WO2022079648A1

WO2022079648A1 - Device for cleaning bodies of water of silt deposits and extracting sapropel at natural moisture content

Info

Publication number: WO2022079648A1
Application number: PCT/IB2021/059436
Authority: WO
Inventors: Владимир ДЕМЕНТЬЕВ
Original assignee: Владимир ДЕМЕНТЬЕВ
Priority date: 2020-10-15
Filing date: 2021-10-14
Publication date: 2022-04-21
Also published as: RU2745146C1

Abstract

The invention relates to the field of hydromechanically cleaning bodies of water of silt deposits, with the extraction of sapropel at natural moisture content. The technical result is a more reliable device, a reduction in labour costs and an increase in the quality of the sapropel obtained. The claimed device for cleaning bodies of water of silt deposits and extracting sapropel comprises: a chamber equipped with a dredging pump having a suction pipe; an intake element; and a discharge element. Furthermore, the dredging pump mounted in the chamber is a progressive cavity pump with an adjustable rotor speed, which is fastened to the bottom of the chamber. The intake element is configured in the form of a scraper scoop provided with a cover and, at its inlet, a mesh/blade, and is mounted for horizontal movement. The chamber is integrated with the scraper scoop, the cover of which is fastened to the bottom of the chamber. The front end wall of the chamber is mounted at an acute angle to the bottom of the chamber, wherein the bottom of the chamber, the cover and the bottom of the scraper scoop are parallel with one another. The bottom of the chamber and the cover of the scoop each have one coaxial opening for the passage of sapropel. The suction pipe of the dredging pump is arranged coaxially with said openings for the passage of sapropel and is fastened to the bottom of the chamber. The pump is provided with an outlet pipe disposed at the rear end wall of the chamber and connected to the discharge element, which is configured in the form of a pressure pipe connected to a floating vessel.

Description

DEVICE FOR CLEANING WATER BODIES FROM SLUD DEPOSITS AND EXTRACTION OF NATURAL HUMIDITY SAPROPEL

The invention relates to the field of hydro-mechanized cleaning of reservoirs from silt deposits, including the extraction of natural moisture sapropel (NWS) and its use, for example, as a fertilizer, filler in the production of building materials, in medicine.

There are a large number of types of soil intake devices (GZU) designed for the extraction of sapropels.

1. confuser-scraper type: GTD-1.8 or GD-3.5;

2. rotary bucket type: RKGU;

3. screw-scraper type: UDS-15, ANB-752;

4. milling screw type: FSHDU. Before the suction of the pulp, the soil is loosened and mixed with water, as a result of which a suspension cloud appears in the water in the bottomhole zone, and the pulp enters the pump with a density significantly lower than the density of the developed silty rock by mixing it with water in a ratio of 1:4.. 1:25 because they were all designed for suction and work with centrifugal or axial flow pumps. And this main technological drawback of the equipment used leads to a number of other negative consequences arising from the use of these devices:

- suction of large volumes of water with their transportation to the shore, which leads to a drop in the water level in the reservoir with washing and collapse of the coastal edge of the reservoir;

- turbidity of water by suspended silt in the bottomhole zone with the spread of a cloud of suspension over large areas, and especially in flowing reservoirs;

- drainage and return of clarified water in large volumes with the alienation of large coastal areas for the creation of settling checks.

- long settling time, freezing, dehydration and drying of sapropel in settling tanks, which takes up to 12 months. At the same time, the main environmental requirement in the development of lake deposits of sapropel is the safety and inadmissibility of disturbing the continuous upper zone of the sapropel deposit, as well as the spread of suspended matter in the water, which leads to the mass death of hydrobionts (plankton and benthos)

There are other devices that use submersible pumps of the INGI type (submersible low-pressure soil pump), as well as submersible wells, which have all the above disadvantages.

A device according to patent No. 2348762 is known, where a scraper bucket equipped with a soil pump installed behind the back wall of the bucket is considered as a GZU, and a vibrator and a mixer are placed inside the bucket.

The device according to patent No. 2418914 was taken as a prototype, where a submersible or semi-submersible chamber with a hydraulically driven pump installed in it was used as a ROM.

The disadvantage of this device is the fact that the operation of such a device is possible only when the sapropel is in a very fluid state, and this exists only in the uppermost layer within 1 m, deeper the sapropel always has a pronounced plasticity and does not flow without the application of force. . In addition, the vertical arrangement of pipelines or the chamber itself contributes to a fairly rapid flow of water from above along the walls of the chamber and vertical sleeves to the entrance to the GZU, which leads to the erosion of sapropel with water along the walls and makes it impossible to carry out a stable excavation of sapropel of natural moisture (hereinafter referred to as NWM) for a long time with one site, and the movement of such a GZU in sapropel is difficult.

To prevent water from flowing along the walls of the gas pump and the pipeline from above, the gas pump in the form of a pipe during operation should have the largest possible deviation from the vertical, for example 45 degrees, but the slope increases the length of the gas pump and the load from its horizontal movement in sapropel, which leads to very large bending moments in the support nodes of the main memory unit and can lead to emergency situations.

The objective of the claimed invention is to eliminate these disadvantages.

EFFECT: increased reliability of the device by eliminating pump breakdowns when sapropel is drawn in in a natural viscoplastic consistency, reduced labor costs by eliminating additional operations for cleaning the extracted sapropel and improving the quality of the resulting sapropel.

This is achieved by the proposed device for cleaning reservoirs from silt deposits and extracting sapropel, including a chamber equipped with a soil pump with a suction pipe, an intake element, a discharge element in which, according to the invention: - an eccentric screw pump is installed in the chamber as a soil pump with adjustable rotor speed;

- the intake element is made in the form of a scraper bucket, equipped with a lid and a mesh-knife at the inlet, installed with the possibility of horizontal movement;

- the chamber is made combined with a scraper bucket, the lid of which is attached to the bottom of the chamber;

- the front end wall of the chamber is installed at an acute angle to the bottom of the chamber, while the bottom of the chamber, the cover and the bottom of the scraper bucket are parallel to each other;

- the bottom of the chamber and the bucket cover have one coaxial hole each;

- the soil pump is fixed on the bottom of the chamber with the help of fixing elements, while the flange of its suction pipe is fixed on the bottom of the chamber coaxially with the through holes in the bottom of the chamber and the bucket cover;

- the pump is equipped with an outlet pipe with a flange located at the rear end wall of the chamber and connected to the outlet element, made in the form of a flexible pressure pipeline. Such a GZU will ensure the retraction of sapropel in a natural viscous-plastic consistency, and not from the surface, but from the inside of the deposit from under the covering layer of sapropel with its transfer to a more mobile consistency without dilution with water.

The maximum suction capacity of the MSD will be provided by an eccentric screw pump with an adjustable rotor speed, built into the chamber to reduce the input resistance, and capable of creating a high vacuum at the input, regardless of performance.

The proposed pump will provide SWS supply to the surface and further transportation to the shore through the pressure pipeline. Combining the bucket with the camera has a number of the following advantages.

The bucket, due to horizontal movement, makes it possible to cut off (separate, cut off) the calculated volume of SWS from the pillar (without the formation of a suspension cloud) and prepare it for retraction by the pump (due to the destruction of the structural bonds of sapropel by cutting into small segments of the separable volume of SWS when it passes through the mesh-knife ), thereby reducing the shear resistance of small segments of the SEB by providing greater mobility between the cut segments of sapropel in front of the pump inlet.

The pump must retract the SEV due to the discharge (vacuum) created by the pump at the inlet pipe. The vacuum created by self-priming pumps does not usually exceed 0.06-0.08 MPa (megapascals, or 6-8 meters), which allows them to work with a viscosity of the pumped material up to 200 MPa-s (mi-pascals-second). Therefore, to reduce friction losses at the inlet, the pumps are lowered inlet and brought closer to the gas chamber, thereby reducing the length of the inlet pipe. Taking into account the fact that the viscosity of CEB is much higher than the specified viscosity limit (200 mPa-s) and can reach 1400 mPa-s, a solution is needed to increase the suction capacity of the HZU for working with viscous CEB.

The retracting capacity of this GZU is increased due to: - the use of an eccentric screw pump (EVP) operating with very viscous media (up to 1,000,000 mPa-s), which ensures the supply of WW to the surface and even its transportation to the shore through a pressure pipeline, since another indisputable advantage of the EVP is its ability to provide stable pressure on output up to 4.8 MPa, which cannot be allowed by any soil pump;

- by placing EWH in a submersible chamber, since the use of a submersible chamber makes it possible to use the external hydrostatic pressure of the liquid medium, and the pump placed in such a chamber experiences a hydrostatic backwater at the inlet equal to the depth of the chamber immersion. At a depth of, for example, -6 meters, SEV under a pressure of 0.06 MPa will put pressure on the walls of the submersible chamber, thus providing additional backwater and thereby increasing the retracting capacity of the GZU.

The combination of the bucket and the submersible chamber with the EWH located in it allows, on the one hand, to minimize the resistance of the SEV at the inlet, and on the other hand, to increase (strengthen) the retracting capacity of the EWH by creating an external hydraulic support for it, which will ensure the guaranteed retraction of viscous SEV.

The proposed device is shown in the drawings, in which, according to the invention:

Fig. 1a, 16, 1c schematically depict the design of the submersible chamber and ladle (options).

Fig. 2a, 26, 2e schematically depict the respective types of bucket construction.

Fig. 3a, 36, 3d schematically depict the respective views of the construction of the chamber and ladle shown in FIG. 1a and 16, 1c.

Fig. 4 schematically depicts a dredger equipped with an attachment in the form of a submersible chamber equipped with an eccentric screw pump and combined with a scraper bucket, which excavates sapropel from under the covering layer.

The device (Fig. 1a, 16) contains a horizontal chamber 1 with an intake element made in the form of a scraper bucket 2.

The chamber 1 has a cross-sectional shape in the form of an arch 3 supported by two vertical 4 (Fig. 1a) or inclined 5 (Fig. 16) side walls resting on the flat bottom 6 of the chamber 1. The bottom 6 on each longitudinal side has an external protrusion (shelves ) 7 with holes for attaching chamber 1 to bucket 2, and equipped with hole 8 for entry of sapropel from the bucket into the chamber (Fig. 1c).

Bucket 2 (Fig. 2a) of the scraper type, the bottom 9 of which is equipped with a cutting edge 10 at the entrance, and the side walls 11,12 at the entrance to the bucket have two loops 13 (Fig. 26) for attaching a two-branch sling 14 to the tension cable 15 (Fig. 4). The lid 16 of the bucket has two rows of pins 17 protruding from above, located along the side walls 12, for attaching the bucket to the bottom 6 of the submersible chamber. In the lid 16 of the bucket there is an outlet 18 for the sapropel outlet, around which there are fastener holes 19 of the inlet pipe 20 of the pump 21. The bucket 2 has a cross-sectional shape in the form of a rectangle with rounded corners 22 (Fig. 1a) or a trapezoid with rounded corners 23 (Fig. . sixteen). In the rear tail part of the cover 16 there is a row of holes 24 of the transverse attachment of the bucket to the bottom 6 of the chamber (Fig. 2c).

The geometric shapes of the main storage device, including both bucket 2 and chamber 1, are of great importance for ensuring the efficient operation of the main storage device:

The frontal surface of the MGD has a sharp angle of attack relative to the longitudinal axis of the MGD, including the grid-knife 25 and the front wall 26 of the chamber, thereby providing reduced resistance to penetration into the SEV and its movement in the thickness of the SEV, and also has a stabilizing effect on the horizontal movement of the MGD, since the thrust vector of the tension cable 15 has a pulling effect on the bucket 2. The conicity of the chamber 1 along the longitudinal axis also helps to reduce the resistance to the movement of the bucket 2 in the vertical plane and eliminates the SEV hanging over the bucket during the vertical lifting of the main storage device, as if the main storage bucket had only a flat horizontal cover 16.

With increased dimensions of the GZU (with a large width of the bucket), the side walls 12 of the bucket (Fig. 2c) can also be installed with an inward slope to reduce the protruding longitudinal shelves 7 formed between the base of the walls 12 of the chamber and the lid 16 of the bucket. This will also prevent the sapropel from hanging and reduce the resistance when lifting the GZU from the deposit.

The front end wall 26 of the chamber is installed at an acute angle to the bottom 6 of the chamber, and the mesh-knife 25 blocking the entrance to the bucket can be installed at different angles: acute (Fig. 3a), straight (Fig. 36), blunt (Fig. Sv ) to the bottom 6 of the chamber, while the bottom 6 of the chamber, the bottom 9 and the cover 16 of the bucket are parallel to each other. Grid-knife 25 (removable or stationary) completely blocks the entrance to the bucket in order to prevent large objects from entering the pump, and the step of the knives is taken within the capacity of the pump 21. The plane of the grid-knife 25 and the front wall 26 of the chamber can be combined in one plane in the case of working with a viscous-flowing or viscous-plastic medium, or they can have opposite overlapping at an acute angle in the case of working with a stiff-plastic medium or compacted high-ash sapropels or mineral silts. If the mesh-knife 25 is made non-removable, then an inspection hatch is made in one of the side walls 11 or 12 of the bucket, through which the bucket will be cleaned from inclusions that have fallen into it. In the case of a removable variant, the mesh-knife 25 is removed to clean the bucket.

The front wall 26 (Fig. Za-c) of the chamber is installed at an acute angle to the bottom 6 to reduce resistance and press the GZU to the bottom when the GZU moves forward, and the rear end wall of the chamber is made in the form of a removable cover 27, installed vertically to the bottom 6 and fixed bolted all around chamber using the end flange 28 of the chamber 1 through a sealed gasket (not shown), while the back cover 27 is equipped with a branch pipe 29, to which a flexible connecting sleeve 30 is hermetically attached.

The sleeve 30 (Fig. 4) is connected to the watercraft (dredger) 31 along an outwardly curved curve, exceeding the chamber immersion depth by at least 1.7 times in length in order to stabilize the GZU in height during its horizontal movement in the thickness of the sapropel. Sleeve diameter 30 is sufficient to accommodate:

- pressure hose 32 for supplying SEV, connecting the flange of the outlet pipe 33 of the pump 21 with the sapropel receiving hopper 34,

- hydraulic hoses 35 connecting the hydraulic drive 36 of the pump 21 with the hydraulic station 37,

- electrical cables 38 connecting the water level sensor in the chamber with the control panel 40 and, in the case of the electric version, the electric drive 36 of the pump 21 with the control panel 40

- and a safety cable 41 connecting the chamber 1 with the craft 31.

In chamber 1, an eccentric screw pump (EVP) 21 is installed with an adjustable SEV supply rate, the flange of the outlet pipe 33 of which is located at the rear end wall 27 of the chamber 1 and is connected to the flange of the pressure hose 32, and the flange of the inlet (receiving) pipe 20 of the pump 21 is attached to the bottom 6 of the chamber with bolts 19. Due to the fact that the EWH pump is eccentric (the rotor axis is displaced relative to the stator axis), vibrations occur when the rotor rotates. When the pump is installed on a rigid base, these vibrations are damped by rigid fastening of the pump foundation to the concrete base. In the case of fastening the pump 21 to the bottom 6 of the chamber 1, the vibrations from the pump are transmitted to the entire body of the gas pump, including the bucket. The GZU chamber is in a suspended state with a large degree of freedom of movement in three planes, therefore, vibrations from the pump 21 transmitted to the chamber and bucket, are transferred to the surrounding viscous medium, quenched in it, destroying structural bonds and reducing the shear resistance of the CEB.

Thus, using EWH 21 as a feed pump in the MCD, there is no need for additional use of vibrators, the functions of which in this design of the MCD are performed by the EWH itself.

The bottom of the chamber 6 and the cover 16 of the bucket 2 each have one coaxial hole, 8 and 18, respectively, for the passage of sapropel from the bucket to the pump. The flange of the inlet pipe 20 of the pump 21 is located on the same axis with the holes 8 and 18, and is bolted to the bottom 6 of the chamber 1 through the holes 19 located around the inlet 8 of the chamber 1. The diameter of the inlet 8 of the chamber 1 coincides with the diameter of the inlet pipe 20 of the pump 21 , and the diameter of the hole 18 in the lid 16 of the bucket 2 exceeds the diameter of the inlet 8 of the chamber 1 by an amount sufficient to allow the caps of the mounting bolts to pass through the hole 18 in the lid 16 of the bucket 2 when connecting the chamber 1 to the bucket 2. Around the inlet 18 above the lid 16 of the bucket 2 has a recess for placing a rubber sealing ring in it.

The GZU is equipped with a system of three cables: tension 15, to move the GZU forward; suspended 42, for raising or lowering the GZU to a given depth; safety 41, to prevent the loss of the GZU or the breakage of the connecting sleeve in the event of, for example, a break in the suspension or tension cables. The safety cable 41 perceives tensile stresses from the flexible connecting sleeve 30, which occur in it during the horizontal movement of the HMS forward in the viscous sapropel layer.

Ground intake device (GZU) operates as follows (Fig. 4).

With the help of a tension winch 44, slack is given to the tension cable 15 so that the joint of the cable 15 and the tension beam 14 sags below the bottom 9 of the bucket 2.

Then, using a winch 43, the submersible device in the form of a chamber 1 connected to a bucket 2 and a flexible sleeve 30, on a suspension cable 42 begin lower from the deck of the dredger 31 under water to a predetermined depth. The winch 44 at the same time continues to unwind the cable 15, making sure that the lifting cable 42 remains always in a vertical position in tension under its own weight. Dredger 31 stands still.

When the GZU is immersed under water by 1-1.5 meters, the motor 36 of the pump 21 is turned on at the lowest speed so that the pump stator is filled with water.

At the same time, the GZU continues to sink into the thickness of the sapropel due to its own weight as the length of the suspension cable 42 increases. The tension cable 15 remains weakened all the time due to the unwinding of the tension winch 44.

When the bottom 9 reaches a predetermined depth, the winch 44 switches to winding the cable 15 to tension it. After that, the speed of rotation of the rotor of the pump 21 is gradually increased so that the retraction of the SEV begins at a given depth, and at the same time, the consistency of the supplied sapropel at the outlet of the pressure pipeline 32, which is made of a composite material with reinforcement, is controlled. As soon as SEV appears at the outlet of the pressure pipeline 32, the number of revolutions of the stator is increased using the hydraulic station 37 and the sapropel receiving bin 34 is filled. pumping SEV from the receiving hopper 34 of the dredger 31 to the onshore storage hopper through a floating high-pressure pipeline.

The pump 21 and the dredger transfer pump (not shown) are set to operate in synchronism with the same capacity.

In this case, the operator constantly monitors the consistency of the sapropel entering the hopper 34.

As soon as the consistency of the sapropel entering the hopper 34 changes, from a pasty thick mass it becomes more mobile and fluid, it is necessary to reduce the rotational speed of the rotor of the pump 21 and the transfer pressure pump (not shown), respectively, and start horizontal advancing the GZU forward. To this end, the dredger 31, due to the front (or 2 front) papillon winches (not shown), begins to slowly move forward along the water surface of the reservoir, pulling the submerged GZU, which remains at a given depth, by means of a tension cable 15, while gradually increasing the speed pump rotor 21 and a transfer pressure pump (both of these pumps must work synchronously).

After the ropes of the front papillon winches are wound, the dredger 31 stops, both pumps stop, the GZU with the help of a lifting winch 43 rises on the lifting cable 42 of the cable from the water, and the dredger 31 with the help of the rear papillon winches returns back to the starting point of the entry. After that, the process described above repeats again.

With a small size of the reservoir, a short distance of transportation, a small excavation depth and a low lifting height, it is possible to carry out the transportation of SEV along the pressure hose 32 not to the hopper 34 on the dredger 31, but immediately to the onshore storage bin, by connecting the sleeve 32 to the floating pressure pipeline through a knife gate valve of the appropriate diameter, in order to prevent the backflow of sapropel from the pressure pipeline if necessary.

1 - camera

2 - bucket, intake element in the form of a scraper bucket

3 - chamber arch

4 - vertical side walls of the chamber

5 - inclined side walls of the chamber

6 - chamber bottom

7 - longitudinal shelves of the bottom with holes for fastening the chamber to the bucket

8 - inlet of the chamber for the passage of sapropel from the bucket into the chamber

9 - bucket bottom

10 - cutting edge of the bucket bottom

11 - side walls of the bucket (vertical version) 12 - side walls of the bucket (inclined version)

13 - two loops for attaching a pulling two branch sling

14 - two branch pull sling

15 - tension cable

16 - bucket cover

17 - two rows of bucket studs protruding from above

18 - ladle outlet for sapropel exit from the ladle into the chamber

19 - fasteners (bolted) of the pump inlet pipe

20 - inlet pipe of the pump with a flange

21 - EVN pump

22 - rounded corners (rectangular bucket option)

23 - rounded corners (trapezoidal bucket option)

24 - a row of holes for transverse fasteners

25 - mesh-knife

26 - front (front end) wall of the chamber

77 - rear end wall of the chamber in the form of a removable cover

28 - end flange of the chamber

29 - branch pipe of a removable cover for fastening a flexible connecting sleeve

30 - flexible connecting sleeve

31 - watercraft (dredger)

32 - pressure hose for supplying SEV

33 - pump outlet flange

34 - sapropel receiving bunker

35 - hydraulic hoses

36 - hydraulic pump drive (hydraulic motor) or electric motor

31 - hydraulic station

38 - electrical cables of the water sensor and power supply of the pump motor

(option)

39 - water level sensor in the chamber - control panel - safety rope - suspension rope - lifting winch - tension winch

Claims

Claim

1. A device for cleaning reservoirs from silt deposits and extracting sapropel, including a chamber equipped with a soil pump with a suction pipe, an intake element, a discharge element, characterized in that

- in the chamber, an eccentric screw pump with an adjustable rotor speed is installed as a soil pump, fixed on the bottom of the chamber;

- the bottom of the chamber and the cover of the ladle have one coaxial hole for the passage of sapropel;

- the suction pipe of the soil pump is placed coaxially with the holes for the passage of sapropel and is fixed on the bottom of the chamber;

- the pump is equipped with an outlet pipe located at the rear end wall of the chamber and connected to a discharge element made in the form of a pressure pipeline connected to the floating vehicle.

2. The device according to claim 1, characterized in that the chamber is submersible.

3. The device according to paragraphs. 1, 2, characterized in that the chamber has a cross-sectional shape in the form of an arch, supported by two vertical or inclined side walls resting on a flat bottom, while the edges of the bottom on each side have external protrusions with holes for fastening the chamber to the bucket lid .

4. The device according to claim 1, characterized in that the pressure pipeline is made of a composite material with reinforcement exceeding the length of the chamber immersion depth by at least 1.7 times.