The HORIBA OCMA-500 is a benchtop oil content analyzer that measures the concentration of oil in water automatically. Inject the water sample and solvent, press start, and the instrument carries out extraction, measurement and draining on its own — there are no drainage valves to open and close and no evaporation step to supervise. It replaces the earlier OCMA-310.

Measurement uses solvent extraction followed by non-dispersive infrared (NDIR) absorption. Because the solvent is never evaporated, light oils such as gasoline and toluene are not lost during analysis — a well-known source of error in n-hexane gravimetric methods, which drive off low-boiling-point fractions before the oil can be weighed. Results are read directly as oil concentration, with no weighing and no gravimetric calculation.

Key features

• Fully automatic cycle: extraction, measurement and drainage at one button press
• Solvent extraction with NDIR detection — retains volatile and low-boiling-point oils
• Complies with ASTM D7066
• Uses S-316 extraction solvent, which is not regulated under the Montreal Protocol
• Consumes 20% less solvent than the previous generation, lowering running costs
• Operates on 8 mL of solvent with 16 mL of measurement liquid, or 10 mL with 20 mL
• Color graphic LCD and backlit extraction tank so you can see conditions inside the tank

Part number 3200555915.

OCMA-500 or OCMA-550?

The OCMA-500 performs the extraction internally and automatically — the right choice for routine oil-in-water testing on liquid samples, where you want to hand the instrument a water sample and walk away. The OCMA-550 expects samples that have already been extracted externally, and suits residual oil on components and oil adhering to solids such as soil.

Applications

• Oil and grease compliance monitoring in industrial and factory wastewater
• Effluent discharge permit testing and pretreatment program monitoring
• Produced water and oilfield wastewater analysis
• Ballast water and bilge water monitoring on ships and in ports
• Refinery, petrochemical and metalworking plant process water
• Car wash, food processing and machining coolant wastewater
• Environmental water and marine oil content measurement
• Groundwater and remediation site monitoring for hydrocarbon contamination

Consumables and running costs

Budget for S-316 extraction solvent as an ongoing consumable. The SR-305 solvent reclaimer recovers and reuses spent S-316 and pays for itself quickly at moderate sample throughput. B-heavy oil (specific gravity 0.895 at 20 °C) is used to prepare span calibration liquid, and tridecane is also available for span solution preparation. Teflon filter elements, filter packings, the quartz crystal sample cell and cell cap are all stocked — see the Horiba Parts & Accessories collection.

Documentation

• OCMA-500/550 brochure and specifications (PDF)
• OCMA-500 instruction manual (PDF)
• OCMA-500 product page at HORIBA

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