Swimming pool water treatment is divided into two parts: physical process and chemical process, both of which are indispensable in swimming pool water treatment. The physical process is that swimming pool water is filtered and purified by circulating water treatment equipment. Chemical process refers to adding chemical agents to disinfect, flocculate and remove algae while circulating the pool water, and then making the pool water clean and hygienic through physical process. Therefore, only when these two processes are carried out at the same time can the water quality of the swimming pool meet the national standards and your swimming pool successfully pass the inspection by the health and epidemic prevention department. The most important thing is that people who exercise in the swimming pool can really achieve the purpose of fitness and will not be infected with diseases. What we discuss below is the chemical treatment of swimming pool water.
First, the swimming pool water disinfection
Disinfection of swimming pool water is a very important issue. If it is not solved properly, the swimming pool may become a place to spread diseases. The swimming pool is suitable for the growth of pathogenic bacteria such as typhoid fever, paratyphoid fever, dysentery, hepatitis, acute conjunctivitis and pustulosis. Hepatitis virus and encephalitis virus often transmit diseases through water. The disinfection of swimming pool water shall generally meet the following requirements:
1. The disinfection method adopted must have a strong sterilization effect, which can quickly and massively kill bacteria, that is, 99.9% of microorganisms can be killed within 30 seconds;
2, the sterilization effect should have a reasonable duration, which can effectively control the new pollution caused by swimmers entering the pool;
3. For the swimmer's mucosa, the skin must be non-irritating and there will be no unpleasant smell in the air;
4. The dosage must be easy to control, and the amount and effect of chemicals in water can be quickly determined by simple methods;
5. Considering all relevant factors, the capital investment and transportation cost must be reasonable.
It is difficult to find an absolutely ideal disinfection method for pool water. At present, chlorine disinfection is the most commonly used method. Chlorine can produce hypochlorous acid in water, which will spread to the surface of bacteria, cross the cell membrane and enter the interior of cells. In bacteria, the oxidation of chlorine atoms will destroy an enzyme system in bacteria and eventually lead to the death of bacteria.
An important feature of chlorine disinfection is that it can keep a proper amount of residual chlorine in the disinfected pool water as needed, so that the pool water that is constantly polluted by human body can be continuously disinfected during the use of the pool water. Generally, the residual chlorine content in swimming pool water is required to be 0.4-0.6 mg/ 1. In addition, in order to ensure the efficacy of disinfectant and not cause corrosion of equipment and swimming pool surface, the relative pH value of swimming pool water is required to be kept at 7.4-7.6. Liquid chlorine and hypochlorite are commonly used in traditional chlorine disinfection methods. Liquid chlorine has the advantages of simplicity and low cost, and can kill many bacteria, pathogenic bacteria, viruses and parasitic eggs. It plays a key role in preventing the epidemic of cholera and typhoid fever, but it is easy to leak out. Safety must be paid attention to when storing and using. Sodium hypochlorite solution is a powerful disinfectant, efficient oxidant and excellent bleaching agent commonly used in China at present, which has been widely used in all walks of life in China. Compared with other existing disinfectants, sodium hypochlorite has a broad-spectrum, efficient and rapid disinfection effect, and is safe, non-toxic and has no toxic and side effects on human body, so it is widely used. It is an ideal, convenient, safe, convenient and efficient disinfection products among chlorine-containing disinfectants in China. Its available chlorine content is 12.5%- 13.5%, and it is extremely unstable, easy to decompose and not durable. The evaluation of disinfectant should comprehensively consider its killing ability and stability in water. For the four disinfectants commonly used in water treatment, that is, liquid chlorine, chlorine dioxide, sodium hypochlorite, chloramine and ozone, from the perspective of bactericidal ability, ozone > chlorine dioxide > sodium hypochlorite > liquid chlorine > chloramine; In terms of stability, chloramine > sodium hypochlorite > chlorine dioxide > liquid chlorine > ozone. It can be seen that sodium hypochlorite is an excellent and stable disinfectant, which can be used not only for disinfection of various water bodies, but also for other sanitary disinfection. time
Performance comparison between sodium chlorate generator and several disinfectants;
1, sodium hypochlorite has high solubility in water, and it volatilizes little from water during disinfection, and almost no smell can be heard. However, when liquid chlorine is used for disinfection, due to improper operation, some chlorine gas escapes from the water with strong smell, which requires a certain period of time to stop the pool for ventilation, while sodium hypochlorite disinfection does not need to stop the pool, thus prolonging the pool opening time, allowing disinfection while swimming, with great flexibility, good randomness and less constraints.
2. Liquid chlorine is difficult to transport and store, and it is highly toxic, which is very harmful to people and animals, especially those who operate for a long time, and are prone to bronchitis and bronchitis.
3. Sodium hypochlorite has obvious oxidation, decoloration, deodorization and deodorization effects, which can obviously change the color and smell of water and does not react with ammonia nitrogen and nitrogen-containing organic matter. Sodium hypochlorite is a strong oxidant, which will not react with organic substances in water to generate organic chlorides such as chloramine, chlorophenol and chloroform. It has a strong oxidative degradation effect on carcinogens and organic poisons in water.
4. Sodium hypochlorite has wide bactericidal spectrum, high efficiency and strong killing ability to viruses and spores. Small dosage, short action time and good effect. Practice has proved that sodium hypochlorite is very suitable for disinfection of swimming pool water, killing all kinds of viruses, bacteria and microorganisms spread in water supply.
5. Sodium hypochlorite has the ability to kill and inhibit the growth of algae in water. After adding sodium hypochlorite, the propagated algae can be killed in a short time.
6. The sodium hypochlorite generator produces liquid, which has good stability, safety, no hidden danger, convenient dosing and easy realization of quantitative dosing. However, the chlorine dioxide generator has poor stability and the dosage is difficult to control because it produces gas; If there is a problem in the process of administration, there is still the danger of explosion.
7. All technical indicators of sodium hypochlorite generator have national standards, while chlorine dioxide generator is a nonstandard product, so users can't check the quality of purchased equipment.
8. Chlorine dioxide generator is a comprehensive disinfection gas produced by electrolysis of saturated salt solution. The experiment shows that the chlorine dioxide gas content is low, accounting for only 8- 10%. In addition, the chlorine dioxide generator adopts diaphragm electrolysis, and the filter diaphragm is a permeable membrane, which is easy to block and needs to be replaced frequently. In the process of electrolysis, it is necessary to manually discharge alkali and dilute electrolyte. Sodium hypochlorite generator is diaphragm-free electrolysis, which does not need to change membrane, discharge alkali and dilute electrolyte, so the labor intensity of workers is not great. 9. Taking water as the transport carrier and adding chlorine dioxide to the water to be disinfected is undoubtedly a great waste of water resources. Sodium hypochlorite can be added directly without water as a carrier.
10, the water treatment cost per ton of sodium hypochlorite is about 0.02 yuan, while the water treatment cost per ton of chlorine dioxide is about 0.05 yuan.
In a word, for the disinfection of swimming pool water, sodium hypochlorite disinfection method is efficient, low consumption, safe and reliable, and it is an ideal choice for disinfection products.
Coagulation treatment of swimming pool water
The Water Quality Standard for Swimming Pools stipulates that the turbidity of swimming pool water shall not exceed 5 degrees. The swimming pool water is turbid due to sediment, clay, algae, microorganisms and some organic substances. In order to reduce the turbidity of swimming pool water, coagulation treatment is needed, that is, coagulant is added to the water to absorb the small particles of turbidity in the water, so that they condense into large particles, and finally precipitate is produced and discharged out of the pool through a filter.
Our company specially prepared "high-efficiency water purifier A and B solutions" and "new high-efficiency flocculant" for swimming pools, which have strong coagulation effect and can purify the pool water after repeated circulating filtration.
Three, swimming pool water algae removal treatment
The water temperature of swimming pool is generally between 20℃ and 30℃, which is very suitable for algae reproduction and growth, such as irregular algae removal treatment. The pool water will turn dark green, which will seriously increase the turbidity of the pool water and make the bottom of the pool black and smelly. In this case, the treatment should be carried out through the following steps: first, adding disinfectant, second, adding algaecide, third, adding flocculant, and fourth, strengthening circulation.
Fourth, the water treatment process
Swimming pool water is easy to treat, and the water treatment of swimming pool is divided into two parts, circulating water treatment of swimming pool and overflow reuse water treatment. Based on the treatment process of swimming pool water at home and abroad, the following processes are generally adopted. The circulating water of the original swimming pool is directly filtered and then treated with disinfectant. The disinfectant is sodium hypochlorite disinfectant, which is prepared and provided by the sodium hypochlorite generator on site. However, as long as there are no defects in the design of the circulating pipeline, the overflow water in the swimming pool avoids the waste of water resources caused by system defects, so there is only overflow water within the normal range. For normal swimming pool overflow water, if it is to be treated, it should be coagulated first, then filtered, circulated by the swimming pool pump, disinfected with drugs, and finally entered the swimming pool. Quartz sand is generally used as the filter material of the main circulating filter, which has long service life and good filtration effect.
Remarks:
1, the dotted line part is generally not done, unless the design of the swimming pool is defective, resulting in a large amount of overflow.
2. The type and quantity of filters can be selected according to the amount of water in the swimming pool.
Legal basis:
Article 4 The site selection, design and final acceptance of the Hygienic Code for Swimming Places issued by the Ministry of Health.
(a) natural swimming places should be located in the upstream of pollution sources. There shall be no sewage outlets in the upstream 1000m and downstream1000 m, and there shall be no pollutant accumulation and permeable pollution sources in the coastal1000 m. The geology of the bottom bank is suitable, and there should be no obstacles and pollutants such as branches, stumps and reefs. The velocity of water flow is not more than 0.5 m/s, and a health protection zone should be designated. It is forbidden to open natural swimming places in schistosomiasis endemic areas or areas where snails are lurking.
(2) The site selection and design of newly built, rebuilt or expanded swimming places shall be entrusted to a qualified health technical service institution for hygienic evaluation at the feasibility demonstration stage or design stage and before the completion acceptance. The swimming place shall submit the design description, design parameters of water quality treatment, general layout of the place, raw materials for decoration, circulating purification and disinfection device of pool water and its working rules, design and installation of air conditioning and ventilation system and other relevant materials. Article 5 The internal and external environments of swimming places shall be kept clean, sanitary, comfortable, bright and ventilated, and the air quality shall meet the relevant national hygiene standards.