HACH OWF-100 Online Oil-in-Water Analyzer

Overview

The HACH OWF-100 Online Oil-in-Water Analyzer is an industrial-grade, continuous monitoring instrument engineered for real-time quantification of hydrocarbon contamination in aqueous streams using ultraviolet (UV) fluorescence spectroscopy. It operates on the fundamental photophysical principle that aromatic compounds—common constituents of mineral oils, diesel, lubricants, and crude oil—absorb UV radiation (typically 254 nm or 280 nm excitation) and emit characteristic fluorescence in the visible range (e.g., 320–420 nm). The intensity of this emitted signal exhibits a linear relationship with oil concentration over defined dynamic ranges (0–2.0 mg/L and 0–10 mg/L), enabling direct, calibration-based quantification without chemical derivatization or solvent extraction. Designed for integration into municipal wastewater treatment plants, industrial cooling water circuits, produced water handling systems, and refinery effluent monitoring points, the OWF-100 delivers robust performance under variable hydraulic and thermal conditions while maintaining compliance with regulatory expectations for continuous emission monitoring (CEM) and process safety integrity.

Key Features

• Reagent-free, non-contact measurement architecture eliminates consumables, waste generation, and cross-contamination risk—fully aligned with ISO 14001 environmental management system requirements.
• Windowless full-flow optical cell design removes susceptibility to fouling, scaling, or biofilm accumulation on optical surfaces—a common failure mode in conventional UV-Vis analyzers with quartz windows.
• No mechanical actuators, peristaltic pumps, or solenoid valves; solid-state construction ensures high MTBF (>12,000 hours) and minimal scheduled maintenance intervals.
• Rapid response kinetics (T90 ≤ 3 minutes) supports timely detection of oil breakthrough events in separator outfalls or membrane filtration bypass scenarios.
• Integrated temperature and pressure compensation algorithms correct for density and fluorescence quantum yield variations across operational sample conditions (0–30 °C, 0.02–0.3 MPa).
• IP54-rated enclosure (indoor installation only) with corrosion-resistant aluminum chassis and EMI-shielded electronics suitable for industrial control room or analyzer shelter deployment.

Sample Compatibility & Compliance

The OWF-100 is validated for use with freshwater, seawater (with optional salinity compensation), treated wastewater, and low-salinity produced water matrices. It demonstrates minimal interference from turbidity (<100 NTU), suspended solids (<50 mg/L), and common surfactants at typical process concentrations. While not certified to specific EPA Method 1664 or ISO 9377-2 equivalence, its measurement traceability follows NIST-traceable UV source calibration protocols. Data integrity meets GLP and GMP-aligned documentation standards, supporting audit readiness for facilities subject to ISO/IEC 17025 accreditation or regulatory reporting under EU Water Framework Directive (WFD) Annex VIII or US Clean Water Act NPDES permit conditions.

Software & Data Management

Local configuration and diagnostics are performed via a built-in 4.3-inch resistive touchscreen interface compliant with IEC 61000-4-2 ESD immunity. The embedded firmware supports Modbus RTU (RS-485) and optional Modbus TCP/IP for integration into SCADA, DCS, or cloud-based IIoT platforms. All calibration events, zero/span checks, fault logs, and analog output history are timestamped and stored onboard for ≥30 days. Audit trail functionality records operator ID (via password-protected access levels), action type, and parameter changes—consistent with FDA 21 CFR Part 11 requirements when deployed in pharmaceutical or food-grade water applications.

Applications

• Monitoring oil content in secondary clarifier effluent prior to disinfection or discharge.
• Real-time tracking of hydrocarbon carryover in steam condensate return lines within power generation facilities.
• Leak detection in heat exchanger cooling water loops serving petrochemical process units.
• Compliance verification for offshore platform produced water reinjection limits (e.g., OSPAR Commission Decision 2000/3).
• Early warning of fuel oil ingress in drinking water distribution network source intakes.

FAQ

Does the OWF-100 require periodic lamp replacement?

Yes—the UV LED excitation source has a rated lifetime of ≥10,000 hours; replacement is recommended annually during routine preventive maintenance.
Can it measure emulsified oil fractions?

It detects fluorescent aromatic hydrocarbons regardless of physical dispersion state; however, non-aromatic saturates (e.g., paraffinic base oils) exhibit negligible fluorescence and may be underreported.
Is field calibration possible without lab reference standards?

Zero calibration can be performed with clean deionized water; span calibration requires certified mineral oil standard solutions traceable to NIST SRM 2781 or equivalent.
What communication protocols does it support out-of-the-box?

Standard RS-485 Modbus RTU; Ethernet-based Modbus TCP and HART 7 options are available as factory-configurable upgrades.
How is foam rejection achieved mechanically?

A patented flow-path geometry induces controlled laminar shear and surface tension disruption upstream of the measurement zone, preventing foam accumulation in the optical path without air elimination hardware.