Advanced treatment and reuse of wastewater
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It involves the reuse of wastewater from a biotechnology company, and the water quality parameters are as follows: the treatment capacity of the facility (for the treated water) is 500 tons per hour. The parameters of the incoming water are COD of 100–150 mg/L, suspended solids of 70 mg/L, phosphorus content of 15–20 mg/L, and conductivity of 40,000–45,000 us/cm. Does anyone here have experience with this type of situation? I would appreciate any insights you can share!
The conductivity is between 40,000 and 45,000 us/cm. Is the unit correct? A value this high means that salt can be obtained by direct evaporation; I wonder which type of salt has the highest content
The conductivity is way too high; if it passes through the membrane, it will get clogged within a few days. Use electrodialysis instead.
This salt content is also too high; what’s the TDS level? It’s necessary to first reduce the levels of COD, SS, and P. I suggest starting with MBR, and then using membranes as well; it is likely that these will be desalination membranes, depending on the TDS level.
Evaporation can be used to separate out most of the salt first; however, this method is energy-intensive. Alternatively, desalination membranes can be employed. As for phosphorus, it can be treated by adding lime.
The organic wastewater is pumped by an inlet pump to a counter-current bed two-chamber ion exchanger, which is used to remove organic substances from the water, thereby reducing the concentration of large-molecule anionic organic compounds in the water and protecting the electrodialysis cathode membrane.
It’s almost impossible to reuse it in one step
This salt content is also too high; what’s the TDS level? It is necessary to reduce the levels of COD, SS, and P first. I recommend starting with MBR, and then using membrane technology; it is likely that desalination membranes will be used here, depending on the TDS level. The organic-containing wastewater is pumped to a counterflow bed dual-chamber ion exchanger, which is used to remove organic substances from the water, thereby reducing the amount of large molecular anionic organic compounds in the water and thus protecting the electrodialysis cathode membrane. If there are toxic substances present, precipitation and other treatment methods should be applied first
After reading the replies above, I’m a bit confused: (1) The salt content is very high; considering the conversion between conductivity and salt concentration, it seems that your salt level is around 25,000 mg/L. So high – it’s basically at the level of brackish water and seawater. Of course, there may be significant differences among the salt-containing types. Is it worthwhile to use this concentration and apply a film-coating treatment just to remove COD and phosphorus? (2) Someone upstairs mentioned using ion exchange to remove organic matter, and I think it could be a viable option. However, salt is detrimental to many adsorption processes, and since the type of organic matter is not clear, determining which type of exchange to use may require experimental efforts. (3) I’m not sure what the owner’s goals for reuse are; if it’s necessary to remove COD, salts, and phosphorus as well. It’s likely to be more expensive if it’s estimated. . .