Collection container for in-situ sampling device for liquid effluent

Abstract

The invention relates to a collection container (1) for a device for taking samples in situ of a liquid effluent, comprising a generally rectangular parallelepipedal tank (100) delimited by an upper wall (110) having an opening (111) for collecting the sampled effluent, a lower bottom wall (120), a front wall (130), a rear wall (140) and two side walls, said container (1) also comprising a flow tap (200) fluidly connected to an orifice (131) provided in the lower part of said front wall (130) of the tank (100); characterized in that said lower bottom wall (120) has a portion (120A) inclined longitudinally along a slope having a predetermined angle of inclination (θ). Figure to be published with the abstract: Fig. 2

Description

Title of the invention: Collection container for in-situ sampling device for liquid effluent Technical field

[0001] The present invention relates generally to devices for taking samples in situ of a liquid effluent intended to allow them to be analyzed in a laboratory in order to determine the content of certain pollutants in this effluent. The invention relates in particular to a sampling container for such a sampling device. Prior art

[0002] Industries and urban areas discharge effluents (waste water) whose characteristics in terms of flow rates and pollutant concentrations vary greatly over time.

[0003] Current standards for environmental preservation, particularly anti-pollution standards, now require rigorous analyses of such effluents to be carried out according to various physicochemical criteria or parameters imposed by legislation, such as, by way of non-limiting examples, nitrate-nitrite and phosphate analysis, ammonium analysis, silicate analysis, chemical oxygen demand analysis (also known by the abbreviation COD), biochemical oxygen demand analysis (also known by the abbreviation BOD), determination of the concentration of suspended matter, etc.

[0004] To determine the pollutant flows emitted during a period, for example twenty-four hours, elementary samples of these effluents are taken, generally using automatic refrigerated and isothermal sampling devices.

[0005] Such a sampling device is conventionally composed of a suction pipe immersed in the effluent to be sampled, as well as an enclosure containing a vacuum or peristaltic pump, a control module and at least one collection container.

[0006] These elementary samples, taken as a function of time, flow rate or volume elapsed, are grouped in an appropriate manner to constitute a representative average sample contained in the at least said collection container.

[0007] Several fractions of this representative average sample are then transferred from this collection container to analysis bottles intended to be sent to accredited laboratories responsible for determining the concentrations of certain pollutants sought.

[0008] Such a collection container, described for example in French patent application FR 3 069 175 A1 filed by the applicant, conventionally comprises a tank of generally rectangular parallelepiped shape and delimited by an upper wall having an opening allowing the effluent collected to be collected, a lower wall, a front wall, a rear wall and two side walls.

[0009] This collection container also includes a flow tap fluidly connected to the tank via an orifice provided in the lower part of the front wall of this tank and allowing an operator to easily, safely and without risk of contaminating the representative average sample contained in this tank, the operations of transferring fractions of this sample to the various analysis bottles.

[0010] After carrying out these transfer operations during which the entire useful volume (i.e. that located above the valve connection orifice) of the tank is drawn off, the container must be turned over to ensure that it is completely emptied before being replaced in the sampling device so that it can collect a new representative average sample.

[0011] Unfortunately, it turns out in practice that some operators inadvertently forget to completely empty the container before replacing it in the sampling device, so that this liquid residue contained at the bottom of this container will mix with the new representative average sample taken subsequently and thereby distort the results of the analyses carried out subsequently on this last sample. Statement of the invention

[0012] The present invention therefore aims to improve the situation.

[0013] To this end, it proposes a collection container for a device for taking samples in situ of a liquid effluent, comprising a generally rectangular parallelepiped-shaped tank delimited by an upper wall having an opening for collecting the sampled effluent, a lower bottom wall, a front wall, a rear wall and two side walls. The container also comprises a flow tap fluidly connected to an orifice provided in the lower part of said front wall of the tank. According to the invention, said lower bottom wall has a portion inclined longitudinally along a slope having a predetermined angle of inclination.

[0014] The presence of such a longitudinally inclined portion on the lower bottom wall of the reservoir of this container makes it possible to reduce the residual volume of the average representative sample of liquid effluent which cannot be withdrawn via the drain tap because it is located below the level of the connection orifice of this tap.

[0015] Thus, when the operator forgets to turn the container over to empty it completely after the operations of transferring fractions of this representative average sample to different analysis bottles and before replacing it in a sampling device, this reduction in the residual volume contained in the reservoir of the container according to the invention makes it possible to limit the effects of this residual volume on the new representative average sample taken subsequently and collected in this same container.

[0016] Furthermore, the space freed up under this longitudinally inclined portion can be used to house certain additional modules or accessories.

[0017] According to a preferred embodiment characteristic allowing in particular easier use of the freed space without interference with the drain tap, said longitudinally inclined portion advantageously extends downward from said rear wall of the tank over at least the major part of its length.

[0018] In order to further reduce the residual volume of the container, said longitudinally inclined portion may for example extend over the entire length of said tank between its rear and front walls.

[0019] Conversely, and in order to prevent the internal angle of the junction edge between the front and lower walls of the tank from being acute and effluent particles from stagnating there, said longitudinally inclined portion may extend to a horizontal front portion joining said front wall of the tank.

[0020] Still with the aim of optimizing the residual volume of the container without losing useful volume, said predetermined angle of inclination may for example be between 5 and 10° and / or the upper end of this longitudinally inclined portion may be arranged substantially at the same height level as the lower end of said tap connection orifice.

[0021] With the same objective of reducing the residual volume as well as that of improving the homogenization of the representative average sample contained in the tank, said lower bottom wall may have, in cross section, a curved profile whose concavity is turned towards the inside of said tank. This curved profile is advantageously arranged symmetrically with respect to the median vertical longitudinal plane of said tank.

[0022] In order to optimize the capacity of the container in view of the configuration of the dedicated reception housings in the sampling devices, the flow tap is for example housed entirely in a recess provided in the lower part of the front wall of the tank and extending to its lower end.

[0023] In order to ensure better stability of the container, the latter may advantageously include a support base fixed to the lower part of said tank and allowing said container to stand upright when placed on a horizontal support.

[0024] This base may comprise, for example, a rectangular sole extending horizontally under said lower bottom wall of the tank, as well as two lateral fallen edges bordering said sole while extending vertically above the latter and being fixed to said side walls of the tank.

[0025] For reasons of cost and simplicity of manufacture, said holding base is for example made from a cut and folded sheet of metal.

[0026] Still for reasons of cost and simplicity of manufacture, said tank is advantageously molded from a thermoplastic polymer, preferably by a rotational molding process which has the advantage of requiring only a small investment for the manufacture of the molds.

[0027] In order to ensure homogenization of the average representative sample of liquid effluent contained in the tank, the container according to the invention is advantageously provided with an agitator member comprising a rod housed inside said tank and fixedly carrying at its lower end a stirring head capable of generating mixing of the collected liquid.

[0028] In order to ensure in particular better mixing of the average representative sample of effluent contained in the tank, the axis of said rod is advantageously inclined according to a second predetermined angle of inclination with respect to the vertical, preferably between 5 and 30°.

[0029] Still in order to ensure better mixing of the average representative sample of effluent contained in the tank, the axis of this rod is advantageously located in the median vertical longitudinal plane of said tank.

[0030] In order to optimize in particular the capacity of the container in view of the configuration of the dedicated reception housings in the sampling devices, said stirring member also comprises a hub fixedly housed inside said reservoir under its upper wall and receiving the upper portion of said rod in free rotation around its axis, as well as a coupling element fixedly carried by the upper end of said rod and projecting outside said reservoir through a cutout made in its upper wall, this coupling element being provided on its upper face with a coupling relief intended to cooperate by correspondence of shape with that of another coupling element carried by a motorized rotating shaft so as to ensure the rotation of said stirring head.

[0031] The attachment of said hub to said tank is ensured, for example, by means of a plate surmounting said hub to which it is attached, this plate further covering said cutout and being attached to said tank.

[0032] In order to facilitate the emptying of said tank by simply turning the container over, the upper wall of this tank advantageously has a pyramidal shape formed by four inclined sides extending between the peripheral edge of said opening constituting the top of this tank and the upper edges of said front, rear and side walls.

[0033] Finally, and in order to prevent particles of the average sample representative of the effluent from stagnating at the edges and corners of the tank and thus ensure better mixing of this sample, the corners and edges of the tank are advantageously rounded. Brief description of the drawings

[0034] The description of the invention will now be continued by the detailed description of an exemplary embodiment, given below for illustrative but non-limiting purposes, with reference to the appended drawings, in which:

[0035] [Fig.l] represents a perspective view of a collection container according to the invention for a device for taking samples in situ of a liquid effluent;

[0036] [Fig.2] is a sectional view of the container of [Fig.l], taken along its longitudinal plane median vertical; and

[0037] [Fig.3] represents a cross-sectional view of the reservoir included in the can according to the invention, taken along plane III-III of [Fig.2]; and

[0038] [Fig.4] is a perspective view of the coupling element of the agitator member which the container according to the invention comprises. Description of the embodiments

[0039] Figures 1 and 2 illustrate a collection container according to the invention 1, suitable for use in an in-situ sampling device for a liquid effluent, not shown, to collect several elementary samples of this effluent taken as a function of time, flow rate or volume elapsed, so as to constitute a representative average sample of which several fractions will then be transferred from this container 1 to analysis bottles intended to be transmitted to accredited laboratories responsible for determining the concentrations of certain pollutants sought.

[0040] We define with respect to the can 1 an orthogonal reference XYZ comprising three axes perpendicular two by two, namely: - an X axis, defining a longitudinal, horizontal direction, - a Y axis, defining a transverse, horizontal direction, which with the X axis defines a horizontal XY plane, and - a Z axis, defining a vertical direction, perpendicular to the horizontal XY plane.

[0041] In the following description and by convention, the terms “lower” and “upper” will be used to define the relative position of an element with respect to another in the vertical direction, while the terms "front" and "back" will be used to define the relative position of one element with respect to another in the longitudinal direction.

[0042] The collection container 1 comprises a generally rectangular parallelepiped-shaped reservoir 100 whose dimensions are adapted to those of a receiving housing provided on commercial sampling devices, delimited by an upper wall 110 having a circular opening 111 allowing the effluent collected to be collected, a lower bottom wall 120, a front wall 130, a rear wall 140, and two side walls 150, 160.

[0043] The tank 100 is preferably molded from a thermoplastic polymer such as high-density polyethylene (HDPE) or polyvinyl chloride (PVC), optionally reinforced with natural and / or synthetic fibers.

[0044] Essentially for reasons of mold manufacturing cost, the molding process used for manufacturing the tank 100 will preferably be rotational molding, but other processes can also be envisaged, such as in particular extrusion blow molding.

[0045] The collection container 1 also comprises a flow tap 200 fluidly connected to a circular orifice 131 provided in the lower part of the front wall 130 of the tank 100 (see figures 2 and 3) while being advantageously centered with respect to the median vertical longitudinal plane of the latter.

[0046] Made for example from plastic, the flow tap 200 comprises: - a hollow connection base 210 fixed by screwing onto a thread provided on the internal face of the orifice 131; - a withdrawal spout 220 oriented vertically downwards and fluidly connected by an internal distribution circuit to said base 210 (and therefore to the interior of the tank 100); - means for controlling the fluid flow rate (not visible in the figures) acting on the internal distribution circuit to authorize or prevent the circulation of the liquid between the connection base 210 and the withdrawal spout 220; and - a control lever 230 capable of interacting with said control means and being manually actuable by an operator between a rest position in which said control means completely block the circulation of liquid to the withdrawal spout 220, and a flow position in which said control means allow the circulation of liquid to said withdrawal spout 220.

[0047] Advantageously and in order to meet certain regulatory constraints, the internal distribution circuit of the tap has a passage of at least 9 millimeters in diameter.

[0048] According to embodiment variants not shown, the tap can be made of metallic material or metallic alloy such as brass or stainless steel.

[0049] The collection container 1 may also advantageously include a cap or cover, not shown in the figures, capable of being fixedly and removably attached (for example by screwing or clipping) to the opening 111 to close it and so as to allow this container to be moved out of the sampling device without the risk of particles present in the surrounding air (dust, pollen, etc.) being able to penetrate therein and contaminate the representative average sample.

[0050] The upper wall 110 advantageously has a pyramidal conformation formed by four inclined sides 110A, 110B, 110C, 110D extending between the peripheral edge of the opening 111 constituting the top of the reservoir 100 and the upper edges of the front 130, rear 140 and side 150, 160 walls.

[0051] Such a pyramidal conformation of this upper wall 110 allows an operator, after the operations of transferring fractions of the representative average sample to analysis bottles, to carry out by a simple inversion of the container 1 a complete emptying by gravity of the remainder of the liquid remaining therein.

[0052] In order to optimize the capacity of the container 1 in view of the configuration of the dedicated reception housings in the sampling devices, the flow tap 200 is advantageously housed entirely in a recess 132 formed in the lower part of the front wall 130 of the tank 100 and extending to its lower end.

[0053] It will be noted that this recess 132 is delimited laterally and in the upper part by sides having a positive clearance angle so as to facilitate the operations of demolding the tank 100 as well as the manipulation of the control lever 230 of the tap 200.

[0054] As illustrated in [Fig.2], the collection container 1 also comprises an agitator member 300, also commonly referred to as an “impeller”, and capable of generating mixing of the representative average sample to ensure its homogenization before and during each operation of transferring a fraction of this sample to an analysis bottle.

[0055] The agitator member 300 comprises a cylindrical rod 310, housed inside the reservoir 100 and whose axis is advantageously located in the median vertical longitudinal plane of the latter, this rod 310 fixedly carrying at its lower end a stirring head 320 arranged below the level of the connection orifice 131 of the tap 200 near the lower front corner of this reservoir 100.

[0056] The stirring head 320 comprises a support disc 321 extending along a plane perpendicular to the axis of the rod 310 and fixed at its center (for example, by screwing) against the lower end of this rod 310.

[0057] This stirring head 320 also comprises four stirring fins 322 projecting from the lower face of the support disc 321 and extending in radial directions, advantageously being angularly spaced regularly at 90° from each other.

[0058] According to alternative embodiments not shown, the stirring head of the stirring member may be arranged differently and comprise, for example, a different number of stirring fins shaped differently.

[0059] Generally speaking, the profile and arrangement of these stirring fins are defined so as to ensure effective stirring of the representative average sample contained in the tank 100 while avoiding the generation of vortices (the latter causing oxygenation of this sample impacting certain of its physicochemical properties and therefore on the results of certain analyses such as for example the COD and / or the BOD).

[0060] The agitator member 300 also comprises a hub 330 inside which the upper portion of the rod 310 is mounted to rotate freely around its axis by means of one or more ball bearing rings. This hub 330 is fixedly housed inside the tank 100 under the inclined face 110A of its upper wall 110 and passing through a cutout 112 of complementary shape made in this inclined face 110A.

[0061] The hub 330 is fixed to the tank 100 by means of a rectangular plate 340 surmounting this hub 330 to which it is fixed (for example, by screwing), this plate 340 further covering the cutout 112 and being fixed to the tank (for example, by screwing).

[0062] The agitator member 300 finally comprises an annular coupling element 350 fixedly carried by the upper end of the rod 310, for example using a clamping screw screwed into a radial through-threading 351 (see [Fig.4]) provided in this element 350 and the end of which is clamped against this upper end of the rod 310.

[0063] Projecting outside the reservoir 100 through the cutout 112 and a complementary shaped hole made in the plate 340, this coupling element 350 is provided on its upper face with a coupling relief 352 (see [Fig.4]) intended to cooperate by matching shape with that of another coupling element carried by a motorized rotating shaft not shown, so as to ensure the rotation of the stirring head 320.

[0064] Such a motorized rotating shaft may for example be housed in a housing that can be removably attached to the plate 340, this housing also advantageously housing a battery providing the electrical power supply to the shaft as well as a variator making it possible to adjust its rotation speed.

[0065] It will be noted that the axis of the rod 310 corresponding to the axis of rotation of the stirring member 300 is advantageously inclined at a second predetermined angle of inclination a with respect to the vertical, which makes it possible to ensure better mixing of the representative average sample and to prevent the suspended particles contained in this sample and sucked axially then rejected tangentially by the stirring head 320 from being projected towards the connection base 210 of the tap 200 and from being dismantled by the latter.

[0066] This angle of inclination a is advantageously between 5 and 30° and preferably between 10 and 20°.

[0067] As illustrated by [Fig.2], the lower bottom wall 120 of the tank 100 has a longitudinally inclined portion 120A following a slope having a predetermined angle of inclination 0, advantageously between 5 and 10°.

[0068] More precisely, this longitudinally inclined portion 120A extends downwardly from the rear wall 140 of the tank 100 over at least the majority of its length and up to a horizontal front portion 120B joining the front wall 130 of this tank 100.

[0069] The presence of this longitudinally inclined portion 120A makes it possible to reduce the residual volume of the representative average sample which cannot be withdrawn via the drain tap 200 because it is located below the level of the connection orifice 131 of this tap.

[0070] Thus, when the operator forgets to turn the container 1 over to empty it completely after the operations of transferring fractions of the representative average sample to different analysis bottles and before replacing it in a sampling device, this reduction in the residual volume contained in the reservoir 100 makes it possible to limit the effects of this residual volume on the new representative average sample taken subsequently and collected in this container 1.

[0071] Still with reference to [Fig.2] and in order to further optimize this residual volume, the upper end of this longitudinally inclined portion 120A is preferably arranged substantially at the same height level as the lower end of the connection orifice 131 of the tap 200.

[0072] It will also be noted that this longitudinally inclined portion 120A makes it possible to improve the homogenization of this representative average sample during its mixing by the agitator member 300 by “bringing back” the suspended particles close to the bottom of the reservoir 100 towards its front part where the agitator member 300 is located.

[0073] Furthermore, the space freed up under this longitudinally inclined portion 120A can be used advantageously to house certain complementary modules or accessories, such as for example a wireless telecommunications module, not shown, and allowing the container 1 to transmit to the outside certain data representative of the average sample measured by sensors such as for example its temperature or its volume.

[0074] According to alternative embodiments not shown, this longitudinally inclined portion can extend over the entire length of the tank 100 between its rear 140 and front 130 walls.

[0075] As illustrated by [Fig.3] showing only the tank 100, the lower bottom wall 120 advantageously has, in cross section, a curved profile in the shape of an arc of a circle whose concavity is turned towards the inside of the tank 100 and being arranged symmetrically with respect to the median vertical longitudinal plane of this tank 100.

[0076] Such a curved profile of the lower bottom wall 120 also makes it possible to reduce the residual volume of the representative average sample that cannot be withdrawn via the drain tap 200, as well as to improve the homogenization of the representative average sample contained in the reservoir 100 during its mixing by the agitator member 300 by “bringing back” the suspended particles close to the two lateral sides of this reservoir 100 towards its central part where this agitator member 300 is located.

[0077] This curved profile is preferably configured so that the height difference between its center and its lateral ends is between 5 and 15 millimeters.

[0078] It will also be noted that the reservoir 100 advantageously has rounded corners and edges so as to prevent particles of the representative average sample from stagnating there and thus to ensure better mixing of this sample.

[0079] The collection container 1 further comprises a holding base 400 fixed to the lower part of the reservoir 100 and allowing this container to stand vertically when it is placed on a horizontal support such as that of a sampling device or that allowing the operations of transferring fractions of the representative average sample to analysis bottles to be carried out.

[0080] Preferably made from a sheet of metal sheet (advantageously stainless steel) cut and folded, this holding base 400 comprises a rectangular sole 410 extending horizontally under the lower bottom wall 120 of the tank 100 and against its horizontal front portion 120A, as well as two lateral flanged edges 420, 430 bordering the sole 410 while extending vertically above the latter and being fixed to the side walls 150, 160 of the tank 100.

[0081] The fixing of each lateral flanged edge 420, 430 on the corresponding lateral wall 150, 160 of the tank 100 is advantageously ensured by means of at least two screws spaced longitudinally from one another, the rods of which, previously introduced through respective orifices made in this flanged edge, are screwed onto threaded metal inserts 151, 161 integrated into this side wall 150, 160 and visible in particular in [Fig.3] (these inserts being positioned in the mold before injection of the plastic material forming the tank 100).

[0082] The rectangular sole 410, the width and length dimensions of which are identical to those of the reservoir 100, has a notch 411 formed in its front part in line with the recess 132 and the profile of which matches that in horizontal section of the latter.

[0083] Finally, the collection container 1 may also include an inverted U-shaped grip handle, not shown, mounted in an articulated pivoting manner on the top of the tank 100.

[0084] To do this, each of the side walls 150, 160 incorporates at its upper end, a respective threaded metal insert 152, 162 intended to allow the two free ends of the handle to be screwed with free rotation onto these walls 150, 160 (see [Fig.3]).

[0085] Generally speaking, it will be recalled that the present invention is not limited to the embodiments described and shown, but that it encompasses any other variant execution within the reach of those skilled in the art.

[0086] The container according to the invention can also find application in fields other than that concerning the in-situ sampling of a liquid effluent.

Claims

Claims

1. Agitator member (300) for a collection container (1) of a device for taking samples in situ of a liquid effluent comprising: - a cylindrical rod (310), - a stirring head (320) fixedly carried by said cylindrical rod (310) at the lower end of said rod (310) and comprising: i. a support disc (321), having a lower face and an upper face, extending along a plane perpendicular to the axis of said cylindrical rod (310) and fixed at its center against the lower end of said cylindrical rod (310); ii. at least two stirring fins (322) projecting from the lower face of said support disc (321), extending in mirrored radial directions and disjoint from each other and arranged to ensure efficient stirring of said liquid effluent while avoiding the generation of vortices.

2. Stirring member (300), characterized in that the two lateral edges of each stirring fin (322) have a profile in the form of a portion of a parabola and each form, with said lower face of said support disc (321), an angle of inclination whose value decreases progressively between the free lower end of each said stirring fin (322) and said lower face of said support disc (321).

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