Below Grade
0-5000 GPM

Recommended when deep burial and/or drive over conditions are required. (Usually gravity feed).

OWS TECH’s HB-Series oil water separators are design specific and meet or exceed exacting standards. Our performance proven separators are made from the highest quality fiberglass to ensure structural integrity and use a unique high efficiency coalescer (HEC) pack to remove free non-emulsified hydrocarbons with a specific gravity less than 0.95. Our (HEC) packs unique random tube matrix flushes solids and removes oil droplets down to 20 micron size with an effluent discharge quality of 10ppm or less. The HB-Series by design has a low maintenance factor and is easily serviceable due to its large solids collection area and light weight removable (HEC) packs. Units are available in either single or dual wall construction with flow rates up to 4200 gpm. With our extensive line of below grade oil water separators ranging from 4’ to 10’ in diameter we’re sure to have one that meets your specific application.

Features and Benefits:

  • Cost effective
  • Pre-packaged
  • Rustproof/Corrosion resistant
  • Lightweight
  • Made with our unique (HEC) pack
  • 30 year structural warranty


  • Flow rates 0-4200 gpm
  • Removes free floating oils and settleable solids
  • Removes 20 micron size hydrocarbons and larger
  • Produces effluent down to 10ppm or less

Meets or Exceeds the following Standards:

  • UL Subject 2215
  • UL 1316
  • U.S. Coast Guard Test Method 46 CFR 162.050
  • API manual on disposal of refinery wastes
  • API bulletin No. 1630, first edition
  • API bulletin No. 421
  • EPA Test Methods 413.1 and 413.2
  • Strokes Law

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