The chloride level in the raw water is too high; are there any reliable processes with low investment for raw water treatment?
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The chloride level in the raw water is too high; are there any reliable processes with low investment for raw water treatment? During the dry season, the chloride concentration in reservoirs can reach around 200. The current water treatment process for raw water consists only of a grid reaction tank + inclined sedimentation tank + V-type filter. Are there any other processes?
The process you mentioned is intended only for flocculation and sedimentation, that is, it mainly serves to remove SS; chloride ions already exist in ionic form, and additional desalination equipment such as RO membranes or resins is required to remove them；
Chloride ions cannot be treated with RO devices, as it will damage the RO membrane; activated carbon adsorption is the best option in such cases
You’re an amateur. Chloride ions are not active chlorine; they have no effect on RO membranes. If chloride ions could damage RO membranes, desalination would be pointless. Active chlorine is the factor that damages membrane modules.
Precipitation or flocculation cannot reduce the chloride ion concentration, as chloride ions are very stable in water. Excess chloride ions can only be removed through reverse osmosis, electrodialysis, or ion exchange.
Residual chlorine can oxidize the reverse osmosis membrane; therefore, a reducing agent should be added before the safety filter, and an ORP meter should be installed before the high-pressure pump
RO reverse osmosis, but the cost is not low
At the moment, reverse osmosis is the only option. Some time ago, I learned about \"chloride reducers.\" The supplier sent me samples, and I conducted tests in the laboratory; as a result, it was confirmed that the chloride ions level had indeed decreased. But it’s suspected that it might be blocked, rather than the chloride ions actually decreasing. The manufacturer claimed it was a high-tech, nano product; I feel like I was deceived.
There are now chlorine removers, as well as other methods for removing chloride ions, but I think nanofiltration or reverse osmosis is the more reliable option. Although the initial investment is high and the operating costs are significant, the overall benefits are considerable.
Concentration and enrichment are carried out first, raising the chloride ion concentration to a certain level (a high concentration), followed by dechlorination. Extraction methods, such as multi-stage counter-current extraction, can be used to remove the chloride ions. The investment cost for the equipment is low, and the treatment costs are also low. The final product can be sodium chloride or ammonium chloride; ammonium chloride is a fertilizer with a high added value and can be used as a fertilizer for farmland. As a result, there are no costs associated with waste disposal. The chloride ion concentration in the recycled water can be reduced to below 100, meeting the requirements for normal production