The waste liquid contains both calcium chloride and sodium chloride; how can effective separation be achieved?
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There is 8 tons of wastewater per hour, containing 10% sodium chloride and 10% calcium chloride. It is necessary to separate sodium chloride from calcium chloride; the separated sodium chloride should contain less than 5% calcium chloride, and the separated calcium chloride should contain less than 5% sodium chloride. What ideas do everyone have?
Neutralization with caustic soda followed by filtration yields calcium hydroxide, which is then converted into calcium chloride using hydrochloric acid.
Sodium chloride and calcium chloride are extremely cheap; using chemical reaction methods for separation would definitely result in huge losses. The stepwise crystallization method is the most suitable approach for this system – the purity of sodium chloride can exceed 98%, while that of calcium chloride can reach 96%. For more details, please contact me at myben@126.com
The wastewater is directly clarified and then used for salt production, resulting in the precipitation of sodium chloride; the remaining concentrated waste liquid mainly consists of calcium chloride. It should be calcium salt co-production~
At such a high concentration, chemical methods definitely won’t work – the costs are too high. Physical methods would be better; using membranes or evaporation crystallization should work.
Are there no other impurities besides sodium chloride and calcium chloride?
Neutralization is certainly an option, but it won’t yield the desired results. In this case, electrodialysis can be used to separate the salts; it’s feasible, and I can prepare a plan for you. WeChat: *n928866853
Dry in the sun; once dried, steam it. After steaming, let it cool, and then take it out. By utilizing the principles of phase diagrams, natural forces are first used for natural concentration ； After that, evaporation concentration is carried out; the temperature is controlled to allow crystallization to occur, and finally the crystals are separated, washed, and purified.
With 10% calcium chloride and 10% sodium chloride, the total TDS of the wastewater is 20% (200,000 ppm); can it still be concentrated using electrodialysis? It should only be possible to undergo direct evaporation crystallization
This concentration does not offer good economic efficiency, so it is not recommended