Managing oily wastewater is a challenge almost every facility faces —whether it’s a workshop, manufacturing plant, wash bay, or busy commercial kitchen.Without proper treatment, oil and grease quickly lead to clogged drains, foul odors, equipment damage, and even regulatory penalties. That’s why Oil Water Separators (OWS) have become essential for modern businesses. In this content, we’
ll break down what an oil water separator does, why it matters, and how today’s systems—from industrial OWS units to kitchen grease separators like the MISLIER MsIrOS series—keep operations clean, compliant, and running smoothly.
What Is an Oil Water Separator?
An Oil Water Separator (OWS) is a treatment device engineered to remove oils, grease, and suspended solids from contaminated water before discharge. Industrial OWS units handle petroleum‑based pollutants such as hydraulic oil, diesel, lubricants, machining fluids, and runoff from equipment cleaning.
Most systems function using gravity separation principles and laminar flow. Advanced designs integrate coalescing plates, lamella surfaces, retention‑time control, and staged settlement to accelerate and stabilize separation performance.
What Is the Purpose of an Oil Water Separator?
The purpose of an OWS extends far beyond simply removing oil. In industrial consulting, we classify its value into six major impact zones:
- Environmental Protection – Oil forms films that suffocate aquatic ecosystems.
- Regulatory Compliance – Most regions enforce oil‑content discharge limits between 5–20 mg/L.
- Infrastructure Protection – Oil accelerates corrosion and scaling inside pipelines and pumps.
- Workplace Safety – Oily floors cause slips, fire risks, and harmful vapors.
- Cost Reduction – Cleaner wastewater reduces pump repairs, pipe replacements, and emergency blockages.
- Sustainability Goals – OWS systems support environmental audit readiness.
How an Oil Water Separator Works？
Although OWS designs vary, their engineering logic follows the same sequence:
- Inlet Zone: Wastewater enters and solids settle.
- Primary Settling: Heavy particles drop, reducing turbulence.
- Coalescing Chamber: Angled plate packs merge fine droplets using Stokes’ Law.
- Oil Accumulation: Oil rises and collects at the top.
- Discharge: Clear water exits through a controlled outlet.
This staged flow increases retention time and ensures stable separation even under fluctuating flow conditions.
Two Major Types of Oil Water Separation Systems
Oil‑water separation systems fall into two major categories based on pollutant profile:
- Industrial OWS – For petroleum‑based hydrocarbons.
- Kitchen Grease Separators – For fats, oils, grease (FOG), and organic solids.
These systems are not interchangeable because the chemistry of industrial oil and food‑based grease is fundamentally different.
Industrial Oil Water Separator
Industrial Oil Water Separators are engineered to manage wastewater containing petroleum-based contaminants such as diesel, hydraulic oil, gear lubricants, and coolant residues. These systems typically rely on a combination of gravity settling, controlled flow pathways, and coalescing media to enhance separation efficiency and ensure treated water meets industrial discharge requirements—without referencing any specific model or brand.
Kitchen Grease Separator (FOG System)
Kitchen grease separators—represented by the MISLIER MsIrOS series—handle fats, oils, grease, sauces, and food‑based solids. Challenges include grease solidifying at low temperature, high organic load (COD/BOD), fermentation gases, and sludge buildup. Traditional grease traps fail due to lack of sludge removal and unstable retention time.
MISLIER Grease Separator Types
The MISLIER MsIrOS Series applies advanced European separation standards but is optimized for Asian kitchen wastewater, featuring automated functions, sealed construction, and simplified maintenance.
MsIrOS 025 – Standard Model • Fully sealed PE tank (odor‑proof, corrosion‑resistant)
• Automatic oil discharge
• Manual or electromagnetic sludge removal
• Large overflow chamber
• Optional temperature control
• Compact for small/medium kitchens
MsIrOS 025 PLUS – Intelligent Automatic Model • Automatic sludge discharge pump
• Automatic cleaning and flushing
• Automatic water replenishment
• Dual-level sensors (primary + backup)
• PLC/TFT intelligent control
• Oil-tank full alarm + auto stop
• Optional constant-temperature heating
• Suitable for hotels and central kitchens
Common Applications
Industrial OWS uses: workshops, factories, wash bays, mining sites, power stations. Kitchen grease separator uses: restaurants, hotels, canteens, food plants, bakeries, central kitchens.
Benefits of Oil Water Separation Systems
Modern oil‑water separation systems offer a wide range of operational, environmental, and economic advantages. Beyond basic compliance, they help facilities maintain long‑term stability and reduce hidden risks that often go unnoticed until major problems occur.
- Regulatory Compliance & Risk Reduction — Proper separation ensures wastewater consistently meets discharge limits, reducing the risk of fines, shutdown orders, and environmental violations.
- Protecting Infrastructure & Extending Asset Life — By removing oil and grease early in the process, pumps, pipes, and drainage networks avoid corrosion, scaling, and buildup that shorten service life.
- Lower Operating Costs — Facilities with effective separation systems experience fewer blockages, fewer emergency cleaning events, and reduced need for external waste hauling.
- Improved Workplace Health & Safety — Oil residue can create slippery surfaces, fire hazards, and harmful vapors. A well‑maintained OWS stabilizes working conditions and supports safer operations.
- Odor Control & Better Facility Environment — Preventing oil and grease accumulation reduces fermentation, stagnant water zones, and odor complaints—especially important in food‑service and hospitality environments.
- Support for ESG, Sustainability, and Audits — As more companies adopt sustainability frameworks, OWS systems provide documentable environmental performance that supports ESG scoring, ISO certifications, and internal audits.
- Operational Continuity & Reliability — Stable wastewater treatment protects equipment and prevents unexpected downtime, ensuring smoother production, kitchen operations, or vehicle washing activity.
- Future‑Proofing Against Stricter Regulations — Global wastewater standards continue to tighten. Investing in a proper OWS system prepares facilities for future regulatory requirements without costly retrofits.
Conclusion
Whether your facility handles petroleum oils or kitchen FOG waste, choosing the correct separation system is essential for compliance, maintenance stability, and long-term operational hygiene. MISLIER’s industrial OWS solutions and MsIrOS automatic grease separators offer engineering‑grade performance.
For technical support or engineering consultation, contact us:
Email: leolanmsl.com/harry@lanmsl.com
Phone: +86 19966126255/15221870288
Website: www.mislier.com
FAQ
Q: What’s the difference between OWS and grease separators?
A: Industrial OWS handles petroleum oils; grease separators handle food‑based fats and solids.
Q: Can a facility require both systems?
A: Yes—factories with kitchens often need dual systems.
Q: Do these systems handle emulsified oils?
A: Basic units remove free oils; emulsions require additional treatment.
Q: How often should systems be serviced?A: Intelligent models reduce manual cleaning, but periodic inspections are recommended.