RU2325205C2 - Production method for air regeneration - Google Patents

Abstract

FIELD: fire-fighting components; production method of regenerating products.

SUBSTANCE: method includes interaction of hydrogen peroxide solution with potassium hydroxide at mole ratio l.5÷2.0. Before dehydration calcium hydroxide is introduced into the produced solution at mole ratio 1.0÷3.0 of hydrogen peroxide/calcium hydroxide. Temperature of reaction area should not exceed 50°C. Further dehydration is done by spraying the produced solution in drying agent flow.

EFFECT: production of regenerating product is ensuring longer time for protection of respiratory system and smaller value of aerodynamic resistance and temperature of gas-air mixture supplied to user.

1 dwg, 2 tbl, 9 ex

Description

The invention relates to methods for producing regenerative products used in air regeneration systems and isolating breathing apparatus (IDA) on chemically bound oxygen.

The use of regenerative products based on potassium superoxide in IDA cartridges is based on their release of oxygen and absorption of carbon dioxide exhaled by human air according to reactions 1 and 2

The conditions arising during the operation of the IDA (changes in the chemical composition of the product, temperature factor, etc.) often lead to melting and melting of the product, which complicates the diffusion of water vapor and carbon dioxide into the volume of chemisorbent granules. At the same time, there is a decrease in the gas - solid contact surface. All this in combination leads to the fact that the degree of product development in the IDA cartridge does not exceed 50-60%. Therefore, to ensure the necessary time for the protective action of the IDA equipped with such a regenerative product, one has to increase the overall dimensions of the product. In addition, the melting of the mixture of compounds formed during the work of the regenerative product dramatically increases the aerodynamic resistance to human respiration. This leads to the fact that children equipped with such regenerative products cannot use children, people suffering from respiratory diseases, etc.

Increasing the efficiency of the regenerative product and improving its operational characteristics is carried out both by changing the design of the cartridge of the breathing apparatus, and the composition of the regenerative product. For this, various additives are introduced into the composition of the regenerative product.

Traditionally, a regenerative product is made by mechanical mixing of the necessary components and subsequent molding of the resulting mixture into nozzles of various shapes (granules, tablets, etc.) placed in the cartridge of the breathing apparatus through which the regenerated air circulates.

A known method of producing a regenerative product [French patent No. 2521034, IPC B01J 20/04, 1983, French patent No. 2175652, IPC A62D 9/00, 1973], according to which its basis is potassium superoxide is obtained by the interaction of aqueous peroxide solutions hydrogen and potassium hydroxide. The obtained alkaline solution of hydrogen peroxide is sprayed onto the surface of a rotating metal drum at a temperature of about 160 ° C, where it is dehydrated and disproportioned to the intermediate adduct, potassium peroxide dihydroxyhydrate K ₂ O ₂ · 2H ₂ O ₂ . The resulting target product is removed using a scraper. The final product contains up to 85% KO ₂ , up to 15% KOH and up to 5% H ₂ O. The resulting product is mixed with calcium oxide in a mixer of bulk materials. The resulting mixture is molded in the form of plates, tablets, etc.

The disadvantage of this method is the high complexity, due to the need for the process at carefully controlled temperature and low productivity.

It should be specially noted that when working in a cartridge of an insulating breathing apparatus of a regenerative product of this composition due to the exothermic reaction 3 between calcium oxide and water

significantly increases the temperature of the gas-air mixture circulating in the system, and the melting of the products of chemical interaction leads to an increase in aerodynamic resistance to human breathing. This not only creates significant difficulties for the user of isolating breathing apparatus, but also in case of injury in an emergency (chest injury, etc.) can lead to death of a person.

The closest way to the same destination to the claimed method for the totality of signs is the following method for producing potassium superperoxide [application of Germany No. 310584, C01B 15/043, 1982]. In this method, potassium superoxide is obtained by reacting solutions of hydrogen peroxide and potassium hydroxide followed by dehydration of an alkaline solution of hydrogen peroxide and disproportionation of the intermediate adduct K ₂ O ₂ · 2H ₂ O _{2 by} spraying in a stream of a drying agent at a temperature of 130-250 ° C. As a drying agent, dry decarbonized gas (for example, air, nitrogen, etc.) is used. In this case, a solution of hydrogen peroxide with a concentration of from 50 to 85% and a solution of potassium hydroxide with a concentration of 50-60% are used. The molar ratio of N ₂ About ₂ / KOH = 1.3 ÷ 2.0. The final product contains up to 85% potassium peroxide, potassium hydroxide, water and impurities.

This method, in comparison with the previous one, is less labor intensive and is characterized by rather high productivity.

However, to obtain a regenerative product with the required characteristics and ready for use in an IDA cartridge, the obtained potassium superoxide containing potassium hydroxide and water, as well as in the methods of [French patent No. 2521034, IPC B01J 20/04, 1983, French patent No. 2175652, IPC A62D 9/00, 1973], should be subjected to further processing, which consists in introducing various additives into the resulting product. The introduction of additives can be carried out in these cases only by mechanical mixing, which fundamentally does not allow uniform distribution of the additive in the entire volume of the main substance due to the large mass difference between the base and the additive and, accordingly, to obtain a regenerative product with stable characteristics throughout the entire working time - oxygen evolution and carbon dioxide absorption. In addition, due to exothermic reactions 1, 2, 3 (especially due to reaction 3), partial or complete melting of the granules of the regenerative product occurs inside the cartridge of the respiratory apparatus. As a result, not only does the breathing resistance of the user increase and the permeability of gases through the product layer in the IDA cartridge decreases, but it is also quite possible due to a change in the shape and volume of the chemisorbent layer that, bypassing the regenerative product layer, new routes of passage of the circulating gas-air mixture occur. After that, the IDA ceases to fulfill its main function - to provide a person with oxygen necessary for breathing and remove CO ₂ from the air-gas mixture.

The objective of the invention is to improve the operational characteristics of the regenerative product and reduce the weight and size characteristics of the breathing apparatus while the time of the protective action is unchanged.

The technical result of the invention is to increase the efficiency of using the regenerative product and to reduce the aerodynamic resistance to breathing of the user.

The technical result is achieved in that in the method for producing a regenerative product based on KO ₂ , comprising reacting a solution of hydrogen peroxide and potassium hydroxide followed by dehydration of the obtained alkaline solution of hydrogen peroxide, the required amount of calcium hydroxide is introduced into the initial alkaline solution of hydrogen peroxide before dehydration.

This technique allows you to get a product containing potassium superoxide, potassium hydroxide, water and hydroxide and calcium peroxide in the form of structure-forming additives. In this case, calcium peroxide and hydroxide is introduced into the composition of the product directly during synthesis. This approach allows to obtain a regenerative product in which additives are uniformly distributed throughout its volume, i.e. the regenerative product obtained by this method has a homogeneous composition (and, therefore, properties) throughout the volume, which contributes to the course of the solid-phase reaction. The particle sizes of all components of the regenerative product are approximately the same. This improves the gas permeability inside the granules of the regenerative product. In addition, the introduction of a structure-forming additive directly in the synthesis process minimizes the number of technological stages in the production of a regenerative product (removing the stage of mechanical mixing of the components), which leads to a decrease in its cost and an increase in labor productivity.

A method of obtaining a regenerative product is as follows. An initial alkaline solution of hydrogen peroxide is prepared, for which a hydrogen peroxide solution, previously stabilized with either a soluble magnesium compound or any other suitable substance, with a concentration of 30 to 85% is mixed with a solution of potassium hydroxide with a concentration of 30-50% in a molar ratio of Н ₂ О ₂ / KOH = 1.5 ÷ 2.0. Potassium hydroxide can also be used in solid form. After that, calcium hydroxide is introduced into the solution either in solid form or in the form of a suspension. The molar ratio of H ₂ About ₂ / Ca (OH) ₂ = 1.0 ÷ 3.0. Using a stabilizer reduces the consumption of hydrogen peroxide. Also, to prevent decomposition of peroxide products when mixing the starting components, the process is carried out during cooling. The temperature in the reaction zone should not exceed 50 ° C, preferably the temperature is 10 ° C. The solution thus obtained is dispersed by the nozzle into the drying chamber in the direct flow of the pre-decarbonized drying agent. A typical drying chamber with a nozzle is used. As a drying agent, air or any inert gas, for example nitrogen, is used. Decarbonization of the drying agent is carried out using any carbon dioxide scavenger. To reduce the consumption of the drying agent, it can be preliminarily dehydrated by passing through regenerable water absorbers such as zeolite, silica gel, etc. The temperature of the drying agent varies from 120 to 300 ° C (preferably 180-230 ° C). At the end of dehydration, the solid product is separated from the gas mixture using a conventional battery cyclone and bag filter and collected in a special container.

The dehydration of the initial alkaline solution of hydrogen peroxide can be carried out in vacuum at a temperature of 30-150 ° C (preferably at 85-110 ° C) or in any other suitable way.

Thus obtained regenerative product, already ready for subsequent molding, has the following composition, wt.%:

potassium superoxide (KO ₂₎ 50-85 potassium hydroxide (KOH) 3-20 water (H ₂ O) 1-8 calcium peroxide (CaO ₂ ) 0.5-20 calcium hydroxide (Ca (OH) ₂ ) 0.5-15

Example 1

2 g of MgSO _{4 are} dissolved in 1215 ml of 30% hydrogen peroxide. The resulting solution was mixed with 733 ml of a 30% potassium hydroxide solution. Then was added 107 g of calcium hydroxide (molar ratio H ₂ O ₂ / KOH = 1.5, molar ratio H ₂ O ₂ / Ca (OH) ₂ = 3). The preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air, heated to a temperature of 120 ° C, is supplied. The flow rate of the solution through the nozzle is 8.7 ml / min. The consumption of the drying agent is 120 kg / h. 453 g of product are obtained containing 50.0% KO ₂ , 20.0% KOH, 13.8% CaO ₂ , 8.2% Ca (OH) ₂ and 8.0% H ₂ O.

Example 2

2.35 g of MgSO4 are dissolved in 797 ml of 50% hydrogen peroxide. The resulting solution was mixed with 375 ml of a 50% potassium hydroxide solution. Then was added 155 g of calcium hydroxide (molar ratio H ₂ O ₂ / KOH = 1.65, the molar ratio H ₂ O ₂ / Ca (OH) ₂ = 2.7). The preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air, heated to a temperature of 210 ° C, is supplied. The flow rate of the solution through the nozzle is 10.6 ml / min. The consumption of the drying agent is 102 kg / h. 497 g of product is obtained containing 64.1% KO ₂ , 3.0% KOH, 20.0% CaO ₂ , 8.7% Ca (OH) ₂ and 4.2% H ₂ O.

Example 3

1.7 g of MgSO _{4 are} dissolved in 572 ml of 50% hydrogen peroxide. The resulting solution was mixed with 375 ml of a 50% potassium hydroxide solution. Then was added 126 g of calcium hydroxide (molar ratio H ₂ O ₂ / KOH = 1.65, the molar ratio H ₂ O ₂ / Ca (OH) ₂ = 1). The preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air is heated, heated to a temperature of 210 ° C. The flow rate of the solution through the nozzle is 10.6 ml / min. The consumption of the drying agent is 102 kg / h. 472 g of product is obtained containing 58.8% KO ₂ , 10.2% KOH, 10.6% CaO ₂ , 14.3% Ca (OH) ₂ and 6.1% H ₂ O.

Example 4

2.3 g of MgSO _{4 are} dissolved in 784 ml of 50% hydrogen peroxide. The resulting solution was mixed with 375 ml of a 50% potassium hydroxide solution. Then was added 195 g of calcium hydroxide (molar ratio H ₂ O _2/2 = KON, the molar ratio H ₂ O ₂ / Ca (OH) ₂ = 1.4). The preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air, heated to a temperature of 210 ° C, is supplied. The flow rate of the solution through the nozzle is 10.6 ml / min. The consumption of the drying agent is 102 kg / h. Obtain 533 g of a product containing 58.5% KO ₂ , 4.4% KOH, 19.2% CaO ₂ , 15.0% Ca (OH) ₂ and 2.9% H ₂ O.

Example 5

1.8 g MgSO _{4 are} dissolved in 611 ml of 50% hydrogen peroxide. The resulting solution was mixed with 375 ml of a 50% potassium hydroxide solution. Then was added 89 g of calcium hydroxide (molar ratio H ₂ O ₂ / KOH = 1.65, the molar ratio H ₂ O ₂ / Ca (OH) ₂ = 2). The preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air, heated to a temperature of 210 ° C, is supplied. The flow rate of the solution through the nozzle is 10.6 ml / min. The consumption of the drying agent is 102 kg / h. 436 g of product are obtained containing 68% KO ₂ , 7.7% KOH, 11.6% CaO ₂ , 7.3% Ca (OH) ₂ and 5.4% H ₂ O.

Example 6

1.7 g of MgSO _{4 are} dissolved in 583 ml of 50% hydrogen peroxide. The resulting solution was mixed with 375 ml of a 50% potassium hydroxide solution. Then was added 59 g of calcium hydroxide (molar ratio H ₂ O ₂ / KOH = 1.65, the molar ratio H ₂ O ₂ / Ca (OH) ₂ = 2.4). The preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air, heated to a temperature of 210 ° C, is supplied. The flow rate of the solution through the nozzle is 10.6 ml / min. The consumption of the drying agent is 102 kg / h. 392 g of product are obtained containing 73.2% KO ₂ , 11.1% KOH, 8.6% CaO ₂ , 5.4% Ca (OH) ₂ and 1.7% H ₂ O.

Example 7

1.6 g of MgSO _{4 are} dissolved in 555 ml of 50% hydrogen peroxide. The resulting solution was mixed with 375 ml of a 50% potassium hydroxide solution. Then add 37 g of solid calcium hydroxide (molar ratio of H ₂ O ₂ / KOH = 1.65, molar ratio of H ₂ O ₂ / Ca (OH) ₂ = 2.8). Preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air, heated to a temperature of 210 ° C, is supplied. The flow rate of the solution through the nozzle is 10.6 ml / min. The consumption of the drying agent is 102 kg / h. 367 g of product are obtained containing 77.3% KO ₂ , 12.3% KOH, 6.2% CaO ₂ , 3.2% Ca (OH) ₂ and 1.0% H ₂ O.

Example 8

1.55 g of MgSO _{4 are} dissolved in 529 ml of 50% hydrogen peroxide. The resulting solution was mixed with 375 ml of a 50% potassium hydroxide solution. Thereafter, 25 g of solid calcium hydroxide (molar ratio H ₂ O ₂ / KOH = 1.65, the molar ratio H ₂ O ₂ / Ca (OH) ₂ = 2.8). The preparation of an alkaline solution of hydrogen peroxide is carried out in such a way that the temperature in the reaction zone does not exceed 50 ° C. After that, the resulting solution was dried in vacuum at 30-100 ° C for 3-5 hours. 385 g of product are obtained containing 80.6% KO ₂ , 9.4% KOH, 4.6% CaO ₂ , 1.7% Ca (OH) ₂ and 3.7% H ₂ O.

Example 9

1.45 g of MgSO _{4 are} dissolved in 248 ml of 85% hydrogen peroxide. The resulting solution was mixed with 315 g of solid 90% potassium hydroxide. After that, add 3.7 g of solid calcium hydroxide (molar, the ratio of N ₂ About ₂ / KOH = 1,65, the molar ratio of N ₂ About ₂ / Ca (OH) ₂ = 2). The alkaline solution of hydrogen peroxide is prepared in such a way that the temperature in the reaction zone does not exceed 50 ° C. After this, the solution is dispersed through a nozzle cooled to 10 ° C into a drying chamber, into which decarbonized dehydrated air is heated, heated to a temperature of 290 ° C. the solution through the nozzle is 13.3 ml / min. The consumption of the drying agent 91 kg / h 345 g of product is obtained containing 85% KO ₂ , 10.6% KOH, 0.5% CaO ₂ , 0.5% Ca (OH) ₂ and 3.4% H ₂ O.

The compositions of the regenerative products obtained in examples 1-9 are presented in table 1.

Table 1. Regenerative product Composition of the product, % KO ₂ KOH CaO ₂ Ca (OH) ₂ H ₂ O According to example 1 50,0 20,0 13.8 8.2 8.0 According to example 2 64.1 3.0 20,0 8.7 4.2 For example 3 58.8 10,2 10.6 14.3 6.1 For example 4 58.5 4.4 19.2 15.0 2.9 For example 5 68.0 7.7 11.6 7.3 5,4 For example 6 73,2 11.1 8.6 5,4 1.7 For example 7 77.3 12.3 6.2 3.2 1,0 For example 8 80.6 9,4 4.6 1.7 3,7 For example 9 85.0 10.6 0.5 0.5 3.4

Note. The composition of regenerative products may include up to 3% of various mass impurities (from the feedstock) that do not affect the quality characteristics of the product.

The regenerative product with a chemical composition according to examples 1-9 can be used in the form of tablets, granules, blocks, or a combination thereof, depending on the design of the cartridge of the breathing apparatus and the conditions of its operation. Operating conditions also affect the ratio of components in a regenerative product.

The regenerative product obtained by the present method, was tested in the cartridge of an insulating breathing apparatus on the installation of "Artificial lungs" (IL) under the following conditions:

- pulmonary ventilation 30.0 ± 1 l / min - volumetric supply of carbon dioxide 1.0 ± 0.03 L / min - humidity of the gas-air mixture,% 96-98 - oxygen consumption (exhaust from the installation) 1.14 ± 0.05 L / min - breathing rate 20 ± 0.5 min ^-1 - ambient temperature 20-25 ° C

Volumes of oxygen and carbon dioxide are indicated at 10 ° C and 101.3 kPa, pulmonary ventilation at 37 ° C and 101.3 kPa. For comparison with the regenerative products obtained by the claimed method (examples 1-9), under the same conditions, a regenerative product was tested specially made by the method described in the application of Germany No. 3105584. All regenerative products were in the form of tablets of the same size and density. The time of protective action was determined as the time from the start of the regenerative product to the moment when the concentration of CO ₂ in the flow of the gas-air mixture on the inspiration line of the IL installation reached 3%. The test results are presented in table 2 and in the drawing.

table 2 Test results of regenerative products on the installation "Artificial lungs". Composition of the product Product weight, g The time of protective action, min The amount of absorbed CO ₂ , l The amount of allocated O ₂ , l The maximum temperature on inspiration, ° С Maximum breathing resistance, mm water According to example 1 224 16.6 16.5 28,4 33.5 29th According to example 2 226 18.8 18.6 32,7 34.0 29th For example 3 223 17.3 17,2 30.3 34.5 29th For example 4 224 17,2 17.0 29.7 34.5 29th For example 5 221 19.8 19.6 35.3 35.0 thirty For example 6 225 22.1 22.1 37.9 35.0 thirty For example 7 223 21.5 21.3 36.6 35.0 thirty For example 8 223 22.6 22.4 38.7 35.5 thirty For example 9 225 16,4 16,2 26.1 33.5 29th Product according to the application of Germany No. 3105584. 226 16,0 15.8 25.3 36.5 33

The drawing shows the dependence of the aerodynamic resistance to breathing of the user from the operating time for the cartridge of the insulating breathing apparatus equipped with the product made according to the method described in the application of Germany No. 3105584 (curve 2) and the average change in this parameter for cartridges equipped with regenerative products according to examples 1-9 (curve 1). Since for all regenerative products according to examples 1-9 from table 1, the change in aerodynamic resistance to breathing by the user during IDA operation does not exceed 3%, the figure shows the change in the average value of this parameter.

The aerodynamic resistance of the gas-air mixture at the inspiration of the user is one of the main operational indicators of insulating breathing apparatus, largely determined by the composition and properties of the regenerative product. Reducing the value of this parameter not only creates more comfortable conditions for the user, but also significantly increases the circle of people who can use insulating breathing apparatus (children, people suffering from lung diseases, etc.).

As can be seen from the presented tabular and graphical data, regenerative products obtained by the claimed method provide, when operating in an insulating breathing apparatus cartridge, a longer protective action time with lower weight and size characteristics in comparison with a regenerative product made according to the method described in the application of Germany No. 3105584.

These positive, compared with the product made by the method described in the application of Germany No. 3105584, the parameters of the regenerative product are achieved due to the fact that, as a structure-forming additive, calcium hydroxide and calcium peroxide are introduced directly into the composition of the regenerative product. This allows you to more efficiently use the resource of the regenerative product and thereby increase the time of the protective action of the breathing apparatus with the same weight and size characteristics. In addition, the insulating breathing apparatus equipped with the proposed regenerative product has a lower value of aerodynamic resistance and lower temperature of the gas-air mixture supplied to the user by inhalation. This provides a more comfortable environment for the use of insulating breathing apparatus and expands the circle of people with physical ability to use IDA.

Claims (1)

A method of obtaining a regenerative product for insulating breathing apparatus, comprising the interaction of a solution of hydrogen peroxide and potassium hydroxide followed by dehydration of the obtained alkaline solution of hydrogen peroxide by spraying it in a stream of a drying agent, characterized in that calcium hydroxide is introduced into the initial alkaline solution of hydrogen peroxide, when this interaction is carried out at a molar ratio of hydrogen peroxide / potassium hydroxide 1.5 ÷ 2.0, hydrogen peroxide / calcium hydroxide 1.0 ÷ 3 , 0 and the temperature in the reaction zone not higher than 50 ° C.