1780 North Cedar Ave. Owatonna, MN 55060 507.451.8537

Tank-Side Coalescers

Tank side coalescing oil skimmers sit outside the tank and, unlike belt or disk skimmers, remove emulsified oils as well as the free floating oils. They can run continuously without overflowing, keeping the coolant moving and aerated. Over time a tank side oil skimmer will remove more oil than a belt or disk skimmer. Coolant Consultants offers four different brands of tank-side oil removal systems: Keller, PhaSep, and Zebra.


When setting up a coalescer, the fluid return hose should be located as far away from the oil pick-up as possible.  It can also be used to “push” the tramp oil towards the pick-up unit.  The oil pick-up needs to be positioned where the most oil is present if possible.  The pick-up also needs to float freely with changes in fluid level.  It’s usually best NOT to locate the pick-up near the pumps.  

When setting up air powered coalescers, the air regulator should be adjusted so the pump is running really fast, then close the small air ball valve before the pump, reducing the air flow until the pump is running as slow as possible to maintain flow and suction at the pickup device.  If you adjust the pump speed with the regulator, the pump can stall out or run too fast with slight changes in shop air pressure.  The filter should be changed when flow becomes restricted.  Sometimes the filter doesn’t look dirty, but has become “blinded off” by fine residues or contaminant coating.

All oil skimming devices should only be run when oil is present on surface.  Timers should be used to activate the device after the oil has settled to the surface.  Running them 24/7 just wears the motors out prematurely.  Coalescers can be run periodically even if oil is not present on the surface in order to keep the coolant moving on an intermittently run machine.



Abanaki Oil Boss Tramp Oil Skimmer with Surface Sucker™
Abanaki Oil Boss Magnetic Mount Tramp Oil Skimmer picks up hard to remove oils that conventional skimmers leave behind.
Keller ECO Tramp Oil Coalescer
The economical Keller ECO tramp oil coalescer with electric pump works well for coolant with minimal solids content.
Keller TKO-6 with CLO-1 Magnetic frame
The air-driven Keller TKO Tramp Oil Skimmer rapidly sweeps out tramp oil, cleaning and aerating the entire sump.
Keller #RSM-3 Inlet Device, 3-float, large
Keller magnetic frame, additional inlet devices, and replacement filters
PhaSep Coalescers
Positive coolant flow, superior float design, and simple oil separation are key success factors of the PhaSep Coalescer Tramp Oil Removal Systems. PhaSep Coalescers are designed with all steel construction; no media to replace or dispose!
Zebra Z17 Muscle™ Flexor™ Coalescer
The Zebra Muscle™ Flexor™ Coalescer Z17 tramp oil separator will aerate, filter, and separate coolant from tramp oil so that your coolant lasts longer. Can be run 24 hours a day - 7 days a week without overflowing tramp oil container!
Zebra Hammerhead™
Zebra Z17 Muscle™ Flexor™ intake attachments, drum dolly, and accessories