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Use of ozone
Ozone (chemical formula O3), also known as active oxygen, triplet oxygen, super oxygen and oxygen enrichment, widely exists in the ozone layer 20 kilometers away from the earth's surface. Because it can absorb most ultraviolet rays from solar radiation and protect life on earth from harm, it has attracted worldwide attention.
There is still a trace of ozone in the air (the content is 0.0 1 ~ 0.04 ppm), which is the highest in waterfalls, seaside and forest areas. The ozone concentration in general forest areas can reach 0.0 1~0.04ppm, which is produced by the way that ultraviolet rays of sunlight are condensed by water droplets and oxygen in water droplets reacts to become ozone. Especially when it thunders in rainy days, lightning will produce a lot of ozone. These trace ozone in the air effectively inhibited the abnormal reproduction of bacteria and molds in nature and maintained the ecological balance.
1785, when the Germans used the motor, they found that there was an odor when the motor was discharged. 1840, German scientist Schonbein identified this odor as O3 and named it ozone. Since then, European scientists have taken the lead in studying the characteristics and functions of ozone. After discovering the broad-spectrum bactericidal effect, they began to apply it to industrial production. Among them, a Swedish beef company used ozone to keep beef fresh, starting from 1870.
/kloc-in the 0/9th century, people realized the strong oxidation of ozone, and found that ozone had oxidation effects on wood, straw, starch, plant pigment, natural rubber, fat, animal and vegetable oil, alcohol and so on. 1868, Germany? Gebbers (Germany? Gebeth) obtained the first patent of ozone application technology, which used ozone to oxidize coal tar mixture into products suitable for coatings and paints. 1873, ozone was used in sugar production and flax bleaching in Europe. Over the past 100 years, the application of ozone has penetrated into many fields and made great contributions to the development of human production technology. The application of ozone can be divided into four areas according to its use: water quality treatment, chemical oxidation, food processing and preservation, and medical treatment. Application research and equipment development in various fields have reached a fairly high level. Independent ozone technology industries and departments have been formed in the world, and the International Ozone Association (IOA) established by 1973 is located in Canada. The Association holds an international conference every two years to exchange papers and reports on the development of ozone technology in various countries. In developed countries, IOA regional organizations are generally established for academic exchanges.
After World War II, the international ozone application technology has made great progress. First of all, in 1902, the first large-scale water plant using ozone to treat water quality was established in paderborn, Germany, which pioneered the treatment of ozone water. Now there are thousands of ozone water plants in the world. The application of ozone in waterworks in Europe, America, Japan, Canada and other countries has reached a universal level. Using ozone instead of chlorine to disinfect and purify tap water can be directly drunk. Almost all mineral water and pure water manufacturers are equipped with ozone equipment. In the early 1970s, the United States began to use ozone to treat domestic sewage, the main purpose of which was to sterilize, remove pollutants, decolorize and so on, so as to meet the discharge standards. In Japan, sewage is treated by ozone and used as reclaimed water in water-deficient areas. The United States, Japan, Germany, France and other countries have established large-scale ozone sewage treatment plants in recent years. Secondly, the industrial application of ozone has also been very common, mainly used in chemical, petroleum, paper, textile, pharmaceutical and perfume industries. The application of food industry is more popular. 1904, Europe used ozone to preserve milk, meat products, cheese, protein and other foods. In the late 1930s, 80% of oocyte cryopreservation warehouses in the United States were equipped with ozone generators. After World War II, Europe, the United States and Japan used ozone in the storage, manufacture and transportation of food, fruits and vegetables. In medical treatment, Japan used ozone for physical therapy during World War II, while Russia used strong air (ozonated air) to strengthen athletes' physique. At present, there are many medical uses in the world, such as air disinfection in wards and operating rooms, ozone water disinfection of medical instruments, ozone treatment of dental diseases (oral surgery and maintaining oral sterility), ozone combined with radiotherapy treatment of cancer, drinking ozone water treatment of gynecological diseases, ozone gas injection treatment of fistula and hemorrhoids, varicose veins and so on. In terms of health care, it is popular in Japan and Taiwan Province Province to inhale strong air (air with low ozone concentration) to strengthen the body and shower the body with ozone water for sterilization and beauty. The popular high-tech beauty is actually the application of ozone beauty. In major international competitions, swimming pools and diving pool also use ozone sterilization to protect the health of athletes.
Scientific research has found that ozone molecules are extremely unstable, which can decompose to produce monoatomic oxygen (O) and hydroxyl (OH) with strong oxidizing ability, quickly destroy the internal structure of bacteria, viruses and other microorganisms, and have a strong killing effect on various pathogenic microorganisms! The sterilization effect of ozone is much better than that of chlorine, the sterilization speed is 200 ~ 3000 times faster than that of chlorine, and it can be decomposed into oxygen by itself, leaving no harmful substances and causing no secondary pollution.
The representative field of ozone technology industrialization is drinking water treatment engineering. Especially after 1970s, after the carcinogenicity of halogenated organic compounds was confirmed, all countries strictly restricted the use and emission of chlorine. Ozone technology has become the first choice to replace chlorine in drinking water treatment projects in developed countries. Up to now, more than 10000 ozone water plants have been put into operation in the world, reaching the popularization level in Europe. The United States, Canada, Japan and other countries are vigorously developing and applying ozone drinking water treatment projects. For example, the United States uses ozone technology in water purification projects, and thousands of large water plants use ozone disinfection to popularize cancer-free drinking water for the people. The United States also uses ozone to purify the surrounding waters. In the world-wide shrimp epidemic in the early 1990s, the United States stood out and gained a bumper harvest and rewards. The ozone sterilization and purification process has been completely popularized in bottled drinking water in Europe and America. In 1980s and 1990s, several ozone treatment water plants were also established in China, Beijing, Shanghai and Fushun, among which Beijing Tiancun Water Plant was the largest. Some large domestic enterprises actively adopt ozone disinfection technology in their own water supply plants, such as Daqing, Shengli Oilfield, Yanshan Petrochemical and other ozone water plants are running. In recent years, China's bottled drinking water industry has adopted ozone sterilization and purification project, which has been recognized by technical supervision and health and epidemic prevention departments. It is difficult for bottled water factories without ozone equipment to compete in the market.
At the end of 1990s, the United Nations put the protection of the ozone layer and the improvement of the living environment of human beings on the agenda of the United Nations General Assembly for many times, and formulated corresponding international conventions, demanding that ozone be regarded as an important substance for environmental protection for everyone to know. Therefore, the status of ozone as an environmental protection industry has been promoted as never before, and its technological development and industrial process have a good social foundation.
Mechanism and characteristics of ozone disinfection
First, the ozone disinfection mechanism
Ozone is the second strongest oxidant known to mankind after fluorine, which can react with bacteria, viruses and other microorganisms at a certain concentration. Ozone is unstable because of its high energy, and its molecular structure is changeable at normal temperature and pressure, and it is quickly decomposed into oxygen (O2) and a single oxygen atom (O). Mono-oxygen (O) has a strong activity, and has a strong oxidation effect on bacteria, viruses, heavy metals and other microorganisms.
Ozone can oxidize and decompose glucose oxidase, which is necessary for glucose oxidation in bacteria, and directly interact with bacteria and viruses, destroying their organelles and ribonucleic acids, and decomposing macromolecules such as DNA, RNA, protein, lipids and polysaccharides, thus destroying the metabolic growth and reproduction process of bacteria. It can also penetrate the cell membrane tissue, invade the cell membrane, and act on the outer membrane lipoprotein and inner lipopolysaccharide, so that the cell permeability is distorted, resulting in cell lysis and death, and the genetic genes, parasitic strains, parasitic virus particles, bacteriophages, mycoplasma and pyrogen (endotoxin) in dead bacteria are dissolved and denatured and die. Looking at the principle of aseptic technology on microorganisms, it can be divided into three types: bacteriostasis, sterilization and bacteriolysis. Ozone sterilization belongs to lysozyme, which can "completely and permanently destroy all microorganisms inside the object"
Second, the characteristics of ozone disinfection
Compared with conventional disinfection and sterilization methods, ozone disinfection and sterilization methods have the following characteristics.
(1) Efficient ozone disinfection takes air as the medium, without adding any other auxiliary materials and additives. A certain amount of ozone is generated during disinfection, which spreads evenly in a relatively sealed environment and has good inclusiveness. It overcomes the feature that there are many dead corners in ultraviolet disinfection, and can achieve the purpose of omni-directional, rapid and efficient disinfection and sterilization. In addition, it has a broad bactericidal spectrum, and can kill various viruses such as bacterial propagules, spores, hepatitis A and B viruses, various pneumonia viruses, fungi and protozoa, as well as Botox, toxins and rickettsia, and also has a strong effect of removing mold, fishy smell and peculiar smell.
(2) The unique advantage of ozone as a disinfectant lies in its rapid and natural decomposition into oxygen. Ozone is produced by using oxygen in the air. In the process of disinfection and oxidation, excess oxygen (O) combines into oxygen molecules (O2) after 30min, and there is no residue, which solves the problem that disinfectants are easy to be polluted again and saves the trouble of cleaning again after disinfection.
(3) Convenient ozone sterilizers are generally installed in clean rooms or air purification systems or sterilization equipment (such as ozone sterilization cabinets, transmission windows, etc.). ). Set the start-up and running time of the sterilizer according to the sterilization concentration and time verified by debugging, which is convenient to operate and use. Ozone disinfection can be started regularly every day.
(4) Economy: According to the application of ozone disinfection in many pharmaceutical industries and medical and health units, ozone disinfection method has great economic and social benefits compared with other methods. Today, with the rapid development of industry, environmental protection is particularly important, and ozone disinfection avoids the secondary pollution caused by other disinfection methods, which benefits forever with one investment.
Application of air disinfection and sterilization
First, indoor air pollution is more serious than outdoor air pollution, but there is no effective product to solve this problem. Because the decoration of family rooms and the installation of air conditioners have become very popular, the environment that is warm in winter and cool in summer and the improvement of sealing degree have created conditions for the reproduction of bacteria, such as air pollution after decoration, pollution of water heaters (gas) and gas stoves, odor emitted by the elderly or patients, odor of toilets, respiratory metabolism of family members, visitors, etc. , all bring pollution to the air of the family. Therefore, it is very necessary for families to use ozone for air purification.
Second, industrial sites, food, fruit and vegetable processing workshops, pharmaceutical processing workshops, etc. These manufacturing sites, which are closely related to human life, are indispensable for disinfection and sterilization, which is an extremely broad ozone application market. In addition, ozone can also remove the air pollution in printing and chemical workshops, the fishy smell of fish products and the odor of aquaculture plants. It can also be used for plague prevention and health care of breeding birds (chicks). Used for air disinfection in vegetable greenhouses and can replace pesticides.
Third, food preservation ozone is very popular in Europe, America, Japan and other countries, and is used for the preservation of food, fruits, vegetables and so on. It has penetrated into all aspects of production, storage and transportation, and it is rare in China. Ozone is used to keep fresh, and its main application markets are cold storage, constant temperature storage, ships and transport vehicles, which can keep meat food from deteriorating for a long time; It can also keep fruits and vegetables intact during storage, and enhance the aroma of strawberries, cherries, grapes and other berries on the basis of preservation. Its biggest advantage is that it can store inventory under high humidity, with less weight loss and high storage quality.
Four, the securities trading hall, conference hall, waiting room (computer room), hotels, dance halls, nightclubs, hotels, etc. It is highly mobile in public places. In addition to polluted air, the cross-infection of viruses and bacteria also directly threatens people's health, especially hepatitis B virus, cold virus and all kinds of pneumonia that make people talk about it. However, there is no effective disinfection and sterilization method in these places at present, which has no impact on the ozone product market.
5. Hospitals are places where patients gather, and the occurrence and spread of viruses and bacteria are serious. In order to ensure the recovery of patients and avoid cross infection, the hospital has strict disinfection and sterilization procedures and systems. At present, the disinfection and sterilization methods in hospitals mainly include:
(1) The disadvantages of ultraviolet sterilization in indoor air disinfection are slow sterilization speed, high cost and dead angle. Ultraviolet rays can cause harm to human skin, so the use requirements are very strict.
(2) Potassium permanganate, peracetic acid solution, burning, steaming and boiling are common methods for disinfection of medical devices; There are some problems in disinfection of instruments and supplies, such as secondary pollution during storage, which affects the service life.
(3) Large-scale extermination methods are mostly used to splash Soviet water, which makes the hospital have a particularly unpleasant smell.
(4) Using ozone products has the advantages of rapidity, thoroughness, tasteless, no side effects, convenience and low cost.
Application of water treatment
I. Drinking water treatment
Ozone is widely used, and the most successful field is the treatment of drinking water.
At present, China's water pollution mainly comes from industrial wastewater, pesticides and fertilizers, domestic wastewater, corrosion of water pipe network and suspended solids, microorganisms, bacterial viruses and algae in high-rise secondary water supply. The water we finally drink can't meet the national standard (GB5749), and the items that often exceed the standard are: total bacteria, Escherichia coli, iron, manganese, heavy metals, chloroform, algae, chromaticity, turbidity and so on. Even if qualified, there are still secondary pollution problems such as corrosion and rust of water pipes and bacteria in water tanks. Boiled raw water can only be partially sterilized. Chlorination disinfection and chlorine dioxide and sodium hypochlorite disinfection promoted in recent years cannot directly drink tap water. Because chlorine disinfection will produce chlorine derivatives and cause secondary pollution, trihalomethane is a direct carcinogen, which has been gradually eliminated in drinking water treatment in Europe and America. Therefore, in 1996, the Ministry of Health issued a document requiring that the secondary water supply must be equipped with disinfection facilities, and the self-provided wells of some units must be allowed to be used only when the water quality reaches the standard. At present, the disinfection products of secondary water supply are only selected from chlorine dioxide, sodium hypochlorite and ozone generating equipment, and ozone water treatment has obvious competitive advantages. At present, all kinds of popular household water purifiers and purified water on the market only filter particles and impurities in the water, but cannot be completely disinfected. Moreover, while filtering impurities, it also filters out organic substances necessary for human body, such as calcium, iron and zinc. Drinking this soft water for a long time is harmful to human body.
Second, the swimming pool water treatment
Ozone technology is very mature for swimming water treatment technology, and is widely used in Europe and America. Almost all swimming pools in international competitions are treated with ozone technology. China's swimming water standard requires that the number of bacteria < 1000, coliform group < 100 and turbidity < 5. Due to technical and economic reasons, chlorine, bleaching powder, copper sulfate and other disinfection methods are mainly used at present. These methods not only meet the water quality standards, but also cause eye-catching adverse reactions such as water quality and skin irritation, especially in the use of liquid chlorine. When the water quality reaches the standard, ozone technology does not have the above defects.
Third, aquaculture water treatment
Aquaculture water is rich in organic matter, and the water quality is prone to problems. Bacteria and viruses are very harmful to fish and shrimp. In recent years, many aquaculture plants in China's coastal areas have stopped production, reduced production and abandoned a lot, making it difficult to develop artificial aquaculture. In aquaculture water treatment, ozone can not only sterilize and inhibit the infection and spread of virus to fish and shrimp, but also degrade organic matter, reduce chemical oxygen demand (COD) and biochemical oxygen demand (BOD) and improve water quality due to its coagulant aid. It has been reported abroad that treating aquaculture water with ozone can increase fish production by more than 30%, shrimp production by more than 60%, and the survival rate of fish, shrimp and crab fry by more than 90%. Ozone is used for aquaculture water. Generally, for viruses and bacteria that cause harm, ozone concentration of 0.5- 1.2mg/L can kill all bacteria in water, and 0.5-0.7mg/L can be used as a preventive measure. Ozone has been widely used in the treatment of aquaculture wastewater in Europe and America because of its remarkable economic benefits. In recent years, due to the rapid development of China's economy and the relative lag of environmental governance, environmental pollution has intensified and water pollution has become increasingly serious, and it is not uncommon for polluted water bodies to cause a large number of fish deaths. In the case of large investment and slow effect in environmental treatment, large-scale and large-scale promotion of ozone water treatment project in aquaculture can achieve double promotion of economic and social benefits.
In addition, the application technology of ozone technology products in circulating water, industrial wastewater and domestic sewage treatment is relatively mature, and the effect is remarkable. In the current situation of water shortage, it is of great significance to improve the utilization rate of water and save water.
Application in daily life
1. Ozone is one of the strongest oxidants known to be available. In practical use, ozone has outstanding sterilization, disinfection and degradation of pesticides, and it is an efficient broad-spectrum fungicide. Ozone can oxidize and denature the protein shell of bacteria such as bacteria and fungi, and can kill bacterial propagules, spores, viruses and fungi. Common Escherichia coli, Streptococcus faecalis, Staphylococcus aureus, etc. The killing rate is over 99%. Ozone can also kill Bacillus virus, cold virus and so on. Ozone diffuses rapidly and evenly in indoor air, and there is no dead angle in disinfection.
Second, ozone only kills viruses and bacteria, and is harmless to healthy cells, because healthy cells have a powerful balanced enzyme system.
Third, ozone can sterilize and purify the air, prevent cross-infection of diseases, and remove the odor of bedrooms, living rooms, kitchens and bathrooms. Ozone gas has the functions of sterilization, disinfection, mildew prevention and dust mites removal for indoor bedding, clothes, carpets, wardrobes, shoe cabinets and coins.
4. The short sunshine time, high humidity and serious air pollution in some areas of China can better reflect the special role of ozone.
The most suitable way for ozone is to dissolve ozone in water to form so-called "ozone water". Some developed countries in Europe and America call "ozone water" universal water. Its sterilization speed is more than 1000 times higher than chlorine.
6. Ozone water can disinfect and sterilize underwear, underpants, diapers and bags used by women and children.
Seven, ozone water can be used for fruits and vegetables, meat sterilization, preservation, odor removal. At the same time, it has the function of degrading phosphorus-containing pesticides remaining on the surfaces of fruits and vegetables, and can prolong the fresh-keeping period of food.
Eight, ozone water can clean the skin, maintain the skin, and reduce the irritation of cosmetics to the skin. Cold compress and soaking burns, cuts and lumps with ozone water can accelerate wound healing and prevent infection.
Nine, ozone products can be widely used in: families, hospitals, hotels, restaurants, beauty salons, public toilets, food processing industry, schools, kindergartens, nursing homes, finance, securities, offices, entertainment places, military, industry, agriculture, fisheries, aquaculture and other environmental protection fields.
X. the role of ozone therapy in human body
(1) Inactivate bacteria, viruses, etc. Ozone can destroy the integrity of cell membrane, thus entering cells, inactivating cells, and removing them from the body and replacing them with healthy cells.
(2) Promoting circulation For circulatory system diseases, ozone can reduce or eliminate the agglomeration of red blood cells in blood, restore their elasticity, make them pass through capillaries, and enhance the absorption of oxygen. At the same time, it can also increase arterial pressure, reduce blood viscosity and promote blood circulation. The oxidation of platelets by ozone can also remove waste and dredge blood vessels.
(3) Promoting oxygen metabolism Ozone can promote the glycolysis rate of red blood cells and promote the release of oxygen from human tissues. At the same time, it can also stimulate free radical scavengers and produce enzymes by some protective enzymes. Accelerate Krebs cycle and increase ATP production. NaOH can also increase the production of vasodilators.
(4) Formation of Peroxidase Ozone reacts with unsaturated fatty acids to generate hydrogen peroxide. Lipid peroxide products include alkoxy, peroxy, singlet oxygen, ozone oxide, carbide, alkane and dilute hydrocarbon.
(5) Ozone decomposing malignant tumor can inhibit the growth of malignant tumor. In addition, ozone can also oxidize the lipid layer of malignant cells, phagocytize cells to produce H2O2 and carboxyl groups, and kill bacteria and viruses. Its principle is that ozone converts L- arginine into ornithine. Nitrite and nitrate.
(6) Parallel ozone therapy is not medicine or magic, but an effective treatment to restore human health. What really works is the human immune system.
Ozone (chemical formula O3), also known as active oxygen, triplet oxygen, super oxygen and oxygen enrichment, widely exists in the ozone layer 20 kilometers away from the earth's surface. Because it can absorb most ultraviolet rays from solar radiation and protect life on earth from harm, it has attracted worldwide attention.
There is still a trace of ozone in the air (the content is 0.0 1 ~ 0.04 ppm), which is the highest in waterfalls, seaside and forest areas. The ozone concentration in general forest areas can reach 0.0 1~0.04ppm, which is produced by the way that ultraviolet rays of sunlight are condensed by water droplets and oxygen in water droplets reacts to become ozone. Especially when it thunders in rainy days, lightning will produce a lot of ozone. These trace ozone in the air effectively inhibited the abnormal reproduction of bacteria and molds in nature and maintained the ecological balance.
1785, when the Germans used the motor, they found that there was an odor when the motor was discharged. 1840, German scientist Schonbein identified this odor as O3 and named it ozone. Since then, European scientists have taken the lead in studying the characteristics and functions of ozone. After discovering the broad-spectrum bactericidal effect, they began to apply it to industrial production. Among them, a Swedish beef company used ozone to keep beef fresh, starting from 1870.
/kloc-in the 0/9th century, people realized the strong oxidation of ozone, and found that ozone had oxidation effects on wood, straw, starch, plant pigment, natural rubber, fat, animal and vegetable oil, alcohol and so on. 1868, Germany? Gebbers (Germany? Gebeth) obtained the first patent of ozone application technology, which used ozone to oxidize coal tar mixture into products suitable for coatings and paints. 1873, ozone was used in sugar production and flax bleaching in Europe. Over the past 100 years, the application of ozone has penetrated into many fields and made great contributions to the development of human production technology. The application of ozone can be divided into four areas according to its use: water quality treatment, chemical oxidation, food processing and preservation, and medical treatment. Application research and equipment development in various fields have reached a fairly high level. Independent ozone technology industries and departments have been formed in the world, and the International Ozone Association (IOA) established by 1973 is located in Canada. The Association holds an international conference every two years to exchange papers and reports on the development of ozone technology in various countries. In developed countries, IOA regional organizations are generally established for academic exchanges.
After World War II, the international ozone application technology has made great progress. First of all, in 1902, the first large-scale water plant using ozone to treat water quality was established in paderborn, Germany, which pioneered the treatment of ozone water. Now there are thousands of ozone water plants in the world. The application of ozone in waterworks in Europe, America, Japan, Canada and other countries has reached a universal level. Using ozone instead of chlorine to disinfect and purify tap water can be directly drunk. Almost all mineral water and pure water manufacturers are equipped with ozone equipment. In the early 1970s, the United States began to use ozone to treat domestic sewage, the main purpose of which was to sterilize, remove pollutants, decolorize and so on, so as to meet the discharge standards. In Japan, sewage is treated by ozone and used as reclaimed water in water-deficient areas. The United States, Japan, Germany, France and other countries have established large-scale ozone sewage treatment plants in recent years. Secondly, the industrial application of ozone has also been very common, mainly used in chemical, petroleum, paper, textile, pharmaceutical and perfume industries. The application of food industry is more popular. 1904, Europe used ozone to preserve milk, meat products, cheese, protein and other foods. In the late 1930s, 80% of oocyte cryopreservation warehouses in the United States were equipped with ozone generators. After World War II, Europe, the United States and Japan used ozone in the storage, manufacture and transportation of food, fruits and vegetables. In medical treatment, Japan used ozone for physical therapy during World War II, while Russia used strong air (ozonated air) to strengthen athletes' physique. At present, there are many medical uses in the world, such as air disinfection in wards and operating rooms, ozone water disinfection of medical instruments, ozone treatment of dental diseases (oral surgery and maintaining oral sterility), ozone combined with radiotherapy treatment of cancer, drinking ozone water treatment of gynecological diseases, ozone gas injection treatment of fistula and hemorrhoids, varicose veins and so on. In terms of health care, it is popular in Japan and Taiwan Province Province to inhale strong air (air with low ozone concentration) to strengthen the body, and to spray ozone water to sterilize and beautify the body. The popular high-tech beauty is actually the application of ozone beauty. In major international competitions, swimming pools and diving pool also use ozone sterilization to protect the health of athletes.
Scientific research has found that ozone molecules are extremely unstable, which can decompose to produce monoatomic oxygen (O) and hydroxyl (OH) with strong oxidizing ability, quickly destroy the internal structure of bacteria, viruses and other microorganisms, and have a strong killing effect on various pathogenic microorganisms! The sterilization effect of ozone is much better than that of chlorine, the sterilization speed is 200 ~ 3000 times faster than that of chlorine, and it can be decomposed into oxygen by itself, leaving no harmful substances and causing no secondary pollution.
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