Why do I need post-processing of permeate?
Particularly noteworthy are the stages of post-processing or final correction of permeate. As part of household reverse osmosis systems, these stages are implemented using various post-filters installed on the supply line of purified water from the storage tank to the tap. There are various options for post-filters with which manufacturers complete household reverse osmosis systems, but in practice they all perform three different functions:
1. Correction of the taste of water;
2. Ensuring the microbiological purity of drinking water;
3. re mineralization and pH adjustment.
Let us consider in detail each of the problems solved by various options for post-processing permeate in household reverse osmosis systems or in some industrial Ro plant .
Almost all household osmosis uses post-treatment of permeate with activated carbon obtained from coconut shells. For this purpose, the reverse osmosis system is equipped with the so-called post-carbon – encapsulated filter, filled with high quality coconut activated carbon. When water passes through this filter, the correction of important organ oleptic indicators of water quality – taste and smell occurs. Post carbon can improve the taste of water for those consumers who find the permeate to be tasteless, and also eliminates possible odors associated with storing water in the storage tank.
The question of the need to ensure microbiological purity of water after a storage tank in household reverse osmosis has arisen relatively recently. To solve it, routine maintenance of the system with flushing the tank with disinfecting reagents is usually carried out. The problem of the presence of microorganisms in water can be solved using certain methods of post-treatment of water.
One such method is the disinfection of water using ultraviolet radiation. This physical method, used for many years, is not only highly effective, but also has no negative effect on the chemical composition of purified water. Until recently, the widespread use of UV was significantly hindered by the high cost and energy costs of the method, today a large assortment of lamps of different capacities, including LED (UV– LED) disinfectants, allows its use in a variety of fields. UV lamp is almost an ideal option for household water treatment. Compact and ergonomic, they are easy to install in cleaning systems, ensuring trouble-free operation and effective disinfection of water. Another physical method of water disinfection that can be used in local water treatment is ultra filtration. The essence of water disinfection using ultra filtration is that when water passes through a semi permeable membrane with a pore size of 0.001 to 0.1 μm, various impurities are retained: colloids, organic substances, algae and most microorganisms. More recently, this method was mainly used to remove colloidal impurities and suspensions on an industrial scale. Now, interest in its use for removing microorganisms in household water treatment has significantly increased.
Today, various companies produce compact, easy-to-use ultra filtration cartridges, which are not inferior to UV lamps in terms of disinfection efficiency. Cartridges of this type are recommended to be used after the storage tank of household reverse osmosis systems for the post-treatment of water from possible microbiological contamination.
The salinity of household osmosis permeate does not exceed 15–20 mg / l. In recent years, the global medical community has recognized that de mineralized water does not harm human health. However, the taste of such water differs significantly from the usual. It is to ensure the possibility of choosing the composition of purified water that there is such an option for household reverse osmosis systems as a mineralizing post-filter or mineralizer. Mineralizer in the General case is a filter filled with crumbs of various natural minerals. Reverse osmosis permeate, characterized by a pH of 5.8-6 and low salinity, when in contact with such crumbs, slowly dissolves it and is saturated with salts of calcium, magnesium, sodium and potassium to a level of 50-100 mg / l. In addition, the permeate acidity is corrected – the pH value rises to 6.5–7
For further information click here : Ro plant price in Pakistan
watertreatment 