SU1249111A1 - Method of constructing counter-seepage screen - Google Patents

Abstract

The invention relates to the construction of irrigation canals, in particular, to methods for creating screening screens thereon. The invention aims to reduce costs and the degree of pollution of the environment. This is achieved by the fact that in evaporation ponds drainage water is concentrated to a minimum salinity of 6-12 g / l with a content of sodium ions, respectively, 67-50%, the concentrated solution is injected into the channel of the channel several times during non-operating periods of the channel drinking the solution. Then seal the surface of the channel channel. As a result, a weakly permeable illuvial layer forms in the clay earthy channel of the irrigation canal, which acts as an anti-seepage screen. Due to the use of drainage water, the need for sodium salt is eliminated, which reduces costs and also the degree of pollution of the environment, in particular water bodies, into which drainage waters are discharged. with (L tc with

Description

one

The invention relates to the field of construction of irrigation canals and can be used to create impervious screens on them.

The purpose of the invention is to reduce the cost and degree of environmental pollution.

The method of creating a protofiltration screen, mainly in a clay-like ground layer of the irrigation canal, is carried out as follows.

On the territory adjacent to the irrigation canal, they create an accumulating capacity of the evaporator reservoir, which can be used to reduce the natural relief, for example, ravines, and beams. The prepared tank is filled with drainage, waters with a salinity of at least 3-4 g / l. During the summer period, which is the operational period of the irrigation canal, in the reservoir-evaporator, due to natural evaporation, the drainage waters are concentrated to a salinity of 6-12 g / l. In the non-operational autumn-winter period, the irrigation canal is released (given from fresh water, concentrated drainage water is fed into it from the reservoir-evaporator, leaving them in the canal until the next operational period, at the beginning of which The canal is washed with fresh water, washing out the remnants of the salt solution. These operations are repeated several times until an illuvial horizon is formed, after which the soil surface in the channel of the channel is additionally compacted to form a counter filter

 screen.

one

The proposed method is applicable in loamy and clay soils containing at least 45-60% clay particles. In order to implement the method, saline drainage waters are hydrophobic, in which sodium ions prevail over calcium and magnesium ions, which often occur under actual conditions

When interacting with a solution containing sodium ions, the crust of soil – soil fraction changes from a coagulated state to a peptized state, as a result of which a weakly permeable illuvial horizon is formed. Studies have found that when the sodium content in the

ten

15

io

25

491

five

thirty

35

40

45

50

55

112

As 20% of the amount of absorbed bases in the soil absorbing complex, the flow rate of filtration is reduced by 90%.

The minimum mineralization of concentrated drainage water С „is calculated by the formula

J Na

 0.99-0.7 IgqNa Ca + Mg

where qNa is the content of exchangeable sodium in the soil absorbing complex% of the amount of absorbed bases; Na, Ca,

Mg is the content of sodium ions, calcium, magnesium, in drainage waters, mEq / l. With the most common Na / (Ca + Mg) ratio of 1 and 2, the minimum mineralization of the Sor is 12-6 g / l with a content of sodium ions of 50 and 67%, respectively.

The allowable salinity of drainage water Sor, suitable for accumulation in an evaporator pond, is determined by the formula

G - flWlEoS)

tP W

where W is the volume of the evaporation reservoir, m; EA - evaporability from 1 ha of water

the surface during the accumulation of drainage p, 1X of water in the reservoir-evaporator, m; S is the water surface area in the evaporator pond, ha. Due to the use of drainage water, the need for sodium salt is eliminated, which reduces the cost of formation of the impervious screen. In addition, the use of aggressive saline drainage water reduces the degree of environmental pollution, in particular, of water bodies into which drainage water is discharged.

Claims (1)

Invention Formula A method for creating an anti-filtration screen, preferably in a clay earth bed of an irrigation canal, including preparing and introducing a solution of salt into the ground and washing it out before forming an illuvial layer, and compaction of the soil, characterized in that, in order to reduce costs and pollution medium, the preparation of a salt solution уп oop1; 312491114 by concentrating the drainage water 67-50%, its introduction in the channel of the evaporation ponds to the minimum volume is repeatedly performed in non-mineralization equal to 6-12 g / l, the pre-channel periods of the channel, and the effluent content of sodium ions is correspondingly operational periods.