Tips for Oil Water Separators (OWS)
/Oil water separators (OWS) are a vital part of protecting the environment from hydrocarbon releases. Although typically out of sight and mind, they quietly do their part when properly maintained. The coalescing media is the essential element for attaining acceptable oil discharge limits. However, the coalescing media is also most susceptible to solids obstructing proper oil separation. When solids and hydrocarbons are not removed regularly, they can cause unwanted sludge buildup in the system and poor effluent characteristics.
In reviewing a number of OWS manufacturer designs and maintenance procedures, it’s recommended to perform yearly maintenance to recover released oils, dispose of fluids according to environmentally complaint methods, and clean the coalescing media. Grit and debris accumulations should not exceed the maximum allowable depth specific to the OWS design. Excessive solid build up should be monitored particularly after heavy rainfall events. Upon removing the oil and solids, clean the coalescing media with water. After maintenance is completed, the OWS should be filled with fresh water. As a final step, mark your calendar for checkup in another year.
Recommended annual OWS maintenance procedures:
Stop influent flow into the OWS.
Dispose of separated oils per regulatory procedures.
Drain the water from the OWS.
Measure and record the depth of solids, confirm depth is acceptable according to OWS literature, and remove the solids.
Clean the coalescing media with water spray according to manufacturer recommendations.
If cleaning in place, remove debris from the tank using a vacuum.
If cleaning outside of tank, ensure contaminated water is properly contained without disposing to ground.
Inspect tank interior and repair coating as needed.
Once debris is removed and the coalescing media has been cleaned, refill OWS with clean water.
For additional information contact us:
Andrew Wengerd, PE, CFPS, LEED AP | andrew.wengerd@ssmgroup.com