What is the difference between using ion exchange resin to produce desalted water and using produced water and domestic water as raw water to control the end of bed operation?
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Please tell me: What is the difference between using ion exchange resin to produce desalted water and using produced water and domestic water as raw water to control the end of bed operation? Producing water conductivity: About 200us/cm, Ca2+: 30-40mg/l Domestic water conductivity: About 400us/cm, Ca2+: 110mg/l。
The conductivity of domestic water provided by the poster is 400us/cm> the conductivity of production water is 200us/cm. I'm a little confused, why does production water contain salt > domestic water contains salt? Where does the water come from? Regarding control, ion exchange generally adopts sequence control, which is to calculate the running time of anion and cation beds and the total regeneration time based on your water quality parameters. When using a multiple bed unit system, the resin filling amount of the anion and cation exchangers must be adjusted so that the running time of the anion exchanger is slightly longer than the running time of the cation, and the two are roughly equal. Then use PLC or DCS to control the operation and regeneration steps according to the calculated time. When it fails, a conductor should be installed behind the cathode bed. Because the anode bed fails first, it will leak Na, and the cathode bed provides OH-. As long as a little Na is leaked, the cathode bed water will have NaOH. Since OH- has good conductivity, the conductance rises rapidly and the reaction is quick. This is one of the reasons why the cathode bed runs longer than the cathode bed.
There are two types of water produced by our company's water plant, one is production water and the other is domestic water. The produced water is provided for desalination and circulating water use in the factory. Its alkalinity is low (around 20) and its salt content is also low. Domestic water is for human consumption, but no produced water is produced during overhaul, so the desalination system also uses domestic water. When our ion exchange resin uses domestic water, the batch size is around 4,000 (the designed water capacity of the double-chamber boiling floating bed is 240t/h). The conductivity has not increased, and the silicon has seriously exceeded the standard. ； However, when using produced water to produce water, the batch size can reach 10,000t/h, and the end point of the operation is based on conductivity. Our online monitoring only has the conductance at the cathode bed outlet, and silicon can only be analyzed manually, so it is difficult to control the end of the run.