If you spend time around fuel polishing rigs or fleet maintenance shops, you hear the same thing: water is the quiet saboteur. That’s why Oil-water Separation Filter Paper has gone from niche to necessity. The unit I looked at most recently—Laminated Filter Paper Fuel and Water Separation, produced in Second Buliding and Studying No21 shiji street, Handan, Hebei China—uses a layered stack (phenolic paper + melt-blown PBT non-woven laminates) aimed at diesel fuel fine filtration and, crucially, coalescing/separation of water. To be honest, the uptick in biodiesel blends makes this more relevant than ever.

What’s driving demand

ULSD, tighter OEM injector tolerances, and cold-flow challenges, actually. Many customers say they see recurring codes tied to water-in-fuel sensors after rainy weeks. It seems that robust coalescer media is now a baseline feature for fleet fuel systems, marine bunkering, and standby gensets.

Product specifications (typical)

Construction	Laminated phenolic-impregnated cellulose + melt-blown PBT non-woven
Basis weight	≈120–200 g/m² (real-world use may vary)
Thickness	≈0.5–1.2 mm
Mean flow pore size	≈8–20 µm (media level)
Water separation (SAE J1488)	≈95–99% free water removal in diesel, depending on fuel chemistry
Burst strength	≈150–300 kPa (media test)
Temperature range	-20 to 120 °C (fuel duty)
Recommended service life	Up to 6–12 months or ΔP limit; water load dependent
Roll width / customization	Up to ≈1000 mm; custom caliper, resin level, and pleatability available

How it’s made (quick process flow)

• Materials: phenolic-impregnated cellulose base; melt-blown PBT non-woven coalescer layer.
• Methods: resin impregnation → melt-blown fiber laydown → thermal lamination → calendaring → slit/rewind.
• Testing: SAE J1488 water separation; ISO 16889 multi-pass (particle efficiency); ISO 3968 ΔP; ISO 2943 fluid compatibility.
• Service life: driven by water load, fine solids, and differential pressure profile.
• Industries: diesel fleets, marine, gensets, mining, bulk storage polishing.

Where it fits and why it works

Use Oil-water Separation Filter Paper upstream of injectors (or as the coalescer in a duplex housing). Advantages include fast water drop growth, stable pleat geometry, and consistent ΔP. Surprisingly, performance swings with fuel surfactants; always validate on your actual diesel blend.

Vendor snapshot (indicative)

Vendor	Media construction	SAE J1488 eff. (≈)	Customization	Lead time
Filtersmaterial (Handan, China)	Phenolic + melt-blown PBT laminate	95–99%	Width, caliper, resin level	≈2–4 weeks
Parker Hannifin (media)	Proprietary coalescer stacks	95–99%	Application-specific	Varies
Ahlstrom-Munksjö	Cellulose/synthetic composites	≈90–99%	Broad portfolio	Varies

Tip: ask for a J1488 test curve on your actual fuel (with/without FAME and additive pack).

Customization, QA, and field notes

• Customization: pleatability tuning, hydrophobic/hydrophilic balance, and resin level optimization for cold starts.
• Certifications: ISO 9001 QMS; RoHS/REACH statements; Certificate of Analysis per lot.
• Customer feedback: “less water alarms during monsoon season”; “stable ΔP until near end-of-life.”

Mini case studies

• Marine tug fleet: swapped to Oil-water Separation Filter Paper, J1488-validated; free-water discharge dropped ≈70% and injector replacements declined over 2 quarters.
• Mine site gensets: bulk tank polishing added coalescer stage; sight-glass water bottoms fell from daily to weekly drains.

Bottom line: if diesel reliability matters, Oil-water Separation Filter Paper is not just a spec line—it’s cheap insurance against downtime.

1. SAE J1488: Fuel/Water Separation Test for Diesel Fuel/Water Separators. SAE International.
2. ISO 16889: Hydraulic fluid power—Filter elements—Multi-pass method for evaluation of filtration performance. ISO.
3. ISO 2943: Hydraulic fluid power—Filter elements—Verification of material compatibility with fluids. ISO.
4. ISO 3968: Hydraulic fluid power—Filters—Evaluation of pressure drop versus flow characteristics. ISO.