EP2804685A1

EP2804685A1 - Device for collecting clarified water

Info

Publication number: EP2804685A1
Application number: EP13700758.9A
Authority: EP
Inventors: Patrick Exposito
Original assignee: Veolia Water Solutions and Technologies Support SAS
Current assignee: Veolia Water Solutions and Technologies Support SAS
Priority date: 2012-01-20
Filing date: 2013-01-21
Publication date: 2014-11-26
Also published as: AU2013210936B2; AU2013210936A1; CA2862121A1; FR2985918B1; FR2985918A1; WO2013107912A1; WO2013107912A9; US20150090644A1

Abstract

A device for collecting clarified water intended to be fitted to a basin (1), said device comprising: • at least one mobile float (3) movable in vertical translation and provided with at least one water collection member (4); • means for collecting and discharging (5) the collected water; • means for guiding said mobile float (3) in vertical translation; • means for securing (7) to said basin; characterised in that a vertical central guide bar (6) is disposed according to the central axis of gravity of said device and extends into said means for collecting and discharging (5).

Description

Clarified water sampling device.

1. Field of the invention

The invention relates to the field of design and implementation of water treatment facilities for their purification or their potabilisation.

More specifically, the invention relates to devices equipping the water treatment tanks for taking surface water clarified to evacuate the basin in question and commonly called weirs.

2. Prior Art

Such weirs are particularly used in wastewater treatment plants using the technique known as SBR (Sequencing Batch Reactor). This technique consists in bringing into contact with a pool a quantity of water with activated sludge, alternating aeration and decantation sequences, and evacuating the clarified water on the surface following the settling phase. During this last phase, the clarified water present on the surface must be collected to be evacuated from the basin which causes a lowering of the water level in the basin. This evacuation operation can be done by pumping, thanks to a pump maintained on the surface of the water by floats. However, to this technique it is preferred, for reasons of energy saving, that of discharging the clarified water basin by gravity flow through weirs provided to stay on the surface of the water with floats .

In order to carry out this operation of evacuation of the clarified water in a gravitational manner, it is known to have weirs equipped with a float allowing them to be held on the surface of the water of the basin and a sampling member. water in which the clarified water falls to be taken up by means of collection and gravity evacuation.

Several types of floating weirs are thus known.

Some consist of a simple funnel placed in a float freely floating on the surface of the water, that is to say without means of guiding the float, the funnel being connected to a drain pipe.

Others, more elaborate, include a rocking float. These devices include a float provided with water withdrawal means and a lever arm connected at one of its ends to the float and connected by the other of its ends to a water outlet. Still others include guide means in vertical translation of the float provided with a water sampling member, the means in question including two lateral guide bars mounted parallel to the axis of vertical displacement of the floating weir, provided by on both sides of the float and attached to the sail of the pool equipped with such a device. Such a sliding floating weir is described in particular in the French patent application FR-A-2873724.

Simple floating weirs without a guide system have limited processing capacity. In addition, their hydraulic behavior being, due to the lack of guidance of the float, completely random, they can be used in a limited number of scenarios, for example de-oiling or evacuation of an overflow in a treatment pond of a station.

The design of the rock weirs implies that their position relative to the wall of the basin varies according to the height of the water in the basin. Their hydraulic behavior is thus variable according to this height of water. This variable hydraulic behavior can lead to the removal of "floating", that is to say supernatants present on the surface of the water and / or that of "sub-swimmers", that is to say materials in suspension present just below the surface of the water. Such samples are of course to be avoided to maintain the quality of the clarified water taken.

In addition, the lever arm equipping such dumping weirs takes up the hydraulic forces absorbed by the surface of the float. As this arm moves with the surface level of the water in the pool, the associated moment increases when the water level drops in it. Since the energy produced by the movement of water in the basin is too large, such overflow weirs are not recommended insofar as their installation could then lead to mechanical deterioration thereof.

The weirs sliding on two lateral guide bars have the disadvantage of requiring on-site installation of the guide bars which must be meticulous since the positioning axis of these guide bars is independent of the sliding axis of the guide bars. float.

In addition, the sliding of the float along these side bars results in a hyper-tatism that can lead to the jamming of the float and therefore in practice the decommissioning of the weir and therefore the need to intervene on site to restore a sliding of the float along the guide bars. Such interventions lead to increased operating costs. Finally, such sliding weirs being attached to the sail of the pool they equip, the position of their float relative to this sail can not be changed after being filled with water. However, when commissioning the weir, it may be that a better orientation of the float in the basin would have optimized the operation of this weir.

Whatever the nature of the floating weir used, the quality of the clarified water actually taken from it must be monitored by regularly measuring different physicochemical parameters of it. In practice, this is done through the use of probes that are brought by an operator at the float using long poles. This operation, which can prove perilous, especially if the water level in the basin is low, can be complicated if the energy dispersed on the surface of the basin is strong. In addition, such a sampling technique, does not ensure a high reproducibility of the measurements made to the extent that the samples can not be made always at the same distance from the float. 3. Objectives of the invention

The object of the invention is notably to overcome these disadvantages of the prior art.

More specifically, an object of the invention is to provide a clarified water sampling device provided with vertical translation guide means involving virtually no risk of jamming the float.

Also an object of the invention is to provide, in at least one embodiment, such a device that allows to greatly limit the removal of floating or underwater.

Yet another object of the invention is to provide, in at least one embodiment of the invention, such a device whose orientation with respect to the veil of the pool can be adjusted after being filled with water.

Another objective of the invention is to propose, in at least one embodiment, such a device provided with means making it possible to optimize the measurement operation by probes of the physicochemical parameters of the clarified water sampled.

Yet another object of the invention is to propose, in at least one embodiment, such a device that can be sized to handle very large water flows.

Another objective of the invention is to propose, in at least one embodiment, such a device whose mounting time on the pool it equips is reduced compared to that required for mounting the devices of the prior art. . Yet another object of the invention is to propose, in at least one embodiment, such a device that can be transported while occupying, with equivalent processing capacity, less volume than the devices of the prior art.

4. Presentation of the invention

These different objectives, as well as others which will appear later, are achieved thanks to the invention which concerns a clarified water sampling device intended to equip a basin, said device comprising:

at least one mobile float in vertical translation provided with at least one water sampling member;

means for collecting and discharging the withdrawn water;

guide means in vertical translation of said mobile float;

means of support and solidarity to said basin;

characterized in that said means for vertically translating said mobile float comprises a vertical central guide bar disposed along the central axis of gravity of said device, said guide bar passing through said float and extending into said collecting means and evacuation.

The invention is therefore based on a completely original approach of providing to slide the float only on a vertical central guide bar provided on the axis of gravity of the device. According to such a configuration, the guide axis of the float and the axis of movement thereof are merged. This configuration makes it possible to eliminate the problems of hyperstatism observed with the flotation devices according to which the float is guided by two lateral guide bars and in which the two guide axes are therefore distinct from the axis of displacement of the float which generates float jamming problems. According to the invention, the guide bar of the device being provided along the central axis of gravity of the device, it does not undergo any effort in situation. The forces experienced by the device are entirely taken up by the support and securing means to the basin. There is therefore virtually no risk of the float jamming on the guide bar.

As a result, the risks of sampling floating matter from the water surfaces or from underwater materials in the vicinity of it are, thanks to the invention, very low because the central guide bar of the float ensures that the float, and thus the means of taking water that equip it, constantly follow the water level in the basin, which was not always the case in the prior art according to which the guidance was provided by two lateral guide bars.

Preferably, said means for collecting and discharging the device according to the invention are telescopic and comprise an upper tube connected to said water sampling member and a lower tube intended to be connected to a water discharge pipe ,.

The assembly constituted by the means of support and attachment to the basin, the guide bar and the lower tube of the collection and evacuation means then constitutes a fixed assembly secured to the basin, while the float equipped with sampling means water and the upper tube of said collection and evacuation means constitute a movable assembly in vertical translation. The various parts constituting the device can advantageously be pre-assembled in the factory so that it can be easily and conveniently brought to the site and quickly mounted in the pool. In addition, the assembly made in the factory makes it possible to give this assembly an excellent degree of precision. Tests may be performed on the device before it is mounted in the pool. Such pre-assembly at the factory of the device according to the invention is particularly appreciable during the first installation of the device. In addition, all the parts of the device being removable, maintenance of the device is facilitated.

According to a preferred aspect of the invention, said means for supporting and securing the basin include a bracket whose horizontal portion is connected to said guide bar and whose vertical portion is intended to be fixed to the web of said basin. This configuration ensures a good recovery of the forces exerted on the device by the bracket that can be firmly fixed to the pool with adequate fastening means.

Note that the horizontal part of the bracket may be directly related to the guide bar or, as will be explained below in more detail, linked thereto via one or more mechanical elements.

According to a preferred aspect, said support and securing means include at least one connecting bar connecting said vertical part of said bracket to said lower tube of said collection and evacuation means. Such a connecting bar reinforces these means of support and solidarity.

Also preferably, said water sampling member is constituted by a chamber provided under said float, said chamber have water inlet orifices intended to be embedded and distributed over all or part of its periphery. The orifices being intended for be drowned, they allow the collection of clarified water free of floating matter and little or no load of underwater materials.

Also preferably said orifices are surmounted by deflectors. Such deflectors prevent the passage of some floating.

According to an advantageous variant of the invention, said chamber has a bottom connected to said collection and evacuation means and inclined chutes to said collection and evacuation means. Thanks to such a configuration, including inclined chutes, the clarified water entering the sampling means is directed to the collection means with a minimized pressure drop. In practice, such chutes allow the acceleration of the water passing through the chamber and the optimization of its evacuation time. The capacity of the device according to the invention is optimized.

The float, as well as the sampling organ that equips it, may have different shapes. However, according to a particularly preferred variant, said float and said sampling member form a substantially parallelepipedal assembly, said float being provided with a vertical central channel accommodating said guide bar. It can thus be provided to provide water inlet orifices of the water sampling member on one, two, three or four faces of this essentially parallelepipedal assembly, depending on the configuration of the basin and depending on the capacity that it will be desired to give the device according to the invention.

According to a particularly advantageous variant of the invention, the device according thereto comprises means for pivoting said float in a horizontal plane. Such pivoting means are particularly interesting for adapting the device to different basin configurations.

Also according to a particularly practical variant of the invention, the device according thereto advantageously comprises a probe support slidably mounted on said horizontal bar and liftable independently of said float. This probe support includes probes that take a small amount of water or measure at least one of its physicochemical parameters. According to the invention, such a support is designed to rest on the float so that the probes associated therewith are in contact with surface water at its sampling by the sampling member. The guide bar of the device then serves as a guide element also for the support of probes. Thus, the use according to the prior art of long rods for bringing such probes to the level of the water taken by the spillway is no longer necessary. The ergonomics of this work is found improved. The raising of the probe support independently of the float can be carried out for example by a set of cables and a pulley. This recovery can be done manually but an engine can also be planned to implement it.

When the device according to the invention is intended to treat large flows of clarified water, the float thereof may be composed of three parts, namely a central portion and two side portions connected to said central portion and provided from and thereafter, each of said portions being provided with a corresponding portion of the clarified water sampling member, the device further including two control valves of said water sampling member. With such valves, it is possible to manage the amount of water taken by the sampling member. Such valves provided downstream of the spillway may replace the automatic valve provided downstream of the spillway on the water outlet pipe discharging water from the basin, and which controls the draining thereof. These valves can let pass quantities of variable water according to a setpoint that will be given to them by an automaton.

In order to facilitate the transport of the mobile part of the device including the float and the sampling member, in particular for its export, said lateral parts of said float are advantageously pivotally mounted on said central portion. The size of the float can be reduced during transport by rotating the side portions so as to fold. During its assembly, the lateral parts can be raised to be put in line with the central part.

5. List of figures

The invention, as well as the various advantages that it presents, will be more easily understood thanks to the following description of four different nonlimiting embodiments thereof given with reference to the drawings in which:

- Figure 1 is a top view of a pool equipped with a clarified water sampling device according to the invention;

FIG. 2 is a perspective view of a first embodiment of a device according to the invention;

FIG. 3 is a front view of the float of the device represented in FIG. 2;

FIG. 4 is a side view of the float of the device represented in FIG. 2;

- Figure 5 is a high perspective view of the float water sampling member of the device shown in Figure 2; - Figure 6 is a top view of the sampling member shown in Figure 3;

- Figures 7 to 10 illustrate different assembly steps of the various elements constituting the device shown in Figure 2;

FIG. 11 is a perspective view of a second embodiment of a device according to the invention including a pivoting float;

- Figures 12 to 14 show top views of the device of Figure 11 illustrating three different positions of the float;

FIG. 15 represents a perspective view of a third embodiment of a device according to the invention including a sliding and liftable probe support;

FIG. 16 represents a perspective view of a fourth embodiment of a device according to the invention for treating large flow rates of water;

- Figure 17 shows a front view of the movable part of the device according to Figure 16 in the transport position;

- Figure 18 shows the deployment of said movable part of the device according to Figure 16 before installation.

6. Description of embodiments of the invention

The four embodiments of the clarified water sampling device 2 are intended, with reference to FIG. 1, to equip a basin 1 for water treatment implemented according to the SBR technique (sequencing batch reactor). However, the device according to the present invention is not limited to the pond equipment implemented according to this technology but may also be installed in basins operating in another mode, however leading to clarified surface water to be evacuated.

The basin 1 shown in Figure 1 has a bottom 101 and a sail 103 circular. It is equipped with aeration means 102 intended to be immersed in the water treatment tank so as to provide the activated sludge which develops therein the oxygen necessary for the degradation of the organic pollution contained in these waters and therefore to the purification of this one.

With reference to FIGS. 2 to 10, a first embodiment of the clarified water sampling device according to the invention will now be described.

This first embodiment comprises a float 3 of substantially parallelepipedal shapes including a block of less dense material than water, such as polystyrene, provided in a protective housing made of a plastic or metal material. This float 3 is equipped at its base with a water sampling member 4 secured to the float 3, the assembly consisting of the float 3 and the sampling member 4 constituting a substantially parallelepipedal assembly.

The water sampling member 4 is provided on its front face with four water inlet orifices 41 each surmounted by a deflector 42. Such deflectors may be fixed or movable when it is desired to reduce the pressure. section of the orifices 41 after commissioning.

The water sampling device 4 is connected to means for collecting the collected telescopic water 5 consisting of an upper tube 51 and a lower tube 52. The lower tube 52 is intended to be connected by a flange. 54 connection to a water outlet pipe discharging the water taken by the spillway out of the basin and provided with an automatic valve (not shown) allowing or not the emptying thereof. A sealing connection 53 is provided between the two tubes 51, 52.

The device further comprises means 7 for supporting and securing to the sail 103 of the basin. These support and securing means comprise a bracket 71 having a horizontal portion 72 and a vertical portion 73. Link bars 74 are provided between the vertical bar 73 of the support and securing means 7 to secure the lower tube 52 means collection of the water taken from the gallows 7 thanks to collars 75.

Finally, the device described also comprises a guide bar 6 which, as will be explained in more detail with reference to the following figures, has an upper end fixed to the end of the horizontal portion 72 of the bracket 71 and whose lower end is left free. In other embodiments, this lower end may be secured by welding to the lower part of the tube 51

According to the invention, the guide bar 6 is arranged along the central axis of gravity of the device. Referring to Figure 3 the float 3 is for this purpose provided with a vertical central recess having a cross section slightly greater than the section of the guide bar 6 and intended to accommodate it.

With reference to FIGS. 5 and 6, the water sampling member associated with the floats 3 comprises a speed-up chamber 44 for the clarified water intended to enter the sampling device via the orifices 41. The bottom 43 of this Chamber 44 is connected to the upper tube 51 of the collection means 5 of the withdrawn water. This bottom 44 is also provided with chutes 441 inclined. The inclination of these chutes reduces the pressure drop experienced by the water entering the upper tube 51.

Referring to Figures 7 to 10, the factory pre-assembly of the various elements of the device before installation in a basin is shown.

In a first step, as shown in FIG. 7, the support and securing means 7 intended to be subsequently attached to the sail of a basin are constituted by assembling the vertical bar 73 and the horizontal bar 72 to form the stem 71. Next, the upper fixing plate 76 and the lower fixing plate 77 are mounted on this bracket and the bars 74 and the collars 75 are put in place.

As indicated in FIG. 8, the lower tube 52 of the collected water collecting means 5 is assembled to the stem by means of the collars 75. A connection flange 54 intended to connect the lower tube 52 to an outlet pipe of FIG. basin water is provided at the base thereof and a sealed connection 53 for organizing the seal with the upper tube of the collection means 5 is then secured to the upper end of the tube 52.

Referring to Figure 9, the vertical guide bar 6 of the float is then slid inside the tube 52 and its upper end is secured to the end of the horizontal portion 72 of the bracket 71 while its lower end is left free at the upper end of the lower tube 52.

The assembly constituted by the float 3 equipped with the sampling member 4 and the upper tube 55 can then be installed as shown in FIG.

With reference to FIG. 2, once installed in the basin, the device described can be implemented at the end of a phase of decantation of a water treatment in SBR mode in order to evacuate the clarified water. surface. For this purpose, the dimensions of the float are provided such that the orifices 41 of the sampling member 4 are permanently embedded just below the surface of the water.

The clarified water is taken by the member 4 and passes through the chamber 44 thereof before being directed towards the collection means 5 to be evacuated. As evacuation of the basin the level of this water falls in it. Due to the telescopic nature of the collection means 5, the float 3 equipped with the sampling member 4 and the tube 51 constituting a mobile part of the device lower with this level in the basin along the axis defined by the bar 6. This lowering can continue to a minimum level in which the upper tube 51 is fully retracted into the lower tube 52. Thanks to the central guide bar 6 provided along the axis of gravity of the device, the float 3 has virtually no risk of getting caught on this bar. This bar 6 also does not take up the vertical / axial forces exerted on this float 3 and this sampling member 4 since this float and this member slide around this bar. This bar 6 also takes up the horizontal / radial forces exerted on this float 3 and this sampling member 4. All these forces are then transmitted to the support and securing means 7 constituted by the bracket 71, via the part horizontal 72 thereof and connecting bars 74.

The device according to the invention is thus simple to install. In addition, the mobile part constituted by the float 3, the sampling member 4 and the upper tube 51 of the collecting means 5 constitute a movable part which can be easily detached from the fixed part constituted by the lower tube 52 and means and support and securing 7 fixed to the veil of the basin. Thus, it is possible to change this mobile part when needed without having to dismantle the entire device attached to the basin. It is also possible to disassemble this moving part to ensure the maintenance of the float and the sampling member if necessary.

With reference to FIGS. 11 to 14, a second embodiment of a clarified water sampling device according to the present invention will now be described. In these figures, the elements common to the first embodiment have the same reference.

According to this second embodiment, the orifices 41 of the sampling member 4 are surmounted by a common deflector 42.

Furthermore, according to this second embodiment, the horizontal portion 72a of the bracket 71 has an end that is not directly connected to the guide bar 6 but connected thereto via an element 8 constituting a pivoting means of the float 3. This element 8 is constituted by a plate having the shape of a disk sector 81 having a pivot axis 83 and an arcuate guide light 82. This pivot axis 43 is connected at the upper end of the guide bar 6 while the horizontal portion 72a of the bracket 71 has an end which is designed to slide in the arcuate guide light 82 of the plate 81. This plate 81 is moreover extended by a rod 84 whose activation, with reference to FIGS. 12 to 14, makes it possible to orient the float 3 at an angular amplitude corresponding to that of the arcuate light 82. Such an orientation of this float 3 makes it possible to adapt the position of the latter to different basin configurations, in particular to avoid the catch of floating or underwatering which can concentrate in certain parts of the basin according to this configuration.

With reference to FIG. 15, a third embodiment of clarified water sampling device according to the invention is described. In this figure, the elements common to the first and / or second embodiment have the same reference.

It will be noted that in FIG. 15 this third embodiment is represented with the float 3 provided with the sampling member 4 at its lowest possible level in the basin, the upper tube 51 means for collecting the water withdrawn 5 being fully retracted into the lower tube 52 of these same means.

According to this third embodiment, the device is equipped with a support 9 supporting probes 91. More specifically this support 9 is constituted by a frame 92 slidably mounted on the central guide bar 6 so as to adapt at least two positions to know :

a first position in which the frame 92 rests on the deflectors 42 fitted to the sampling member 4, and;

- A second position as shown in Figure 15 wherein the frame 92 is raised independently of the float 3 so that the probes 91 can be easily recovered by an operator.

Such a sensor support liftable independently of the float has a significant advantage over the prior art according to which, to measure the parameters relating to the clarified water taken by the sampling member of the float, it had to be called upon. long bulky rods to maneuver and do not always collect at the same distance from the float.

With reference to FIGS. 16 to 18, a fourth embodiment of clarified water sampling device according to the invention is described, this embodiment being intended for the treatment of large flow of clarified water.

According to this embodiment, the float consists of three parts 3a, 3b, 3c, namely a central portion 3a connected to two lateral parts 3b and 3c, the sampling member 4 is itself also constituted of three parts 4a, 4b, and 4c. Only the parts 4b and 4c are provided with orifices 41 of water inlet. According to this fourth embodiment, two valves 10 are provided to open or close the access of the water passing through the orifices 41 to the central portion 4a of the collection member for its evacuation by the collection means 5. According to the desired discharge rate, one or two cylinders can be actuated to double or not the amount of clarified water passing through the device.

As can be understood with reference to FIGS. 17 and 18, the parts 3b and 3c of the float equipped with the corresponding parts 4b and 4c of the sampling member are pivotally mounted on the part 3a of the float so that they can be folded towards the pipe 51. The assembly constituted by the float, the sampling member and the upper tube 51 can thus be transported or stored in a reduced volume.

It will be noted that in the four described embodiments, the water inlet orifices are provided on a single face of the sampling member. However, depending on the basin configurations, it may be envisaged to provide two or three sides of the sampling member of such orifices.

Claims

Clarified water sampling device for equipping a basin (1), said device comprising:

at least one float (3) movable in vertical translation provided with at least one water sampling member (4);

means for collecting and discharging (5) the withdrawn water;

guide means in vertical translation of said mobile float (3);

support and securing means (7) to said basin;

characterized in that a vertical central guide bar (6) is disposed along the central axis of gravity of said device, and extends into said collection and discharge means (5).

Device according to claim 1 characterized in that said collecting and discharging means (5) are telescopic and comprise an upper tube (51) connected to said water sampling member (4) and a lower tube (52).

Device according to any one of the preceding claims characterized in that said support and securing means (7) include a bracket (71) whose horizontal portion (72) is connected to said guide bar (6) and whose part vertical (73) is intended to be fixed to the web (103) of said basin.

Device according to claims 2 and 3 characterized in that said support and securing means (7) include at least one connecting bar (74) connecting said vertical portion (73) of said bracket to said lower tube (52) of said means of collection and evacuation (5).

Device according to any one of the preceding claims, characterized in that said water sampling member (4) is constituted by a chamber (44) provided under said movable float (3), said chamber having inlet openings of water (41) distributed over all or part of its periphery and intended to be drowned.

6. Device according to claim 5 characterized in that said water inlet ports (41) are surmounted by deflectors (42).

7. Device according to claim 5 or 6 characterized in that said chamber (44) has a bottom (43) connected to said collection and discharge means (5) and provided with channels (441) inclined towards said collection means and evacuation (5).

8. Device according to any one of the preceding claims characterized in that said float (3) and said sampling member (4) form a substantially parallelepipedal assembly, said float being provided with a vertical central channel (31) accommodating said bar guide (6).

9. Device according to any one of the preceding claims characterized in that it comprises pivoting means (8) of said float (3) in a horizontal plane.

10. Device according to any one of the preceding claims characterized in that it comprises a support (9) probes slidably mounted on said horizontal bar (6) and lift independently of said float (3).

11. Device according to any one of the preceding claims characterized in that said float (3) is composed of three parts (3a, 3b, 3c), namely a central portion (3a) and two side portions (3b, 3c). connected to said central portion (3a) and provided on either side thereof, each of said portions being provided with a corresponding portion of the clarified water sampling member, and said device further includes two control valves (10) of said water sampling member (4).

12. Device according to claim 11 characterized in that said side portions (3b, 3c) of said float (3) are pivotally mounted on said central portion (3a).