RU2532174C1 - Method of purifying air mixture in surgery and maternity blocks from pathogenic microflora, highly volatile organic and carcinogenic substances and recovering oxygen in closed rooms - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: air mixture is forced into a purification system and purified step by step: first, the air mixture passes through carbon-fabric filter, then through a carbon filter and a chemisorptive filter; further, the mixture is fed into a cavity adapted to create turbulent air flow, which is fitted with monochromatic emitters in the ultraviolet and blue regions; after light exposure, the mixture is purified by passing through a calcium peroxide filter while entering the next cavity which is adapted to create turbulent air flow, and then purified by a carbon-chemisorptive filter and a cotton-fabric filter.

EFFECT: multi-step purification.

3 cl, 1 dwg

Description

The invention relates to medicine, namely to a method for cleaning the air mixture in surgical and maternity units from pathogenic microflora, volatile organic and carcinogenic substances, as well as oxygen regeneration at the time of surgery and during obstetric care in enclosed spaces.

Currently, some methods are used for air purification in surgical and maternity units. The basis here is built-in air conditioners and stationary air purification systems that only supply air to clean rooms designed for operations and other activities, thereby reducing only the concentration of undesirable harmful substances in the premises. And since the air conditioning filter almost never changes, the accumulated filter residues, like the filter itself, become the habitat of microbes. Therefore, air conditioning itself becomes a threat to human health. But a particularly dangerous threat to human health are viruses, bacteria, staphylococci and streptococci, which can also be carried by the indoor air.

Also, a negative effect (carcinogenic effect) is exerted by many aromatic chemicals (resins, cokes, gases), some simple chemical compounds (alcohols, vinyl chloride, chloromethyl ethers, formaldehydes), as well as inorganic compounds and substances, such as lead, arsenic, chromium, cadmium. Especially a lot of these substances are in the atmosphere of large cities and central highways. The use of “oxygen masks” during the operation period has a positive effect, but after the operation the patient is returned to the regular ward where he can get a background disease due to the presence of pathogenic microflora in the ward at a time when the patient’s immunity is close to the minimum.

Currently, there is a method of air purification, which is carried out in devices of the AEROLIFE type of Russian production, where the supply, exhaust, and supply and recirculation air are cleaned in the premises. According to the manufacturer’s technical documentation, the installation includes: a coarse dust filter, an electrostatic unit, a polarized HEPA filter with an aerosol deposition system, two stages of photocatalytic filters and a coal-catalytic filter, where the coarse filter removes large dust particles from the air; an electrostatic unit - charging aerosols and fine dust particles, a polarized HEPA filter - delays aerosols and tiny dust particles up to 0.01 microns and on which unpleasant odors, viruses and bacteria can be adsorbed; two-stage photocatalytic filter - where at the first stage, all gas-phase air pollutants (unpleasant odors, toxic gases, allergens, pathogenic viruses, bacteria, fungal spores, etc.) are adsorbed on the surface of the photocatalyst and under the influence of ultraviolet radiation (range A) decompose to harmless constituents (up to carbon dioxide and water). In the process, pollutants do not accumulate on the filter, but are completely decomposed. In the second stage, it effectively captures, mineralizes and destroys gas-phase pollutants that are not destroyed in the first stage of the photocatalytic unit. The carbon-catalytic filter prevents the passage of harmful substances by adsorbing them on the surface of the adsorbent. The technology of joint work of the adsorption and photocatalytic filter allows you to make the adsorbent catalytically active and regenerated during operation. Filter service life - 5 years. The proportion of purification from pathogenic microflora and fine aerosols is 99.9%. (http://www.vozdyx.ru/?m=50&t=27, patent No. 8634, 12.16.1998).

The disadvantages of this device are:

1. With such a design of the device, where there is no forced supply of the air mixture, which reduces its efficiency and air filtration rate, therefore, its performance and declared efficiency are extremely doubtful, and the statements “... The technology of combined operation of the adsorption and photocatalytic filter allows you to make the adsorbent catalytically active and regenerated in the course of work ”simply do not succumb to any laws of chemistry and physics.

2. Ultraviolet radiation of the "A" range (wavelength 315-400 nm) cannot ensure the decomposition of "... unpleasant odors, toxic gases, allergens, pathogenic viruses, bacteria, fungal spores ..." into carbon dioxide and water, as the manufacturer claims, in view of low energy ability of the given radiation of the ultraviolet spectrum to the destruction of intermolecular bonds and especially intramolecular.

Also known is a method of air purification by irradiating the air mixture with ultraviolet radiation of the "C" range (wavelength 220-280 nm). Ultraviolet irradiators are designed to disinfect indoor air in order to prevent bacterial contamination of air and indoor surfaces in the absence of people. Therefore, the disadvantage of this method is the use of this method in the complete absence of people, which is simply unacceptable during operations or obstetrics. And this method is only a preparatory stage for cleaning the premises or the next stage - after operations.

As an analogue, the method of cleaning the air mixture in (NPK "AVERS", utility model patent No. 81684) is taken, where the method of cleaning the air mixture from solid and drip-liquid particles is carried out using carbon and chemisorption filters, and the reduction of virulence or destruction of pathogenic microflora is carried out through the use of hard UV radiation in the wavelength range of 205-315 nm, an intense blue light spectrum in the range of 430-480 nm, as well as infrared radiation in the range of 850-1600 nm. This method has low efficiency when used in medical institutions.

The objective of the invention is to develop a new method for continuous cleaning of the air mixture in the surgical and maternity units, as well as enriching it with oxygen due to the chemisorption of carbon dioxide and water vapor.

Achievable technical result of the invention is a multi-stage cleaning supplied by the compressor of the air mixture, namely:

- purification from fine particles and aerosols with a carbon-fabric filter;

- adsorption by carbon and chemisorption filters of gases, vapors of alcohols, ethers and other organic compounds;

- photo exposure to pathogenic microflora and fine gas molecules with hard ultraviolet radiation (wavelengths 200-290 nm) and a monochromatic spectrum of blue light (wavelengths 430-470 nm), which reduces their virulence and destruction of the membranes of microorganisms and their protoplasm, as well as activation of organic molecules;

- chemisorption of carbon dioxide (CO ₂ ) and water vapor with calcium peroxide (CaO ₂ ) with the release of atomic and molecular oxygen;

- turbulent mixing of pathogenic microflora and their toxins with atomic oxygen, their disinfection and oxidation;

- adsorption by carbon and chemisorption filters of gases, vapors of alcohols, ethers and other organic compounds;

- purification from fine particles of coal and calcium peroxide with a cotton-cloth filter.

The proposed method implements a new approach in the cleaning, disinfection and regeneration of oxygen indoors due to oxygen exhaled by humans and oxygen, as well as the removal of volatile organic substances (vapors of alcohols, ethers, etc.) from the atmosphere by chemisorption filters, where catalysis and effective disinfection of pathogenic microflora provides photo exposure to ultraviolet and blue light spectra, together with atomic oxygen resulting from the chemical reaction of CO ₂ with calcium peroxide.

The method of purification of the air mixture in surgical and maternity units from pathogenic microflora, volatile organic and carcinogenic substances and oxygen regeneration in enclosed spaces, is that the air mixture, supplied by force to the cleaning system, from fine dust and aerosols is carried out using a carbon-fabric filter and from vapors of organic and volatile compounds - coal and chemisorption filters, the reduction of virulence and photocatalysis of organic substances and microflora is carried out on at the same time ultraviolet (wavelengths 200-290 nm) and blue (wavelengths 430-470 nm) monochromatic emitters, and chemisorption of carbon dioxide and water vapor is ensured by using a filter of calcium peroxide, which in this case releases atomic and molecular oxygen into the air mixture and during turbulent mixing of pathogenic microflora and their toxins with atomic oxygen, disinfection and oxidation occur, as well as enrichment of the air mixture with oxygen molecules, while the organic compounds in the air mixture The ions are adsorbed by a secondary carbon-chemisorption filter, while the fine particles of coal and calcium peroxide are filtered by a cotton-cloth filter.

The developed method is illustrated by the scheme (Fig. A):

1. Carbon fabric filter;

2. Carbon filter No. 1;

3. Chemisorption filter No. 1;

4. A cavity for creating turbulence of the mixture and its irradiation No. 1;

5. Ultraviolet and blue monochromatic emitters;

6. A chemisorption filter made of calcium peroxide;

7. A cavity for creating turbulence of the mixture and its irradiation No. 2;

8. Carbon filter No. 2;

9. Chemisorption filter No. 2;

10. Cotton fabric filter.

The method can be carried out as follows.

With the help of a low-noise compressor, an air mixture is supplied, which is located in the surgical or maternity units.

The air mixture sequentially passes the following types of cleaning.

When the mixture is supplied, primary cleaning of fine particles and aerosols is carried out by using a carbon-fabric filter (1). The air mixture contained in these rooms includes vapors of esters, alcohols, aldehydes and other organic compounds, as well as fine particles of solids, droplet-liquid aerosols, as well as pathogenic microflora, consisting of respiratory and influenza viruses, staphylococci, streptococci and pathogenic bacteria . Air purification from gases, vapors of alcohols, ethers and other organic compounds occurs as a result of adsorption by carbon (2) and chemisorption filters (3).

Then, in a cavity (4) configured to create a turbulent air flow and in which monochromatic emitters (5) of ultraviolet (wavelengths 200-290 nm) and blue (wavelengths 430-470 nm) ranges are installed, photo exposure to pathogenic microflora is performed and finely dispersed gas molecules, which leads to a decrease in virulence and destruction of the membranes of microorganisms and their protoplasm, as well as the activation of organic molecules.

With further passage of the air mixture, it passes through a filter of calcium peroxide (6), as a result of which it chemically reacts with carbon dioxide and water vapor, with the release of atomic and molecular oxygen. Then the enriched mixture enters the next cavity.

This cavity (7) is also configured to create a turbulent flow of the air mixture. In this cavity, the pathogenic microflora and their toxins are disinfected and oxidized with atomic oxygen, and the air mixture is enriched with oxygen molecules. The remaining vapors of alcohols, ethers and other organic compounds are adsorbed on a carbon filter (8) or enter into a chemical reaction on a chemisorption filter (9), i.e. at this stage the purification is carried out on a carbon-chemisorption filter.

The final cleaning of fine particles of coal and calcium peroxide is carried out with a cotton-cloth filter (10).

The air mixture, purified from fine particles and aerosols, organic substances, pathogenic microflora, their toxins and enriched with oxygen, returns to the room again. In this case, the enrichment of the air mixture with oxygen is carried out in proportion to the content of exhaled carbon dioxide, which is very important for enclosed spaces. Filtering the air mixture, with a room volume of 200-300 m ³ , is carried out 10 times in 60 minutes.

When implementing the method provides for replaceable cartridges with the mentioned filters, with a frequency of not more than 1 time per month, their disposal must be carried out in accordance with sanitary standards and rules in the Russian Federation.

This is achieved due to the following factors:

1. The carbon-fabric filter, according to its technical characteristics, provides for complete filtration from fine particles to 0.1 μm, as well as the absorption of aerosols with a carbon filter (GOST 12.4.011-89).

2. Adsorption of gases and volatile alcohols and ethers is carried out on an activated carbon surface due to the Van der Waals force (Adsorption and Chemisorption - Wikipedia).

3. When exposed to intense blue light (wavelength 440-460 nm), light quanta are actively absorbed by the vapors of ammonia, formalin and carbon monoxide, turning into an active state, which contributes to a significant increase in adsorption and chemisorption by activated carbon (by 300%), while the temperature of the sorbent increases from 76 ° C to 137 ° C.

4. UV radiation in the wavelength range 205-315 nm has a high antimicrobial effect, and radiation with wavelengths less than 200 nm forms an allotropic modification of oxygen in the air - ozone, which in turn also has strong antimicrobial properties (Wasserman A.L. et al. "Ultraviolet radiation in the prevention of infectious diseases" M .: Medicine. 2003).

The blue spectrum of visible light also has a strong antibacterial effect, and is also a strong activator of organometallic compounds (protoplasm) with their subsequent destruction upon exposure to UV radiation or chemisorbents (Antimicrobical Agents and Chemotherapy, 2005, No. 49, pp. 1391-1396).

5. In the interaction:

6. Atomic oxygen in its antibacterial properties is 2.5 times more effective than UV rays and 300 times more than chlorine and chloramines (Razumovsky S.D. Oxygen - elementary forms and properties. M., 1979, Thermodynamic properties of oxygen. M. , 1981).

The proposed method is an effective way to clean the air mixture in enclosed spaces from fine particles and aerosols, vapors of alcohols, ethers and other volatile organic compounds, as well as from pathogenic microflora and oxygen regeneration due to the absorption of carbon dioxide and calcium peroxide and the release of atomic and molecular oxygen . In this method, where filtering, photoactivation of sorbed objects, adsorption, chemisorption, disinfection and oxygen regeneration due to human CO ₂ and H ₂ O vapors are simultaneously carried out, there are currently no competitive analogues.

This method will be in demand in enclosed spaces without additional influx of atmospheric air. The developed method for the synthesis of calcium peroxide will contribute to the low cost of the main components of filtration plants, which will be based on this method.

Application examples of the method

In the laboratory “Personal Protective Equipment”, OJSC “Sorbent” (Perm), tests were performed to filter the air of an enclosed laboratory room containing fine particles, formaldehyde vapors and volatile organic compounds, the pollution atmosphere was set by evaporation and using a 1000 W domestic fan .

The composition of the air mixture:

formaldehyde - 2.5 mg / l;

diethyl ether - 7.6 mg / l;

ethyl alcohol - 4.3 mg / l;

ammonia - 2.1 mg / l;

CO ₂ - 1.1% of the total volume of the air mixture indoors;

O ₂ - 16.82%;

fine particles (up to 0.2 μm) - household dust mixed with KNO ₃ and K ₂ SO ₄ - 3.4 mg / l.

After filtering the proposed method for 15 minutes, the composition of the air mixture was as follows:

formaldehyde - 0.01 mg / l;

diethyl ether - less than 0.01 mg / l;

ethyl alcohol - traces;

ammonia - traces;

СО ₂ - 0.03% of the total volume of the air mixture indoors;

O ₂ - 24.82%;

fine particles (up to 0.2 microns) - household dust mixed with KNO ₃ and K ₂ SO ₄ - traces.

At the Department of Microbiology and at the Central Research Laboratory of the State Institution “Novosibirsk State Medical University”, tests were conducted to filter the air of a closed surgical room (after the operation - 4 hours continuously) containing pairs of volatile organic compounds and pathogenic microflora - streptococci, Staphylococcus aureus, pneumococci, Pseudomonas aeruginosa, Escherichia coli (34 to 178 colonies were detected, the nutrient medium was chicken protein and agar-agar).

The composition of the air mixture:

diethyl ether - 2.3 mg / l;

ethyl alcohol - 2.5 mg / l;

ammonia - 0.9. mg / l;

CO ₂ - 0.12% of the total volume of the air mixture indoors;

O ₂ - 15.64%.

After filtering by the developed method for 20 minutes, the results of the values of the air mixture pollution were as follows:

diethyl ether - 0.02 mg / l;

ethyl alcohol - 0.01 mg / l;

ammonia - traces;

СО ₂ - 0.02% of the total volume of the air mixture indoors;

O ₂ - 26.17%,

colonies of streptococci, Staphylococcus aureus, pneumococci, Pseudomonas aeruginosa, Escherichia coli in the air mixture were absent (nutrient medium chicken protein and agar-agar).

When conducting an experiment in a ward with 6 patients, on the basis of 57 city clinical hospital in Moscow, DS pneumonia, tracheobronchitis, chronic obstructive pulmonary bronchitis, possible background diseases - influenza and other respiratory viral diseases, the following results were obtained after air treatment using the proposed method, the following results were obtained .

All patients said that they breathe better after air ventilation. The dream has become deeper. Patients stopped waking up at night.

In 4 patients the cough became noticeably less frequent, in all patients the “barking” cough disappeared. After taking the medicine, all patients feel more energetic and cheerful, on the 3rd day the drowsiness in the morning hours disappeared. The terms of hospitalization decreased, on average, by 25-40%.

On the walls near the floor, mold and fungus disappeared, which could not be bred for more than 5 years, with annual repairs.

Air purification, without airing, was carried out 4 times a day for 20 minutes, and at bedtime - 40 minutes.

In the next room with 7 patients, such changes were not observed, at the time of the outbreak of the flu, all patients had the flu, the hospitalization period increased by 7-9 days.

Thus, the proposed method has the following advantages:

1. The method is convenient to use, highly effective in the cleaning, disinfection and regeneration of oxygen in confined spaces, which is necessary for maternity and surgical units, without additional equipment for supply and exhaust equipment.

2. Does not require additional disinfection of the room from pathogenic microflora, the possibility of continuous disinfection in the presence of people.

3. Easy to execute, safe and low cost.

4. The possibility of use in surgery, obstetric care, intensive care, tuberculosis dispensaries and other rooms that require a high degree of purity and protection from pathogenic microflora.

Claims (3)

1. The method of purification of the air mixture in surgical and maternity units from pathogenic microflora, volatile organic and carcinogenic substances and oxygen regeneration in enclosed spaces, which consists in the fact that the air mixture is forcibly supplied to the cleaning system and is gradually cleaned: first, the air mixture passes through coal a fabric filter, then through carbon and chemisorption filters, after which the mixture enters a cavity configured to create a turbulent air flow in which chromatic emitters of the ultraviolet and blue ranges, after photo-exposure, the mixture is cleaned by passing through a filter of calcium peroxide, entering the next cavity, made with the possibility of creating a turbulent air flow, and is cleaned by a carbon chemisorption filter and a cotton-cloth filter. 2. The method according to claim 1, in which monochromatic emitters of the ultraviolet range with a wavelength of 200-290 nm are used. 3. The method according to claim 1, in which monochromatic emitters of the blue range with a wavelength of 430-470 nm are used.

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