Oil Coalescing Separators (OCS)

The M.W. Watermark™ Oil Coalescing Separator (OCS) is designed to remove free non-emulsified oils, diesel, gasoline and fuels from a waste stream, resulting in an effluent quality of 10 mg/l or less of contaminants 20 microns and larger.

M.W. Watermark Oil Coalescing Separator (OCS-100); Oil Water Separator

M.W. Watermark Oil Coalescing Separator (OCS-100)

The OCS operation is based on closely spaced oleophilic (oil attracting) media that promotes the impact and formation of larger oil particles. As the oil droplets increase in size their rise rate to the water surface also increases.

M.W. Watermark Oil Coalescing Separator (OCS); Oil Water Separator The influent water enters the separator and flows through a tightly stacked bundle of M.W. Watermark media. The media expands the surface area of the separator giving the oil more room on which to combine (coalesce). As the oil droplets accumulate on the media and coalesce they develop into larger droplets that flow up the surface of the media, detach and rise to the water surface. Surface oil decants by gravity into a segregated oil reservoir where it can be removed from the tank. Heavier solids (solids having a specific gravity higher than that of water) will slide down the surface of the media into the sludge chamber at the bottom of the tank for periodic removal. Virtually oil free water travels under an oil reservoir baffle, over an adjustable weir and into a clean water effluent chamber. The water is gravity discharged from this chamber.

Proudly manufactured and assembled in the U.S.A.

Contact M.W. Watermark for details

M.W. Watermark OCS Brochure
OCS Sizing Drawing

Industrial Wastewater Questionnaire

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M.W. Watermark OCS-100. Recently manufactured for the auto industry; Oil Coalescing Separator; Oil Water Separator
M.W. Watermark OCS-100. Manufactured for the auto industry.
M.W. Watermark OCS-150. Manufactured for a canning operation; Oil Coalescing Separator; Oil Water Separator
M.W. Watermark OCS-150. Manufactured for a canning operation.
M.W. Watermark OCS-100 Carbon Steel. Built for a plywood manufacturer; Oil Coalescing Separator; Oil Water Separator
M.W. Watermark OCS-100. Recently built for a plywood manufacturer.
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OCS Product Features

Our systems each come standard with features that improve efficiency and make them easier to use. These include:

  • No moving parts
  • Construction in A-36 carbon, 304 or 316 stainless steel. Welds are dye penetrant tested.
  • Compact design saves floor space
  • Easy cleaning
  • Minimal maintenance
  • Adjustable water weir
  • Integral oil reservoir

OCS Applications

Our Oil Coalescing Separator (OCS) systems can be used across a wide range of industries for a variety of applications, including:

  • Aircraft Wash Racks
  • Airports
  • Automotive
  • Bilge Water Treatment
  • Bus Terminals
  • Chemical Processing
  • DAF/Clarifier Pretreatment
  • Groundwater Remediation
  • Machine Tools
  • Marine Terminals
  • Metal Processing
  • Military Bases
  • Mobile Separation Systems
  • Oil Production and Spill Recovery
  • Parking Lots
  • Petroleum Plants/Refineries
  • Plastics
  • Power Plants
  • Processing Plants
  • Pulp and Paper Mills
  • Railroads
  • R.O. Filter Pre-Treatment
  • Steel Mills
  • Tramp Oil
  • Transportation
  • Trench Water Treatment
  • Utility Companies
  • Vehicle Washes
  • Wash Racks
  • Water Treatment Plants

Available Options

In addition to the standard features, our Oil Coalescing Separator (OCS) can also be equipped with:

  • Control Panels N4X and N7
  • Effluent Pump Package
  • Elevated Design
  • Expanded Effluent Chamber
  • Expanded Oil Chamber
  • Freeze Protection
  • Influent Pump Package
  • Level Switches and Alarms
  • Oil Pump Package
  • pH neutralization
  • Sight Glass
  • Sludge Auger
  • Sludge Pump Package
  • Special Coating Systems
  • Walkways/Platforms/Ladders/

System Design

Inlet Diffusion Chamber
The raw influent enters the OCS through a non-clogging baffle that distributes the flow across the width and depth of the chamber for even distribution. Settleable solids drop out into the sludge chamber before the water enters the M-pack.

Separation Chamber
The separation chamber is filled with an M-Pack oleophilic coalescing media that allows oil drops to collect on the underside of the plates, coalesce, and then rise toward the surface of the water. The M-pack provides a difficult path for the water to pass, continuously changing the direction of flow, which insures coalescence of the oil droplets.

Sludge Chamber
A sludge chamber is located under the separation chamber for capture of heavier particles in the water. The chamber has sloped walls to insure near complete removal of the sludge from the chamber.

Oil Reservoir
The separated oil drops rise and collect atop the separation chamber. As the oil layer increases, oil automatically decants over a fixed weir into an isolated oil reservoir. The reservoir can be expanded to accommodate additional storage needs.

Effluent Chamber
Clean water leaving the M-Pack travels under an oil reservoir baffle, over an adjustable 304 stainless steel weir and into the effluent chamber. The water is gravity discharged from this chamber. The chamber can be expanded to accommodate additional storage needs.

Tank Lids
The separator includes sectionalized lids that completely cover the unit. Inspection hatches can also be provided.

M.W. Watermark OCS-100; Oil Water Separator

OCS Specification Table

Inlet Ø
Outlet Ø
Outlet Ø
Outlet Ø

*Information subject to change without notice, dimensions are approximate, values may vary based on process conditions.

Contact us for more information by calling or filling out our online form.