Treatment of high-concentration sodium sulfate wastewater
Thread Content
The wastewater from our company contains a high concentration of sodium sulfate, around 20 g/L; all other components are within the allowable emission limits. As we operate on a small scale, the amount of wastewater generated is approximately one ton every two weeks. I have a few questions now, and I hope the experts here can help answer them. Thank you. 1. What is the simplest and most effective method of treatment? 2. Is it necessary to use equipment for wastewater treatment? Is it really essential when the volume of wastewater is small? 3. Is it necessary to recover this concentration of sulfates? I’ve heard that barium or calcium can be used to precipitate them and then recover the precipitate. I have no experience with wastewater treatment issues, so I hope you can help me understand this. If possible, please also give me some suggestions for treatment. Thank you.
Freezing crystallization can be used to recover sodium sulfate, but the concentration here is not high and the amount of water is also small – why not simply dilute it and discharge it?
Only one ton per half month; it’s sufficient to pass it through cooled brine to lower the temperature and induce crystallization, followed by filtration.
I’ve seen some people say that it’s best not to dilute the emissions; the amount of water used is not very large at the moment, but if production volume increases in the future, these same problems will arise. So I want to figure this out as well.
Evaporating water using this method does indeed work, but the question is whether it’s necessary – only one ton per half month. If MVR is used with a minimum processing capacity of 200 liters per hour, it seems like a waste as well. It requires an investment of over 200,000 yuan; it’s simpler to just use chilled water. .
Then freeze crystallization it is~~ For sodium sulfate, evaporation is not economical
At a concentration of 2%, direct evaporation would likely be the most economical option, or one could consider further concentrating it before carrying out evaporation crystallization.
There are many methods； There are various options available, taking into account the scale of processing, the final requirements for the output, and investment control
Can it be treated directly with calcium or barium salts for precipitation, given this amount?
It only produces 1 ton in half a month; just build a drying pond and dry it there