RU2606282C1 - Water intake unit of an irrigation system - Google Patents

Abstract

FIELD: land reclamation.

SUBSTANCE: invention relates to melioration systems and structures and can be used to perform irrigation water intake from mountain and submountain rivers which are characterized by high rate of water flow and presence of a large number of suspended and bottom sediments. Design of water intake unit of an irrigation system comprises flow coated water intake canal 1 with variable section connecting the beginning and end of the river bend 2 or running parallel to river bed 2. Water intake galleries 4 are built into the canal bottom, the upper part of the galleries is a filter panel. Water flows by gravity from water intake galleries 4 into accumulating tank 5 from which it is supplied on irrigated sections.

EFFECT: technical result is providing uninterrupted supply of water into an irrigation system and its protection against ingress of suspended and bottom sediments, as well as floating garbage under the conditions of hydrological regime of mountain and submountain rivers.

1 cl, 3 dwg

Description

FIELD OF THE INVENTION

The invention relates to the field of reclamation systems and structures and can be used for water intake for irrigation of land from mountain and foothill sections of rivers, which are characterized by high water flow rates and the presence of a large number of suspended and bottom sediments.

State of the art

Known water intake with a bottom grate (SU 437825 A1, 07/03/1975), including a water intake gallery and sand gravel, characterized in that in order to ensure a non-portable fence with limited washing costs, a cylindrical chamber with a water intake gap is located in the water intake gallery. The disadvantage of this design of the intake unit is the low efficiency of water purification from suspended sediment. Sand gravel traps unsatisfactorily operate on water conduits with high flow rates, while the discharge of water to sediment washing reaches 10% or more. Lightening i.e. active processing in sand gravel traps, only part of the irrigation water is subject and sediment fractions with a diameter of 0.25 mm or more enter the clarified water, which is unacceptable for closed irrigation systems.

Known bottom trellised water intake with a wash chamber (Hydrotechnical structures: textbook for universities / IM Volkov [et al.]. - M .: Kolos, 1986. - 464 p.), Which consists of a low dam with a water intake gallery under crest or threshold of a dam blocked by a lattice. Water flowing through the intake of the dam enters the bottom gallery through a grate. From the gallery, water is drained into the chamber where sedimentation occurs. From this chamber, water enters the irrigation canal. This chamber is periodically washed, and precipitated sediments are washed off through shield openings into the downstream. The disadvantages of this design include periodic operation of the intake, i.e. technological breaks are required to clean the sediment chamber. A significant drawback is that for the successful operation of this type of water intake, the mandatory presence of operating personnel is required. Also, the operation of the water intake unit with a periodic interruption of water supply for sediment removal does not meet the requirements of continuous irrigation technology in progressive ways.

Known bottom trellised water intake with shield holes on the spillway front (Hydrotechnical structures: textbook for high schools / IM Volkov [et al.]. - M .: Kolos, 1986. - 464 p.), In the construction of which two methods are used sediment control: 1) the creation of a transverse circulation in the upper pool, in which the bulk of bottom sediments will be discharged into the lower pool through the discharge shield part of the dam, bypassing the trellised water intake gallery; 2) the capture of a significant part of bottom sediments to the intake gallery with the help of a nano-intercepting trench. The disadvantages of this design include poor water purification from suspended sediment.

Known under-channel filter intake of combined construction (RU 2518634 C2, 06/10/2014), which contains a drainage gallery, on top of which is arranged a filter intake, consisting of a metal grate and laid on top of it in two dense rows of filtering flexible mattresses. Flexible mattresses are made of light fascia wrapped in a geogrid. The main water stream flows freely on top of the gallery’s water intake, and part of the water, under the influence of pressure, passes through the flexible mattresses of the upper and lower rows to the drainage gallery, since the light fascines from the reeds from which the flexible mattresses are made have good drainage properties. At the same time, water is also purified from suspended particles, flexible mattresses of the water intake work both as drains and filters. Due to the high slope of the upper row of water intake mattresses, most of the sediment that enters there with a stream of water does not linger, is carried away and washed off by water, only a small part of the sediment penetrates into the furrows of flexible mattresses (mainly suspended sediment). After a certain time of the flood period of the river, a turbid stream of water can lead to clogging (clogging) with suspended sediments of light fascines of the upper row of mattresses. As a result, the efficiency of the water intake (throughput) can be reduced by half or more. Therefore, the main drawback of this design is the need to replace the upper row of mattresses when they are clogged (clogged) with sediments, as a result of which this design acquires all the disadvantages inherent in the bottom trellised water intake with a washing chamber, which are given earlier.

The closest technical solution is a layered-lattice water intake (Hydrotechnical structures: textbook for universities / I.M. Volkov [et al.]. - M .: Kolos, 1986. - 464 p.), Which is developed on the basis of the law about the obstruction flow and bypassing it with bottom sediment. Hollow bulls, which are located above the intake gallery located in the body of a spillway dam, serve as a streamlined barrier in the layered-lattice water intake. Due to the occurrence of a circulation current in front of and along the bulls, a bottom strip appears, free from bottom sediments, in which the intake gratings of the galleries are arranged. The disadvantage of this design is the lack of protection against suspended sediment, for the cleaning of which it is necessary to arrange additional facilities.

A common drawback of all of these designs of water intake nodes is that they are arranged in the riverbed, which negatively affects the convenience of their maintenance or repair and affects the ichthyofauna of the river.

Disclosure of invention

The objective of the invention is to create a design of a water intake unit, which provides continuous water intake from mountain and piedmont sections of rivers for irrigation needs and its purification from suspended and entrained bottom sediments without the use of sedimentation tanks and sand gravel traps.

The technical result of the invention is to ensure uninterrupted water supply to the irrigation system and its protection against the receipt of suspended and bottom sediments, as well as floating debris in the conditions of the hydrological regime of mountain and foothill sections of rivers.

The specified technical result is achieved by arranging the intake unit of the irrigation system, the design of which is characterized by the presence of a lined intake channel connecting the beginning and end of the river bend or arranged parallel to the river channel. Protection from bottom sediments is ensured by the fact that the entrance to the canal is located on a concave section of the river, and the mark of the bottom of the channel is higher than the mark of the bottom of the river bed. The channel is flowing, and the discharge part of the channel must provide water transit with speeds exceeding the non-silting rate for these conditions (sediment parameters). Intake galleries are built into the bottom of the canal, the upper part of which is a filtration panel. The diameter of the holes (through pores) of the filtration panel should be less than the diameter of the cleaned fraction of suspended sediment. Under the influence of gravitational force, water passes through the filter panel and enters the water intake gallery, and suspended sediment is trapped on the filter panel. With the accumulation of sediment on the filter panel, water withdrawal by the gallery decreases and, consequently, the water flow rate along the intake channel and its flow rate increases. This leads to the washing away of sediment from the surface of the filtration panel, the flow of water to the intake gallery is restored, and the sediment is transported to the spillway of the canal and further to the river bed. Since the water flow along the length of the channel decreases due to water withdrawal by the galleries, the channel of the channel has a variable cross-section, the area of which decreases from the first in the direction of the gallery flow to the last. This is necessary to maintain the required flow rates.

From the water intake galleries, water is supplied to the storage basin, from which it is delivered to irrigated areas using pressure pipelines or in another way.

Description of drawings

The water intake assembly of the irrigation system is illustrated in FIG. 1 ÷ 3. In FIG. 1 shows a diagram of the intake unit of the irrigation system (plan). In FIG. Figure 2 shows a cross section of the intake unit of the irrigation system along the intake channel (section AA). In FIG. 3 - section of the intake unit of the irrigation system through the intake gallery (section BB).

The implementation of the invention

The water intake node of the irrigation system includes the following elements: water intake channel 1, riverbed 2, filter panel 3, water intake galleries 4, water storage basin 5, pressure pipelines 6.

Intake channel 1 draws water from the riverbed 2. Under the influence of gravitational forces, water passes through the filtration panel 3 to the intake galleries 4, through which it enters the water storage basin 5. From this basin 5, using pressure pipelines 6 or otherwise, water is delivered to irrigated areas .

Protection against bottom sediment load is ensured by the fact that: 1) the entrance to the canal is located on a concave section of the river, where the circulation currents arising on the bend of the stream carry bottom sediments to the opposite convex bank; 2) the bottom mark at the entrance to the canal is higher than the mark of the bottom of the river bed, which ensures the intake of water into the canal from surface horizons and excludes the ingress of a significant part of bottom sediments from the river into the canal. In addition, bottom and suspended sediment entering the intake channel 1 are separated from the intake water by filter panels 3 of the intake galleries. With the accumulation of sediment on the filter panel, water withdrawal by the gallery 4 decreases and, consequently, the water flow through the intake channel 1 and its flow rate increase. This leads to the erosion of sediment from the surface of the filtration panel 3 and the water flow to the intake gallery 4 is restored, and the sediment is transported further along the intake channel 1 to the riverbed 2.

Claims (1)

The water intake unit of the irrigation system, including the water intake channel, water intake galleries and a storage basin, the design of which is characterized by the presence of a flowing lined water intake channel of variable cross section, into the bottom of which water intake galleries are integrated, the upper part of which is a filter panel, the diameter of the holes, namely the through pores, which must be smaller than the diameter of the cleaned fraction of suspended sediment.

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