Regarding the replacement of the polishing resin, if the customer requires it to be carried out under the condition of guaranteed production, then the resin tank can only be replaced one by one on site. The procedure and precautions for on-site replacement are as follows.
(1) Disassembly step: Since each resin tank is separate for water inlet and outlet, the water inlet and outlet are equipped with union ball valves. When replacing on site, first close the inlet and outlet ball valves of a resin tank, and put the underside of the inlet and outlet ball valves with the polishing mixed bed. Remove the live connection of the connection port, remove the resin tank, disassemble the top port of the resin tank, use a soft water pipe to use the principle of siphon to drain the water in the resin tank into the ditch, when the water is drained and there is not much resin inside Pour down the resin tank to pour out all the remaining resin, and then use a hose to connect the EDI product water sampling valve to flush the resin tank until the resin tank is flushed.
Steps and specifications
1. Filling: The polishing resin is a mixture of hydrogen type strong acid cation exchange resin and hydroxide type strong alkaline anion exchange resin. When filling, the issues of cleanliness and delamination need to be considered. ①Pipe and water tank body must be flushed thoroughly and clean before filling; the system generally has a water tank before polishing the mixed bed. The water tank, pipes and various equipment need to be thoroughly inspected and cleaned to prevent organic matter from entering the resin bed and causing bias flow of the resin bed And pollution to the resin bed; ②When filling, the ultra-pure water for cleaning the mixed bed tank should be thoroughly drained to ensure no stratification; ③Ultra-pure water must be used when flushing (15M or more is recommended); ④If necessary Filling with resin by hand, be sure to wash your hands, and do not bring grease into the resin tank; ⑤If you change to resin, you must completely clean the tank and the water trap, and there must be no old resin residue on the bottom of the tank, otherwise these use The spent resin will pollute the water quality.
2. The O-ring and fasteners used must be replaced regularly. At the same time, the relevant components must be checked each time they are replaced. If they are damaged, they must be replaced immediately. Check the water trap, if it is blocked, it should be cleared.
3. When using FRP tank as resin bed, the water collecting pipe should be left in the tank before filling with resin. In the process of filling the resin, the water collection pipe should be shaken from time to time, so that at the end, the position of the water collection pipe can be adjusted and the upper cover can be installed. If the resin is filled first, it will be difficult to insert the water collection pipe. If you must fill the resin before inserting the water collection pipe, you can place the FRP tank filled with resin horizontally on the ground, roll the barrel slowly to loosen the resin, and then slowly insert the water collection pipe into the resin (this method does not Recommended).
4. After the resin is filled and the pipeline is connected, the vent hole at the upper end of the tank should be opened first, and ultrapure water should be slowly introduced until the vent hole overflows and no air bubbles are generated. Water; or other methods, be sure to exhaust thoroughly.
(2) The basic requirements for water inflow: resistivity 15M or more (for our system), PH value is between 6.5-7.5, and the content of CO2 that needs to be controlled should be basically no (focus on controlling PH and resistance to achieve); The division polishing mixed bed is generally used after the nitrogen sealed water tank, so the water quality inspection point should be placed in front of the polishing mixed bed instead of the EDI production water pipe. If the above standards are not met, please do not install and run the polishing mixed bed.
(3) Polishing mixed bed flow rate control: It is recommended to control it at 40m/h-60m/h, the higher value is more ideal, and even higher flow rates can be designed. Too low a flow rate will affect the service life of the resin; therefore, you should first understand the water production of the polishing mixed bed when running the polishing mixed bed. Too low water production is more likely to affect the service life of the polishing resin. Thoroughly check the water distribution, pipes, conductivity meter, etc. of the polishing resin bed to ensure that the polishing resin bed is operating normally. After the polishing resin is wetted, continuous operation is the most ideal. It cannot be used for a long time, which will cause organic matter to contaminate the resin; if there is a shutdown, it must be cleaned with ultrapure water on a regular basis and the tank body must be kept The high purity of the water ensures the moisture in the water tank. Polishing resin is an expensive and delicate equipment consumable, which needs to be operated in strict accordance with the use specifications.
(4) After the above conditions are met, the new resin needs to be rinsed for one hour before the water is drained.