How can I remove meat particles and salt from wastewater?

[briandestefano]

Sorry about the vagueness of my previous post. I am working on the treatment of the wastewater for a salmon smoking facility in upstate New York. The salmon is delivered in fillets so there is no gutting going on or anything like that. The facility currently discharges there wastewater into a ditch witch leads to a nearby small river. I am looking treating the water and continuing to discharge it into the river or into an absorption field similar to a rural residential septic field. I am trying to figure out how to remove whatever fish particles get into the wastewater while washing and also what to do with the salt used for preservation. For the fish meat I am thinking about filtering the water or allowing the pieces to settle out, is this reasonable? And for the salt, I am worried about discharging it into a freshwater river. Any help would be much appreciated.

 

[civilperson]

Reverse Osmosis Membrane can do what you want.

 

[briandestefano]

shouldn't the fish meat particles be removed from the wastewater first?

 

[bimr]

The Standards of performance for new sources list discharge standards for BOD5, TSS, Oil and grease, and pH. So you probably do not have to worry about salt.

It is probably going to be less expensive to keep the materials out of the wastewater stream, then to try to remove the materials from the wastewater.

The selection of wastewater treatment technology is going to depend on the size of the food processing operation, which you have not posted.

Food manufacturing plants usually incorporate some type of DAF unit to remove suspended matter as well as FOG. You can probably install a DAF and then filter the DAF discharge. DAF is the traditional wastewater treatment technique for the food industry.

The DAF unit is probably the least expensive technology.

Removing dissolved salts would require some type of reverse osmosis treatment and will be so ridiculously expensive that your client can not afford to even think about it. Don't even waste your time with the salt removal. Try to keep the salts out of solution. Note that it is very, very rare when there is a TDS limit on the discharge.

 

[Watthour]

The DAF, a supplementary fine grit removal system (rotary drum screen or similar) and membrane bioreactor would also be worth investigating. The DAF would keep the bulk of inert solids from the waste stream as bimr advises, the drum screen would keep buoyant particulates from the process, and anoxic/aerobic bioreaction should clean up the balance, yielding only sludge and effluent below the ten-state standards. Any idea of the MGD rate or BOD, FOG, pH, MLVSS? I know the NY and NPDES requirements, but would need more data on your effluent to suggest anything concrete. Salinity is acceptable to a point, so unless there is added NaCl, the runoff from packed fillets might not be a significant issue for a drip irrigation or stream discharge.