What consumable technologies have been improved in ultrapure water machines to ensure better operation?

     The ultrapure water machine adopts reverse osmosis technology for water treatment. In order to ensure its better operation, in addition to improving the basic material guarantee of the pipes used in the reverse osmosis equipment, stainless steel and UPVC used in the equipment, it can also be used in reverse osmosis pure water. The first purification of tap water is carried out before the water machine. Make it meet the quality requirements of RO water purification, protect the reverse osmosis RO membrane, make the RO operate normally and prolong its life. The improvement of ultrapure water treatment can be carried out from the following components.

(1) The selected meltblown filter element

The melt-blown filter element can filter out suspended particles larger than 5-10μm in water. Its pore size is uneven, and the number of each pore size is normally distributed, but it is a large value at 5-10μm ( peak). Its filament diameter and pore size are related to the melt temperature, indoor air temperature and humidity, airflow size and speed, receiving distance and other factors. From the outside to the inside of the melt-blown filter element of good quality, the pores between the PP fiber filaments gradually become smaller and smaller, forming a progressive density structure. The filtered suspended impurities are not only on the surface of the filter element, but also inside the filter element, and the filter element is polluted. Large quantity and long service life. However, the manufacturing equipment is complex and expensive, and the price of the filter element is also expensive.

(2) Use ceramic filter element

Although the melt-blown filter element is very cheap, it is a one-time use, and the melt-blown filter element can be replaced by a ceramic filter element. Although the price of the ceramic filter element is relatively expensive and the one-time investment is relatively large, it can be cleaned repeatedly and has a much longer service life. As long as the whole machine is designed to facilitate the assembly and disassembly of the filter element, it is a good choice to use a ceramic filter element to replace the melt-blown filter element. The raw material of the ceramic filter element should be diatomite, which is fired in a tunnel kiln. It feels light in weight and has good water absorption. The quality of such a ceramic filter element is good. The poor quality ceramic filter element has a relatively rough and uneven surface, and the diatomite material has many impurities and heavy hand feel. That is to say, this is the reason. Another simple method is to drop water on the surface of the ceramic filter element, which should be inhaled quickly, and no water droplets remain on the ceramic surface, indicating good hydrophilicity and high porosity.

(3) Microfiltration-ultrafiltration double-membrane method

In some water purifier manufacturers, the three-stage pretreatment adopts the mode of hollow fiber microfiltration-granular activated carbon-hollow fiber ultrafiltration, which is also a good combination. The first grade adopts PVDF hollow microfiltration membrane with reinforced support to filter out suspended solids and bacteria. If the membrane is dirty, it can be removed and washed without breaking; the second grade activated carbon removes residual chlorine, organic matter, colloid, odor, etc.; the third grade PS The hollow ultrafiltration membrane can further remove suspended matter, microorganisms, colloids, etc. Such careful pretreatment can not only prolong the service life of the RO membrane, but also improve the recovery rate of pure water.

(4) Activated carbon fiber filter element

Activated carbon fiber (ACF), the raw material is viscose-based fiber or polyacrylonitrile-based fiber, the fiber diameter is about 10-20μm, the average pore size of the former is 17-26A, and the latter is 10-20A. Activated carbon fibers are often made into felts with a thickness of 1 to 5 mm. It has more micropores than granular activated carbon, a larger specific surface area (700 to 1600 m2/g), a larger adsorption capacity (2 to 6 times higher), and a faster adsorption speed. It is fast and has good regeneration performance, that is, it can be desorbed after the adsorption is saturated, take out the filter element and treat it with hot water, wash the adsorbed organic matter and colloid, the desorption speed is fast, and the filter element can be reused, that is, the regeneration of the filter element. But the disadvantage is that the price is more expensive and there are fewer production enterprises. It is also easy to multiply bacteria in use. In addition, some poor-quality activated carbon fibers have a small adsorption capacity and are easily saturated after use, and it is very troublesome to desorb and regenerate or replace the filter element. Therefore, at present, the use of activated carbon fiber filter is still relatively small.

(5) Granular activated carbon filter

Activated carbon has a great effect on removing residual chlorine, adsorbing colloid and organic matter, removing odor, and protecting reverse osmosis membrane. Its performance is mainly reflected in the ability to remove COD. The ability to remove COD is related to the flow rate and contact time design of the water purifier. According to the standard of JB/T2932 "Technical Conditions of Water Treatment Equipment", the residual chlorine in the water is removed (the residual chlorine in the effluent Ag2+>Ag+, the growth of bacteria is suppressed and the silver ions in the water do not exceed the standard.

The above are the consumable technologies for ultrapure water machines that can be improved, hoping to help everyone use this equipment in a better and more energy-efficient manner.