FR2638178A1 - Device for scraping out and removing mud (sludge) which is sedimented on the bottom of a stretch of water - Google Patents

Abstract

Device for scraping out a stretch of water or watercourse, and including: - at least one scoop 6 for sucking up mud (sludge); - a movable support 2 for the said scoop 6, 6'; - a platform 1 mounted on buoyancy means 19, 19' and including means 21, 23 for moving over the surface of the liquid medium to be treated; - a first pipe 13 connected, on the one hand, to the said suction scoop 6, 6', and, on the other hand, to a vacuum source; - a second circuit 16 extending the first pipe 13 with a view to transporting the mud (sludge) from the said platform 1 to an evacuation zone; - adjustable mechanical linkage members 17 between the said platform 1 and the support 2 of the suction scoop 6, 6', this mechanical linkage being capable of allowing the said support to be towed by the platform.

Description

The present invention relates to a device for ensuring at regular intervals the necessary operations of cleaning a liquid medium on the bottom of which have deposited sediments constituting sludge.

The invention relates in particular to water bodies such as ponds or lagoons but also streams.

It is known that bodies of water, or streams, must at regular intervals, just being engorged and obstructing sources of pollution for the environment, be subjected to a cleaning, operation during which sludge sedimented over several years is evacuated.

The methods used are often empirical and consist for example of completely emptying the pond when the latter is controlled by a restraint which allows manual cleaning.

Installations and devices are also known which make it possible to perform a cleaning of the sedimented layers at the base of the liquid medium and which proceed either by means of sampling and direct recovery such as buckets mounted on wheels or on a chain, or by suction and taken back by evacuation ducts.

The devices of the latter type proceeding by suction are generally associated with a liquid projection at the suction head, projection which aims to resuspend the sedimented phases and which are then entrained in'the liquid medium sucked.

This technique is generally used for sediments of a mineral nature (silting).

This technique is not appropriate in the case where it is desired to eliminate the muddy bottom layers of the liquid medium, retaining extremely fine sedimented particles and generally derived from the decomposition of organic debris (including plant debris).

 fl is therefore desirable in the case of cleaning to remove the lower layers constituting sludge or sedimented vases in a body of water, to avoid resuspension of these lower layers; this resuspension would in fact have the opposite effect in that the higher liquid liquid would thus be polluted and the particles resuspended and returned to the upper layers could no longer be removed during the cleaning phase and would be sedimented again after a short time.

 = 1 is therefore desirable in the context of the cleaning of a water body of the pond or lagoon type or in the case of a natural or artificial watercourse (canal) to proceed in a gentle manner by taking the layer exactly bottom located at the bottom and corresponding to sediment (mud or mud) to be removed.

In particular, the invention applies, but not exclusively, to water bodies used for the purification of wastewater by lagooning.

It is safe to say that lagooning is a biological purification process that removes most of the soluble pollution contained in the water to be purified.

The wastewater treatment is carried out by routing the effluent subjected to treatment in several successive lagoons arranged in series; at the end of the last the water thus purified can join the natural environment.

The lagoons thus used are artificial ponds dug in the ground without adding surfacing, especially in concrete. And according to the depths of the lagoon, between 1 m and 4 m, there are lagoons of aerobic, anaerobic or aerobic type with oxygen supply by surface aerator.

The solids fall and settle on the bottom of the pond creating a layer of solid material decanted.

The accumulation of these solids makes cleaning necessary and the latter must be undertaken at relatively long intervals of between 5 and 10 years.

It is understood that in this case, and as explained above, it is desirable that the sample is limited to the sedimented sediment layers on the bottom without significant removal of water.

The invention aims to meet these needs and relates for this purpose according to a first object a movable cleaning device easily set up and movable between several basins successively submitted to a sludge removal treatment.

The assembly according to the inveniion realizes in fact an autonomous equipment which can be quickly put in place during the treatment of a basin or a set of basins then taken back and transported by road towards a new zone of activity .

To this end, the invention relates to a device for discharging sludge sedimented at the bottom of a liquid medium, in particular for cleaning a plane or stream, the device being of the type comprising suction means connected to means for transferring the sludge sucked and it is characterized in that it comprises a) at least one mouth of aspiratwon sludge b) a movable support of said mouth, this support being able to move parallel and following the pt Dfil the bottom of the liquid medium and the support is suitable for mair, enir said suction mouth at the appropriate level relative to the bottom to collect the muddy layer c) a platform mounted on flotation means and having means of movement on the surface of the liquid medium to be treated d) a first conduit connected on the one hand to said suction mouth and on the other hand to a source of depression, this first conduit being able to ensure the transport of the sludge sucked since the suction mouth towards said platform; e) a second duct extending the first duct for transporting the sludge from said platform to an evacuation zone outside the treated liquid medium; f) mechanical connecting members adjustable between said platform and the support of the suction mouth, this mechanical connection being able to allow the traction of said support and its displacement relative to the bottom of the liquid medium as a function of the displacements of the platform.

According to another characteristic, the suction mouth is constituted by at least one cylinder disposed horizontally and comprising a longitudinal slot able to be arranged in the immediate vicinity of the bottom of the treated liquid medium for the purpose of taking up the sludge, said cylinder being connected to said first evacuation pipe.

And preferably the device comprises two suction mouths each consisting of a horizontal cylinder, the two cylinders being arranged one above the other and each cylinder has a longitudinal slot, the upper cylinder being connected to the first conduit discharge with interposition of a valve to thereby put in activity the lower mouth alone, or the lower mouth and the upper mouth simultaneously.

More preferably the support of the suction mouth consists of two parallel pads adapted to slide on the bottom of the liquid medium, the two pads being connected by at least one cylinder forming said suction mouth.

And more particularly the support is in the form of a sled mounted on the two sliding pads and it comprises a fairing forming a recess, consisting of two side walls arranged parallel to the pads and interconnected by a horizontal ceiling wall located substantially at the upper level of the slot forming the highest suction mouth and said ceiling wall is extended in the direction of advancement of said support sled by a hinged flap visor and adjustable angle relative to the horizontal.

According to a feature of the invention at least the first conduit connecting said suction mouth to the platform and consisting of a flexible conduit.

According to another feature, the platform comprises means for lifting the support sled and these means consist of a set of pulleys driven by any suitable mechanical member and adapted to receive ropes connected to said support sled, these lifting means being thus suitable for vertically moving the support sled between an inactive and waiting position at the platform and an active position substantially in line with the first position, and said platform comprises for this purpose a floor provided with a removable central door in view the passage of the support sled between its idle waiting position and its active position resting on the bottom of the treated liquid medium.

It is also expected that the platform is based on two removable floats held by straps.

The platform is advantageously displaceable being associated with at least one guide wire fixed by its two ext-rémités two arresting points, and the platform comprises mechanical means such as a rotary drum cooperating with said cable to ensure the displacement of the platform along the cable.

The connecting members between the platform and the support sled are more particularly constituted of one and preferably two chains connecting the front part of the platform, in the direction of displacement of the latter, to the front part of the sled support and towed by said platform.

The platform may also include a pumping unit ensuring the suction of sludge at the suction mouths and also ensuring the discharge of the sludge from said platform to an outside receiving zone via the second conduit
According to a development of the invention is also provided that the device is associated with earth moving means formed of the tray of a trailer or a truck and said plate comprises means for moving the platform (including its sled support in the inactive position) between said plate, for transport on land, and the liquid medium for the introduction of the device in the liquid medium to be treated, these displacement means comprising in particular lifting and / or traction members and two removable ramps.

Other features and advantages of the invention will emerge from the description which follows and which is given by way of nonlimiting examples with reference to the appended drawings in which
FIG. 1 represents a general sectional view of the device in place on the treated liquid medium while FIG. 2 represents a detailed perspective view of the sled supporting the suction mouths.

According to all of the figures, the device comprises an upper platform 1 intended to float on the surface of the body of water, and a sampling or recovery head 2 resting on the bottom of the liquid medium.

This liquid medium consists for example of a lagoon or a pond 3 and on the surface 4 constituting the bottom is sedimented sludge 5 constituting the muddy or semi-liquid phase to be sampled.

The sampling is carried out by the suction mouths 6 and 6 'consisting of longitudinal slots arranged on two superimposed cylinders 7 and 7' respectively.

These two cylinders are arranged horizontally and parallel to the plane 4 constituting the bottom of the liquid medium on which rest the muddy phases to be resumed.

The two cylinders 7 and 7 'are arranged transversely to the direction of advance of the assembly illustrated by the arrows 8 and 8'.

The two cylinders 7 and 7 'are associated with a duct forming fairing to guide the suction of the ends.

This receptacle is formed of two side walls 9 and 9 'and the horizontal ceiling panel 10.

The front edge of this panel 10 supports a hinged flap 11, extending the panel 10 forward and forming a visor, adjustable angle relative to the horizontal.

The whole of this fairing guides the muddy phases thus sucked towards the rear panel formed by the two cylinders 7 and 7 'superimposed and whose slots or suction ports 6 and 6' are thus able to take up by suction the sludge presenting itself. facing said slots.

The set of two cylinders 7 and 7 'and its associated fairing rests on the two lateral pads 12 and 12' which slide on the surface a forming the bottom of the liquid medium.

The two superposed cylinders 7 and 7 'are connected to the suction ducts 13 by the recovery column 14 connected at its base to the lower cylinder 7 and communicating through the valve 15 with the upper cylinder 7'.

 it is thus possible according to the open or closed position of the valve 15 to operate the suction head mounted on the support sled either from a single lower suction mouth 6 or by also putting in the active position , in addition to the suction mouth 6, the upper mouth 6 '.

It is thus possible to marry at best the thickness of the muddy layers to be eliminated.

The recovery tube 13 or suction tube is formed of a hose which therefore allows a clearance between the sled support of the suction head 2 and the platform 1.

This tube or flexible conduit leads to the platform 1 and extends thereafter through the tube 16 leading to the discharge zone.

This evacuation can be a spreading area located nearby, or a means of transport including a tanker truck.

In the case where the recovery is carried out by tanker truck, the vacuum source is obtained at the level of the vacuum pump equipping the tanker truck; This gives a vacuum pump which makes it unnecessary in this case to set up and use a pump on the platform itself.

The adjustment of the angle of the flap forming an articulated visor, makes it possible to adapt the height of the suction section of the downcomer to the thickness of the muddy zone to be treated and which can be easily identified previously by a coring.

The support sled of the suction mouth (s) is connected to the upper platform 1 located above the level of the water line through the flexible conduit 13 conveying the sludge discharged; but a mechanical connection formed by a cable or preferably chains 17 ensures the kinetic solidarity of the movement of the sled 2 relative to the floating platform 1.

This platform consists of a floor 18 supported by two floats 19,19 'preferably removable and held by strap.

On the floor 18 is built a super structure formed of a flush 20 allowing in particular the cooperation of the platform 1 with the ancillary devices described below.

The platform 1 is associated with a guide cabal 21 secured at both ends in two anchor points, for example on two opposite banks of the lagoon or basin.

This guide wire passes through two opposite slots respectively 22,22 'the structure forming the frame 20 so as to ensure the positioning of the platform between the two lashing points.

The guide cable 21 cooperates with mechanical means for moving the entire platform along the cable.

These means may be constituted for example by a pulley or a drum 23 associated with mechanical means for rotating and thus allowing to ensure the displacement of the platform 1 along the cable in a linear movement preferably continuous and regular.

It is understood that in this movement by the play of the chains 17,17 'the platform drives the lower support sled defining the suction head 2; so that the suction assembly is driven to progress regularly by sucking progressively sedimented layers that is to say the sludge deposited on the bottom 4 of the basin.

The structure or frame 20 of the platform also comprises lifting means for ensuring the displacement of the sled and the suction assembly 2 from the active position resting on the bottom of the basin 4 as shown in solid lines on the FIG. 1, to a waiting or inactive position resting on the floor 18 of the platform and represented in dotted lines in FIG.

These lifting means consist, for example, of a set of pulleys respectively 2.24 'able to drive the ropes 25, 25' supporting the sled and thus able to ensure the movement of this sled vertically between its active position and its position. 'waiting.

To ensure the passage of the sled between these two positions the floor 18 has a central recess with a removable hatch.

Optionally it can be provided on the platform a suction pump which thus ensures the vacuum allowing the suction and suction sludge at the mouths 6 and 6 'and beyond the discharge, by the hose 16 sludge thus called to the disposal area (spreading or storage or recovery in a container such as a tank).

Advantageously and according to a development of the invention the device thus described may itself be associated with a means of transport and transport on land, particularly by road.

This means of transport may thus consist of the plate of a trailer or a truck, the tray being provided to receive the platform 1, on the floor 18 of which is then in the waiting position the sled constituting the head of suction 2.

In this case the plate provided for moving the assembly is equipped with means adapted to ensure the passage of the platform (integrating the suction sled in the waiting position) between said plate (for transport or storage) and the launch.

These displacement means may consist of lifting members (crane) or traction members associated in particular with ramps boring inclined plane.

It can be seen that the device according to the invention thus constitutes a homogeneous unit which makes it possible to bring a cleaning unit of a pond, in particular a lagoon pond or a watercourse, which can be returned immediately. operational and can be left in place by sweeping the bottom of the pond for cleaning and sludge removal.

It is expected that the suction and recovery of sludge from the bottom of the basin is done under particularly mild conditions and therefore avoiding a resuspension of fine particles that would disturb the quality of the water.

The evacuation can be exactly dosed according to the thickness of the sedimented layer to be removed so that the recovery is limited to the muddy phases with minimal parasite removal and recovery of water.

Claims (10)

 F. EV E1Dl CATIONS  1 - Device for the evacuation of sedimented sludge at the bottom of a liquid medium, in particular for cleaning a plane or watercourse, the device being of the type comprising suction means connected to sludge transfer means aspirated and is characterized in that it comprises a) at least one sludge suction mouth t) a movable support (2) of said mouth (6,6 '), this support being able to move in parallel and in according to the profile of the bottom (4) of the liquid medium and the support is adapted to maintain said suction mouth (6,6 ') at the appropriate level with respect to the bottom to collect the muddy layer (5) c) a platform (t ) mounted on flotation means (19, 19 ') and comprising displacement means (2i, 23) on the surface of the liquid medium to be treated d) a first duct (13) connected on the one hand to said mouth (6 , 6 ') suction and secondly to a source of depression, the first conduit being able to ensure the transport of sludge sucked from the suction port (6> 6'j to said platform (1) e) a second conduit (16) extending the first conduit (13) for the transport of sludge from said platform (1) to a external discharge zone to the treated liquid medium f) adjustable mechanical connecting members (17) between said platform (1) and the support (2) of the suction mouth (6, 6 '), this mechanical connection being suitable to allow the traction of said support and its displacement relative to the bottom of the liquid medium depending on the displacement of the platform. 2 - Device according to claim 1, characterized in that the suction mouth consists of at least one cylinder (7,7 ') disposed horizontally and having a longitudinal slot (6,6') adapted to be arranged at immediate proximity of the bottom of the treated liquid medium for the recovery of sludge, said cylinder being connected to said first discharge duct (13). 3 - Device according to claim 1, characterized in that it comprises two suction mouths each consisting of a horizontal cylinder (7,7 '>, the two cylinders being arranged one above the other and each cylinder has a longitudinal slot (6, 6 '), the upper cylinder (7') being connected to the first discharge duct (13) with the interposition of a valve (15) making it possible to activate the mouth lower (6i only, the lower mouth (6) and the upper mouth (6 ') simultaneously. 4 - Device according to. one of claims 1, 2 or 3, characterized in that the support (2> of the suction mouth consists of two parallel pads (12, 12 ') capable of sliding on the bottom (4) of the liquid medium the two pads being connected by at least one cylinder forming said suction mouth. 5 - Device according to claim 4, characterized in that the support (2) is in the form of a sled mounted on the two sliding pads (12, 12 ') and it comprises a fairing forming a baffle, consisting of two side walls ( 9,9 ') arranged parallel to the pads and interconnected by a horizontal ceiling wall (10) located substantially at the upper level of the slot (6') forming the highest suction mouth and said ceiling wall is extended in the direction of advancement of said sled support by a hinged flap (forming a visor and adjustable angle relative to the horizontal. 6 - Device according to one of claims i to 5, characterized in that the platform (1) comprises lifting means of the support sled (2) and these means consist of a set of pulleys- (24, Z4 ' ) driven by any suitable mechanical member and adapted to receive filirs (25,25 ') connected to said support sled (2), these lifting means being thus able to move the support sled vertically between an inactive position and waiting at the level of the platform and an active position substantially in line with the first position, and said platform comprises for this purpose a floor (18) provided with a removable central trap for the passage of the sled support between its idle waiting position and its active position resting on the bottom of the treated liquid medium. 7 - Device according to one of claims 1 to 6, characterized in that the platform is movable being associated with at least one guide cable (21) fixed by its two ends at two lashing points, and the platform comprises of mechanical means such as a rotary drum (23) cooperating with said cable to move the platform along the cable. 8 - Device according to one of claims 1 to 7, characterized in that the connecting members between the platform (1) and the sled carrier (2) are more particularly consist of one and preferably two chains (17.17 ') connecting the front part of the platform, in the direction of displacement of the latter, to the front part of the sled support and towed by said platform. 9 - Device according to one of claims 1 to 8, characterized in that the platform comprises a pumping unit ensuring the suction of sludge at the suction mouths and also ensuring the discharge of the sludge from said platform to a outdoor receiving area via the second conduit. 10 - Device according to one of claims 1 to 9, characterized in that it is associated with earth moving means formed of the tray of a trailer or a truck and said plate comprises means for moving the platform (with its carrier traneau inactive position) between said plate, for transport on land, and the liquid medium for the establishment of the device in the liquid medium to be treated, these moving means comprising in particular lifting members and / or traction as well as two removable ramps.