Why this matters: Manufacturers want consistent re-refined base oil quality (stable VI, low sulfur, clear color) without supply risk. Thin Film Distillation (TFD)—also called wiped film evaporation (WFE)—has emerged as the benchmark route to transform used lubricating oil (ULO) into saleable SN grades for blending.
What Thin Film Distillation Does Better
Compared with conventional re-refining, TFD/WFE creates a very short residence time and a highly turbulent, uniform film under deep vacuum. This minimizes thermal cracking while stripping contaminants and heavy ends, enabling:
- Higher purity & better color (clear/bright visual, strong oxidative stability)
- Lower sulfur & TAN, helping with additive response and long-drain oils
- Tighter viscosity targets (e.g., SN cuts for SN 150 and SN 500)
- Lower odor & volatiles, beneficial for sensitive uses (food-grade packaging wax blends, cosmetic intermediates)
Process Flow (From Waste Oil to Finished Base Oil)
- Pre-treatment & Dehydration
Filtration, demetallization, and water removal protect the unit and stabilize feed variability. - Vacuum Distillation (Primary Cut)
Removes light ends and gases; pulls lube-range fractions for further polishing. - Thin Film/Wiped Film Evaporation (TFD Core Step)
Under high vacuum, a wiper spreads the feed into a thin film on heated surfaces. The distillate becomes the base oil fraction, while heavy residues (asphaltenes, carbonaceous materials, additives’ ash) exit separately. - Hydrotreating / Hydrofinishing
Hydrogenation improves color, sulfur, nitrogen, and stability to approach Group I/II-like quality, depending on severity. - Clay/Polishing Filtration & Final Blending
Final clarity, oxidation stability, and pour point are trimmed before packaging.
Result: a clear, low-impurity, stable re-refined base oil that performs competitively versus virgin Group I for many formulations.
Where TFD Re-Refined Base Oils Fit
- Automotive & Industrial Lubricants: Engine oils, hydraulic fluids, circulatory oils, metalworking fluids—where consistent KV @40°C, VI, and flash point matter.
- Grease Manufacturing: Reliable base stocks for calcium, lithium, and complex greases, with predictable thickener response.
- Rubber & Plastic: As a process oil component where low sulfur and color are valued.
- Candles & Cosmetics: When the formulation demands low odor, clean color, and tight volatility.
- Chemical & Process Industries: Carrier fluids where low contaminants reduce side reactions.
Buying Checklist for Operations & Procurement
- Spec Sheet Discipline: Request full specs (KV@40/100, VI, color, sulfur/ppm, TAN, pour/flash, Noack). Expect ranges due to feed variability—but insist on control limits.
- Unit Capability: Confirm the supplier operates true thin film/wiped film plus hydrofinishing (not only atmospheric/vacuum cuts).
- Consistency Proof: Ask for batch COAs, retention samples, and ISO-aligned QC.
- Sustainability: Re-refining supports circular economy goals and reduces Scope 3 compared with burning or disposal of ULO.
- Logistics & Lead Time: Ensure packaging (flexitanks/IBC/drums/bulk) and export paperwork align with your lanes.
Explore Products & Specifications
- See our SN 150 Base Oil page for technical details and supply options. (workandenergy.com)
- Compare with SN 500 Base Oil and SN 600 Base Oil for heavier cuts. (workandenergy.com)
- Browse the complete Base Oil portfolio. (workandenergy.com)
If you’re qualifying re-refined base oil from a TFD/WFE unit for lubricants, grease, or rubber compounding, message us for current specs, pricing, and export delivery windows.
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