The method of decontamination of solid surfaces

 

(57) Abstract:

The inventive decontamination of solid surfaces is carried out by creating contaminated by radioactive substances layer mechanical stresses generated under the influence of a shock wave generated by the explosion of explosives, after surface treatment received radioactive waste is collected and transported for disposal. Removing the contaminated layer is produced by undermining elongated, elongated cumulative or sheet quasar-charges that are laid out store on several similar frames in a certain way. Then either fill the shell charges, or moisten them based liquid explosive, set explosives and transfer frames in the store. Next, distribute the assemblies, and fix them to be treated surfaces, organize electroexplosive chain and undermine the charges. The choice of the charge depends on the material of the surface being cleaned, its strength characteristics and the desired thickness of the removed layer. The advantages of the invention are simplicity of implementation, low cost and safety.

1. The technical field to which the invention relates

The invention odnovariantnaya materials, made mostly of concrete, cement and bricks, such as the ceiling, walls, floors, other construction, as well as natural structures.

2. Art

Questions decontamination of various equipment and facilities considered in several works [1, 2].

Various methods of decontamination, among which we should mention the following:

- decontamination of steam mixtures, including using preejection sprayers;

- blasting decontamination;

- ultrasonic decontamination;

- electrical methods of decontamination;

dry decontamination methods (pastes, powders, compositions, forming a polymer film);

- combination of different ways.

To some extent, many methods assume the impact on polluted by radioactive substances layer solution of the reactants and removal of substances formed in the reaction. Range of reagents is very wide and many inventions describe their varieties. Most of the methods are related to the decontamination of metal surfaces and are connected with their clearance without destruction.

The well-known [3] the method of decontamination equipment and weapons, which consists in removing the total radioactive nuclides material use a variety of clay, having the property when dry to absorb radioactive isotopes.

A known method of purification from radioactive dust of the roof construction at the time of the Chernobyl accident, which is that on the roof surface was applied by pouring epoxy resin, which after polymerization was done together with the absorbed dust and sent for disposal.

In [4] the principles of universal technology before dismantling decontamination of the ship's nuclear power plants, equipment which are made of carbon steel, chrome-Nickel steels and titanium alloys. Technology is "sequential processing contour systems deformiruemymi solutions oxidation-reduction actions applying the principle of chemical transformation."

The deactivation of the production facilities, radioactive materials or waste considerable difficulties causes the cleaning of building or natural structures (floors, walls, ceilings) with deep pricefixing pollution caused by the diffusion of radioactive substances in materials of construction, their penetration into the micropores and microcracks surfaces, mechanically is selected and natural designs for their decontamination require other, than those mentioned above, the methods associated with the destruction and removal of the contaminated surface layer.

The solution of this problem is possible by mechanical impact on the surface layer of the shearing tool, the simplest representative of which is the chisel. Known [5] the method of decontamination of solid surfaces on the basis of concrete with the use of chisels. When using this method, the decontamination factor of the infinite, however, its efficiency is very low and correspondingly large dose uptakes, as it is assumed manual labor.

Known [2] the method of decontamination of solid surfaces processed objects by abrasive blowing. The essence of the method is based on the use of air jets after introducing the powder with abrasive action. The decontamination factor can reach 200-300. The disadvantages of the method is its low productivity (11 m2/h on concrete surfaces), the formation of secondary waste, heavy dusting, erosion damage to the surface.

Known [2] the method of decontamination by paleotsunami. The essence of the method consists in machining decontaminated surface brush with ignoramii (60-3003/h).

Among the disadvantages of the method should include the following: the complexity and danger of the method due to the constant driving of the suction device; deleted adhesion related contamination and adsorption-related and depth of contamination removal is not amenable; whence, very low coefficient of decontamination, not to exceed 20.

Known [2, 6-8] several methods for cleaning hard surfaces by creating thermal stresses sufficient for the destruction and removal of the surface layer.

Thus, in [6] described a method of disposal of asphalt coatings contaminated by radioactive substances. The method consists in the fact that the contaminated area on the glass cloth substrate is applied powder gomogenizirovannogo exothermic composition of a mixture of the ingredients, after which the composition is ignited, the plot is heated to soften and remove mechanically.

Method [7] decontamination of solid non-combustible surfaces is that decontaminated on the surface of the applied layer (thickness of 5 to 15 mm) powdered exothermic mixtures of the described composition, light and subsequently mechanically remove brasoveanu, concrete, asbestos and brick is achieved at temperatures above 1000oC.

Method [8] offers thermal stress in the surface layer to create an exposed surface exposed (located in a row) oxy-fuel torches in the zone of maximum temperature, floating along the surface with a certain velocity. Fixed: performance (23,7 m2/h) and the decontamination factor (123).

A number of inventions [9-11] propose for this problem to affect the surface layer of the shock wave (HC) generated upon excitation of the explosion. Due to exposure to UV narrowing of the contaminated outer surface layer and its shedding. Crumbled mass is then collected and removed. The decontamination factor approaches infinity.

Thus, in [9] shock wave is formed in the explosion are in contact with the cleaned surface charge of condensed explosives (he). The method has serious drawbacks [10], which is expressed in the limited operational capabilities. So, you want expensive organization of work associated with special storage, protection and transportation charges CC ka surfaces, especially curved; the explosion of condensed EXPLOSIVES formed chemically aggressive and highly toxic gases; possible denial of undermining part of the charge and the dam collapsed material; subsequent movement and evacuation of material possible accidental explosions with tragic consequences.

Method [10] and device [11] that implement this method, as CENTURIES suggest the use of a combustible gas mixture at the point of use mixing in vzryvosposobnosti the ratio of fuel gas and gas-oxidant.

Method [10], we adopted for the prototype has a number of advantages in comparison with the method [9]. So, cooking vzryvopodobnoe gas mixture is performed at the point of application; preparation of a mixture, as well as shipping and storage components are relatively safe procedures. Flammable gases have a relatively low cost, environmentally sound, characterized by high efficiency and productivity.

However, it has several disadvantages, among which we should mention the following: to implement the method requires a large number of different devices (booster pump, gas ventila spark plug), materials (radio frequency cable, durotomy and other hoses, localizing screen devices for sealing and fastening, balloons, glue); the complexity of installing screens and storage tanks, etc.

Method [12] describes the possibility of using technical explosions to minimize the amount of waste in the destruction of contaminated concrete equipment.

3. The invention

The essence of the invention is that the removal of the contaminated layer from hard surfaces is proposed to hold an explosive way using various quasar-charges, including extra long quasar-charges, a special case of which is detonating cord quasar-LH [13] , extra long cumulative quasar-charges (UCCS) [14-16] and leaf the quasar-charges.

The proposed method of decontaminating solid surfaces (walls, ceiling, floor, building or natural structures of stores, consisting in the removal of radioactively contaminated layer by a mechanical stress, the impact generated by the explosion of the explosive shock wave, the collection of radioactive waste, its transportation and disposal differs in that the removal of the ZAT on the choose source data required to complete the charge of certain shape and size, outside the store on several similar frames (substrates, substrates, assemblies) laid out a certain way and fix empty shell (main body) quasar-charge, fill shell (elongated or oblong shaped quasar-charges) or wet (soaked) base (sheet quasar-charges) liquid explosive (Kvazar-BB or WIMI on THE 7276-001-17582644-93), set explosives, carry frame store, distribute and fix them to be treated surfaces, organize electroexplosive chain and undermine the charges.

In the source data, which can select a desired charge, should be called the material of the surface being cleaned, its strength characteristics and the desired thickness of the removable layer.

The number of similar frames (substrates, Assembly) is determined by the size of the store; the size and weight of frame - comfort carry and install in a particular store.

The form of charges: KS-at (Kvazar-charge extended) - cylindrical;

UCCS (extended cumulative quasar-charge) is cylindrical with shaped notch or tolkova;

KS-l (Kvazar-charge sheet) list the specified form;

Quasar-RTA (detonating cord) - what is the thickness.

Empty shell quasar-charges laid on the frames in a certain way that ensures the task of removing the surface layer of a specified thickness all over the surface being cleaned, for example, in the form of a coil with a set spacing between parallel branches.

Frame (substrate, a base Assembly) can be collected from any material at hand, for example, from wood or plastic slats, metal corners, fabric material, etc.

Fixing the frames in the store to be cleaned surfaces is carried out, for example, by hanging on a pre-sealed in the walls and ceiling mounting elements, for example, hooks or nails.

If necessary, installed on the frames charges can be combined into a single charge.

At the same time undermining the mass of WIMI may not exceed the estimated mass is defined for this store maximum permissible explosive charge.

As blasting agents may use as a standard means of blasting and explosion-proof tools pullout quasar-SV.

Among the advantages of the proposed method include the following:

- easy, low cost and also if necessary, the charges of small diameters;

- WIMI (in contrast to the known solid industrial EXPLOSIVES) do not form in the atmosphere of radioactive aerosols, leading to the exposure of personnel;

- WIMI - HV liquid, produced by the use of two separately explosion-proof components;

- ability to cover all the surface of the vault;

- Assembly frames, layout and pinning empty shells quasar-charges, as well as sealing fasteners in ceilings and walls can lead not trained explosives workers;

- the possibility of reducing the time spent by the personnel in the hazardous area and thereby reduce the doses.

4. Information confirming the possibility of carrying out the invention

Work longer and longer cumulative quasar-charges repeatedly tested under production conditions, including, for the purpose of cutting metal.

Sources of information

1. Swedes B. N., Sedov C. M., Rybalchenko, I. L., I. Vlasov, N. Nuclear technology. Atomizdat, M., 1979, S. 336.

2. Simon A. D., Pikalov C. K., Decontamination. Atomizdat, M., 1994.

3. A. C. the USSR 1752119, G 21 F 9/34, 1990.

4. Konstantinov, E. A., Mochanov M. I., Normalization of the radiation situation in the reactor compartments atom of the volumes of decommissioning and disposal of nuclear submarines", 19-22 June 1995, M., 1995, S. 61.

5. A. C. the USSR 1538800, G 21 F 9/34, 1988.

6. RF patent 2086022, G 21 F 9/28, 1995.

7. RF patent 2114470, G 21 F 9/28, 1997.

8. RF patent 2025802, G 21 F 9/34, 1991.

9. The application of Germany 2745458, F 42 D 3/00, 1/08, F 42 1/02, G 21 F 9/00, publ. 1980.

10. RF patent 2146841, G 21 F 9/28, 9/34, F 42 D 3/00, 1998 prototype.

11. RF patent 2152094, G 21 F 9/34, 1998.

12. RF patent 2144707, G 21 F 9/00, B 09 At 3/00; F 42 D 3/00.

13. RF patent 2151758, 06, 5/04, F 42 3/087, 1998.

14. RF patent 2065559, F 42 1/02, 1993.

15. RF patent 2084806, F 42 1/02, F 42 D 3/00, 1995.

16. RF patent 2094741, F 42 1/02, 1995.

The method of decontamination of solid surfaces radioactive materials, consisting in removing the contaminated layer by a mechanical stress impact generated during the explosion of the explosive shock wave, the collection of radioactive waste, its transportation and disposal, characterized in that the removal of the contaminated layer is produced by undermining elongated, elongated cumulative or sheet quasar-charges, while depending on the material of the surface being cleaned, its strength characteristics and the desired thickness of the removed layer, select the shape and size of the charge, outside craniopathy based liquid explosive, WIMI, set explosive transfer Assembly in the store, distribute and strengthen them to be treated surfaces, organize electroexplosive chain and undermine the charges.

 

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