purified water(chun jing shui )

Purified water method:

Purified water production steps:

In the manufacturing process of purified water, not only the necessary filtration and softening processes of mineral water are used, but also the R.O. membrane with pore diameter of 1 / 10000 m (equivalent to 1 / 6000 of Escherichia coli and 1 / 3000 of virus) is used to remove all the impurities in the water, such as industrial pollution, heavy metals, bacteria and viruses in modern society, so as to obtain pure and sweet space water. This kind of reverse osmosis membrane made of high polymer materials can intercept all impurities except water molecules under high pressure, but at the same time, it can make use of dissolved oxygen and other gases in water which are beneficial to human health through the membrane. The oxidizing substances in water meet the requirements of American pure water for medical use. It is pure, non-toxic and sterile. It is a kind of oxygen-containing active water that can be directly imported.

purified water

This entry is compiled and applied by "popular science China" Science Encyclopedia

to examine

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Purified water refers to the water without impurities, which is called purified water or pure water for short. It is pure and clean water without impurities or bacteria, such as organic pollutants, inorganic salts, any additives and all kinds of impurities. The raw water is the water that meets the sanitary standards of drinking water. It is made by electrodialyzer method, ion exchanger method, reverse osmosis method, distillation method and other appropriate processing methods. It is sealed in the container and does not contain any additives. It is colorless and transparent and can be drunk directly.

The space water and distilled water on the market are pure water.

brief introduction

The so-called purified water is the natural water through multiple processes of treatment, purification and purification of water. After a number of processes, the purified water can remove harmful substances and bacteria, so it can be drunk directly.

Water is necessary to maintain life. Some health experts recommend at least eight cups, but there is no specific regulation. The demand for water varies from person to person, depending on the subject's condition, proper physical exercise, and the temperature and humidity of the environment. The sources of daily water include drinking water, drinks, water and water in food. Drinking water intake of mineral nutrients is not clear. Generally speaking, inorganic minerals enter surface water and groundwater through rainwater runoff or through the earth's crust, making the water include calcium, zinc, manganese, phosphorus, fluorine and sodium compounds. The nutrients produced from water provide an important part of the daily water demand of some arthropods and desert animals, but only provide a small part of the necessary intake of people, so there is no scientific basis for drinking pure water for a long time. But drinking too much water can also lead to water poisoning (hyponatremia)

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Coverage

Purified water, referred to as purified water or pure water, is pure and clean water (H2O), which does not contain impurities or bacteria, such as organic pollutants, inorganic salts, any additives and all kinds of impurities. The raw water is water that meets the sanitary standards of drinking water. The space water and distilled water on the market are pure water.

In China's bottled drinking water market, there are mainly pure water, mineral water, spring water and natural water, mineral water, etc. due to the resource constraints of mineral water, spring water, etc., and pure water is produced by using the water from the urban water supply system that meets the national drinking water standard through a certain production process, so it effectively avoids the invasion of various bacteria into the human body, and can effectively and safely supply water to the consumers The human body replenishes water and has strong solubility, so it has strong affinity with human cells and promotes metabolism.

major function

The reverse osmosis membrane, which filters the purified water, can remove the bacterial impurities in the water, replenish the body with the necessary water, and help excrete the toxins in the human body in a short time.

Drinking water is mainly to supplement water, not to supplement trace elements. Minerals and trace elements absorbed by human body mainly come from vegetables, fruits, rice, meat, etc., rather than from drinking water.

Diet is the main way for human body to take in nutrients, and the effect of water is very small. Zhong Kai, deputy director of Kexin food and nutrition information exchange center, said, "nutrients are not lost when water is washed. People are not sieves. It's not that simple." The loss of nutrition is related to natural conditions, age, amount of exercise and physique. Drinking water is not the decisive factor.

Water containing too much minerals in the body will cause unnecessary burden to the human body, and some minerals may not be absorbed by the human body. If it accumulates in the body for a long time, it will directly affect human health.

Drinking standard

In April 1998, the State Bureau of quality and Technical Supervision issued GB 17323-1998 "bottled drinking purified water" and GB 17324-1998 "Hygienic standard for bottled drinking purified water". In these two standards, there are 4 sensory indexes, 4 physical and chemical indexes and 11 health indexes.

Sensory index

Sensory indicators include chroma, turbidity, odor and visible matter. These indicators are the most basic indicators in the quality control of purified water, and the standard values formulated refer to the standards of drinking water (i.e. tap water). Most manufacturers produce purified water from tap water, which also goes through the process of coarse filtration, fine filtration and deionization purification. Therefore, the general purified water can reach the values required by the national standards.

Physical and chemical index

The more important physical and chemical indexes are conductivity and potassium permanganate consumption. Conductivity is the characteristic index of purified water, which reflects the purity of purified water and the control of production process. Because drinking water does not go through the process of deionization and purification, this index is not investigated. For purified water, "pure" is the most basic requirement, too high metal elements and microorganisms will lead to high conductivity. Therefore, the smaller the conductivity, the purer the water.

Potassium permanganate consumption refers to the milligram of oxygen consumed when the reducing substance in 1L water is oxidized by potassium permanganate under certain conditions. It mainly studies the content of organic matter, especially chloride in water. According to GB 17323-1998 "bottled purified drinking water", the consumption of potassium permanganate in purified drinking water (calculated by O2) shall not exceed 1.0mg/l. If the consumption of potassium permanganate is high, there may be microorganisms in the water exceeding the standard, or some manufacturers may increase the amount of disinfectant ClO2 in order to prevent microorganisms from exceeding the standard, resulting in some new organic halogenates. In this case, the free chlorine will also exceed the standard.

The content of nitrite is another important index in the national standard. Nitrite mainly comes from the nitrate in the soil near the water source, and the nitrate content is higher in the saline alkali soil, the soil with a large amount of nitrate fertilizer and the soil with molybdenum deficiency. According to the national standard, nitrite should not exceed 0.002mg/l.

Microbiological index

Microbiological indicators in the national standard of the total number of colonies, coliform, pathogenic bacteria and mold, yeast 4. From the situation of the detection of purified water in recent years, the microbial index is one of the indicators that are easy to exceed the standard. This is because microbial pollution is reflected in the production, processing, transportation and marketing of purified water. In the production and processing, workers do not pay attention to personal hygiene, and the cleaning and disinfection of recycled bottles are not strict. Some manufacturers even reuse recycled bottle caps in order to reduce costs. Due to the deformation of recycled bottle caps, the bottle mouth is not sealed, which may cause microbial pollution. The over standard of microorganism reflects the pollution degree of effluent. Among them, Escherichia coli reaches a certain index, which will cause human diarrhea. Pathogenic bacteria include Salmonella, Shigella, Staphylococcus aureus and Streptococcus B. The water polluted by Salmonella and Shigella can cause acute intestinal infectious diseases, diarrhea, fever and other symptoms; the enterotoxin produced by Staphylococcus aureus can cause human poisoning, acute gastrointestinal symptoms, and even life-threatening; Streptococcus B is the main pathogen causing human suppurative inflammation; mold and yeast are widely distributed in nature and grow in food In the process of reproduction, fungi absorb the nutrients of food, reduce the nutritional value of food, and emit peculiar smell, affecting the sensory of food, especially the toxins produced in the process of mold growth can cause chronic poisoning of human body, and even lead to cancer.

Metal index

The contents of lead, arsenic and copper are specified in the standard for metal elements. The requirements for lead and arsenic should not exceed 0.1mg/l, which mainly come from the environment affected by human activities, including the pollution of soil and rivers. Lead and arsenic are toxic and harmful elements. Lead can enter human body from respiratory tract or digestive tract and accumulate in human body. When the lead content in blood is 0.6-0.8mg/l, it will damage internal organs. Arsenic compounds will cause poisoning. Therefore, their content should be as small as possible. Copper should not exceed 1.0mg/l in the standard. Although copper is not a harmful element, it is not a good thing Quality, for purified water, is one of the signs to measure its purity.

Organic index

The content of chloroform and carbon tetrachloride are the main indicators of organic matter in the national standard. Because the quality problem of barreled purified water mainly focuses on the microbial detection exceeding the standard, in order to solve this problem, many manufacturers do not start from the production process and quality management, but only try to solve the problem of microbial pollution of purified water. Most commonly used disinfectants are chlorine containing disinfectants, such as chlorine dioxide. Bottled purified water can produce a kind of water because of chlorination

Chinese PinYin : Chun Jing Shui