Reactor for treating a fluid to be treated, in particular a biological treatment reactor, and associated treatment method

Abstract

The invention relates to a reactor comprising a cell having a bottom (32) and a supply line (40, 40A, 40B) for supplying fluid to be treated into an interior volume of the cell, the supply line (40, 40A, 40B) extending into the cell facing the bottom (32) along a line axis (A-A'), the supply line (40, 40A, 40B) having fluid injection openings (50A, 50B) for fluid to be treated that open towards the bottom (32) while being spaced apart along the line axis (A-A'). The reactor comprises a fluid deflector (46) which is positioned between the bottom (32) and the injection openings (50A, 50B), the fluid deflector (46) having an undulating surface (48) placed facing the injection openings (50A, 50B), the undulating surface (48) having recesses and protuberances extending at least partially along a direction intersecting the line axis (A-A') in projection in a horizontal plane.

Description

[0001] TITLE: Reactor for treating a fluid to be treated, in particular a biological treatment reactor, and associated treatment process. The present invention relates to a reactor for treating a fluid to be treated, in particular a biological treatment reactor, comprising:

[0002] a cell with a base, the cell defining an internal volume for receiving and processing the fluid to be treated

[0003] at least one supply line for the fluid to be treated into the internal volume, the supply line extending at least partially into the cell opposite the bottom along a pipe axis, the supply line having at least two openings for injecting the fluid to be treated into the cell opening towards the bottom and being spaced along the pipe axis,

[0004] a treated fluid outlet system obtained after treatment.

[0005] Such a reactor is notably a sequencing batch reactor (or "SBR").

[0006] This type of reactor features a fluid treatment cell with a continuous internal volume, in which the following steps are carried out successively and sequentially: fluid inlet, fluid aeration, aeration interruption, settling (involving partial clarification of the fluid), and finally, discharge of the treated fluid obtained after clarification. In some embodiments, the fluid inlet and treated fluid discharge steps are simultaneous.

[0007] The different stages of the aforementioned treatment take place during predefined and programmable time intervals, the set of stages constituting a cycle.

[0008] In a given cycle, after the introduction of the fluid to be treated and generally a period of non-aeration (anaerobic and / or anoxic), the aeration of the internal volume of the cell by injection of a gas containing oxygen causes an oxidation of the carbon fraction and of the nitrogen pollution present mainly in the form of ammonium ions present in the fluid to be treated into nitrites and / or nitrates.

[0009] Then, once aeration is stopped, anoxic conditions generally occur, causing denitrification to produce nitrogen gas.

[0010] Denitrification often continues during settling. Settling is followed by the removal of the treated fluid to the surface, which may occur simultaneously with the introduction of the fluid to be treated for the next cycle. Excess sediment may be removed when its level rises above a certain threshold.

[0011] To simplify the introduction of the fluid to be treated into the internal volume, supply lines are positioned directly opposite the bottom of the cell. These supply lines have fluid injection openings that are directed towards the bottom of the cell. Thus, the fluid injected towards the bottom of the cell is deflected by the bottom and rises, pushing upwards the fluid already present in the internal volume, creating a piston-like effect.

[0012] To limit the footprint of the structures and / or to increase their treatment capacity, it is known to increase their height, for example to heights of around 5 m to 8 m. A compromise must generally be found to allow for efficient sludge settling (requiring a relatively low water level), hydraulic constraints and construction possibilities, while respecting a minimum volume to guarantee biological treatment.

[0013] In such reactors, creating a piston effect within the internal volume during fluid injection is difficult. In particular, the jets of fluid to be treated, exiting the injection openings and directed downwards, tend to be redirected against each other in the space between the feed pipes, generating a highly inhomogeneous velocity field with localized velocity peaks.

[0014] For example, high velocity zones directed in the direction of the flow of the fluid to be treated in the supply lines are created between the supply lines, leading to the accumulation of solid materials in the dead zones located at the free end of the supply lines.

[0015] To overcome this problem, it is possible to redirect the flow of fluid to be treated, by impact with sails or coarse deflection elements which can lead to side effects such as the concentration of flow and therefore the accumulation of solid materials.

[0016] Furthermore, the construction of these elements is complex and requires a design specific to each installation, without necessarily achieving effective homogenization of the upward flow in the cell and consequently, a piston effect.

[0017] One aim of the invention is therefore to obtain a biological treatment reactor in which homogeneous velocity fields compatible with the constraints of the different fluids involved (clear water, loaded water, sludge, water containing fibers, gas, etc.) are obtained, by simple and reproducible means from one treatment installation to another.

[0018] To this end, the invention relates to a biological treatment reactor of the aforementioned type, characterized by at least one fluid deflector positioned between the bottom and the fluid injection openings to be treated, the fluid deflector having a corrugated surface having a succession of bumps and hollows defined between the bumps, the corrugated surface being placed opposite the fluid injection openings to be treated, with the hollows and bumps extending at least partly in a direction secant with the axis of the pipe projected into a horizontal plane.

[0019] The biological treatment reactor according to the invention may comprise one or more of the following features, taken individually or in any technically feasible combination:

[0020] The undulating surface presents a plurality of adjacent fluid guidance channels defined by the succession of troughs and bumps;

[0021] The hollows and bumps extend transversely with respect to the driving axis, preferably perpendicular to the driving axis;

[0022] The distance between two successive bumps on the corrugated surface along the pipe axis is greater than 0.5 times the distance between two successive fluid injection openings along the pipe axis;

[0023] The height separating the highest point of a bump and the lowest point of an adjacent hollow, taken perpendicular to the pipeline axis on the corrugated surface, is greater than 0.5 times the maximum axial extent of the fluid injection openings to be treated along the pipeline axis and is advantageously between 0.75 times and 4 times the maximum axial extent of the fluid injection openings to be treated along the pipeline axis;

[0024] The bumps exhibit a sinusoidal profile, a polygonal profile, notably trapezoidal, a comb-shaped profile, or a bell-shaped profile, in section in a vertical plane containing the axis of the pipe;

[0025] When projected onto the horizontal plane, the maximum width of the supply pipe is less than or equal to the maximum width of the corrugated surface, taken perpendicular to the axis of the pipe, the width of the corrugated surface being advantageously less than three times the maximum width of the supply pipe;

[0026] The fluid deflector is placed on the bottom, notably in the form of slabs or plates with a corrugated surface;

[0027] it includes at least one additional supply line for the fluid to be treated extending along the supply line, preferably parallel to the supply line, the additional supply line having at least two additional openings for injecting the fluid to be treated into the cell opening towards the bottom and being spaced along the axis of the line, the biological treatment reactor including an additional fluid deflector positioned between the bottom and the additional openings for injecting the fluid to be treated, the additional fluid deflector having a corrugated surface having a succession of bumps and hollows defined between the bumps, the corrugated surface being placed opposite the additional fluid injection openings, with the hollows and bumps extending in a direction secant to the axis of the line, in projection in the horizontal plane;

[0028] The fluid injection openings to be treated in the supply line and the additional fluid injection openings to be treated in the additional supply line are offset from each other along the axis of the line, with no fluid injection opening to be treated in the supply line being placed opposite an additional fluid injection opening to be treated along the axis of the line;

[0029] The supply line has at least two groups of at least two closely spaced openings for injecting the fluid to be treated into the cell, the two groups of closely spaced openings for injecting the fluid to be treated being spaced apart along the axis of the line, the additional supply line has at least two additional groups of at least two closely spaced additional openings for injecting the fluid to be treated into the cell, the two additional groups of closely spaced additional openings being spaced apart along the axis of the line;

[0030] The groups of closely spaced openings are axially offset relative to the additional groups of closely spaced openings;

[0031] The supply line defines fluid injection openings to be treated at a transverse distance from the line axis, on the side of the line axis directed towards the additional supply line and fluid injection openings to be treated at a transverse distance from the line axis, on the side of the line axis opposite the additional supply line, the fluid injection openings to be treated on the side of the line axis opposite the additional supply line being advantageously offset axially with respect to the fluid injection openings to be treated on the side of the line axis directed towards the additional supply line;

[0032] It includes a system for ventilating the fluid to be treated within the internal volume. The invention also relates to a method for treating a fluid to be treated, comprising the following steps:

[0033] supply of the fluid to be treated into the internal volume of a cell of a treatment reactor as defined above through the injection openings of the fluid to be treated in at least one supply line, the corrugated surface of the fluid deflector orienting the fluid to be treated in a direction secant to the axis of the line projected onto a horizontal plane,

[0034] treatment of the fluid to be treated within the internal volume of the cell,

[0035] outlet of the treated fluid by the outlet system.

[0036] The method according to the invention may comprise one or more of the following features, taken individually or in any technically feasible combination:

[0037] the fluid to be treated injected through each fluid injection opening forms a jet, the jet being oriented by the corrugated surface of the fluid deflector in a secant direction relative to the pipe axis projected into a horizontal plane;

[0038] It comprises at least one additional supply line for the fluid to be treated extending along the supply line, preferably parallel to the supply line, the additional supply line having at least two additional openings for injecting the fluid to be treated into the cell opening towards the bottom and being spaced along the axis of the line, the treatment reactor comprising an additional fluid deflector positioned between the bottom and the additional openings for injecting the fluid to be treated, the additional fluid deflector having a corrugated surface having a succession of bumps and hollows defined between the bumps, the corrugated surface being placed opposite the additional fluid injection openings, with the hollows and bumps extending in the secant direction with respect to the axis of the line,the process comprising the additional supply of the fluid to be treated into the internal volume through the additional fluid injection openings of the additional supply line, the fluid to be treated injected through each additional fluid injection opening forming an additional jet directed towards the fluid supply line, the additional jet being oriented in the secant direction relative to the axis of the line by the corrugated surface of the fluid deflector, each additional jet being emitted between jets emitted towards the additional supply line by the fluid injection openings of the fluid supply line;

[0039] the treatment step includes a sub-step of settling solid matter towards the bottom of the cell to form a treated fluid, advantageously a clarified fluid, towards the surface, the process preferably comprising successive cycles, each cycle comprising the steps of supplying the fluid to be treated, treating the fluid to be treated and removing the treated fluid, the removal of the treated fluid being advantageously carried out simultaneously with the supply of the fluid to be treated for the next cycle;

[0040] The treatment step includes, before the settling substep or substeps, a substep of aeration of the fluid to be treated using an aeration system to inject a gas containing oxygen into the cell, advantageously to generate oxidation of a carbonaceous fraction and / or a nitrogenous fraction present in the fluid to be treated, and a substep of interruption of the aeration of the fluid to be treated, advantageously to place the fluid to be treated in anoxia.

[0041] The invention will be better understood upon reading the following description, given solely by way of example, and made with reference to the attached drawings, in which:

[0042] - [Fig. 1] Figure 1 is a schematic view of a reactor according to the invention for the biological treatment of a fluid to be treated, during a treatment cycle of a biological treatment process;

[0043] - [Fig. 2] Figure 2 is a schematic view illustrating the bottom of a cell of the reactor of Figure 1, comprising a plurality of supply lines for the fluid to be treated into the internal volume, Figure 2 illustrating the jets generated from the injection openings of the supply lines;

[0044] - [Fig. 3] Figure 3 is a partial perspective view of two parallel and adjacent fluid supply pipes, each fitted with a corrugated surface fluid deflector, positioned between the bottom of the cell and the pipe;

[0045] - [Fig. 4] Figure 4 illustrates several possible profiles of corrugated surfaces for the fluid deflector of Figure 3;

[0046] - [Fig. 5] Figure 5 is a top view similar to Figure 2, of two parallel and adjacent fluid supply pipes, each equipped with groups of fluid injection openings to be treated, offset axially from each other along a pipe axis;

[0047] - [Fig. 6] Figure 6 is a view analogous to Figure 5, comprising groups of fluid injection openings to be treated configured to form a jet curtain;

[0048] - [Fig. 7] Figure 7 illustrates a fluid supply pipe having, on either side of a median plane passing through the pipe axis, groups of fluid injection openings to be treated, directed respectively towards an adjacent pipe located on the left and towards an adjacent pipe located on the right;

[0049] - [Fig. 8] Figure 8 illustrates in cross-section different configurations of fluid injection openings in a supply line; - [Fig. 9] Figure 9 illustrates a velocity profile of the injected flows between two lines (a) in a reactor equipped with flow deflectors with a corrugated surface according to the invention, and (b) in a biological treatment reactor of the prior art.

[0050] - [Fig. 10] Figure 10 is a flowchart illustrating the main steps of an example of a treatment process according to the invention;

[0051] - [Fig. 11] Figure 11 is a schematic life illustrating a variant of the treatment reactor according to the invention forming a pulsed sludge bed clarifier.

[0052] An example of a treatment reactor 10 according to the invention is schematically illustrated in Figure 1. The treatment reactor 10 is here a biological treatment reactor intended to treat a fluid to be treated 12 which is for example municipal wastewater or industrial wastewater.

[0053] The biological treatment reactor 10 is notably a sequential biological reactor (or "RBS").

[0054] More generally, the reactor is a treatment reactor, not necessarily biological, configured to treat water intended to be made potable or desalinated.

[0055] In the example of the biological treatment reactor 10 in Figure 1, the fluid to be treated 12 is intended to be treated by a succession of cycles, each comprising sequential treatment steps including the introduction of the fluid to be treated into the biological treatment reactor 10, a stage of no aeration (anaerobic and / or anoxic), aeration of the fluid to be treated in the biological treatment reactor 10 to oxidize the carbon and nitrogen fractions present in the fluid to be treated, optionally an interruption of the aeration to place the fluid to be treated in anoxic conditions in the biological treatment reactor 10 and generate denitrification, a settling stage in which suspended solids settle to the bottom of the biological treatment reactor 10, and in which a treated fluid 13 is produced near the surface of the biological treatment reactor 10, and an outlet, potentially simultaneous with the introduction stage.in which the treated fluid 13 is discharged from the biological treatment reactor 10.

[0056] The treated fluid 13 is, in this case, a clarified fluid, meaning it has a lower impurity content compared to the fluid being treated. Clarification aims to reduce, or even eliminate, suspended particles, microorganisms, and other contaminants to make the fluid cleaner.

[0057] As illustrated by Figure 1, the biological treatment reactor 10 comprises a cell 14 delimiting an internal volume 16 of treatment, a system 18 for distributing the fluid to be treated at the bottom of the cell 14 and a system 20 for aerating the fluid to be treated disposed in the cell 14. The biological treatment reactor 10 further comprises an outlet system 22 for evacuating the treated fluid out of the cell 14, and advantageously an outlet system 23 for sedimented solid matter.

[0058] It includes a sensor system 24 and a control unit 26, connected to the sensor system 24 and configured to monitor and control the biological treatment reactor 10 using the sensor system 24.

[0059] In this example, the cell 14 includes a capacity 30, which delimits the internal volume 16 between a bottom 32 preferably substantially horizontal, and a side wall 34, which projects out from the bottom 32. Advantageously, the height of the internal volume 16 is greater than 4 m, and in particular between 5 m and 8 m.

[0060] The interior volume 16 is configured to contain, for example, more than 150 m³ 3 of fluid, particularly between 150 m 3 and 10000 m 3 of fluid, preferably between 150 m 3 and 5000 m 3 .

[0061] With reference to figures 2 and 3, the fluid distribution system 18 comprises a plurality of supply lines 40 for the fluid to be treated 12, here arranged parallel to a line axis A-A', and extending to the vicinity of the bottom 32 of the tank 30.

[0062] As can be seen in Figure 2, it further includes an upstream manifold 42 for distributing the fluid to be treated into the supply lines 40, here arranged perpendicular to the line axis A-A', and at least one pump 44, configured to convey the fluid to be treated through the distribution manifold 42, then through the supply lines 40 to the internal volume 16.

[0063] According to the invention, the fluid distribution system 18 further comprises for each supply pipe 40, a fluid deflector 46 positioned between the bottom 32 and the supply pipe 40, the fluid deflector 46 having a corrugated surface 48 oriented in a direction secant with the pipe axis A-A', preferably in a direction substantially perpendicular with the pipe axis A-A'.

[0064] In this example, the fluid distribution system 18 includes at least one supply line 40A for the fluid to be treated, and at least one additional supply line 40B for the fluid to be treated, adjacent and advantageously parallel to the supply line 40A. It generally includes more than two parallel supply lines 40, 40A, 40B, in particular between 2 and 50 parallel supply lines 40, 40A, 40B forming a comb.

[0065] Adjacent supply pipes 40A and 40B are separated from each other by a distance of at least 0.5 m, and in particular between 0.5 m and 5 m, measured perpendicularly to the axis of pipe A-A'. Adjacent supply pipes 40A and 40B extend opposite each other, preferably at the same height. They extend above the bottom 32, but away from it. The height separating the lowest point of each supply pipe 40A and 40B from the bottom 32 is generally greater than 5 cm, and is in particular between 5 cm and 80 cm.

[0066] Each supply line 40A, 40B has at least two injection openings for the fluid to be treated 50A, 50B separated longitudinally along the line axis A-A'. Generally, each supply line 40A, 40B includes more than ten injection openings for the fluid to be treated 50A, 50B, distributed along the supply line 40A, 40B from its end connected to the distribution manifold 42 to its free end.

[0067] In an illustrative but not limiting example, shown in Figure 5, the supply line 40A defines successive groups 52A of closely spaced fluid injection openings 50A, the groups 52A being spaced apart from each other along the line axis A-A' by defining intermediate spaces 54A.

[0068] Each group 52A comprises at least two adjacent 50A fluid injection openings, located at a distance from each other that is less than the distance separating along the A-A' pipe axis the two nearest 50A fluid injection openings of two adjacent groups 52A.

[0069] In this example, the additional conduit 40B also includes additional groups 52B of additional openings for injecting fluid to be treated 50B closely spaced, spaced along the conduit axis A-A' and additional intermediate spaces 54B between the additional groups 52B.

[0070] Preferably, the treatment fluid injection openings 50A of the supply line 40A are spaced longitudinally along the line axis A-A' relative to the additional treatment fluid injection openings 50B of the additional line 40B. This prevents the treatment fluid jets produced at the outlet of the treatment fluid injection openings 50A from colliding with the treatment fluid jets produced at the outlet of the additional treatment fluid injection openings 50B, thus preventing an acceleration effect of the treatment fluid between the adjacent supply lines 40A and 40B.

[0071] Preferably, in this configuration, the groups 52A of fluid injection openings to be treated 50A of the supply line 40A are themselves longitudinally offset from the additional groups 52B of additional fluid injection openings to be treated 50B of the additional supply line 40B.

[0072] Thus, each group 52A of fluid injection openings 50A of the supply line 40A is located opposite an additional intermediate space 54B on the additional supply line 40B. Similarly, each additional group 52B of additional fluid injection openings 50B of the additional supply line 40B is located opposite an intermediate space 54A on the supply line 40A.

[0073] Furthermore, at least one section 56A of the supply line 40A without openings for injecting the fluid to be treated 50A is located opposite a section 56B of the additional supply line 40B also without additional openings for injecting the fluid to be treated 50B.

[0074] Other positioning configurations of fluid injection openings to be treated 50A, 50B, fluid injection groups 52A, 52A and intermediate spaces 54A, 54A can be used as alternatives, some examples of configurations being described below.

[0075] With reference to figure 8, the fluid injection openings to be treated 50 are directed towards the bottom 32.

[0076] In example (a) shown in Figure 8, the fluid injection opening 50 opens vertically along a vertical axis B-B' intersecting the central axis of the pipe A-A'. In example (b) shown in Figure 8, the fluid injection opening 50 opens at an angle to a vertical axis B-B' passing through the axis of the pipe A-A', the angle of inclination generally being between 5° and 60°, preferably between 5° and 35°.

[0077] In this case, at least one fluid injection opening to be treated 50 is located on one side of a median plane passing through the pipe axis A-A' and through the vertical axis B-B'.

[0078] In example (c) of figure 8, two fluid injection openings to be treated 50 are located on either side of the median plane passing through the pipe axis A-A' and through the vertical axis B-B', being directed respectively towards additional supply pipes, on either side of the supply pipe 40.

[0079] Each fluid injection opening 50 has an area less than the area of ​​a cross-section of the supply pipe 40, in particular between 0.2 and 0.6 times the area of ​​the internal cross-section of the supply pipe 40.

[0080] For example, the area of ​​each fluid injection opening to be treated 50 is between 2 cm 2 and 300 cm 2 .

[0081] With reference to figures 2 and 9, this notably allows the generation of jets 58 of fluid to be treated 12 at the outlet of each supply pipe 40.

[0082] The jets 58 are initially directed along the axis defined by the fluid injection opening to be treated 50, then are deflected by the fluid deflector 46 presenting the corrugated surface 48, as will be described below.

[0083] The fluid deflector 46 associated with each supply pipe 40 is illustrated in more detail in Figure 3 and Figure 4. The fluid deflector 46 is for example formed on the bottom 32, or applied to the bottom 32, for example in the form of a slab or a plate.

[0084] Each fluid deflector 46 extends along the axis of the pipe A-A' at least opposite the fluid injection openings to be treated 50. It preferably extends over at least 90% of the length of the supply pipe 40, preferably over at least 100% of the length of the supply pipe 40.

[0085] Moreover, as illustrated in Figure 5, when projected onto a horizontal plane, the width of the fluid deflector 46 and its corrugated surface 48 is greater than 50% of the width of the supply pipe 40, in particular is between 50% and 300% of the width of the supply pipe 40. For example, the width of the fluid deflector 46 and its corrugated surface 48 is greater than the width of the supply pipe 40.

[0086] Each fluid deflector 46 comprises a plurality of successive bumps 70 and hollows 72, each hollow 72 being defined between two adjacent bumps 70, with the hollows 72 and the bumps 70 extending at least partly in a direction secant with the pipe axis A-A' projected into a horizontal plane.

[0087] In the example shown in figures 3 and 5, the bumps 70 and the hollows 72 extend over the entire width of the fluid deflector 46, perpendicular to the pipe axis A-A'.

[0088] The bumps 70 and the hollows 72 thus define a plurality of adjacent fluid guidance channels. The adjacent channels define a fluid guidance region located opposite the injection openings 50, 50A, 50B.

[0089] In this example, the adjacent channels all extend parallel to each other and perpendicular to the A-A' conduit axis.

[0090] In the example in Figure 3 and in example (a) shown in Figure 4, the bumps 70 and the hollows 72 have a sinusoidal profile, taken in section along a median axial plane passing through the pipe axis A-A' and through a vertical axis B-B'.

[0091] In example (b) of Figure 4, the bumps 70 and the hollows 72 have a trapezoidal profile. A base 74 of the trapezoid forming the bumps 70 has a length along the duct axis A-A' greater than the length along the duct axis A-A' of the apex 76 of the trapezoid forming the bumps 70. Such a configuration is simple to manufacture by molding.

[0092] In example (c) of figure 4, the bumps 70 have a profile in the shape of an inverted parabola, the hollows having a flat bottom 80. Alternatively, the bumps 70 have a profile in the shape of a semicircle, the hollows having a flat bottom. In example (d), taken in section along a median axial plane passing through the duct axis A-A' and through a vertical axis B-B', the bumps 70 have a profile in the shape of vertically extending teeth, the teeth defining the hollows 72 between them.

[0093] The teeth are preferably defined each by two parallel vertical surfaces 81 A, 81 B, the vertical surfaces 81 A, 81 B being connected to each other by a top surface or edge 81 C. The teeth advantageously have a width, taken between the vertical surfaces 81 A, 81 B, less than at least 5 times their height.

[0094] The teeth are advantageously parallel to each other and thus define a comb.

[0095] In all these examples, the distance D1 separating two successive bumps 70 on the corrugated surface 48 along the pipe axis A-A' is greater than 0.5 times the distance between two successive fluid injection openings 50 along the pipe axis A-A'.

[0096] The height H1 separating a highest point of a bump 70 and a lowest point of an adjacent hollow 72, taken perpendicular to the pipe axis A-A', vertically on the corrugated surface 48 is greater than 0.5 times the maximum axial extent EAM of each fluid injection opening to be treated 50 along the pipe axis A-A' and advantageously between 0.75 times and 4 times the maximum axial extent of each fluid injection opening to be treated 50 along the pipe axis A-A'.

[0097] The hollows 72 open transversely at their transverse ends, on either side of the A-A' conduit axis.

[0098] In the example shown in the figures, the hollows 72 and the bumps 70 have a constant profile across the entire width of the fluid deflector 46, taken perpendicular to the pipe axis A-A'. Alternatively, this profile is not constant across the entire width of the fluid deflector 46, taken perpendicular to the pipe axis A-A'.

[0099] The tops of the bumps 70 are also arranged vertically away from the lowest point of the supply pipes 40.

[0100] Thanks to the presence of the troughs 72 and the bumps 70, the jets 58 produced at the outlet of the fluid injection openings 50, which collide with the corrugated surface 48, are redirected by the corrugated surface 48 along a direction secant to the axis of the conduit A-A', here in a direction perpendicular to the axis of the conduit A-A'. This homogenizes the flow of the fluid to be treated 12 between the adjacent supply conduits 40A, 40B, preventing interactions between the jets coming from the opposite supply conduits 40A, 40B. Consequently, the flow rising vertically in the internal volume 16 of the cell 14 is also more homogeneous, producing a piston effect.With reference to Figure 1, the aeration system 20 includes, for example, a plurality of supply lines 88 for supplying oxygen-containing gas, for example air or pure oxygen, to the bottom of the cell 14, and a plurality of nozzles (not shown) for distributing oxygen-containing gas into the internal volume 16. It also includes a valve 90 for controlling the injection of oxygen-containing gas into the internal volume 16.

[0101] In an example where the level of fluid to be treated 12 is kept constant in the biological treatment reactor, by simultaneously carrying out the steps of supplying fluid to be treated and of removing treated fluid, the treated fluid outlet system 22 is fixedly mounted in the vicinity of the top of the cell 14. It includes, for example, a treated fluid collection system (not shown), for example a chute, opening out of the cell 14 through at least one treated fluid discharge port 92.

[0102] Alternatively, the treated fluid outlet system 22 includes a movable inlet mounted in the internal volume 16, on the surface of the fluid contained in the internal volume 16, to accommodate variations in the volume of the fluid to be treated 12 contained in the cell 14.

[0103] In the example illustrated in Figure 1, the settled solids outlet system 23 is arranged in an intermediate part of the cell 14, above the fluid distribution system 18 and below the treated fluid outlet system 22 and above the air supply lines 88. It includes at least one outlet 94 for settled solids (in particular sludge) and at least one valve (not shown) for controlling the opening and / or closing of the outlet 94 for settled solids.

[0104] Alternatively, the sedimented solids outlet system 23 is arranged under the fluid distribution system 18.

[0105] The sensor system 24 includes, for example, at least one ammonium concentration sensor, and / or at least one nitrite concentration sensor, and / or at least one nitrate concentration sensor, and / or at least one sensor for measuring the concentration of suspended solids in the fluid present in the internal volume 16, and / or a pH sensor, and / or a dissolved oxygen sensor. All sensors are connected to the control unit 26.

[0106] The control unit 26 generally includes at least one processor and at least one memory containing software modules configured to be executed by the processor to perform functions.

[0107] It is configured to allow the execution of the different stages of the process of treating the flow to be treated 12 which will be described below, in particular by selectively controlling at least the pump 44 of the fluid distribution system 18, the pilot valve 90 of the aeration system 20, and the control valve for the opening and closing of the outlet orifice 94, on the basis of instructions given by an operator and / or measurements received from the sensors of the sensor system 24.

[0108] A biological treatment process for a fluid to be treated 12 in the biological treatment reactor 10 according to the invention will now be described.

[0109] The process comprises a plurality of biological treatment cycles which are repeated successively one after the other, each cycle comprising the successive stages of a cycle which are illustrated in Figures 1 and 10.

[0110] At step 100 of each cycle, the control unit 26 activates the pump 44 to bring the fluid to be treated 12 into the internal volume 16.

[0111] The fluid to be treated 12 passes through the distribution manifold 42 and then flows through the supply lines 40. The velocity of the fluid to be treated in each supply line 40 is, for example, greater than 0.1 m / s and is in particular between 0.15 m / s and 2 m / s.

[0112] The fluid to be treated 12 is then injected into the internal volume 16 via the fluid injection openings 50, forming jets 58.

[0113] With reference to example (a) illustrated in figure 9, the jets 58 are directed towards the corrugated surface 48 of the fluid deflector 46, and are therefore reoriented laterally on either side of the conduit axis A-A', possibly towards an additional supply conduit 40B adjacent to the supply conduit 40A.

[0114] Given the tiered distribution of groups 52A, 52B of fluid injection openings to be treated 50A, 50B along respectively the supply line 40A and the additional supply line 40B located opposite the supply line 40A, the jets 58 from the supply lines 40A, 40B redirected by the fluid deflector 46 do not collide with each other and are distributed transversely to the line axis A-A' along the intermediate space between the supply line 40A and the additional supply line 40B.

[0115] This distribution is to be compared with that of the prior art (b) shown in Figure 9, in the absence of a fluid deflector 46 comprising a corrugated surface 48. In the prior art, the jets 58 produced at the outlet of each fluid injection opening to be treated 50A, 50B and deflected by the bottom 32 collide with each other and concentrate axially in the direction of the fluid to be treated circulating in each supply line 40A, 40B between the end connected to the distribution manifold 42 and the free end.On the contrary, thanks to the use of a fluid deflector 46 having a corrugated surface 48 along an axis secant to the axis of the pipe A-A', in particular perpendicular to the axis of the pipe A-A', the natural tendency of the jets 58 to collide is neutralized, and the jets 58 orient themselves precisely, allowing the jets 58 coming from the supply pipe 40A and directed towards the additional supply pipe 40B to interlock with the jets 58 coming from the additional supply pipe 40B and directed towards the supply pipe 40A.

[0116] Thus, an ordered orientation of the jets 58 is obtained, and a very homogeneous velocity field is achieved on the bottom 32 between the supply pipes 40A, 40B, thereby generating a homogeneous upward flow. A gradual ascent of the fluid to be treated 12 within the internal volume 16 is achieved, minimizing local velocity peaks and maximizing the piston effect.

[0117] When a given volume of the fluid to be treated 12 has been introduced into the internal volume 16 of the cell 14, for example, between 1% and 50%, advantageously between 5% and 35%, of the fluid contained in the internal volume 16 before step 100, an aeration step 102 of the fluid to be treated 12 is implemented. Optionally, a non-aeration step (anaerobic and / or anoxic) is implemented before the aeration step 102.

[0118] The control unit 26 activates the air supply pilot valve 90 of the aeration system 20 to inject oxygen-containing gas into the internal volume 16, producing bubbles of oxygen-containing gas into the fluid to be treated 12.

[0119] In the presence of oxygen, a total or partial oxidation of the carbon and nitrogen fractions occurs, into nitrites and / or nitrates for the latter.

[0120] This oxidation step can end on time set (time delay) or on reaching a given setpoint for one or more of the parameters measured by the sensor system 24 and monitored by the control unit 26, for example an ammonium concentration of less than 5 mg N / L.

[0121] Optionally, the fluid to be treated 12 is maintained in anoxia, causing the production of nitrogen gas by denitrification reaction (or denitrification where appropriate) of nitrate and / or nitrite ions.

[0122] At step 106, a settling of suspended solids is carried out to form the treated fluid on the surface and of the solids that have settled under the treated fluid 13.

[0123] At step 108, an outlet of the treated fluid 13 is carried out, preferably simultaneously with the inlet step 100 carried out in the following cycle to advantageously maintain constant the volume of fluid to be treated 12 in the internal volume 16. Furthermore, if necessary, and at any time in the succession of the aforementioned steps, the control unit 26 opens the outlet port 94 to evacuate excess solid matter.

[0124] Thanks to the invention just described, it is therefore possible to have a biological treatment reactor 10 for a fluid to be treated 12 which operates very efficiently with improved performance, by implementing a homogenization of the fluid to be treated 12 introduced into the bottom 32 of the cell 14 of the biological treatment reactor 10. The presence of a fluid deflector 46 having a corrugated surface 48 avoids localized velocity peaks of the fluid to be treated 12, while ensuring a velocity field that is as homogeneous as possible.

[0125] The fluid deflector 46 has a simple design, is easy to manufacture and install, and requires minimal maintenance. This deflector 46 is compatible with all types of biological treatment reactors 10, regardless of their geometry or configuration.

[0126] The fluid deflector 46 maintains homogeneous velocity fields regardless of the nature of the fluid being treated, including clear water, loaded water, and water containing fibers.

[0127] In the variant illustrated in Figure 6, the groups 52A, 52B of fluid injection openings 50A, 50B comprise more than three closely spaced fluid injection openings 50A, 50B, in particular more than five closely spaced fluid injection openings 50A, 50B, notably between six and ten closely spaced fluid injection openings 50A, 50B. This produces a jet curtain 58 directed transversely with respect to the supply line 40A, 40B.

[0128] In the variant illustrated by figure 7, the supply pipe 40A defines for each group 52A, fluid injection openings to be treated 50A which are located on one side of a median plane of the pipe 40A passing through the pipe axis A-A' and fluid injection openings to be treated 50A located on a second side of the median plane, being here axially offset.

[0129] Thus, group 52A is configured to generate at least one jet 58 of fluid to be treated directed to one side of the supply pipe 40A and at least another jet 58 directed to a second side of the supply pipe 40A.

[0130] In an alternative design, not shown, the bumps 70 and troughs 72 of the corrugated surface each have a chevron shape when projected onto a horizontal plane. Also projected onto the horizontal plane, the successive chevrons advantageously have points located on the axis of the conduit A-A'. In another alternative design, shown in Figure 11, the treatment reactor 10 is a pulsed sludge bed clarifier. Upstream of the tank 30, it includes a vacuum chamber 250 defining an internal volume that forms the upstream collector 42.

[0131] The vacuum bell 250 is equipped with a vacuum machine 252, configured to sequentially perform an aspiration of the fluid to be treated, here water, so that the water level in the vacuum bell 250 is higher than the water level in the internal volume 16 of the capacity 30.

[0132] The vacuum bell 250 is connected to a plurality of supply lines 40, each equipped with fluid injection openings 50 opening towards the bottom 32 of the capacity 30. As before, the fluid distribution system 18 further includes for each supply line 40, a fluid deflector 46 positioned between the bottom 32 and the supply line 40, the fluid deflector 46 having a corrugated surface 48 oriented transversely with respect to the line axis A-A'.

[0133] A sludge bed 254 is present above the supply pipes 40, being confined by at least one intermediate partition 256 externally defining a concentrator 258.

[0134] The treatment reactor 10 advantageously comprises on the surface lamellar modules 260 and at least one chute 262 for collecting treated fluid, opening out of the treatment reactor 10 through at least one treated fluid discharge orifice, not visible in Figure 11.

[0135] Generally, the 260 lamellar modules define channels with a hexagonal cross-section, here represented by inclined hatching.

[0136] In operation, the fluid, advantageously pre-coagulated, arrives through the supply pipes 40 and is deflected towards the sludge bed 254 by means of each deflector 46 equipped with a corrugated surface 48, to emerge treated at the level of the chutes 262.

[0137] The sludge bed 254 is kept expanding by means of a pulsating operation involving a plurality of successive cycles. For this purpose, in each cycle, the bell 250 is depressurized by pumping the air it contains through the machine 252, which gradually raises the level of the fluid to be treated 12 in the upstream collector 42, until it reaches a height greater than the fluid surface in the internal volume 16, for example, from 0.6 m to 1 m above the surface. During this phase, the sludge bed 254 settles under the action of gravity.

[0138] When a high level is reached in the bell 250, a vacuum breaker valve is opened. The fluid to be treated 12 then flows through the supply lines 40, acting like a flush. The sludge bed 254 expands. Excess sludge (impurities and reagents) is discharged into the concentrators 256 from where it is extracted at regular intervals.

[0139] Alternatively, the treatment is a chemical treatment of the water to be treated, such as chlorination or ozonation.

[0140] In a variant of each of the preceding embodiments, the fluid deflector or each fluid deflector 46, positioned between the bottom 32 and the fluid injection openings to be treated 50, 50A, 50B, is formed by a plurality of successive disjoint studs projecting onto the bottom 32, spaced apart from each other in pairs as they move along the conduit axis A-A'.

[0141] The disjoint pads extend preferentially parallel to each other under the supply pipe 40, 40A, 40B in a direction secant to the pipe axis A-A', for example perpendicular to the pipe axis A-A'.

[0142] The posts are preferably elongated. They have a first dimension, taken parallel to the secant direction, greater than a second dimension, taken parallel to the driving axis A-A'.

[0143] The successive blocks thus define a succession of bumps 70 and hollows 72, the hollows 72 being delimited downwards by the bottom 32 between the successive blocks, defining the undulating surface 48.

[0144] According to the definition given in the Petit Larousse dictionary, a "capacity" is generally an enclosure delimiting a determined volume, in which a process takes place, here a contacting of the pressurized liquid containing dissolved gas with a fluid to be treated.

Claims

DEMANDS 1. Treatment reactor (10) for a fluid to be treated, in particular a biological treatment reactor, in particular a sequential one, comprising: - a cell (14) having a base (32), the cell (14) defining an internal volume (16) for receiving and treating the fluid to be treated, - at least one supply line (40, 40A, 40B) of the fluid to be treated in the internal volume (16), the supply line (40, 40A, 40B) extending at least partly into the cell (14) opposite the bottom (32) along a pipe axis (A-A'), the supply line (40, 40A, 40B) having at least two injection openings of the fluid to be treated (50, 50A, 50B) into the cell (14) opening towards the bottom (32) spaced along the pipe axis (A-A'), - an outlet system (22) for treated fluid obtained after treatment, characterized by at least one fluid deflector (46) positioned between the bottom (32) and the fluid injection openings to be treated (50, 50A, 50B), the fluid deflector (46) having a corrugated surface (48) having a succession of bumps (70) and hollows (72) defined between the bumps (70), the corrugated surface (48) being placed opposite the fluid injection openings to be treated (50, 50A, 50B), with the hollows (72) and the bumps (70) extending at least partly in a direction secant with the pipe axis (A-A') projected into a horizontal plane.

2. Processing reactor (10) according to claim 1, in which the hollows (72) and the bumps (70) extend transversely with respect to the driving axis (A-A'), preferably perpendicular to the driving axis (A-A').

3. Processing reactor (10) according to claim 1 or 2, wherein the distance (D1) separating two successive bumps (70) on the corrugated surface (48) along the conduit axis (A-A') is greater than 0.5 times the distance between two successive fluid injection openings along the conduit axis (A-A').

4. Treatment reactor (10) according to any one of the preceding claims, wherein the height (H1) separating a highest point of a bump (70) and a lowest point of an adjacent hollow (72), taken perpendicular to the conduit axis (A-A') on the corrugated surface (48) is greater than 0.5 times the maximum axial extent (EAM) of the fluid injection openings to be treated (50, 50A, 50B) along the conduit axis (A-A') and is advantageously between 0.75 times and 4 times the maximum axial extent of the fluid injection openings to be treated (50, 50A, 50B) along the conduit axis (A-A').

5. Processing reactor (10) according to any one of the preceding claims, wherein the bumps (70) have a sinusoidal profile, a polygonal profile, in particular trapezoidal, a comb-shaped profile, or a bell-shaped profile, in section in a vertical plane containing the duct axis (A-A').

6. Treatment reactor (10) according to any one of the preceding claims, wherein in projection onto the horizontal plane, the maximum width of the supply pipe (40, 40A, 40B) is less than or equal to the maximum width of the corrugated surface (48), taken perpendicular to the pipe axis (A-A'), the width of the corrugated surface (48) being advantageously less than three times the maximum width of the supply pipe (40, 40A, 40B).

7. Treatment reactor (10) according to any one of the preceding claims, wherein the fluid deflector (46) is brought onto the bottom (32), in particular in the form of slabs or plates having the corrugated surface (48), or in the form of successive disjoint pads arranged apart from each other two by two moving along the conduit axis (A-A').

8. A treatment reactor (10) according to any one of the preceding claims, comprising at least one additional supply line (40B) for the fluid to be treated extending along the supply line (40A), preferably parallel to the supply line (40A), the additional supply line (40B) having at least two additional injection openings for the fluid to be treated (50B) into the cell (14) opening towards the bottom (32) and being spaced along the axis of the line (A-A'), the biological treatment reactor (10) comprising an additional fluid deflector (46) positioned between the bottom (32) and the additional injection openings for the fluid to be treated (50B), the additional fluid deflector (46) having a corrugated surface (48) having a succession of bumps (70) and troughs (72) defined between the bumps (70), the corrugated surface (48) being positioned opposite the additional fluid injection openings (50B),with the hollows (72) and the bumps (70) extending in a direction secant to the axis of conduction (A-A'), projected onto the horizontal plane.

9. Treatment reactor (10) according to claim 8, wherein the treatment fluid injection openings (50A) of the supply line (40A) and the additional treatment fluid injection openings (50B) of the additional supply line (40B) are offset from each other along the line axis (A-A'), no treatment fluid injection opening (50A) of the supply line (40A) being placed opposite an additional treatment fluid injection opening (50B) along the line axis (A-A').

10. Treatment reactor (10) according to claim 8 or 9, wherein the supply line (40A) has at least two groups (52A) of at least two closely spaced openings for injecting the fluid to be treated (50A) into the cell (14), the two groups (52A) of closely spaced openings for injecting the fluid to be treated (50A) being spaced apart along the line axis (A-A'), the additional supply line (40B) having at least two additional groups (52B) of at least two additional closely spaced openings for injecting the fluid to be treated (50B) into the cell (14), the two additional groups (52B) of additional closely spaced openings being spaced apart along the line axis (A-A').

11. Processing reactor (10) according to claim 10, wherein the groups (52A) of closely spaced apertures are axially offset with respect to the additional groups (52B) of closely spaced apertures.

12. Treatment reactor (10) according to any one of claims 8 to 11, wherein the supply line (40A) defines treatment fluid injection openings (50A) transversely offset from the line axis (A-A'), on the side of the line axis (A-A') directed towards the additional supply line (50B), and treatment fluid injection openings (50A) transversely offset from the line axis (A-A'), on the side of the line axis (A-A') opposite the additional supply line (40B), the treatment fluid injection openings (50A) on the side of the line axis (A-A') opposite the additional supply line (40B) being advantageously offset axially with respect to the treatment fluid injection openings (50A) on the line axis side. (A-A') directed to the additional supply line (40B).22 13. Treatment reactor (10) according to any one of the preceding claims, comprising an aeration system (20) for the fluid to be treated in the internal volume (16).

14. A method for treating a fluid to be treated, comprising the following steps: - introducing the fluid to be treated into the internal volume (16) of a cell (14) of a treatment reactor (10) according to any one of the preceding claims through the fluid injection openings (50A, 50B) of at least one supply line (40, 40A, 40B), the corrugated surface (48) of the fluid deflector (46) directing the fluid to be treated in a direction secant to the line axis (A-A') projected onto a horizontal plane, - treatment of the fluid to be treated in the internal volume (16) of the cell (14), - outlet of the treated fluid by the outlet system (22).

15. Method according to claim 14, wherein the fluid to be treated injected through each fluid injection opening (50A, 50B) forms a jet (58), the jet (58) being oriented by the corrugated surface (48) of the fluid deflector (46) in a direction secant with respect to the conduit axis (A-A') projected into a horizontal plane.

16. A method according to claim 15, wherein the treatment reactor (10) comprises at least one additional supply line (40B) for the fluid to be treated extending along the supply line (40A), preferably parallel to the supply line (40A), the additional supply line (40B) having at least two additional injection openings for the fluid to be treated (50B) into the cell (14) opening towards the bottom (32) and being spaced along the axis of the line (A-A'), the treatment reactor (10) comprising an additional fluid deflector (46) positioned between the bottom (32) and the additional injection openings for the fluid to be treated (50B), the additional fluid deflector (46) having a corrugated surface (48) having a succession of bumps (70) and troughs (72) defined between the bumps (70), the corrugated surface (48) being positioned opposite the additional fluid injection openings (50B),with the hollows (72) and the bumps (70) extending in the secant direction with respect to the conduit axis (A-A'), the process comprising the additional supply of fluid to be treated into the internal volume (16) through the additional fluid injection openings (50B) of the additional supply conduit (40B), the fluid to be treated injected through each additional fluid injection opening (40B) forming a 23, additional jet (58) directed towards the fluid supply line (40A), the additional jet (58) being oriented in the secant direction relative to the line axis (A-A') by the corrugated surface (48) of the fluid deflector (46), each additional jet (58) being emitted between jets (58) emitted towards the additional supply line (40B) by the fluid injection openings to be treated (50A) of the fluid supply line (40A).

17. A treatment process according to any one of claims 14 to 16, wherein the treatment step includes a substep of settling solid matter towards the bottom (32) of the cell (14) to form a treated fluid, advantageously a clarified fluid, towards the surface, the process preferably comprising successive cycles, each cycle comprising the steps of supplying the fluid to be treated, treating the fluid to be treated and removing the treated fluid, the removal of the treated fluid being advantageously carried out simultaneously with the supply of the fluid to be treated for the next cycle.

18. A process according to claim 17, wherein the treatment step comprises, before the settling substep or substeps, a substep of aerating the fluid to be treated using an aeration system (20) to inject a gas containing oxygen into the cell (14), advantageously to generate oxidation of a carbonaceous fraction and / or a nitrogenous fraction present in the fluid to be treated, and a substep of interrupting the aeration of the fluid to be treated, advantageously to place the fluid to be treated in anoxia.

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