Ozone has been proven to be a strong oxidant in water treatment processes, except for fluorine. It can first decompose organic compounds at a reaction rate hundreds of times higher than chlorine, preventing chlorine from combining with urea to form chloramines. It can also oxidize the precursor of THM, greatly reducing THM. ...

Ozone has been proven to be a substance other than fluorine in water treatment processessuperA strong oxidant that can first decompose organic compounds at a reaction rate hundreds of times higher than chlorine, preventing chlorine from combining with urea to form chloramines. It can also oxidize the precursor of THM, greatly reducing THM. In addition, the hydroxyl groups formed in water after ozone decomposition can hydrolyze multivalent metal ions into colloidal compounds, which are filtered out through a sand filter. This not only improves the sensory perception of water, but also oxidizes and decomposes organic matter in the water, which is then filtered out. Therefore, even to prevent cross infection, residual chlorine of about 0.5mg/L needs to be maintained in the swimming pool, and the dosage of chlorine agent is greatly reduced, generally only 15-20% of that used alone. Experience has shown that when the residual ozone in the pool water is below 0.15mg/L, it does not cause any adverse effects, and even long-term swimming does not pose health hazards. Western industrialized countries, especially in Europe, have widely accepted this fact and used ozone in about 30000 swimming pools, further developing traditional German standards and achieving the elimination of chlorine based sterilization technology. This technology has been mainly promoted and applied in France and some non German speaking countries for more than 30 years, accumulating a wealth of beneficial experience and providing systematic and practical experience for the development of ozone treatment pool water technology. In recent years, countries in the Americas, including the United States, have noticed this situation and begun to extensively adopt ozone technology. The development of swimming in China started relatively late, and the construction scale of swimming pools is relatively small, with limited application of ozone technology. Recently, with the opening up to the outside world, some swimming pools that hold official or competitive events have been equipped with ozone treatment devices in accordance with national regulations or standards. In addition, some public swimming pools, hotels, and residential swimming pools have also requested the use of ozone technology.

Swimming Pool Ozone Generator

IISwimming Pool Ozone GeneratorDesign of Swimming Pool Water Ozone Disinfection System

CT value is the main design parameter of ozone disinfection system:

Where C represents ozone concentration, measured in mg/L; T represents contact time, measured in minutes; The product CT value of the two indicates the effectiveness of the disinfection process. For example, when the ozone concentration is 0.4mg/L and the contact time is 4 minutes, the CT value is equal to 1.6. Swimming pool water is different from drinking water: (1) Swimming pool water is in a closed cycle, with a daily number of cyclesno less than4 times, and the drinking water is straight through. (2) As the number of swimmers increases, the required amount of oxidants in the pool water also increases. (3) The temperature of swimming pool water is generally between 25 ℃ and 40 ℃, while the temperature of drinking water is generally between 0.5 ℃ and 25 ℃. (4) Swimming pool water also needs to be treated with chlorine as an auxiliary disinfectant. (5) The circulating water in the swimming pool is filtered and disinfected with ozone. Therefore, using a CT value of 1.6 to determine the size of the swimming pool water ozone disinfection system is relatively safe. In some areas, a low CT value of 0.8 is used, with an ozone concentration of 0.2mg/L-0.25mg/L and a contact time of 3.5m-4min. At this time, the amount of chlorine added as an auxiliary disinfection can be reduced by 65%. When chlorine is used as the main disinfectant and ozone is used as the finishing disinfectant, the CT value can be less than 0.8, the ozone concentration is less than 0.5mg/L, and the contact time is less than 1 minute.

■Swimming Pool OzoneInvestment method:

The standard requires negative pressure injection, usually using jet or gas-liquid mixing pump suction method. Practice has shown that the mixing efficiency of gas-liquid mixing pump can reach about 80%, and the efficiency is even higher when adding ozone mixing tank.

Jet bypass injection method: Ozone is usually introduced into the water using a jet injector installed on the side flow pipe. In order to ensure the inlet pressure of the jet injector, a pipeline pump is installed on the side flow pipe for pressurization. The mixture of water and ozone after the jet generator enters the reaction tank from the upper side and comes into full contact, and then flows out from the lower side to connect with the main circulating water pipe of the swimming pool. The water in the bypass pipe is disinfected under high ozone concentration and then mixed with the water in the main pipe to produce oxidation reaction. The water circulation cycle of commercial swimming pools is 6 hours, and the water flow rate of the bypass pipe is 15% to 25% of the main flow rate of the circulating water, which can ensure sufficient mass transfer efficiency and sufficient contact time for ozone before entering the main pipeline.

Gas liquid mixing pump addition method: This pump has one ozone gas inlet, one water inlet, and one water outlet. Connect the branch pool water directly to the inlet of the pump. If this method can be combined with an ozone mixing tank, the efficiency can reach over 90%.

Method of adding ozone generator to swimming pool

■ Water treatment cycle mode, cycle period, and flow rate

There are three circulation methods for pool water purification treatment: forward flow, reverse flow, and mixed flow. Standardized pools and competition pools should adopt the mixed flow purification treatment circulation method.

Cycle cycle: Tx=24/n (h), where n is the number of cycles per day. Public swimming pools typically have 4-6 cycles.

Circulating flow rate: qx=α f • V/Tx, where Tx cycle period, α f is the water volume coefficient of the pipeline, water purification equipment, and supply water tank, generally selected according to 1.1-1.2, and V is the water volume of the swimming pool.

Determination of Ozone Dosage for Swimming Pool:

ozone generatorProduction rate (g/h)=qx × c=α f • V/Tx=circulating water flow rate (m3/h) × ozone concentration (g/m3). The reaction tank is used to oxidize inorganic and organic pollutants in water by dissolved ozone and carry out disinfection and sterilization. The exhaust valve on the upper part of the reaction tank should be connected to the ozone exhaust gas destruction device to remove undissolved ozone before entering the atmosphere.

Taking a standard swimming pool (21m * 50m, water depth 1.8m) as an example: the standard pool has a water volume of 1890m3

Adopting split traffic injection

Ozone dosage: 0.6-1.0mg/L, taking a standard swimming pool as an example, qx=1.1 • 1890/6=340 tons/hour

Single ozone dosage: Q=qx • dosage, dosage 0.8mg/l, then Q=qx × c=α f • V/Tx × c=1.1V/6 * 0.8=272 grams/hour.

■Swimming Pool Ozone GeneratorDetermination of the volume of the ozone reaction tank:

Ozone reaction tank volume (m3)=circulating water flow rate (m3/h) × bypass water percentage (%) × reaction time (h).

Within the temperature range of swimming pool water, the saturated concentration dissolved in the pool water follows Henry's law. The higher the concentration of ozone in the gas produced by the ozone generator, the higher the saturated concentration in the water, and the higher the mass transfer equilibrium concentration of dissolved ozone, resulting in better disinfection performance. When choosing an ozone generator, this should be taken into consideration.

IIISwimming Pool Ozone GeneratorAdvantages in swimming pool water treatment

Since the discovery of ozone by SCHOEMBEIM in 1840, its application has a considerable history. Ozone, as a strong oxidant and broad-spectrum fungicide second only to fluorine, has been widely used in water treatment and disinfection systems for swimming pools. With the increasing awareness of environmental protection and health, the improvement of production processes, and the reduction of production costs, swimming pools using ozone disinfection are gradually replacing those using chlorine disinfection and are being accepted by people. Currently, all public swimming pools in Europe and North America use ozone disinfection, with over 500000 in the United States and widespread use in Europe. Hong Kong, China, converted all public swimming pools to ozone disinfection in 1997. In China, since the Kangle Palace at the 1990 Asian Games, numerous large public swimming pools, water parks, fitness and leisure clubs have adopted ozone disinfection in their swimming pools and spas,Ozone disinfectionSwimming pools are moving from aristocratic to popular.

■superStrong fungicide.

ozoneIt is a very active and highly oxidizing agent known to be available in natureveryOne of the strong oxidants, it mainly relies on its powerful oxidizing effect to kill bacteria. Ozone and its secondary products (such as hydroxyl groups) haveveryStrong bactericidal and virus killing properties make it a highly effective broad-spectrum fungicide. It can oxidize and decompose glucose oxidase and dehydrogenase oxidase in bacteria, and can also directly interact with bacteria, causing the redox process of bacterial substance metabolism to be disrupted, thereby disrupting the growth and reproduction process of bacteria and causing bacterial death. Its bactericidal effect is rapid and can effectively kill bacteria, viruses, spores, and insect eggs in water within a few seconds, effectively preventing the spread of infectious diseases. Experimental results have shown that ozone of the same concentration is 600-3000 times more effective in killing bacteria and viruses than chlorine. At an ozone concentration of 1mg/l, the inactivation of fecal Escherichia coli only takes 5 seconds, while achieving the same effect with the same concentration of chlorine takes 15000 seconds. The rapid killing of spores and F bacteriophages with strong chlorine resistance is particularly important, and viruses such as ADIS and red eye virus that are powerless against chlorine can be effectively killed.

Environmentally friendly green bactericides.

Ozone is an environmentally friendly and green disinfectant. The process of ozone disinfection of circulating water in swimming pools is an oxidation process, and the product is dissolved oxygen. It does not increase the harmful substances and salt content in the water and does not cause any secondary pollution to the environment. The traditional chlorine disinfection method for swimming pools requires the addition of a large amount of chlorine containing disinfectants to achieve the goal of sterilization. Chlorine preparations react with organic matter in the water to produce various chlorinated organic compounds, all of which are carcinogenic and mutagenic substances.

Enhance health and comfort.

The swimming pool is disinfected with chlorine, and over time, chlorinated organic compounds andharmGas, which accumulates above the swimming pool and is difficult to dissipate, damages the respiratory organs of people. People who are in the midst of it will smell a pungent chlorine smell and feel discomfort in their chest and lungs; At the same time, these toxic substances are absorbed by the human body (the human body can absorb 500 milliliters of water per hour in water), which can cause eye irritation and redness during swimming; People who swim for a long time may notice that their hair turns yellow and brittle, and their skin gradually becomes rough, which seriously affects their physical health. Ozone disinfection is used in swimming pool water treatment to eliminate the formation of chlorinated ammonia compounds, which can fundamentally prevent the production of carcinogenic halogenated organic compounds such as trihalomethanes (THMS). It is these chloramine compounds that can irritate the skin, eyes, and respiratory tract of swimmers and athletes, causing red eyes and skin irritation during swimming. They also have a bleaching effect on hair. Swimming pools disinfected with ozone will not cause such problems, and people who exercise swimming can feel comfortable and worry free. During the processing, the residual ozone in the water returning to the swimming pool will not exceed the safe limit, and it can also sterilize and purify the air, making indoor air clean and comfortable.

Degradation and removal of pollutants from water.

According to relevant information from the Beijing Health and Epidemic Prevention Station, the organic matter, especially ammonia nitrogen (urea), in chlorine disinfected swimming pools exceeds the normal standard by several times, and the water is prone to deterioration. The reason for this is that filtration cannot remove soluble organic matter, and chlorine cannot decompose organic matter such as ammonia nitrogen. In the ozone disinfection system, due to the strong oxidizing properties of ozone, it can react with organic matter in water, effectively decompose humus in water, decompose small organisms that scatter light in water, prevent the accumulation of organic pollutants, improve water quality, decolorize, and oxidize iron and manganese ions in water, thereby degrading pollutants and achieving the effect of purifying water quality. This greatly improves the sensory and clarity of water, making the pool water appear beautiful light blue. The water quality meets the water quality standards of FINA and the World Health Organization. However, chlorine preparations do not have this effect.

Greatly reduce medication consumption.

When using chlorine disinfection, the addition of chlorine agents will inevitably cause a change in the pH value of water, making people feel uncomfortable. Therefore, a large amount of alkaline or acidic agents need to be added to neutralize it. When the temperature is high and the passenger flow is large, the water quality is often poor. At this time, chlorine preparations need to be added in large quantities, and ozone is a neutral substance that does not cause such problems. Ozone can ensure the stability of water quality during high passenger flow and hot seasons. However, due to the short half-life of ozone, it cannot remain in water for a long time and still requires the addition of a small amount of chlorine containing disinfectant as an auxiliary long-acting disinfectant. However, the amount of chlorine added can be reduced by more than 65%. Meanwhile, ozone has a micro flocculation effect, so under normal passenger flow, coagulants can be avoided. Under certain usage conditions, such as countercurrent circulation, no use of activated carbon filter tanks, and even no need to add chlorine agents, flocculants, or pH regulators, it can be useddirectUse ozone as a water treatment agent.

Reduce corrosion of facilities.

The use of chlorine to produce hypochlorous acid and its derivatives severely corrodes the equipment and structures in the swimming pool, such as the grid and heating system. After using ozone disinfection, the amount of chlorine disinfectant used is greatly reduced.

Better water quality.

The ozone disinfection system is also equipped with activated carbon adsorption filters to remove residual ozone, organic pollutants, etc. in the circulating water of the swimming pool, ensuring bothOzone disinfectionThe safety of the system has also undergone advanced treatment on the circulating water, and its water quality will be better than ordinary tap water.

■ More convenient and safe to use.

The raw materials for the production of ozone are inexhaustible oxygen in the air, so there is no need to consider handling or storage during the production process. The operation and use of ozone generators are very simple, with high safety, and daily management and maintenance work are also relatively simple. Chlorine preparations pose certain risks during transportation, storage, and use.

4、 Characteristics of using ozone generators in the swimming pool industry

Quick response and low dosage: Ozone can quickly kill bacteria, spores, and viruses that diffuse in water and has bactericidal and inactivating effects at very low concentrations.

Strong adaptability: Within the range of pH 5.6-9.8 and water temperature 0-37 ℃, it has little impact on the disinfection performance of ozone.

The half-life of ozone is very short, it can decompose into oxygen in 20 minutes and does not produce secondary pollution in water

Can destroy organic matter in water, improve the physical properties and organ sensation of water, perform decolorization and deodorization effects, make water appear blue without changing the natural properties of water. Ozone has a disinfectant effect on water