RU2539205C2 - Method of creation of cut-off curtains with filter windows - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: method comprises development and filling of the trench 1 with impervious material from geomembrane 2. Before lowering into the trench 1 of the geomembrane 2 the additional plate of geomembrane 4 is glued to it 3. The space between the geomembrane 2 and the additional plate 4 is filled with sorbing-filter material 5 to form a drainage system of rectangular shape. In the main 2 and the additional plate 4 of the geomembrane on opposite sides near the places of gluing 3 of the additional plate 4 the filter windows 6 are made. At the inlet to the drainage system from the side of groundwater dam 7 in the additional plate 4 of the geomembrane and in the main geomembrane 2, in the place of location of the filter windows 6, in the soil to a depth of the trench the receiving 8 and the outlet 9 niches are located, which are filled with coarse filter material 10.

EFFECT: improvement of efficiency of purification of contaminated groundwater flow and increase in the volume of its passing.

1 dwg

Description

The invention relates to the field of protection of groundwater and open watercourses and is intended to intercept contaminated ground flows from storage ponds of liquid wastes, industrial wastes, effluents of livestock complexes, oil and oil products leaks from oil storage facilities, gas stations, removal of toxic chemicals from irrigation fields such as pesticides , herbicides, phosphorus, potassium, etc.

Groundwater pollution is not limited to the area of industrial enterprises, waste storage facilities, etc., but spreads downstream to a distance of 20-30 km or more from the source of pollution. Pollutants are carried out by a soil filtration stream to open watercourses (river, pond, pond, etc.).

The most harmful are “long-living” radioactive elements with increased ability to move in water (strontium-90, uranium, radium-226, cesium and others).

A known method of creating anti-filtration curtains (PFZ) in the soil from hardening aggregates made in a continuous way, i.e. development and filling of the trench with antifiltration material (PFM) without dividing into sections. Underground structures constructed by the “wall in the ground” method. / Ed. Cand. tech. Sciences V.M. Zubkova. -L.: Stroyizdat, Leningrad Branch, 1977, S. 93-101.

The disadvantage of this method is that when creating an impermeable curtain against the path of movement of a polluted stream, water is created which causes a rise in the level of groundwater, waterlogging, etc.

There are various methods of constructing underground impenetrable curtains constructed by the wall in soil method, including those involving the use of methods and structures for enclosing foundation pits during the construction of underground structures, while regulating groundwater reserves (SU 1668557 A1, 08.08.1991, RU 2046883 C1, 27.10. 1995, RU 2056475 C1, 03.20.1996, RU 2244785 C1, 01.20.2005). In these methods, a trench is developed from the day surface of the soil, it is filled with a thixotropic solution, which is subsequently replaced by a hardening solution or monolithic structures, or prefabricated elements to the entire depth of the trench.

The disadvantages of the known methods and designs are the large material consumption and the complexity of the erection of the curtain, which leads to an increase in the duration of the work, the lack of reliability of the curtain during its construction in flooded soils due to the formation of cracks in the curtain during sealing joints of prefabricated elements.

There is a method of protecting water resources using horizontal (inter-layer) anti-filter curtains and the technology of their construction (patent RU, No. 2347034, IPC EV 3/16, published on February 20, 2009). The essence of the method under consideration: they pass a vertical trunk within the boundaries of the lithological “window”, drill from it at the marks of the curtain being constructed fans of horizontal horizontal wells, the depth of which is limited by the aquifer zone, injection of fixing solutions through the wells, as a result, a horizontal waterproof curtain separates the aquifer into two parts.

The disadvantages of this method are:

- limited area of application due to the use of this method only within the boundaries of the lithological "window", ie local conditions, the diameter of the curtain can reach 250-300 m, which is determined by the depth of the beam drainage wells;

- the impossibility of creating an underground impenetrable curtain around an object under construction or protecting the environment from underground technological processes.

Closest to this invention is a method of creating anti-filter curtains with filter windows (Patent RU No. 2301862, IPC EV 3/16, published June 27, 2007), including the development and filling of the trench with anti-filter material with windows filled with sorbent-filtering or deactivating - filtering material.

The disadvantage of this method is:

- the complexity of the removable cartridge;

- a small volume of sorbent-filtering material and, accordingly, a small transmitted volume of the filtrate through the windows;

- high consumption of hardening impermeable material backfilled into the trench;

- the possibility of violating the integrity of the "walls in the ground" due to subsidence of the ground.

The objective of the proposed method is:

- increased productivity when installing geomembranes in a trench;

- the use of the trench itself for filling the sorbent-filter layer between the main and additional panels;

- creation of filter windows to increase the volume of the pass and clean the polluted stream through the filter windows;

- the possibility of filtering-sorbing walls with intake and exhaust windows around the sources of pollution;

- the possibility of multilayer filling of sorbent-filtering material with various mechanical and physical properties.

The technical result to which this invention is directed is that when filling the space between the geomembrane and the additional cloth from the geomembrane with sorbent-filtering material, and when creating the main and additional cloth of the geomembrane of filtering windows, the volume of the passage and cleaning of the contaminated stream through filter windows. In addition, the proposed method of creating anti-filter curtains with filter windows provides an increase in the efficiency of cleaning contaminated soil flow.

In the proposed method, the main and additional geomembrane panels on opposite sides, near the places of gluing the additional panels, carry out filter windows, due to which the contaminated stream is cleaned and the volume of its passage increases.

In FIG. 1 shows a method of creating impervious curtains with filter windows (A-A - a rectangular drainage system;

BB - receiving niche filled with large filtering material;

B-B - exit niche).

The method of creating anti-filter curtains with filter windows is as follows.

After the development of trench 1, the antifiltration material from the geomembrane 2 is lowered into the required depth into it. Before lowering into the trench 1 of the geomembrane 2, an additional 3 cloth from the geomembrane 4 is glued to it, the space between the geomembrane 2 and the additional cloth of the geomembrane 4 is filled with sorbent-filtering material 5, s the formation of a rectangular drainage system. At the same time, filter windows 6 are made in the main geomembrane 2 and the additional geomembrane 4 panel on opposite sides near the places of gluing 3 of the additional geomembrane 4 panel.

At the entrance to the drainage system of a rectangular shape, from the side of the groundwater backwater 7 in the additional cloth from the geomembrane 4 and in the main geomembrane 2, in the area where the filter windows 6 are located, in the soil a reception 8 and an exit niche 9 are filled with large filtering material 10.

Claims (2)

1. A method of creating impervious curtains with filter windows, including the development and filling of the trench with antifiltration material from the geomembrane, characterized in that before lowering the geomembrane into the trench, an additional geomembrane cloth is glued to it, the space between the geomembrane and the additional cloth is filled with a sorbent-filtering material with rectangular drainage system, with the main and additional geomembrane panels on opposite sides near places gluing additional panels perform filter windows. 2. The method according to p. 1, characterized in that at the entrance to the drainage system of a rectangular shape from the side of the groundwater in the additional cloth of the geomembrane and in the main geomembrane, in the area of the filter windows, in the soil to the depth of the trench arrange a receiving and output niche, which are filled with large filtering material.