In-depth understanding of the laboratory must be indispensable for ultra-pure water machine

With the advancement of science and technology, people's understanding of various things in the natural world is moving toward microscopic and essential directions. Many experiments, testing requirements for reagents or impurities in the culture environment have reached the ppb level. Even reaching the ppt level; as in the life science research process, it is very sensitive to many pollutants in the water, especially heavy metals and soluble organic matter.

The main purpose of pure water:

● Final cleaning of laboratory utensils

● Buffer, chemical reagent preparation water

●Microbial culture medium preparation water

●Hydrogen generator, indoor humidifier, pure water for autoclave

● drinking water for human or experimental animals;

The main use of ultrapure water:

●Water for plant and plant cell culture

●All kinds of medical biochemical analyzers, analyzers, hemodialysis instruments

● Analytical reagents and drug configuration dilution water

● * Rational, pathological, toxicological experimental water

● purified water and high purity water for hospitals, pharmaceutical preparation rooms and central laboratories

●Atomic absorption spectrum with water

● test tube baby with water

●A variety of high performance liquid chromatography, ion chromatography water

● Other various laboratory water and medical water.

The main process of ultra-purified water quality

Common impurities in natural water include soluble inorganic substances, organic matter, particulate matter, microorganisms, soluble gases, and the like. Ultrapure water machine is to remove these impurities as thoroughly as possible.

At present, the commonly used methods for purifying water quality include distillation, reverse osmosis, ion exchange, filtration, adsorption, and ultraviolet oxidation. Ultrapure water machine can generally divide the purification process of water into 4 steps, pretreatment (primary purification), reverse osmosis (production of pure water), ion exchange (which can produce 18.2MΩ.cm ultrapure water) and terminal Treatment (production of ultrapure water meeting special requirements).

Pretreatment

Since the pretreated water will be further purified by reverse osmosis, impurities that have an effect on the reverse osmosis membrane must be removed as much as possible; mainly including large particulate matter, residual chlorine, and calcium ion magnesium ions. It is to be noted here that different processing units must be provided in a targeted manner depending on the difference in influent water quality. Most water purifier manufacturers are not very good at helping customers solve this problem, which will lead to subsequent purification not achieving the desired results and shortening the life of major components such as reverse osmosis membranes and ultra-purification columns.

In order to solve this problem well, the design of precision filter, activated carbon adsorption filter and softening resin to remove large particles, residual chlorine and calcium ion magnesium in water to achieve better pretreatment effect.

The timely replacement of pre-treatment consumables (the price is relatively low) is very important for the long-term stable operation of ultra-pure machines and the protection of core components.

Reverse osm

Reverse osmosis is the use of a high pressure pump to provide a high pressure solution with a pressure greater than the osmotic pressure difference, water molecules will be forced through the semipermeable membrane to the low concentration side, reverse osmosis can filter out 90%-99% including inorganic ions Most of the pollutants inside, because of its superior purification efficiency, reverse osmosis is a very effective technology for water purification systems, because reverse osmosis can remove most of the dirt, so it is often used as a front-line treatment. It can significantly extend the use time of the deionization column.

In view of the fact that reverse osmosis is very important in the purification process of water quality and the replacement price of reverse osmosis membrane is high, we suggest that users must choose ultra-pure water machine with protection function for reverse osmosis membrane.

In order to maximize the service life of the reverse osmosis membrane and improve the filtration efficiency of the reverse osmosis membrane, a unique technology is adopted, combined with an advanced reverse osmosis flow restriction design, the flow valve is limited in the effluent, so that the reverse osmosis membrane is always immersed in the water, so as not to It affects life due to drying out. Extending the life of the reverse osmosis membrane is to ensure the quality of the effluent, and also to improve the cost performance of the ultrapure water system.

The quality of the reverse osmosis membrane has a great influence on its service life and the service life of the ultra-purified column, so we recommend that users pay attention to the brands of reverse osmosis membranes, such as Dow and GE.

Ion exchange

Ion exchange is the exchange of positive ions in water with H+ ions in the ion exchange resin, and the negative ions in the water exchange with the OH- ions on the ion exchange resin to achieve the purpose of purifying water. By removing ions by ion exchange, it is theoretically possible to remove almost all of the ionic species, and at 25 ° C, the effluent resistivity reaches 18.2 MΩ. Cm. The quality of the ion exchange effluent water depends mainly on the quality of the ion exchange resin and the exchange efficiency of water and resin in the exchange column.

The quality of the ion exchange resin has a direct impact on the effluent quality and service life of the ultrapure water machine, so we recommend that users pay attention to the resin brand, such as the loading amount of the Dow and Rohmha ion exchange resin. The service life is proportional to the relationship.

Terminal processing

Ultra-pure water, which is ultra-low organic, aseptic, and non-heat source, is produced mainly according to the special requirements of customers. There are various treatment methods for different requirements, such as ultrafiltration filtration method for removing heat source, dual-wavelength ultraviolet oxidation method for reducing total organic carbon (TOC) in water, and microfiltration to remove bacteria.

Ultrafiltration (UF) film is a molecular sieve, which is based on the size of the solution, allowing the solution to pass through a very fine filter to achieve the purpose of separating molecules of different sizes in the solution. The heat source content in ultrapure water can be reduced to 0.001 EU. /ml below. The dual-wavelength ultraviolet oxidation method can utilize photooxidation of organic compounds to reduce the total organic carbon concentration in ultrapure water to below 5 ppb.

Conclusion

Ultra-pure water machine can produce high-quality ultra-pure water is only the first step. For users, it is the most important problem to maintain high water quality as long as possible.