Multi-stage oil separation systems for petroleum refineries achieving <15 mg/L O&G discharge compliance through API separators, DAF flotation, and coalescing media.
Treat drilling muds, cuttings wash water and site runoff. Solid-liquid separation and water recycling for drilling operations.
Refinery wastewater treatment including API separators, DAF, advanced biological treatment and polishing for strict discharge.
Oil and gas wastewater treatment for produced water treatment.
Sour water and desalter effluent treatment for petroleum refineries.
Removing Oil from Complex Refinery Streams
Petroleum refineries generate wastewater containing free oil, emulsified oil, and dissolved hydrocarbons from crude processing, product handling, and equipment drainage. Effective oil separation is the critical first step in refinery wastewater treatment, protecting downstream biological processes and ensuring compliance with stringent O&G discharge limits. API separators, corrugated-plate interceptors and dissolved-air flotation are staged to remove free, then emulsified, then residual oil ahead of biology. Reynolds & Bauhm size each stage to the refinery’s flow so downstream processes are protected and oil-and-grease limits are met.
Gravity-based API separators remove free oil droplets >150 micron, recovering saleable hydrocarbons with minimal operating requirement.
DAF systems with chemical conditioning break emulsions and remove fine oil droplets down to 10-20 micron.
Coalescing plate separators and multimedia filters provide final polishing to achieve <5 mg/L O&G for water reuse applications.
Recovered oil can be recycled back to the refinery process, turning a waste stream into a valuable resource.
Refinery Oil Separation Sources
Treatment of oily wastewater from crude and product storage areas, process units, and equipment drainage systems.
High-salinity wastewater from crude oil desalting containing free oil, solids, and dissolved salts requiring specialised separation.
Handling and reprocessing of API separator sludge and bottom solids with concentrated oil content.
High-solids wastewater from tank cleaning and bottoms removal with concentrated oil and sludge content.
Treatment of atmospheric and vacuum distillation unit drainage containing free and emulsified crude oil.
Treatment of blowdown and drainage from cooling towers, boilers, and utility systems throughout the refinery.
Integrated Oil Separation Train
Equalization tanks balance flow and oil loading to prevent shock loads on separation equipment.
API separators use gravity to remove free oil and settleable solids from wastewater streams.
DAF systems remove emulsified oil and fine suspended solids through microbubble flotation.
LAMELLA separators provide high-rate settling of oil-floc complexes and precipitated solids.
Self-cleaning filters and coalescing media remove residual oil before discharge or reuse.
Products for Refinery Oil Separation
High-efficiency oil and solids removal through microbubble flotation for refinery wastewater.
Benefit: 95%+ oil removal
Gravity oil-water separation for free oil removal upstream of secondary treatment processes.
Benefit: Low operating requirement
High-rate solids separation for primary and tertiary clarification in minimal space.
Benefit: 70% smaller footprint
Automatic backwash filtration for final oil polishing and protection of downstream equipment.
Benefit: Continuous operation
Flow balancing and oil surge protection to maintain consistent separator performance.
Benefit: Shock load protection
Screw presses and centrifuges for refinery sludge dewatering to minimise disposal requirements.
Benefit: 60-80% efficiency improvement
Why Choose Reynolds & Bauhm
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View PageRefinery wastewater treatment including API separators, DAF, advanced biological treatment and polishing for strict discharge.
View PageFrom bulk API separators to polishing IGF / DAF — the layered approach to oil removal.
Rectangular gravity separator to API-421. Sized for Stokes-Law rise of 150 μm oil droplets. Surface loading 0.4–0.8 m/h. Inlet <1,000 mg/L oil → outlet <100 mg/L.
Corrugated plate or tilted-plate separators — high-rate stacked plates create thin laminar layers, settling droplets in centimetres. Surface loading 1.5–3.0 m/h.
Mechanical impeller draws atmospheric or process gas; bubbles attach to oil droplets and lift to surface. Outlet 10–30 mg/L oil. Robust for high-TDS produced/desalter water.
Pressurised water saturated with air at 4–6 bar; release to atmospheric tank creates fine bubbles. Outlet <10 mg/L oil with coagulant aid.
Downflow filter at 25–35 m/h with walnut-shell media. Removes residual oil and TSS to <5 mg/L. Backwash uses produced water.
UF/MF or organophilic NF for <1 mg/L oil and TSS targets — the route to reuse-quality water. Capital expenditure higher but enables process integration.
Stokes’-law sizing, API Publication 421 design methodology, rectangular API / CPI / TPI configurations and refinery-train integration.
Sizing, components, types, materials, codes & compliance — the full engineering reference for gravity oil-water separation.
Read the API Separators PageCompare the three dominant configurations side-by-side — droplet cut-size, footprint, Operating expenditure and best-fit applications.
Compare Separator TypesCFD-verified F-factor for shorter basins, optimised inlet diffusers and reduced civils Capital expenditure.
CFD EngineeringContact our experts to design an oil separation train tailored to your refinery.
Our expertise spans multiple industries with sector-specific water treatment solutions.