The method of cleaning soil from radionuclides and device for its implementation

 

(57) Abstract:

The invention relates to the field of cleaning soil from radionuclides. The objective of the invention is to provide a method of cleaning soil from radionuclides, characterized by ease of recovery and recycling of radionuclides, relative cheapness, can be used in different types of terrain. The method consists in the fact that clay powder, is able to Sorb radionuclides, is formed into a porous pipe with bell - pipe-filters. Then the pipe-filters are burning, sort, test, package and transport in contaminated areas of soil. Contaminated sites determine the depth of radionuclides, make geodetic marking, digging trenches, align them, and laid in a trench the pipe-filters in the form of a closed drainage system below the level of occurrence of radionuclides in the soil and the soil. Connect the drainage system with wells traps radionuclides, which, in turn, connected to the channels, which discharge treated water in its natural channel, and covered trenches. After some time, determined by the amount of precipitation fell on the cleaned area, and sorbing ways again to complete the cleanup of contaminated soil. Wells-trap satisfied with a diameter of 1-2 m 2 S. and 1 C.p. f-crystals, 4 Il.

The invention relates to a method of cleaning contaminated soil.

In the Chernobyl disaster were contaminated a huge area of cultural lands.

In this regard, was invented many ways of cleaning soil from radionuclides.

Proposed by different authors are methods for removal of land from radionuclides can be divided into the four following groups:

1. Methods of biological treatment using biological objects - plants, bacteria, etc., with subsequent collection and disposal of biological substances.with. N 1771534, CL G 21 F 9/8, RF patent N 2010366, CL 5 G 21 F 9/18 and so on);

2. Methods chemical treatment by soil or soil of various chemical substances that neutralize and bind radionuclides (see and. C. N 1780426, CL 5 G 21 F 9/24, the application for the patent of the Russian Federation N 9201471 8/25 and so on);

3. Mechanical cleaning methods, by mechanical removal of contaminated soils or soil, and installation of various barriers (see RF patent N 2008734, CL 5 G 21 F 9/34, RF patent N 1806411, CL G 21 F 9/24);

4. their extraction and utilization (see A. C. N 1581084, CL 5 G 21 F 9/34, RF patent N 2025801, CL 5 G 21 F 9/12).

However, the known methods of cleaning soil from radionuclides are not without drawbacks.

The disadvantages of biological methods of cleaning soil from radionuclides are:

1. Impossibility in vast areas due to differences of soil types and soil (swamps, Sands, and so on) and different climatic conditions;

2. Difficulties with the collection of biological objects and their disposal;

3. Expensive.

The disadvantages of chemical methods of cleaning soil from radionuclides are:

1. Secondary chemical contamination of soil and ground;

2. High cost;

3. Difficulties with disposal of used chemicals, especially in wooded and marshy land.

The disadvantages of mechanical methods of cleaning contaminated land are:

1. The inability to remove all contaminated land;

2. High cost;

Disadvantages cleaning methods using sorbing substances are:

1. Secondary contamination of soil and ground;

2. Difficulties with the collection and disposal of sorbing sputtered substances, especially in wooded and Bolo is dionuclide in soils and grounds, water is, by partial dissolution and the water pressure is purely mechanical (see Chernobyl disaster: causes and consequences (expert opinion), part 4. "The consequences of the Chernobyl catastrophe for Ukraine and Russia", Chapter 4 "Geochemistry of technogenic radionuclides (hot particles) ChNPP and their environmental impact", Ed. by C. B. Nesterenko and other Minsk: Test, 1993, S. 40, 57, 66 - 75.

Known hollow, porous filters containing pores in the form of capillaries, purifying the water from dissolved radionuclides due to ion exchange at the molecular level with the filter material and due to the mechanical delay of radionuclide when filtering (see patent RU N 2060950 C1 6 C 02 F 1/18, 1996).

Also known is the method of assignment of the soil and groundwater buried in the land drainage pipes (see Century, Yasenetsky, N. To.Fenin. "Organization and technology of irrigation and drainage works". - M.: Kolos, 1975, S. 346 - 365. N. C. Argov and other "land Reclamation". - M.: Agropromizdat, 1991, S. 206 - 222).

In addition, known and apparatus for making tubular articles from powdered materials containing cone clip, elastic matrix, forming the core, base, liner, features, fix the PTO and the movable head plate with the supporting member, support frame with emphasis, the vibrator and the mechanisms of rotation and vertical movement of the core (see patent USSR N 1790493, class B 28 B 3/02, 1992).

Using these insights, the author offers a new method of cleaning soil from radionuclides.

The closest to the essence and the achieved effect is a method of cleaning soil and soil with plants (biological objects), which are the roots of (capillary-porous systems) absorb water from the soil, and with it the radionuclides and thereby purify the soil and the soil (see and.with. N 1771534, CL G 21 F 9/18).

In addition to the above disadvantages of the biological wastewater treatment plant, treatment plant has one significant drawback. This selectivity in the uptake of radionuclides. For example, some plants absorb radionuclides strontium and do not absorb radionuclides of cesium and Vice versa.

The objective of the invention is to provide a method of cleaning soil from radionuclides, characterized by ease of recovery and recycling of radionuclides, relative cheapness, the possibility of using different types of terrain (bolts, forests and so on) and in the vast areas of contaminated land, i.e., in chap who cleans the drainage systems of the pipe-filters, sorbing radionuclides, and pit-traps, walls also have the ability to Sorb radionuclides, which use the clay powder with a particle size of from 0.14 to 1.25 mm, a moisture content of 3 to 5 percent and form from it to install molding tubular products porous pipe with socket (pipe-filters), and then the pipe-filters are burning, sort, test, package and transport in contaminated areas of soil, contaminated sites determine the depth of radionuclides, make geodetic marking, digging trenches, align them, and laid in a trench the pipe-filters in the form of a closed drainage system, below the level of occurrence of radionuclides in soil and ground, connect the drainage system with wells traps radionuclides, which in turn connect with channels, which discharge treated water in its natural channel, and covered trenches, and then, after some time, determined by the amount of precipitation that fell on the cleaned area and absorptive capacity of the pipe-filters and material of the walls of the wells traps, remove the pipe-filters of trenches and wells traps the material of the walls and disposed of them, and then, if necessary, the CEC is granted diameter 1 - 2 m, and their walls are made of the inner and outer metal mesh, between which have a granular material, is able to Sorb radionuclides and to skip a large amount of water. The apparatus for forming tubular products on the forming core perform ledge, subject to the internal surface of the socket, and the elastic matrix is implemented with a recess, subject to the outer surface of the socket, while the installation is done without the mechanism of rotation of molding core, which caused the elastic coating.

An example of execution.

In Fig. 1 shows tubefilter, Fig. 2 shows a device for forming pipe-filters of Fig. 3 shows a portion of the drainage network in the plan, Fig. 4 shows a partial section of the drainage network vertically.

It is shown in Fig. 1 tubefilter consists of two structural elements - pipes 1 and socket 2.

The pipe-filters are manufactured in a range of sizes:

length, mm - 330 - 1500

inner diameter, m - 50 - 500

The bell perform standard sample ceramic sewer pipes.

The pore size of the pipe-filters perform within 5 - 10, 10 - 20, 20 - 50, 50 - 100, 100 - 200, 200 - 500 Ám. As Siri particles from 0.14 to 1.25 mm, humidity - 3 - 5%.

Forming pipe-filters that perform the installation of Fig. 2, is known from the patent of the USSR N 1790493, class B 28 B 3/02, 1992, containing cone clip, elastic matrix, forming the core, base, liner, elements, fixing the elastic matrix, the loading device, a frame structure, installed on it the loading device and the movable head plate with the supporting member, the supporting frame with the stop, the vibrator and the mechanisms of rotation and vertical movement of the core (Fig. 2 not indicated).

A distinctive feature of the setup (Fig. 2) used for forming pipe-filters, from the well-known is that on the forming core is made protrusion 3, subject to the internal surface of the socket, and the elastic matrix is made with a recess 4, surrounding the outer surface of the bell. In addition to forming the core installation caused resilient floor 5, with the specified installation completed without rotation mechanism forming the core.

Applying an elastic coating 5 on the forming core installation, you need to eliminate flattening of the particles of the soft powders on the solid surface of the core, and, in the context of the Oia, molding clay core caused by the lack of powder clay reinforcing fibers.

After forming the pipe-filters are fired at a temperature of 1000 to 1350oC with a holding time of 1 to 2 hours. Then the pipe-filters sorted (raspakovyvat and feel special technique), labeled and packaged. Further, the pipe-filters transported to the place of laying - on terrain contaminated by radionuclides. At the specified location and determine the depth of radionuclides and do surveying the layout of the trenches. The depth of the radionuclides in the soil and the soil is determined by multiple drill holes, exploration excavated from soil pits and soil. Next, dig a trench known machines, for example, CDG-55, CDG-80, produced alignment strip and consistently investing in the socket of one tubefilter pipe end of the second tubefilter, spread the drainage network (Fig. 3). Drainage network stack below the level of occurrence of radionuclides in soil or ground (Fig. 4). The size of the trench depth from the level of occurrence of radionuclides is equal to the diameter of the pipe-filters.

In the process of laying drainage network connect with wells traps 6 (Fig. 3), which in turn connect with channels 7, ommodating and outer metal mesh, between which have a granular material, is able to Sorb radionuclides and to skip a large amount of water, for example, silicon-containing adsorbent.

After laying drainage network, wells traps 6 (Fig. 3) and outlet channels 7, fall asleep trench 8 (Fig. 4), and thus, the cleaning system is ready for operation.

The proposed drainage system cleaning soil from radioactive contamination is as follows.

The principle of operation is shown in Fig. 4, where the position 9 shows the contaminated soil or ground position 1 shows tubefilter, position 10 shows clean soil or soil, the arrows show the movement of water and radionuclides to the pipe-filters 1, the broken line shows the level of deposits of radionuclides.

Water in the form of rain or melt water from getting into the ground or soil, partially dissolving partially capturing particulate radionuclides, the path of least resistance reaches pipe-filters. Being filtered through the walls of the pipe-filters, water is cleared from radionuclides and channels composed of pipe-filters 1 reaches wells traps 6 (Fig. 3). In wells-traps 6 water, again being filtered through the walls, additionally is not shown).

By the passage of some time, a year or two since the laying of the drainage network, which is determined depending on the amount of precipitation in the area, and absorptive capacity of the pipe-filters and the walls of the wells traps, remove from the soil or soil worn out the pipe-filters, remove the sorbent material of the walls of the wells traps and measure the degree of contamination of the soil.

If the degree of contamination of the soil of the land after cleaning as described above meets sanitary standards, purified from radionuclides plot of land is transferred to the user.

If the soil and the soil after the first cleaning cycle does not meet sanitary norms on the level of contamination by radionuclides, the above described cycle cleanup of soil and ground repeat again.

Worn out, contaminated with radionuclides pipe-filters and the material of the walls of the wells traps transported to the place of their disposal.

The proposed method, as malariafree soil, can be applied to various soils and soils (swamps, Sands, and so on), i.e., in comparison with known biological way (treatment plant) expansion is litate the catastrophe at the Chernobyl NPP.

In addition, the application of the proposed method in comparison with the known biological reduces the cost of the cleanup of the soil, because it does not require expenses for its operation.

It should also be noted the versatility of the proposed method in comparison with known biological, because plants absorb radionuclides selectively, for example, absorb radionuclides strontium and do not absorb radionuclides of cesium, and the proposed pipe-filters of the proposed method is detained almost all types of radionuclides.

Next, the proposed method of cleaning soils from radionuclides in comparison with known biological speeds up the cleaning process, because it allows one to pass through the pipe-filters and wells traps a large number of contaminated groundwater and soil water.

Therefore, new features, namely: - clean up of soil and soil by cleaning contaminated soil and groundwater by the drainage systems of the pipe-filters and water traps, creating a new filter design (pipe-filters with a bell), the use and improvement of the known device for a new purpose - fabrication of pipe-filters, replacement of traditional drainage tube in meliorativnoye the device canals create a positive effect and, thus, are essential.

1. The method of cleaning soil from radionuclides by groundwater remediation, dissolving and transporting radionuclides in the soil and the soil, characterized in that soil and clean soil drainage systems of the pipe-filters, sorbing radionuclides, and pit-traps, walls also have the ability to Sorb radionuclides, which use the clay powder with a particle size of from 0.14 to 1.25 mm, a moisture content of 3 to 5% and molded out of it on the installation forming tubular articles porous pipe with bell - pipe-filters, and then the pipe-filters are burning, sort, test, Packed and transported in contaminated areas of soil, contaminated sites determine the depth of radionuclides, make geodetic marking, digging trenches, align them, and laid in a trench the pipe-filters in the form of a closed drainage system below the level of occurrence of radionuclides in soil and ground, connect the drainage system with wells traps radionuclides, which, in turn, connected to the channels, which discharge treated water in its natural channel, and covered trenches, and after etorousa ability pipe-filters and material of the walls of the wells traps, remove the pipe-filters of trenches and wells traps the material of the walls and disposed of them, and then, if necessary, the cycle is repeated again until the full cleaning contamination sites soil.

2. Cleaning method under item 1, characterized in that the wells traps satisfied with diameter of 1 - 2 m, and their walls are made of the inner and outer metal mesh, between which have a granular material, is able to Sorb radionuclides and to skip a large amount of water.

3. Device for forming tubular articles containing cone clip, elastic matrix, forming the core, base, liner, elements, fixing the elastic matrix, the loading device, a frame structure is installed on it the loading device and the movable head plate with the supporting member, the supporting frame with emphasis, vibrator, mechanism for vertical movement of the core, characterized in that for forming the core caused the elastic cover and the ledge, subject to the internal surface of the socket, and the elastic matrix is made with a recess, subject to the outer surface of the bell.

 

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