ES1245246U - SEDIMENT CONTAINMENT SCREEN (Machine-translation by Google Translate, not legally binding) - Google Patents

Abstract

Sediment containment screen, which being of the type intended to be installed facing the set of drainage mouths (3) at the bottom of the dam (4), in order to avoid the introduction of sediment in said conduits, and which it has lifting means (7) by means of a crane (6), it is characterized in that it is constituted from a body (1) with an inverted semi-conical-conical configuration, open superiorly, later and closed by its lower base (2), body (1) that is movable on the surface of the dam regardless of its configuration by means of a system of wheels (5) in the upper area of contact between the screen and the dam. (Machine-translation by Google Translate, not legally binding)

Description

D E S C R I P C I Ó N

Sediment containment screen.

TECHNICAL SECTOR

The present invention relates to a device intended to isolate the mouths of the bottom drains of a dam from the surrounding sediment, in order to prevent it from entering the ducts with consequent technical and environmental damage.

The invention also includes a system of suction and pumping of sludge with vacuum cleaners distributed along the outer perimeter of the screen, and connected with the crowning of the dam, which allows periodic cleaning of the area in order to prevent the level of sediment exceeds the screen protection height.

BACKGROUND OF THE INVENTION

Sedimentation is one of the main problems facing all the reservoirs in the world. The consequences of excessive sediment accumulation caused by the construction of a dam are diverse and have a strong economic and safety and environmental impact. The solution is generally complex and expensive and involves periodic dredging in the areas to be released. This problem is aggravated by depth, since, from 50 meters on, very specific equipment and specialized divers are needed to increase the costs of eventual dredging. A suitable solution in these cases is to protect the intakes from the bottom drains (critical area of the dam) by installing screens that prevent the passage of solids in the medium term.

Trying to obviate this problem, the invention patent 2 156 549 is known, in which a damper device for vertically or slightly inclined faces is described, which in addition to the limitation of application to vertical or slightly inclined faces to which it mentions Its own title presents a problem in which the following aspects should be highlighted:

• The structure or screen has a semi-cylindrical configuration, which makes it not adapt to the current curves that appear due to the normal operation of the drains.

• Unwanted vibrations may appear that put at risk the structural integrity of the screen and its union with the dam.

• The turbulence generated favors the appearance of cavitation that implies an accelerated degradation of the steel.

• The structure is lowered into modules that slide on metal counter guides, installed specifically for its installation, which requires additional underwater work.

• As mentioned above, the very nature of the counterguides, made up of Z-shaped metal profiles, limits the application of this solution to dams with vertical or slightly inclined faces, their application being unfeasible in arch or vault dams.

At the same time, said patent provides means for the perimeter cleaning of the screen, materialized in a series of compressed air injectors around the structure, so that the subsequent removal of the mud is carried out with a conventional impeller pump.

In this sense, the presence of electrical components exposed in a long time to such extreme conditions does not offer guarantees of durability in the medium term, which makes it necessary to replace the pump and its connections with regularly, with consequent underwater material and labor costs.

EXPLANATION OF THE INVENTION

The sediment containment screen that is recommended solves in a fully satisfactory way the problems previously exposed, in each and every one of the aspects discussed, based on a simple but effective solution.

For this, and more specifically, the screen of the invention is constituted from an inverted semi-truncated-conical body, closed by its lower base, which allows the mouths of the bottom drains of a dam to be isolated from the surrounding sediment, in order to prevent it from entering the ducts with consequent technical and environmental damage.

The inverted semi-frusto-conical configuration largely adapts to the current flow by the normal operation of the drains.

Furthermore, it is more effective in preventing bottom currents reaching its lower base and creating turbulence from causing an undesired rise of the sediment into the structure.

The screen is dimensioned for operation at great depth and high flow, without vibrations and with greater durability.

The proposed device has a high-pressure air injection system to promote sludge disaggregation.

Additionally, a series of diffuser crowns are included distributed around the structure's contour and connected to a crowning compressor, which by means of the injection of air at a controlled pressure allows the suction of the sediment and its pumping using Air-Lift technology, up to a point previously chosen by the developer.

The absence of moving and electrical parts favor the durability of the system even in the long term without the need for maintenance.

According to another of the characteristics of the invention, the screen includes a wheel system in the upper area of the contact between the screen and the dam. Said system is made up of a multiplicity of wheels such that the tension transmitted to the concrete of the dam by the own weight of the screen is always kept in an acceptable range.

This configuration allows the solution to adapt to all types of dams, regardless of their geometry and height and significantly reducing implementation costs.

The support of the wheels on the body of the dam during the descent of the structure makes the total load that the crane has to move less and consequently reduces the costs of this phase.

In this way, a much more effective sediment containment device is achieved, easy to implant and maintain, with lower associated costs.

BRIEF DESCRIPTION OF THE DRAWINGS

To complement the description that will be made below and in order to help a better understanding of the characteristics of the invention, according to a preferred example of practical embodiment thereof, a set of drawings is included as an integral part of said description. where, by way of illustration and not limitation, the following has been represented:

Figure 1.- Shows a perspective detail of a containment screen for sediments made according to the object of the present invention.

Figure 2.- Shows a profile view with an enlarged detail of the screen applied to an arch dam.

Figure 3.- Shows a profile view with an enlarged detail of the screen applied to a slightly inclined vertical facing dam.

PREFERRED EMBODIMENT OF THE INVENTION

In view of the reviewed figures, and especially of figure 1, it can be seen how the sediment containment screen is constituted from a body (1) of inverted semi-frusto-conical configuration, open superiorly, later and closed for its lower base (2), of dimensions in accordance with the set of drainage mouths (3) at the bottom of the dam (4), in order to avoid the introduction of sediment in said conduits.

This configuration is adapted to a great extent to the flow of current by the normal operation of the drains, being more effective in preventing the rise of sediments by water currents by virtue of said surface inclined outwards.

As can be seen in Figures 2 and 3, the screen includes a system of wheels (5) in the upper area of contact between the screen and the dam, made up of a multiplicity of wheels such that the tension transmitted to the concrete of the prey by the own weight of the screen is always kept in an acceptable range.

More specifically, the screen can be raised by means of hoisting (7), associated with a crane (6) by sliding by means of its wheels (5) on the surface of the dam, for its initial maintenance or implantation, which that allows the screen to be used interchangeably in all types of dams, regardless of their geometry and height and significantly reducing implementation costs. The support of the wheels (5) on the dam body (4) during the descent of the structure makes the total load that the crane (6) has to mobilize less and consequently reduces the costs of this phase.

The screen has a high pressure air injection system distributed on its external surface to favor the disaggregation of the sludge.

As previously stated, in addition, the device has a series of diffuser crowns distributed around the structure's contour and connected to a crowning compressor, which by means of the injection of air at a controlled pressure allows the sediment suction and pumping by Air-Lift type pumps to a point previously chosen by the developer.

Claims (3)

1a.- Sediment containment screen, which being of the type intended to be implanted facing the set of drainage mouths (3) at the bottom of the dam (4), in order to avoid the introduction of sediment in said conduits, and which has lifting means (7) by means of a crane (6), it is characterized in that it is constituted from a body (1) with an inverted semi-conical configuration, open superiorly, later and closed by its lower base (2 ), body (1) that is movable on the surface of the dam regardless of its configuration by means of a system of wheels (5) in the upper area of contact between the screen and the dam. 2a.- Sediment containment screen, according to claim 1, characterized in that it includes a high pressure air injection system distributed on its external surface to favor the disaggregation of the sludge. 3 a.- Sediment containment screen, according to claim 1, characterized in that it includes a series of diffusion crowns distributed around the structure's contour and connected to a compressor arranged in crowning, determining a mechanism for suction and pumping of the sediment by pumps Air-Lift type.