Application and attention of ion exchange technology of water softener

The application of ion exchange technology of water softener and the points for attention the hardness of water mainly refers to the total content of calcium (Ca2 +) and magnesium (Mg2 +) Both production water and domestic water have certain requirements on hardness index In particular, if the hardness of water used in boiler and water heater is too high, scale will form on the heat exchange surface, thus reducing the thermal efficiency and increasing fuel consumption The hardness of water mainly refers to the total content of Ca2 + and Mg2 + Both production water and domestic water have certain requirements on hardness index In particular, if the hardness of water in boiler and water heater is too high, scale will be formed on the heat exchange surface, so as to reduce the thermal efficiency, increase fuel consumption, and even damage parts and cause explosion due to local overheating on the metal wall Therefore, the boiler and water heater should be softened; when the raw water containing calcium and magnesium ions passes through the resin layer of the water softener, the calcium and magnesium ions in the water will be replaced with the sodium ions in the resin, and the resin will absorb the calcium and magnesium ions and the sodium ions will enter the water, so the water flowing out of the water softener is the softened water with the calcium and magnesium ions removed With the continuous exchange process, Na + in the resin is replaced completely and loses the exchange function after it reaches saturation At this time, the resin must be regenerated with the soft water salt (NaCl) solution, and the calcium and magnesium ions adsorbed by the resin are replaced The resin reabsorbs the sodium ionon, and the softening exchange capacity is restored The purpose of soft water is to remove the hardness components that can form scale in water, such as calcium and magnesium ions, and other high price metal ions, such as iron, aluminum, manganese, etc (due to the small content, although scaling can be omitted), and 90% of household washing and bathing water in developed countries have used soft water The softener is equipped with softener resin This artificial ion exchange resin has soft mineral sodium, which can exchange with hard minerals such as calcium and magnesium dissolved in water However, sodium does not accumulate on the surface of the object in the form of scale, so it does little harm to the object in contact with it Resin is a porous, insoluble exchange material In the modern water softener, there are millions of tiny plastic balls (beads), all of which contain many negative charge exchange positions that absorb positive ions When the resin is in a new state, these charge exchange positions are occupied by positively charged sodium ions When the water containing calcium and magnesium ions passes through the resin storage tank, the calcium and magnesium ions contact the resin beads and replace the sodium ions from the exchange position After ion exchange, calcium and magnesium ions are adsorbed on the resin in the softener, and the outflow water becomes soft After the role of the water softener Zui, all the resins are full of calcium and magnesium ions, they can no longer work, but need to be regenerated The softener uses the ion exchange technology to exchange the functional ions on the resin with the calcium and magnesium ions in the water, so as to absorb the excess calcium and magnesium ions in the water, so as to remove the scale (calcium carbonate or magnesium carbonate) The regeneration of softener resin is carried out with dilute solution of sodium chloride and water In the regeneration process, first stop the working water flow of the softener, mix the brine from the brine tank with another dilution water flow, the dilute brine solution flows through the resin, and contacts with the resin with calcium and magnesium ions Although the electricity of calcium and magnesium ions is stronger than that of sodium ions, the concentrated salt solution contains millions of sodium ions with weaker charges, which has the ability to take calcium and magnesium ions with less algebraic orders In this way, when the calcium and magnesium ions are replaced and exchanged, the resin is regenerated and ready for the next softening work So it goes back and forth Precautions for the water softener 1 It should be avoided to place the water softener near the heat source or take necessary heat insulation measures, and it is strictly prohibited to connect it to the hot water pipeline or the pipeline that may generate hot water pouring back 2 When the raw water does not meet the municipal tap water standard, such as large silt content, excess chlorine, etc., a pretreatment device shall be installed in front of the water softener 3 There should be enough space between the drain pipe of the water softener and the drain floor drain to prevent siphonage 4 After the installation, the valve head shall be turned to the backwashing position first, and then the water inlet valve shall be opened, so as to discharge the protective liquid of resin into the sewer, and then start the immediate regeneration procedure, and pay attention to observe whether each procedure operates normally during regeneration 5 Edible salt (solarization salt) shall be used for the water softener, and insoluble impurities shall be less than 1% It is forbidden to use salt containing various additives 6 During the operation of the water softener, the user should pay attention to check the salt content in the salt tank The salt content should reach one fifth of the height of the salt tank each time When the height of the salt surface is less than one fifth, the salt should be added in time 7 Sometimes a salt bridge will be formed in the salt tank, that is, a space will be formed at the bottom of the salt layer In the regeneration process, salt cannot be dissolved in the water to form a salt solution, the invalid resin will not be regenerated, and the water softener will not produce qualified soft water Users should always check whether there is a salt bridge at the bottom of the salt box If there is a salt bridge, please mash it 8 In case of long-term shutdown (or unstable water pressure), in order to prevent water hammer, the main valve must be closed to cut off the water supply of the water softener; When in use, the electric control type must be connected to the power supply first to adjust the time 9 The optimal water inlet pressure of the water softener Zui is 0.2 ~ 0.5MPa, and the pressure relief device must be installed if it is higher than 0.5MPa 10 Before installation, the designer must design the size and installation position; the user needs to keep the floor drain; the electric control type needs to reserve the power source