EA041024B1 - SOLUTION FOR SURFACE CLEANING FROM DEPOSITS OF DIFFERENT NATURE - Google Patents

Description

Technical field

The invention relates to the field of cleaning surfaces from deposits of various nature, namely to means for cleaning the surfaces of industrial equipment and can be used to remove deposits such as salt deposits, deposits of petroleum nature, including asphalt, resin and paraffin, resin deposits and deposits of a biological nature (bacterial deposits).

State of the art

The closest in the prior art is a solution for cleaning the surface of deposits of various nature (application No. 2016114065/02(022114)), containing hydrogen peroxide, complexone and water-soluble calixarene as the main components (selected as a prototype). This solution effectively removes deposits of various nature from metal, glass, ceramic and other coatings.

The disadvantage of this invention is the low efficiency in cleaning surfaces contaminated with deposits with a high content of organic matter. In addition, the above solution does not contain defoamers, which reduces the scope of its practical application, for example, the known solution is not recommended for use on objects with large volumes (from 1 m ³ ) of solutions due to abundant foaming, which can lead to a violation of the safety of the object .

Known solution for cleaning steel and brass surfaces of heat power equipment (SU 1805687, publ. 27.05.1995, IPC C23G 1/14, Sverdlovsk Research Institute of Chemical Engineering) containing, g/l: disodium salt of ethylenediaminetetraacetic acid (trilon B) 20, 0-50.0; hydrogen peroxide 15.0-30.0 and sodium hydroxide 3.5-18.0. This solution effectively removes iron and copper oxides without causing copper deposition on the surface of the equipment due to the content of sodium hydroxide.

The disadvantage of this method is the limited use on deposits of iron and copper oxide nature, as well as a sharp decrease in efficiency in the presence of organic deposits.

The invention is known. A solution for cleaning objects from uranium compounds and a cleaning method (RU 2138869, publ. 27.09.1999, IPC G21F 9/34, Dze Babcock and Wilcox Company, US). The invention relates to the removal of scale deviations, uranium contamination from equipment. The solution for cleaning uranium-contaminated units consists of a solvent, including ammonium carbonate, hydrogen peroxide, and a chelating agent selected from the group of carboxylic acids, in a certain ratio, and the solution has a pH of 9-9.5 and additionally contains a foaming agent. The cleaning method involves mixing the solution, causing it to foam in a tank located outside the contaminated unit and connected with it by liquid, the foamed solution is supplied with air or an inert gas to all voids of the contaminated unit, which allows the solution foam to condense and continuously wet the treated surfaces. EFFECT: invention makes it possible to effectively remove uranium contamination from the surfaces of process equipment and large-diameter pipes. Foam cleaning allows you to clean components such as ventilation networks.

The disadvantage of this method is increased foaming, which is undesirable when performing chemical cleaning of heat exchange equipment due to the possible distribution of reagents by parts of the foam.

A known method of using peroxides with complexing compounds in disinfectant compositions (RU 2360415 C1, CJSC NPP Biokhimmash (RU), publ. 10.07.2009, MPKA01 N25/22), which consists in the fact that for surface treatment, hydrogen peroxide immobilized on a complexing agent is used for disinfection . 1.5 kg of mechanically activated complexone is mixed with 5 kg of peroxide and diluted with 30 liters of water by adding a surfactant.

The disadvantage of this method is the narrow specificity of the application - the use only in disinfection, the absence of the use of metal oxidation inhibitors, the complexity of surface treatment.

Disclosure of invention

The general objective of the group of inventions is to create a new composition for effective cleaning of surfaces of equipment and products contaminated with deposits with a high content of organic substances, in particular, metal and/or non-metal surfaces, such as ceramic or polymer.

The general technical result of the group of inventions is to increase the efficiency of the solution (degree of cleaning) for cleaning surfaces contaminated with deposits with a high content of organic substances, while expanding the scope of its application.

The new invention has a significantly higher efficiency in comparison with previous inventions, including those containing hydrogen peroxide, as it allows the removal of deposits of heavy hydrocarbon fractions from oil production. A feature of these deposits is inertness with respect to chemical agents, therefore, in the present invention, the effect of the physical impact of the decomposition of peroxide compounds is enhanced by creating an alkaline environment in the working solution simultaneously with the use of directed catalysts.

The task and the required technical result are achieved by means of a solution for removing deposits of various nature, containing hydrogen peroxide, a catalyst for the decomposition of peroxide compounds, surfactants, complexone, water-soluble calixarene, defoamer and water in the following proportion, wt.%: hydrogen peroxide 2-35 ; peroxide decomposition catalyst 2-20; complexon 3-10; surfactant 0.1-5.0; defoamer 0.01-1.0; water-soluble calixarene 0.011.0; water is the rest. In this case, water-soluble chelating agents are used as a complexing agent, for example, polybasic salts of organic acids and derivatives of phosphorous acids.

The proposed solution as a catalyst for the decomposition of peroxide compounds contains hydroxides of alkali metals, compounds of metals with variable valence or mixtures thereof.

The proposed solution as a surfactant contains sulfonic acid, neonol, syntanol, lauryl sulfate or mixtures thereof.

The proposed solution as a defoamer contains a water-oil emulsion of polydimethylsiloxanes and other organosilicon compounds, as well as block copolymers based on ethylene oxide and propylene oxide.

In another alternative embodiment of the invention, the proposed solution additionally contains a stabilizer for peroxide compounds in an amount of 1-5 wt.%, where sodium hexametaphosphate, potassium phosphate, sodium tripolyphosphate are used as a stabilizer for peroxide compounds.

In another alternative embodiment of the invention, the proposed solution additionally contains a corrosion inhibitor in the amount of 0.5-2.5 wt. %.

The set task and the required technical result are also achieved by a concentrated component for obtaining the above solution containing a complexone, a water-soluble calixarene and a catalyst for the decomposition of peroxide compounds in the following ratio, wt.%: complexone 30-50; water-soluble calixarene 0.1-10, catalyst for the decomposition of peroxide compounds 2-20, water - the rest.

In one of the alternative embodiments of the invention, the proposed concentrated component additionally contains a corrosion inhibitor in an amount of 5-25 wt.%.

In yet another alternative embodiment of the invention, the proposed concentrated component additionally contains a stabilizer for peroxide compounds in an amount of 5-20 wt.%.

In another alternative embodiment of the invention, the proposed concentrated component additionally contains a surfactant in an amount of 3-30 wt.%.

In another alternative embodiment of the invention, the proposed concentrated component additionally contains a defoamer in an amount of 1-5 wt.%.

The set task and the required technical result are also achieved due to the method of preparing a solution for cleaning deposits of various nature, in which the proposed concentrated component is mixed with hydrogen peroxide and diluted with water.

The set task and the required technical result are also achieved due to the method of cleaning the surface with a solution for cleaning deposits of various nature, including the stage at which the specified surface is brought into contact with the solution proposed according to the invention, while the specified surface is a metal surface or a non-metallic surface.

The set task and the required technical result are also achieved due to the method of cleaning the surface from deposits of various nature, which consists in combining the mechanical, chemical and physico-chemical effects on the indicated deposits of the components of the cleaning solution obtained by the interaction of a concentrated component containing at least a decomposition catalyst peroxide compounds, a complexone and a water-soluble calixarene, with hydrogen peroxide, followed by dilution with water, leading to intense gas formation on the surface and inside the pores of said deposits, said surface being a metal surface or a non-metal surface.

The essence of the proposed cleaning technology lies in the combination of mechanical and chemical effects on deposits, as well as a combination of complexing and surface active properties in one molecule of the active component (water-soluble calixarene): one is complexing, the other is surface-active. The proposed technology uses the exothermic effect of the decomposition of peroxide compounds with intense gas formation on the surface and inside the deposits. This effect makes it possible not to heat the cleaning solution, since decomposition energy is used for these purposes. Also, the use of water-soluble calixarenes in combination with peroxide compounds contributes to the adsorption decrease in the strength of deposits. Intensive gas formation contributes to the loosening of deposits and their desorption from the surface of the equipment and products being cleaned. In combination with the use of water-soluble calixarenes, which combine in their property both complexing and surface-active properties with the possibility of forming micellar structures, a complete shift of equilibrium towards the dissolution of deposits, in particular, metal oxides, is achieved when cleaning metal surfaces.

In addition, in the proposed invention, the effect of the physical impact of the decomposition of peroxide compounds is enhanced by creating an alkaline environment in the working solution simultaneously with the use of directed catalysts. This contributes to a more pronounced intense gas generation on the surface and inside the pores of the deposits with the formation of bubbles with a radius of ^1.6x10'5 m to 2x10'3 m, maintaining a temperature of up to 250°C and a pressure of 0.1 to 16 MPa in the local decomposition zone, which allows you to act even on organic deposits inert to most chemical reagents in combination with the washing properties of the alkaline component.

Implementation of the invention

As already mentioned above, the essence of the proposed technology is the combination of mechanical, chemical and physico-chemical effects on deposits, as well as a combination of complexing and surface active properties in one molecule of the active component.

The decomposition of peroxide compounds is accompanied by abundant gas formation with the release of energy. The volume of gas released is proportional to the concentration of hydrogen peroxide. The exothermic effect of decomposition causes heating of the solution, which leads to an increase in the rate of manifestation of effects and the occurrence of chemical reactions directly in the pores of the deposits.

The composition of the cleaning composition (solution) includes hydrogen peroxide, a catalyst for the decomposition of peroxide compounds, a surfactant, a complexone, a water-soluble calixarene, a defoamer and water.

Hydrogen peroxide in the amount of 2-35 wt.% (depending on the concentration of the initial solution) provides the processes of gas formation by exothermic decomposition, which in turn has a destructive effect on deposits. The use of a composition with a percentage of less than 2 wt.% does not provide the desired effect (incomplete cleaning), the use of a composition with a percentage of more than 35 wt.% is not recommended, since in this case the effect of intense decomposition can have a destructive effect on the equipment. The concentration of hydrogen peroxide affects the volume of gas and the temperature in the pores of the deposits. By changing the concentration of the peroxide component, a given intensity of gas formation is achieved.

The catalyst for the decomposition of peroxide compounds in the amount of 2.0-20.0 wt.% (depending on the concentration of the initial solution), in the case of use in the form of alkali metal hydroxides, provides the necessary pH of the solution, has a destructive effect on organic deposits and passivates metal surfaces. For particularly difficult deposits, catalysts for the decomposition of peroxide compounds in the form of metal compounds with variable valence, for example, ions of copper, iron, chromium, nickel, manganese, etc., can be added to the composition of the cleaning composition.

In addition, it is possible to use compounds of metals with variable valence as catalysts for the decomposition of peroxide compounds without combination with alkali metal hydroxides while maintaining purification efficiency. Such use is possible, for example, in cases where the use of solutions containing alkaline components is difficult due to the nature of the material of the equipment. So, for example, aluminum alloys are subject to strong degradation, therefore, catalysts of metals with variable valence are used to apply the composition on equipment made of this material. At the same time, the preservation of the cleaning efficiency is achieved by maintaining the catalytic decomposition of peroxide compounds in the pores of the deposits.

As defoamers, water-oil emulsions of polydimethylsiloxanes and other organosilicon compounds, block copolymers based on ethylene oxide and propylene oxide in the amount of 0.01-1.0 wt.% are used. The use of a defoamer in an amount of less than 0.01 wt.% does not provide the effect of reducing the level of foam and foaming, and more than 1 wt.% does not affect the rate of defoaming. The presence in the composition of the proposed solution of such a component as a defoamer allows, in contrast to the prototype, to apply the solution on objects with large volumes (from 1 m ³ ) solutions due to the danger of violating the safety of objects.

The proposed solution contains a surfactant in an amount of 0.1-5 wt.%, which provides better wettability of the equipment surface, promotes deep penetration of the solution into the pores of deposits and emulsification of organic deposits in the solution.

As surfactants, nonionic surfactants are used - alkoxylates, alkyl glycosides, anionic surfactants carboxyethoxylates, phosphates and polyphosphates, sulfosuccinates, alkyl sulfates, alkyl ether sulfates. The use of surfactants provides an additional increase in the efficiency of cleaning the solution by reducing the surface tension at the interface liquid - solid (cleaning solution - deposits). This effect is due to the sorption of surfactant molecules on the sediment surface and is due to the similarity of the chemical nature of sediment molecules and surfactant molecules. The decrease in surface tension leads to better wettability of deposits with a cleaning composition, which entails an increase in the contact area of the solution with deposits. In addition, the above effect allows the solution to penetrate into the pores of the deposits, which leads to the possibility of delivering peroxide compounds to the pores of the deposits with subsequent decomposition. The selection of a surfactant is an important task and is decided individually depending on the nature of the deposits. The use of surfactants in concentrations less than 0.1% does not provide a wetting effect, more than 5% does not affect an additional increase in cleaning efficiency.

The complexone is used in the amount of 3-10 wt.%. As a complexone, it is possible to use water-soluble chelating agents, for example, sodium salts of polybasic organic acids or polybasic organic acids themselves, such as, for example, complexone 2, as well as derivatives of phosphonic acids, such as, for example, NTP, HEDP. The use of a complexone at a concentration of less than 3 wt.% does not provide the desired effect of complex formation, and at a concentration of more than 10 wt.%, the increase in the cost of the composition is not compensated by an increase in the washing action (the composition deteriorates according to the criterion of efficiency-cost).

Water-soluble calixarene of the general formula is used in an amount of 0.01-1.0 wt.%. Preferably, compounds of the general formula OH are used.

The use of water-soluble calixarenes of this structure makes it possible to effectively bind ions of heavy elements, including radioactive ones, forming strong complexes with them. You can use any structures of the specified composition. For heavy metal binding, compounds with 6-8 monomer units are preferable, since in this case the inner cavity of the molecule corresponds to the radius of heavy metals. The use of water-soluble calixarenes in concentrations lower than 0.01 wt.% does not provide a complexing effect, with an increase in concentration (more than 1.0 wt.%), no improvement in cleaning properties is observed.

The use of water-soluble derivatives of calixarenes, which combine in their property both complexing and surface-active properties of the composition, can significantly increase the purification efficiency. In particular, in the case of metal surfaces, metal ions are bound and transferred to the micellar phase (no previous proposal was made).

As a universal complexing agent, the most optimal is the use of derivatives of tetracarboxylic acids, for example, EDTA or its salts. These examples of specific acids are given for the purpose of illustrating the implementation of the group of the invention and do not limit the scope. These examples of acids should not be considered as limiting the scope of the proposed group of inventions, which is determined by the claims.

The composition can additionally be introduced stabilizer peroxide compounds in the amount of 1-5 wt.%. As this stabilizer, for example, sodium hexametaphosphate or analogous salts of phosphoric and polyphosphoric acids, such as, for example, sodium tripolyphosphate, are used. When using a stabilizer at a concentration of less than 1 wt.%, decomposition occurs like an avalanche and is not controlled, more than 5 wt.% - does not provide proper gas formation. The rate of gas evolution during the decomposition of peroxide compounds mainly depends on the ratio of the concentrations of the stabilizer and the catalyst for the decomposition of peroxide compounds.

To level the destructive effect of the cleaning composition directly on the surface of the equipment, appropriate inhibitors are additionally used in an amount of 0.5-2.5 wt.%. These substances form an insoluble durable layer on the surface, which protects the surface from the action of the active components of the solution. The use of an inhibitor at concentrations lower than 0.5 wt.% does not provide the proper inhibitory effect, and at a concentration of more than 2.5 wt.% leads to an unjustified increase in the cost of the composition. Captax (2-mercaptobenzothiazole), benzotriazole, tolyltriazole (a mixture of 4-methylbenzotriazole and 5-methylbenzotriazole), derivatives of pyridine and quinoline bases can be used as inhibitors.

The washing action is achieved by pumping the cleaning composition through the circuits of the equipment, or by placing the parts in a circulating bath.

To substantiate the quantitative content of reagents in an aqueous solution for cleaning deposits of metal and non-metal surfaces, sample examples were prepared (see Table 1), which were tested to evaluate the cleaning efficiency.

- 4 041024

Table 1. Examples (samples) of cleaning solutions

Composition, mass, % Examples 1 2 3 4 5 6 7 8 9 10 Hydrogen peroxide 1 25 thirty 5 15 thirty 5 15 thirty thirty Sodium hydroxide (catalyst for the decomposition of peroxide compounds) 0 0 5 5 10 10 15 15 thirty 40 EDTA 4 4 6 15 4 6 20 thirty 5 10 Defoamer 0.0 5 0.0 1 0.0 5 0.0 1 0.1 0.1 1 0.5 1 0.5 surfactant 0 0.1 0.1 1 1.5 2 2 3 5 7 Water soluble calixarene 5 2 0.0 1 5 0.1 0.1 3 0.1 0.1 0.1 Water ost ost ost ost ost ost ost ost ost ost

To obtain a solution (sample) according to example 1, a concentrated component containing complexone (EDTA), sodium hydroxide and water-soluble calixarene (6 monomer units) was mixed with a 36% hydrogen peroxide solution and diluted with water. The resulting cleaning solution had the following composition: hydrogen peroxide, sodium hydroxide, EDTA, water-soluble calixarene, surfactant, defoamer (water-oil emulsion of polydimethylsiloxanes) and water. The resulting solution was pumped through heat exchange equipment contaminated with oil residues (thermal decomposition products of heavy hydrocarbon fractions). The purity control was carried out by visual method and by the method of pressure difference at the inlet and outlet of the heat exchanger. The results of studies to evaluate the effectiveness of cleaning are given in table. 2.

Table 2. Results of studies on evaluating the efficiency of cleaning sample solutions

Cleaning performance on equipment with organic deposits Examples, No. of the compositions of the present invention 1 2 3 4 5 6 7 8 9 10 The presence of deposits after cleaning,% of the area The present invention 5 0 0 0 0 0 0 0 0 0 Prototype 10 20 thirty 10 10 20 15 10 20 thirty Cleaning time, hour The present invention 6 6 6 6 6 6 6 6 6 6 Prototype 8 8 8 8 8 8 8 8 8 8 Aggressive effect of the solution on the metal The present invention otte tvu em otte tvu em otte tvu em otte tvu em otte tvu em otte tvu em otte tvu em otte tvu em otte tvu em otte tvu em Prototype Parts otte tvu em otte tvu em otte tvu em otte tvu em otte tvu em Parts otte tvu em otte tvu em otte tvu em

In the first example, the presence of residual deposits was 5%, since in a solution of this type the content of peroxide compounds is not enough to carry out the reaction to the end (in this example, the content is 1%, in the rest it is more).

Solutions according to examples 1-10 were obtained analogously to example 1. The only difference is that NTF was used as a complexone according to example 2, according to example according to example 3 - EDTA, according to example 4 EDTA, according to example 5 - NTF, according to example 6 - OEDF, according to example 7 - EDTA, according to example 8 - EDTA, according to example 9 - OEDF, according to example 10 - NTF; as a catalyst for the decomposition of peroxide compounds in examples 3-10 used sodium hydroxide; as a surfactant in example 4 used sulfonol, in example 5 - OP-7, in example 6 - sodium lauryl sulfate, in example 7 - OP-10, in example 8 - a mixture of sulfonol and lauryl sulfate in a ratio of 1:1, in example 9 - sulfonol, in example 10 - a mixture of sulfonol and OP-10; as a defoamer in examples 1-5 used a water-oil emulsion of polydimethylsiloxanes, in examples 6-10 block copolymers of ethylene oxide.

The solutions obtained in examples 2-10 were tested and evaluated in a similar way according to example 1. The tests performed confirm the increase in the effectiveness of the proposed solution for cleaning deposits of organic nature, a feature of which is inertness with respect to chemical agents, while expanding its scope.

Although the present group of inventions has been described in detail with examples of options that seem to be preferred, it must be remembered that these embodiments of the invention

Claims (21)

are given for the purpose of illustrating the invention only. This description should not be construed as limiting the scope of the invention, since the described solution, the concentrated component for its preparation, the method for preparing the solution and the method for cleaning it can be changed by specialists in the field of chemistry and others aimed at adapting them to specific solution compositions. or situations, and not going beyond the scope of the attached claims of the group of inventions. A person skilled in the art will understand that within the scope of the invention, as defined by the claims, various variations and modifications are possible, including equivalent solutions. CLAIM 1. A solution for cleaning the surface from deposits of various nature, including deposits with a high content of organic substances, containing hydrogen peroxide, complexone, defoamer, water-soluble calixarene and water, in the following ratio, wt.%: hydrogen peroxide - 2-35; peroxide decomposition catalyst - 2-20; complexon - 3-10; surfactant - 0.1-5; defoamer - 0.01-1; water-soluble calixarene - 0.01-1; water is the rest. 2. The solution according to claim 1, in which, as a catalyst for the decomposition of peroxide compounds, it contains alkali metal hydroxides, compounds of metals with variable valence, or mixtures thereof. 3. The solution according to claim 1, which additionally contains a stabilizer for peroxide compounds in an amount of 1-5 wt.%. 4. The solution according to claim 1, which additionally contains a corrosion inhibitor in an amount of 0.5-2.5 wt.%. 5. The solution according to claim 1, which contains water-soluble chelating agents as a complexing agent, preferably polybasic salts of organic acids and derivatives of phosphorous acids. 6. The solution according to claim 3, which contains sodium hexametaphosphate, potassium phosphate, sodium tripolyphosphate as a stabilizer for the decomposition of peroxide compounds. 7. The solution according to claim 1, which contains sulfonol, neonol, sintanol, lauryl sulfate or a mixture thereof as a surfactant. 8. The solution according to claim 1, which contains, as a defoamer, an aqueous-oil emulsion of polydimethylsiloxanes and other organosilicon compounds, as well as block copolymers based on ethylene oxide and propylene oxide. 9. A concentrated component for preparing a solution for cleaning the surface from deposits of various nature, including deposits with a high content of organic substances, containing at least a complexone, a water-soluble calixarene, a catalyst for the decomposition of peroxide compounds and water in the following ratio, wt.%: complexone - 30-50; water-soluble calixarene - 0.1-10; peroxide decomposition catalyst - 2-20; water is the rest. 10. The concentrated component according to claim 9, which additionally contains a corrosion inhibitor in an amount of 5-25 wt. % 11. The concentrated component according to claim 9, which additionally contains a peroxide decomposition stabilizer in an amount of 5-20 wt.% 12. The concentrated component according to claim 9, which additionally contains a surfactant in an amount of 330 wt.%. 13. The concentrated component according to claim 9, which contains water-soluble chelating agents as a complexing agent, for example, polybasic salts of organic acids and derivatives of phosphorous acids. 14. A method for preparing a solution for cleaning a surface from deposits of various nature, including deposits with a high content of organic substances, including mixing a concentrated component with hydrogen peroxide, followed by dilution with water, which uses a concentrated component containing at least a complexone, a water-soluble calixarene, a decomposition catalyst peroxide compounds and water, in the following ratio, wt.%: complexone - 30-50; water-soluble calixarene - 0.1-10; peroxide decomposition catalyst - 2-20; water is the rest. - 6 041024 15. The method according to claim 14, in which water-soluble chelating agents, for example, polybasic salts of organic acids and derivatives of phosphorous acids, are used as the chelating agent. 16. The method of claim 14, wherein said surface is a metallic surface or a non-metallic surface. 17. A method for cleaning a surface from deposits of various nature, including deposits with a high content of organic substances, including the stage at which the surface to be cleaned is brought into contact with a solution containing hydrogen peroxide, a catalyst for the decomposition of peroxide compounds, a complexone, a surfactant, a defoamer, a water-soluble calixarene and water at the following ratio, May. %: hydrogen peroxide - 2-35; peroxide decomposition catalyst - 2-20; complex - 3-10; surfactant -0.1-5; defoamer - 0.01-1; water-soluble calixarene - 0.01-1; water is the rest. 18. The method according to claim 17, in which water-soluble chelating agents, for example, polybasic salts of organic acids and derivatives of phosphorous acids, are used as the chelating agent. 19. The method of claim 17, wherein said surface is a metallic surface or a non-metallic surface. 20. A method for cleaning a surface from deposits of various nature, including exposing said deposits to the components of a solution obtained by mixing a concentrated component with hydrogen peroxide and subsequent dilution with water, while using a concentrated component containing at least a complexone, a water-soluble calixarene, a catalyst for the decomposition of peroxide compounds and water in the following ratio, wt.%: complexone - 30-50; water-soluble calixarene - 0.1-10; peroxide decomposition catalyst - 2-20; water is the rest. 21. The cleaning method of claim 20, wherein said surface is a metal surface or a non-metal surface. ^8j) Eurasian Patent Organization, EAPO Russia, 109012, Moscow, Maly Cherkassky per., 2