113a that are configured to allow injection of a degradation reagent into the central bore, and thus into liquid stream 118 flowing therethrough. Post-injection zone 136 allows for injection of more degradation reagent into treated liquid stream 119 after it exits second pump 147. Post-injection zone 136 includes a post-flange 113d mounted on second pump outlet 115 and system outlet 122. Post-flange 113d has a central bore to allow treated liquid stream 119 to flow therethrough. Post-flange 113d includes a plurality of injection ports 123d annularly positioned about post-flange 113d that are configured to allow injection of more degradation reagent into the central bore, and thus into treated liquid stream 119 flowing therethrough. Injection ports 123c and 123d are preferably configured to allow injection of a liquid (e.g., hydrogen peroxide, hypochlorite solution, etc.) into the respective liquid stream.

[0073] System 150 also includes a pressure regulator 141 (e.g., a simple valve, an automatic back pressure regulator, etc.) in treated liquid stream 119 downstream of second pump 147, and in this embodiment downstream of post-injection zone 136. Pressure regulator 141 is operable to control the pressure in the treatment chamber.

[0074] Examples Materials and Methods Configuration of Spiked Solutions A specific contaminant solution was added to a 1000 gallon feed tank, which was a combination of the following ingredients, depending on the purpose of the treatment: methylene blue, 4-chlorobenzoic acid, pharmaceuticals, methanol for (providing / determining) organic carbon, and sodium nitrite. The feed tank was filled with dechlorinated water and used as is for Examples 1 and 2. For Example 3, the water was further spiked with contaminants to a final concentration of approximately 5 mg / L of methylene blue, 500 µg / L of 4-chlorobenzoic acid (pCBA), 150 µg / L of acetaminophen, 150 µg / L of caffeine, 50 µg / L of ciprofloxacin, 50 µg / L of carbamazepine, and 50 µg / L of sulfamethoxazole. A set of tests for Example 3 was modified by adding 5 mg / L of NaNO2 (as an ozone scavenger) and 10 mg / L of total organic carbon (TOC) (using methanol as a radical scavenger) in addition to the above contaminants to change the water quality. The operating procedure for the process tests can be summarized as follows: 1. Fill the inlet of the 1000 gallon feed tank with dechlorinated water.

[0075] 2. Add the contaminants to the desired concentration.

[0076] 3. Mix within the tank to ensure uniform feed characteristics.

[0077] 4. Run the pilot system with the prepared batch of water.

[0078] 5. Sample before and after the test system.

[0079] 6. Ozone residual test method Ozone residual was detected using a Chemetrics™ ozone vacuum bottle kit K-7423, with a Hach DR3900 spectrophotometer set to 515 nm. All reagents were purchased through Chemetrics™. Five drops of A-7400 activator solution were added to a sample cup, then 25 mL of sample was added to the cup. A vacuum ampoule was broken in the solution. The contents were mixed and the absorbance was read on the spectrophotometer. Ozone concentration was calculated using the absorbance method.

[0080] Nitrate and nitrite test method Nitrate and nitrite standards were purchased from Hach™ at concentrations of 822 ppm NO2 - and 44 ppm NO3 - . To make a calibration curve, six solutions of NO2 - and NO3 -Standards were run on a Metrohm™ 930 Compact IC Flex ion chromatography system. The column used was Metrosep™ A Supp 5 - 150 / 4.0. The eluent was prepared by mixing 0.32 M / 0.1 M sodium carbonate / sodium bicarbonate with 1 L RO water, with an eluent flow rate of 0.7 mL / min. The injection volume was 20 µL. - The retention time of the peak was 7.4 min. - The retention time of the peak was 10.5 min.

[0081] Total organic carbon test method Total organic carbon (TOC) testing was performed using a TOC LR Hach™ kit and following the Hach™ 10129 Low Range TOC method. The sample was heated according to the method using a Hach DRB 200 and the TOC was measured after the reaction had taken place using a Hach™ DR 900.

[0082] 4-Chlorobenzoic acid concentration test method 4-Chlorobenzoic acid (pCBA) testing was performed using an Agilent™ 1260 HPLC with a diode array detector (DAD). Immediately after the sample was removed from the test system, 1 mL of 200 ppm sodium thiosulfate was added to the 9 mL sample. The purpose of the sodium thiosulfate was to quench the sample by reacting with residual hydrogen peroxide and ozone to ensure that the pCBA concentration remained constant while waiting for HPLC analysis. The vial was mixed thoroughly and approximately 1 mL was filtered using a nylon filter into a labeled HPLC vial. Seven pCBA standards were made in reverse osmosis (RO) water ranging from 0.005 ppm to 0.5 ppm to make a calibration curve. The standards were run on an Agilent™ 1260 HPLC with a DAD detector. The column used was Agilent Zorbax™ SB-C18 4.6 x 250 mm; 5 µm, with a temperature of 25 °C. The mobile phase was an isothermal mixture of 52% 0.1% phosphoric acid in water and 48% acetonitrile, with a flow rate of 1.5 mL / min. The injection volume was 100 µL and the detector was set to 238 nm. The pCBA peak was identified at a retention time of 3.9 min, with a total run time of 6.5 min.

[0083] Drug concentration test method Drug testing was performed using an Agilent™ 1260 HPLC with triple quadrupole mass spectrometer detector (TQ). Immediately after removing the sample from the test system, 1 mL of 200 ppm sodium thiosulfate was added to the 9 mL sample. The purpose of the sodium thiosulfate was to quench the sample by reacting with residual hydrogen peroxide and ozone to ensure the drug concentration remained constant while waiting for HPLC analysis. The vial was mixed well and approximately 1 mL was filtered using a nylon filter into a labeled HPLC vial. To make a calibration curve, seven drug standards (containing caffeine, acetaminophen, ciprofloxacin, carbamazepine, sulfamethoxazole, and erythromycin) were prepared in RO water from 0.005 ppm to 0.5 ppm. The standards were run on an Agilent™ 1260 HPLC with TQ detector. The chromatographic column used was an Agilent Zorbax™ Eclipse C18 2.1 x 50 mm; 1.8 pm, with a temperature of 35 °C. The mobile phase was a gradient with A being 0.1% formic acid in water and B being acetonitrile, with a flow rate of 0.4 mL / min. The injection volume was 100 pL, with a total run time of 14 minutes. The following steps were employed: 1. Immediately after sampling, 9 mL of sample was removed into a 15 mL centrifuge tube.

[0084] 2. 1 mL of 200 ppm sodium thiosulfate was removed and placed into the centrifuge tube to quench the sample, inverted several times, and mixed well.

[0085] 3. Approximately 1 mL of sample was filtered using a nylon filter into a labeled HPLC vial.

[0086] 4. The sample was placed in the autosampler and the HPLC method was run.

[0087] 5. If the sample needed to be stored for later running, the sample was stored in the refrigerator.

[0088] 6. The drug concentration was determined from the peak area using the calibration curve.

[0089] 7. The dilution from the sodium thiosulfate must be taken into account.

[0090] Methylene blue concentration test method The methylene blue concentration test was performed using a Thermo Varioskan Lux™ microplate reader. The following standards were prepared for a calibration curve: 0.01 ppm, 0.1 ppm, 0.5 ppm, 1 ppm, 2 ppm, 3 ppm, 4 ppm. The Thermo Varioskan Lux™ was set to read the absorbance of a given well at 664 nm. The absorbance of the standards was measured and plotted against concentration to create a calibration curve.

[0091] Example 1: Mass transfer efficiency of ozone into a water stream This example relates to determining under what conditions the proposed method provides the highest mass transfer efficiency of ozone. The system used was the one shown in Figures 14A to 14C, with a treatment chamber of about 3 L volume. The following process factors were varied one at a time or simultaneously: (a) impeller speed; (B) pressure of the fluid in the treatment chamber; (c) residence time of the fluid in the treatment chamber; and (d) mass rate of injection of the reagent (in this case, ozone gas). The injection pressure of the reagent (e.g., ozone gas, including mixtures of oxygen and ozone gas) was always kept constant at 3 bar for all runs. In this way, a reagent pressure greater than or equal to the pressure of the treatment chamber was achieved in all tests. The general mass balance for ozone can be expressed as: Residual ozone = Transferred ozone - Decomposed ozone - Ozone reacted with substrate (Equation 1).

[0092] All tests were conducted under specific water quality conditions to simplify Equation 1, which will allow the use of dissolved oxygen as a surrogate indicator of mass transfer efficiency. Specifically, all runs were conducted using clean tap water, further filtered with a granular activated carbon (GAC) filter to remove all residual combined chlorine present in the water stream as well as to reduce the organic carbon of the fluid. In this case, it can be assumed that: Ozone reacted with substrate = Ozone transferred to liquid - Decomposed ozone (Equation 2).

[0093] Given the constant water quality used in the runs, it can also be realistically expected that the ozone decomposition term reported in Equation 1 (labeled as “Decomposed ozone”) will be primarily attributed to self-decomposition mechanisms. Therefore, the contribution of this term will be equal in all runs and can be approximated by a “constant”, which, although unknown, will be equal for all runs. In this case, Equation 1 simplifies to Equation 3: Residual ozone (liquid) = Ozone transferred (liquid) - Constant (Equation 3).

[0094] The simplified form of this equation allows for the measurement of residual ozone (dissolved) in the fluid (water) and its use as a representative of mass transfer efficiency. The higher the residual ozone measured, the higher the mass transfer efficiency.

[0095] The following factors were varied in each run to optimize mass transfer efficiency: (a) pressure established in the treatment chamber by a first pump located immediately upstream of the treatment chamber; (B) mass injection rate of the reagent (in this case, ozone gas) established by controlling the concentration of ozone gas injected between the pump and the treatment chamber; (c) residence time in the treatment chamber; (d) mixing conditions in the treatment chamber established by setting the impeller speed at the desired rotational frequency.

[0096] These factors were varied in each run using controllable variables or indirectly by changing flow rate (residence time) and pressure (using valves located downstream of the system). Factorial experimental design was developed and executed varying the following factors: (a) impeller speed = [0-60 Hz], (B) ozone mass injection rate = [54-120 g / hr], (c) fluid residence time = [8-40 seconds]. Multiple runs allowed implicitly varying the pressure in the treatment chamber, which varied between 0.5 bar and 3 bar (as absolute pressure). It should be noted that due to the simultaneous action of the feed pump (push) and the impeller speed (pull), some runs experienced a pressure in the treatment chamber lower than atmospheric pressure. By reversing the direction of rotation of the impeller located in the treatment chamber, higher pressures (up to 3 times) could be tested. According to the results reported below, higher pressures up to 10 bar would result in further improvement of the process performance.

[0097] A total of 84 tests were performed. As response variable, all tests were uploaded to a statistical software package (Design Expert, Stat-Ease Inc., Minneapolis, USA). The data analysis workflow included: (1) data loading, (2) model selection, (3) ANOVA test, (4) model quality assessment, (5) graphics generation. Data loading in the Design-Expert software included inputting the 84 tests performed under the conditions specified in Materials and Methods, and declaring the factors and response to be analyzed. Model selection included comparing the ability of various models available in the software library to predict the response using the corresponding factors varied in the experiment. Specifically, the software generated a table summarizing the goodness of fit of the following model types: linear model, two-factor interaction model, quadratic model, cubic model, and quartic model. Model suitability was evaluated according to the following parameters: (1) model p-value, (2) lack of fit p-value, (3) adjusted R-squared, and (4) predicted R-squared. Based on these four parameters, the software provided recommendations to ensure the statistical reliability of the selected model. In addition, further statistical screening of each model factor of the selected model was performed. This was done by performing additional statistical tests that included selecting and deselecting each model term, and using adjusted R-squared calculations as criteria to perform a fit test of the resulting equations. For more information on the mathematical methods used by the Design-Expert software, see the software manual.

[0098] Once the model structure is finalized, each term included in the model is subjected to significance evaluation using ANOVA test on the response variable measured during the experiment (in our case, dissolved ozone). Specifically, the software generates an ANOVA table indicating the sum of squares, degrees of freedom, mean square, F-value, and p-value for each term. The p-value is used to judge the significance of each term included in the model at a user-selected p-threshold. In this experiment, the p-threshold is set to 0.1. The output generated by Design-Expert includes the following: (a) model diagnostics and tables, including normal probability plot of model residuals; residual vs. predicted values and predicted vs. observed values plots; (B) single-factor effect plots for all factors in the model; (c) two-factor response surface plots.

[0099] Referring to FIGS. 15A-15B, based on the ANOVA test performed on the entire set of runs collected under Example 1, it was found that impeller speed and ozone mass rate in the treatment chamber have high statistical significance. Moreover, and surprisingly, residence time and pressure in the treatment chamber also have high statistical significance when considered in combination with other factors, such as: impeller speed with pressure; ozone mass rate with residence time; and residence time with pressure. Thus, the process can be operated by adjusting the important factors involved so that the positive effects associated with the factor interactions are maximized.

[0100] Impeller speed plays a very important role in enhancing the gas-liquid mass transfer (FIG. 15A). All other factors included in the model (residence time, ozone gas mass rate) were held constant and equal to their average values tested in Example 1. FIG. 15A clearly shows that changing the speed from 0 to 60 Hz (0 to 3,600 rpm) increased the ozone dissolution efficiency, and thus the mass transfer efficiency, by more than 400%. In fact, the residual ozone concentration at 0 Hz was about 2 mg / L, and increased to more than 8 mg / L when the impeller speed was increased to 60 Hz. FIG. 15A also shows that the maximum improvement is achieved when the impeller speed is controlled to values greater than 30 Hz (1,800 rpm), with the range of 40-55 Hz (2400 - 3300 rpm) showing the maximum improvement.

[0101] Moreover, the residence time required to achieve high ozone mass transfer is very low, with the applied residence time never exceeding 100 seconds, and even never exceeding 40 seconds. As shown in FIG. 15B, the mass transfer is almost complete at a residence time as low as 35 seconds. This time is substantially lower than any other commercially available ozonation process or method we are aware of, which typically employs a residence time exceeding 300 seconds (or 5 minutes). Being able to achieve almost complete mass transfer in less than 300 seconds is a very beneficial feature of this method.

[0102] As Figure 15B shown, pressure in combination with the average mixing conditions given by impeller speed setting at 30 Hz plays a very important role in establishing higher mass transfer rates. In fact, when the pressure in the treatment chamber was increased from 0.7 bar to 2.3 bar, respectively, the dissolved ozone increased from 1.9 mg / L to 5.9 mg / L (all other conditions being the same). Based on the solubility of ozone in water as a function of pressure, the beneficial effect of pressure on dissolved ozone is expected to continue up to 10 bar. Increasing the pressure can also further reduce the mixing intensity (controlled by the impeller speed) and the residence time (controlled by the system flow) to achieve complete treatment of the contaminated fluid.

[0103] Example 2: Use of two degradation reagents in this process This example aims to determine how the performance of the process is when using two reagents (ozone (O3) and hydrogen peroxide (H2O2)) for which the reaction stoichiometry and the amount of hydroxyl radical generation are known, and whether the process leads to a consumption of dissolved ozone and hydrogen peroxide close to the molar ratio of 2 of ozone to hydrogen peroxide, which is the best condition based on the stoichiometry of the reaction in Equation 4: 2O3 + H2O2 = 2OH + 3O2 (Equation 4).

[0104] Ozone and hydrogen peroxide were dosed at different molar ratios and process conditions. The process factors were varied: (a) impeller speed; (B) ozone mass transfer and (c) fluid residence time in the treatment chamber. The hydrogen peroxide concentration was kept constant at a value in the range of 9-10 mg / L. The actual hydrogen peroxide concentration in the fluid stream was measured before and after the addition of hydrogen peroxide (initial and final). Residual ozone was also predicted based on the results modeled in Example 1 under almost identical water quality conditions (without the addition of hydrogen peroxide). The injection pressure of the reagents (e.g., ozone gas, including a mixture of oxygen and ozone gas) was kept constant at 3 bar in all tests. In this way, a reagent pressure greater than or equal to the pressure of the treatment chamber was achieved in all tests.

[0105] The following factors were systematically varied: (a) mixing conditions in the treatment chamber by setting the impeller speed at the desired rotational frequency; (B) flow rate / residence time in the treatment chamber; (c) flow rate / pressure established in the treatment chamber by the first pump located just upstream of the treatment chamber; (d) mass ratio between ozone and hydrogen peroxide, which was established in each run by controlling the ozone gas concentration between the injection pump and the treatment chamber and keeping the hydrogen peroxide concentration at about 9-10 mg / L.

[0106] A total of 21 tests were performed. As response variable, the residual (dissolved) hydrogen peroxide concentration was measured experimentally. Using a statistical software package (Design Expert, Stat-Ease Inc., Minneapolis, USA), a response surface of the mass ratio of ozone divided by hydrogen peroxide could be constructed. This calculation was performed by estimating the incremental ozone depletion caused by hydrogen peroxide. This value was divided by the experimentally observed hydrogen peroxide depletion. By adjusting for the molecular weights of the two chemicals, the ideal process under optimal process conditions would approach a mass ratio of ozone to hydrogen peroxide equal to 2 x 48 / 34 = 2.8. Basically, for every milligram of hydrogen peroxide dosed, 2.8 milligrams of ozone would disappear from the system and be converted into hydroxyl radicals.

[0107] The data analysis workflow included the following steps: (1) data loading, (2) model selection, (3) ANOVA test, (4) model quality assessment, and (5) graph generation. The data loading in the Design-Expert software included the input of the 21 tests performed under the conditions specified in Materials and Methods, and the declaration of the factors and response to be analyzed. Using a statistical model, the process could be optimized by requiring the maximization of ozone: the maximization of the mass ratio response variable of hydrogen peroxide while keeping the other parameters unconstrained. The optimal parameter range for the generation of hydroxyl radicals from the reaction between ozone and hydrogen peroxide was: impeller speed = 20 to 60 Hz; ozone mass rate = 45 to 160 g / hr; residence time = 1 to 36 sec. Under these conditions, the peroxide reaction efficiency was 65.5% to 110%. These results were obtained during the process operated in the treatment chamber at 0.6 to 3 bar absolute pressure.

[0108] As can be seen from Table 1 and Figure 16A 、 Figure 16B there are process conditions in which the molar ratio of ozone to hydrogen peroxide (R_03_H202) approaches the stoichiometric value of 2. There is one case (test 19) that is close to 1.97. This corresponds to a reaction efficiency that is essentially equal to 100%.

[0109] The most important process parameters for establishing a high reaction efficiency between ozone and hydrogen peroxide are: (a) impeller speed and ozone mass injection rate. While the residence time is not an important parameter by itself, it becomes very important if considered in combination with impeller speed and ozone injection rate. These significant two-factor interactions highlight the industrial relevance of the process.

[0110] Table 1

[0111] Example 3: Application of the method to pollutants This example relates to determining the efficacy of the method on real micro pollutants and other conventional pollutants. Spiked and non-spiked tests were performed. Spiked tests were performed in two different water matrices (dechlorinated-GAC (granular activated carbon) treated tap water, adjusted for oxidant and radical demand by addition of nitrite and TOC (total organic carbon)). In this example, the method enhances the degradation of the pollutants by increasing pressure and mixing (applied simultaneously), resulting in a significant acceleration of the kinetics. Therefore, the treatment dose (i.e. concentration-time (CT) dose) required to achieve the degradation of the pollutants is significantly lower than the doses used in conventional technologies.

[0112] The same method as described above was tested in real tertiary treated wastewater, with different oxidants (alone and in combination). In this case, GAC filtered secondary effluent obtained from a municipal wastewater treatment plant was used. The pollutants followed during the study were already present in the influent wastewater stream. The process was experimentally and numerically optimized in terms of type and amount of reagents used by implementing four different reagent combinations in the treatment system: (a) ozone alone; (B) ozone with hydrogen peroxide; (c) ozone with sodium hypochlorite (NaCIO); (d) sodium hypochlorite alone. The study also aimed to determine suitable alternatives for advanced process control; therefore, during the experimental runs, the effluent values of absorbance at 254 nm and the residual values of the added reagents (such as ozone, hydrogen peroxide, and sodium hypochlorite) were measured for each tested condition. The correlation between these optical parameters, process conditions, and micro pollutants was developed to verify the possibility of using alternative parameters to control the disclosed process.

[0113] Advanced oxidation and reduction processes are known to be effective against micro pollutants and other pollutants present in water and wastewater. Previous studies have shown that to achieve the expected removal rates, a minimum CT value requirement must be met. This CT value requirement depends on the type of pollutant being removed and the water matrix. For the oxidation of micro pollutants, a typical concentration and contact time for an ozonation process operated in conventional technology is reported to be an initial ozone concentration of 1-10 mg / L and a contact time of 10-30 min. Combining these values would result in a CT dose range of 10 to 300 mg / L min. In the method described herein, the high enhancement rate resulting from the high pressure and high mixing leads to optimal performance, but the CT dose is much shorter. The following example tests the process at different CT values, ranging from 0 to 10 mg / L min (for the case of spiked micro pollutants) and 0 to 1 mg / L min (for the case of indigenous micro pollutants in wastewater).

[0114] The following parameters were systematically varied: (a) mixing conditions in the treatment chamber established by setting the impeller speed at the desired rotational frequency; (B) flow rate / residence time in the treatment chamber; (c) flow rate / pressure established in the treatment chamber by the first pump located immediately upstream of the treatment chamber; and (d) ozone mass rate injected into the system. The spiking study was tested 54 times and the wastewater study was tested 25 times. The spiking study was performed on two wastewater qualities, designated "high" and "low." The high quality was obtained from GAC filtered dechlorinated tap water, while the low quality was the same water spiked with 5 mg / L nitrite and 10 mg / L TOC (using methanol). The data collected were analyzed using a statistical software package (Design Expert, Stat-Ease Inc., Minneapolis, USA). The data analysis workflow included: (1) data loading, (2) model selection, (3) ANOVA test, (4) model quality assessment, and (5) graph generation. The data loading in the Design-Expert software included the entry of the 54 tests performed under the conditions specified in Materials and Methods, as well as the declaration of the parameters and responses to be analyzed. Similarly, the 25 tests performed with real wastewater created a Design-Expert file.

[0115] Optimization simulations were performed on the spiking study and the wastewater study. The optimizer was set to maximize the removal efficiency of pBCA and all other microcontaminants spiked in the water, while keeping the other parameters within their tested ranges. Table 2 shows the top 10 optimal combinations. There are several combinations with CT (in mg / L min) less than 7. A similar optimization study was repeated in the wastewater study with the goal of maximizing the removal of PFOA, the results of which are shown in Table 3. Using the influent (Inf) data, the best conditions reported in Table 3 were able to achieve the following removal efficiencies: COD reduction = 57%, absorbance at 254 nm = 52%, PFHxA = 56%, PFOA = 14%, THM = not formed relative to the influent baseline. PFHxA is perfluorohexanoic acid. PFOA is perfluorooctanoic acid. THM is trihalomethane.

[0116] Reference is made to Tables 2, 3, and Figures 17 to 22The spiked experiments confirmed the superior performance of the test method implemented at high pressure, high mixing, and short residence times. The CT dose required to remove the micropollutants from the fluid was less than 10 mg / L min. Excellent process performance was obtained with tertiary treated wastewater, where the CT values tested were all less than 1 mg / L min. Nonetheless, the removal rates of the inherent micropollutants in the water body were still over 80% under the optimized conditions. Such high removal performance at such low CT dose is unprecedented. Ozone doses greater than 6 mg / L and hydrogen peroxide doses greater than 4 mg / L resulted in the removal of per- and polyfluoroalkyl substances (PFAS) compounds, confirming that the advanced reduction pathways enabled by the tested process conditions can very rapidly and cost-effectively defluorinate long-chain PFAS.

[0117] Table 2

[0118] Table 3

[0119] Additional tests were performed to verify the novelty and non-obviousness of the new method and system disclosed in the present invention, which uses an oxidizing agent as reagent (i.e., sodium hypochlorite). Specifically, we evaluated the performance of the current method and system by performing the following experiment: first, the reagent (i.e., sodium hypochlorite) was dosed at a given concentration and contact time. Second, the same experiment was performed with the same concentration and contact time using a conventional magnetic stirrer (intended to simulate a conventional mixing system operating at mixing intensity values not exceeding 0.25 W / L). In fact, it should be noted that the new method and system operates at mixing intensity values > 0.7 W / L, while the control experiment (using a conventional magnetic stirrer) operates at typical mixing intensity values < 0.25 W / L, representing the upper value in the range of mixing intensities employed by actual scale wastewater treatment plants. It is also worth noting that operating at high mixing intensities is a way to achieve high Gt values (where Gt is a dimensionless number used in coagulation / flocculation studies, whose value is equal to the product of the velocity gradient G (units: s"1) and the mixing time t (units: s)). Therefore, the novel method and system disclosed herein are also characterized by the ability to operate at much higher G*t values than conventional methods for a given mixing time, since G*t can be expressed as G (s -1 ) * t (s"1) = (P / (η*V))0.5*t, where P is the input power (W), η is the dynamic viscosity of the fluid flow (Pa s), V is the volume of the treatment chamber to which the power input is applied (m 3), t is the mixing time (seconds). All the remaining process parameters used in the parallel experiments, including chemical reagent dosage (i.e., initial sodium hypochlorite concentration) and contact time (i.e., time used for the contaminated fluid to be in contact with sodium hypochlorite) were kept the same.

[0120] After the treatment was completed, to compare the performance of the innovative method and system in comparison to the state-of-the-art (represented by the conventional magnetic stirring batch experiment), the determined effluent water quality parameter was the total residual chlorine. From the total residual chlorine, the key quantity to estimate the reactivity of the process can be assessed: the total chlorine (or sodium hypochlorite) reacted. This is the difference between the initial sodium hypochlorite (spiked in the experiment based on the initial sodium hypochlorite stock concentration) and the residual total chlorine (or sodium hypochlorite) measured at the end of the experiment.

[0121] The results clearly indicate that when dosing sodium hypochlorite with the new method and system disclosed in the present application, the reagent reacted (difference between the amount of hypochlorite salt dosed in the water and the amount measured after the designed contact time) is significantly higher than in the control experiment (i.e., the magnetic stirring batch system operated under the same process conditions, but with a mixing intensity of 0.25 W / L). More specifically, when an initial hypochlorite salt concentration of 5 mg / L was incorporated in both systems and kept the same contact time, the effluent treated by the new method and system had a residual hypochlorite salt concentration of 2.5 mg / L, while 4 mg / L was detected in the magnetic stirring batch system. Similarly, when 16 mg / L was incorporated as initial sodium hypochlorite concentration and kept the same contact time in both systems operated at different mixing intensities, the effluent produced using the new method and system (operated at a mixing intensity of 0.7 W / L) had 5 mg / L of residual hypochlorite salt, while 12 mg / L was detected in the magnetic stirring batch system. If the amount of chlorine (or sodium hypochlorite) effectively consumed is considered, the corresponding values for the new method and system described in the present application are significantly higher (specific data: Experiment one, 2.5 mg / L vs. 1 mg / L; Experiment two, 11 mg / L vs. 4 mg / L). This much higher reactivity recorded for the method and system reported in the present application (operated at mixing intensities < 0.7 W / L) proves the production of much higher concentrations of reacted species than in the state-of-the-art method and system operated at mixing intensities < 0.25 W / L.

[0122] To further confirm this, a final experiment was performed by comparing the reactivity of a method and system operated with a single pump (representative of the improvements that can be obtained by the person of ordinary skill in the art) with the method and system according to the operation reported and described in the present application. This experiment was performed by injecting the same amount of chemicals with the same contact time into the first method and system or the second method and system. The chlorine stock concentration and the water used in the test were the same. The results confirmed that when the reagent (i.e. sodium hypochlorite) is injected in a system configured according to the present application (i.e. using one or more pumps operating in series with a mixing intensity of 0.7 W / L, where the reagent is released in the high pressure / high mixing intensity zone generated by the method and system disclosed herein). It is worth noting that the results obtained with a single pump are not significantly different compared to the magnetic stirring system. This confirms that the simultaneous use of high mixing intensity (> 0.7 W / L) and pressure (higher than atmospheric pressure > 0.1 bar) are viable conditions of the present application. On the contrary, when two or more pumps in series are used to simulate the method and system disclosed in the present application (i.e. a method operating with a mixing intensity > 0.7 W / L and a pressure higher than atmospheric pressure > 0.1), the reacted sodium hypochlorite is significantly higher, confirming the important role played by the mixing intensity, the pressure and the other thermodynamic and physico-chemical conditions established with the new method and system described in the present application.

[0123] The unique process conditions established in the disclosed method and system are significantly different from the process conditions reported in the prior art. Considering the well-known mixing parameter reported in water treatment textbooks, which is widely used to optimize the mixing conditions in various treatment processes, i.e. the G parameter (also known as velocity gradient, measured in s). It should be noted that the G parameter is mathematically related to the mixing intensity (defined in our application as the mixing power input per volume) by the following relationship: G (s) = (P / (η * V)) ≥ 0.5, where P is the input power input (W), η is the dynamic viscosity of the fluid flow (Pa s), V is the volume of the treatment chamber where the power input is applied (m 3 ). By rearranging the above equation, it is possible to derive the mathematical relationship that connects the velocity gradient (G, s) and the mixing intensity (P / V) as defined in the present application. After rearranging, we obtain: P / V = G 2 * η, where the units of P / V are W / m 3 .

[0124] Considering that the G value of the process conditions requiring the highest G value in water treatment textbooks (i.e. the fast stirrers) is typically in the range 300-500 s ( -1 ). Using a dynamic viscosity value of 10 -3 Pa s (typical of water), it is possible to calculate that the higher mixing intensity values related to fast mixing applications are in the range 90-250 W / m 3(or 0.09-0.25 W / L). It should also be mentioned that these conditions are usually applied close to atmospheric pressure and / or very short contact times <10 seconds. Increasing, maintaining and controlling the conditions in the treatment chamber to be sufficient to achieve both high mixing intensity (>0.25 W / L) and high pressure (>0.1 bar above atmospheric pressure) for contact times sufficient to achieve not only mixing but also degradation of the pollutants in the fluid stream is another significant feature of the disclosed method and system. Thus, the exceptionally significant results observed in the experiments in terms of fluid reactivity and production of reactive species can be unambiguously attributed to the use of very high mixing intensity (>700 W / m 3 or 0.7 W / L), certainly much higher than the mixing intensity usually applied in the prior art (i.e. 90-250 W / m 3 or 0.09-0.25 W / L). Finally, it should also be noted that these values reported in the prior art are usually applied in coagulation / flocculation applications, whereas our present application preferably focuses on optimized process conditions for achieving degradation; in particular, but not limited to, conditions required to achieve high speed disinfection, oxidation and reduction of contaminated fluids. For these applications, the mixing intensity applied in the prior art is even lower than the mixing intensity reported above for coagulation and flocculation processes, not exceeding 100 W / m 3 or 0.1 W / L.

[0125] The method and system reported in the present application can be further configured as a flow chemistry process and device to produce desired compounds in a liquid stream. The method and system can be operated either in-line with the main fluid line or in a side-stream mode. In the latter configuration, the desired compounds can be dosed into the main fluid in real time or stored and dosed later. Non-limiting examples of such compounds or classes of compounds produced include: (a) pharmaceutical ingredients; fine chemicals; agrochemicals; energetic materials; specialty chemicals; fragrances and flavors; dyes and pigments; nanomaterials; quantum dots.

[0126] The novelty of the present application will be apparent to those skilled in the art upon review of the specification. However, it is to be understood that the scope of the claims should not be limited by the examples, but rather should be given the broadest interpretation consistent with the language and intent of the claims and specification.

Claims

1. A method for degrading compounds in a liquid stream, the method comprising: A pump (16) is provided, which is fluidly connected in series with a processing chamber (12) containing a mixer (17), and a reagent injector is provided between the pump (16) and the processing chamber (12); The liquid flow is introduced into the inlet (14) of the pump (16). The liquid flow is introduced into the inlet (14) of the pump (16). The pump (16) is operated to direct the liquid flow to the inlet of the processing chamber (12) to generate a pressure increase of 0.1 bar to 10 bar between the pump inlet (14) and the processing chamber (12); The degradation reagent is introduced into the liquid flow through the injector at a pressure greater than or equal to the pressure between the pump inlet (14) and the treatment chamber (12); as well as The mixer (17) is operated to mix the degradation reagent in the liquid stream at a mixing intensity, which is the mixing power input per volume, wherein the mixing power input is the power of the mixer (17) and the volume is the volume of the treatment chamber (12), in the range of 0.7 W / L to 700 W / L, to intentionally create the desired physical and chemical conditions while enhancing mass transfer and degradation of one or more contaminants present in the liquid stream.

2. The method according to claim 1, wherein the liquid flow is a water flow.

3. The method according to claim 1 or 2, wherein the degradation reagent is gaseous.

4. The method according to any one of claims 1 to 3, wherein the degradation agent comprises ozone.

5. The method according to any one of claims 1 to 4, wherein the mixing intensity is in the range of 60 W / L to 360 W / L.

6. The method according to any one of claims 1 to 4, wherein the mixing intensity is in the range of 120 W / L to 300 W / L.

7. The method according to any one of claims 1 to 6, wherein the pressure increase between the pump inlet (14) and the treatment chamber (12) is in the range of 1 bar to 5 bar.

8. The method according to any one of claims 1 to 7, wherein the liquid flow has a residence time in the range of 0.1 seconds to 100 seconds between the inlet (14) of the pump and the outlet (15) of the processing chamber (12).

9. The method according to any one of claims 1 to 8, further comprising introducing hydrogen peroxide into the liquid stream before introducing the liquid stream into the inlet (14) of the pump (16).

10. The method of claim 9, wherein the degradation reagent is introduced into the liquid stream in an amount such that the molar ratio of the degradation reagent to the hydrogen peroxide is from 0.1:1 to 10:

1.

11. The method according to any one of claims 1 to 10, wherein valves (131, 141) are provided downstream of the processing chamber (12) and said valves (131, 141) are operated to control the pressure between the pump inlet (14) and the processing chamber (12).

12. The method of claim 11, wherein the valves (131, 141) include a back pressure regulator.

13. The method according to any one of claims 1 to 12, further comprising exposing the liquid stream to ultraviolet light downstream of the processing chamber (12).

14. The method according to any one of claims 1 to 13, wherein the injector comprises a high-pressure needle injector.

15. The method according to any one of claims 1 to 14, wherein the mixer (17) comprises a centrifugal mixer.

16. The method according to any one of claims 1 to 15, wherein the mixer (17) comprises a powered rotating impeller.

17. The method according to any one of claims 1 to 16, wherein the pump (16) is a first pump (16a, 146) and the mixer (17) includes a second pump (17a, 147).

18. The method according to any one of claims 1 to 17, wherein the processing chamber (12) includes a baffle to improve mixing efficiency.

19. The method according to any one of claims 1 to 17, wherein the degradation reagent is selected from chlorine, chlorine dioxide, performic acid and peracetic acid.

20. The method according to any one of claims 1 to 17, wherein the liquid is preheated to a temperature in the range of 20°C to 60°C before being introduced into the pump (16).

21. The method according to any one of claims 1 to 17, wherein the degradation reagent is introduced into the liquid stream in a pulsed manner to optimize reagent distribution.

22. The method according to any one of claims 1 to 17, wherein the liquid flow is subjected to an acoustic or ultrasonic field within the processing chamber (12) to further enhance mixing and degradation.

23. The method according to any one of claims 1 to 17, wherein the mixing intensity is automatically adjusted based on real-time monitoring of a parameter selected from the liquid flow, including pH, redox potential, wall shear stress, vibration noise, flow rate, or turbidity.

24. A system for performing a method for degrading a compound in a liquid stream according to any one of claims 1 to 23, the system comprising: Inlet (14) for receiving liquid flow (18); The pressurization zone (11) is fluidly connected to the inlet (14); A fluid delivery device (16) is used to advance the liquid flow (18) into the processing chamber to generate a pressure between 0.1 bar and 10 bar; Multiple degradation reagent injection zones (13) are used to inject degradation reagents into the liquid stream (18); A centrifugal mixer (17) for mixing the degradation reagent with the liquid stream (18) in the treatment chamber, wherein the treated liquid stream flows out of the treatment chamber through an outlet (15), the mixer (17) being designed to operate the mixer (17) to mix the degradation reagent in the liquid stream at a mixing intensity (i.e., mixing power input per volume), wherein the mixing power input is the power of the mixer (17), and the volume is the volume of the treatment chamber (12), in the range of 0.7 W / L to 700 W / L, to intentionally generate the physical and chemical conditions required to simultaneously enhance the mass transfer and degradation of one or more contaminants present in the liquid stream.

25. The system of claim 24, further comprising: An extension chamber (21), inserted between the first degradation reagent injection area (13a) and the second degradation reagent injection area (13b), is used to extend the path length of the treatment chamber; and The fluid delivery device includes a pump (16) having an impeller that rotates in the same direction as the centrifugal mixer (17), thereby providing a longer residence time for the fluid flow (18) in the processing chamber.

26. The system according to claim 25, wherein, The fluid delivery device (16) has an impeller that rotates in the opposite direction to the centrifugal mixer (17), such that the impeller rotates in one direction and the centrifugal mixer (17) rotates in different directions, thereby providing different mixing mechanisms for the liquid flow (18) in the processing chamber.

27. The system of claim 24, wherein the first degradation reagent injection zone (13a) is located upstream of the inlet (14) to provide a longer residence time of the first degradation reagent in the liquid flow (18) without increasing the residence time of the liquid flow (18) in the processing chamber.

28. The system of claim 24, wherein the first degradation reagent injection zone (13a) includes two ports for simultaneously injecting both the first degradation reagent and the third degradation reagent, and the second degradation reagent injection zone (13b) includes two ports for simultaneously injecting both the second degradation reagent and the fourth degradation reagent. This allows more than two degradation reagents to be injected into the liquid stream (18).

29. The system of claim 24, further comprising: The third degradation reagent injection zone (13c) is located upstream of the inlet (14) and the fourth degradation reagent injection zone (13d) is located downstream of the outlet (15); wherein the third degradation reagent is injected into the liquid stream (18) in the third injection zone (13c) and the fourth degradation reagent is injected into the treated liquid stream (19) in the fourth injection zone (13d), thereby allowing the degradation reagent to be injected into the treated liquid stream (19) for further treatment of the liquid stream.

30. The system of claim 24, further comprising: A post-treatment chamber (71) is inserted downstream of the outlet (15), a fourth degradation reagent injection zone (13d) is inserted between the outlet (15) and the post-treatment chamber (71) for injecting a fourth degradation reagent into the treated liquid stream exiting the outlet (15), wherein the post-treatment chamber (71) has its own post-treatment outlet (75), and the system includes a fifth degradation reagent injection zone (13e) downstream of the post-treatment outlet (75) for injecting a fifth degradation reagent as the treated liquid stream (19) exits the system, thereby allowing further processing of the liquid stream downstream of the mixing zone (12).

31. The system of claim 24, further comprising: Insert the downstream post-treatment chamber (71) of the outlet (15), wherein the post-treatment chamber (71) is equipped with an ultraviolet (UV) lamp (81) for further treatment of the liquid flow in the post-treatment chamber (71), thereby allowing UV treatment of the liquid flow downstream of the mixing zone (12).

32. The system of claim 24, further comprising: An extension chamber (21) is inserted between the first degradation reagent injection area (13a) and the second degradation reagent injection area (13b), wherein the extension chamber (21) is equipped with an ultraviolet (UV) lamp (91) for treating the liquid stream (18) in the extension chamber (21), thereby allowing the liquid stream (18) to be UV treated in the treatment chamber.

33. The system according to claim 24, further comprising: An extension chamber (21) is inserted between the first degradation reagent injection area (13a) and the second degradation reagent injection area (13b), wherein the extension chamber (21) is equipped with a filter unit for treating the liquid stream (18) in the extension chamber (21), thereby allowing the liquid stream (18) to be filtered in the treatment chamber.

34. The system according to claim 24, wherein, The fluid delivery device is specifically the first pump (16a), and the centrifugal mixer is specifically the second pump (17a). Although the fluid flow (18) flows through the elements in the same order as in the system of claim 24, the various elements are configured differently relative to each other, thereby providing different configurations of the system elements while maintaining the same flow order of the fluid.

35. The system according to claim 24, wherein, The extension chamber (21) is removed, so that the first degradation reagent injection area (13a) and the second degradation reagent injection area (13b) are adjacent to each other.

36. The system of claim 24, further comprising: A pressure regulator (131) is inserted between the mixing zone (12) and the outlet (15), wherein the pressure regulator (131) can be operated to help maintain the desired pressure in the processing chamber, thereby providing a means for pressure control in the processing chamber.

37. The system according to any one of claims 24 to 36 further includes a sensor for real-time monitoring of pressure and mixing intensity within the processing chamber (12).

38. The system according to any one of claims 24 to 36, wherein, The reagent injector includes a heating element to preheat the degradation reagent before it is introduced into the liquid flow.

39. The system according to any one of claims 24 to 36 further includes a programmable control unit for adjusting the operation of the pump (16) and the mixer (17) based on feedback from the sensors.

40. The system according to any one of claims 24 to 36, wherein the treatment chamber (12) is coated with a catalytic material to enhance the degradation of pollutants.

41. The system according to any one of claims 24 to 36, wherein the system is configured to operate in a batch mode or a continuous stream mode.

42. The system according to any one of claims 24 to 36, wherein the degradation reagent injection zone (13) is equipped with a flow meter to precisely control the amount of reagent introduced into the liquid flow.

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