Laboratory pure water system is not as simple as you think

      The pure water produced by the laboratory pure water system is of high purity, which completely removes the conductive medium in the water, and at the same time removes the non-dissociated gas, colloid and organic matter (including bacteria) to a very low level of water. Ultrapure water is a kind of water with very high purity, which means that the conductive medium in the water is almost completely removed, and the non-dissociated gas, colloid and organic matter (including bacteria) are also removed to a very low degree. Its conductivity is generally 0.1~0.055uS/cm, resistivity (25C)>10x1060/cr salt content <0.1mg/L. The ideal pure water (theoretically) is 0.055uS/Cm, and the resistivity (25°C) is 18.3x106Q/cm.

The laboratory pure water produced by the laboratory pure water system can be divided into the following categories:

1. The physical purity of grade III pure water is generally less than 50 uS/cm, single-distilled water, double-distilled water, ordinary deionized water and reverse osmosis water all belong to this level. It is generally prepared by purifying tap water. The main purpose of grade III pure water is to clean bottles and dishes, use water for high-pressure disinfection devices, and feed water into ultrapure water meters in artificial environment rooms.

2. Grade II pure water is a vague range, commonly expressed as 5-15M-cm. However, &uml; grade pure water is not strictly limited to this range, and the range of 1-17M-cm can be regarded as grade II pure water. Grade II pure water is generally made by ion exchange or electrodialysis of Grade III pure water. It is mainly used for the preparation of general reagents, water for general chemical experiments and water supply for ultrapure water instruments.

3. Grade I ultrapure water refers to water with a physical purity greater than 18M-cm. It is customary to say that the resistivity of 18.2M-cm is the index of Grade I ultrapure water. The grade of ultrapure water must be purified from grade III or grade Il pure water through nuclear grade ion exchange resin. It is mainly used for high-precision analytical experiments and life science experiments that require high water purity.

The working principle of the laboratory pure water system:

Using the combination of advanced reverse osmosis technology and ion exchange technology, using microcomputer single-board computer program control, water quality detection automatic display, so as to obtain high-quality produced water, its water resistivity can generally reach 18Ma/cm , The booster pump, electromagnetic moisturizing, high-capacity ion exchange resin, R.O reverse osmosis membrane, filter element, pipeline connection, control and control originals, and ultraviolet lamps used in the equipment are all imported products.

The reverse osmosis principle of the ultra-pure water machine is to apply a pressure greater than the natural osmotic pressure on the raw water side, so that the water molecules penetrate from the side with high concentration to the side with low concentration. Because the pore size of the reverse osmosis membrane is much smaller than hundreds of times or even more than the dry times of viruses and bacteria, various diseases, bacteria, heavy metals, solid solubles, polluted organics, calcium, calcium and magnesium ions cannot pass through the reverse osmosis membrane at all. , so as to achieve the purpose of water purification.