Continuously monitoring dynamic oil concentrations in effluent water, the OIW-100 is a painless and economical option for complying with increasingly stringent wastewater regulations. Measuring aromatics' absorbance across the 250-320nm wavelength range, the OIW-100 accurately correlates total oil concentrations from trace levels to high contamination. The nova-II spectrophotometer is used for aromatics' detection.

In various industries, complying with environmental regulations often boils down to verifying specified limits for oil content in effluent water. In order to validate their investments in wastewater processing, refineries and plants require highly accurate online monitoring of dissolved and un-dissolved hydrocarbon concentrations in runoff water. High oil content in effluent water also presents a maintenance concern, as it often indicates equipment failure (e.g. leaky heat exchangers) and that the wastewater is unfit for reuse in the facility.

By nature, petroleum is a mixture of many compounds; this complex constitution (including hundreds of unique organic compounds) makes it impossible to directly measure the concentration of oil in solution. How can we verify that this vague mixture is below limits in our wastewater?

The answer lies in aromatic hydrocarbons, which, on average, comprise 15% (by weight) of crude oil. These molecules have strong absorbance features in the 250-320nm wavelength range and can thus be easily detected through UV-VIS (ultraviolet-visible) spetrophotometry.

The OIW-100 continuously monitors the total aromatics' concentration in wastewater streams. While conventional analyzers will only measure absorbance at the 254nm benzene peak--a single value susceptible to cross-interference and lacking any internal reference for validation--the OIW-100 uses diode array technology to measure the absorbance spectrum across the full 250-320nm aromatic absorbance range.

The system correlates aromatics' concentration to total oil in the water. To perfect the correlation, the instrument is calibrated for the typical composition of oil in the customer's wastewater (using a process sample).

General Performance

Measurement Technology

nova-II™ UV-VIS diode array spectrometer

Light Source

Pulsed xenon lamp (~5 year lifespan)

Sample/Analyzer Interface

Flow cell (various materials and path lengths available)

Sample Conditioning

Extractive system designed to create an oil-free background sample for zeroing. Process sample is routed through a device which effectively removes all oil using a special filtration clay; the resultant oil-free sample is transported to the background vessel, which acts as a reservoir of oil-free background sample. The auto-zero procedure automatically uses liquid from this vessel for 60-second background adjustment task. Unfiltered process sample is simultaneously fed into the flow cell for measurement of oil concentration.

Accuracy

**Custom measurement ranges available; typical ranges specified below.

Total Hydrocarbons
0-20 mg/L range: ±0.2% full scale

Response Time (T10 - T90)

10s

Zero Drift

±0.1% after 1hr warm-up, measured over 24hrs (constant ambient temp.)

Sensitivity

±0.1% full scale

Noise

0.004 AU at 220nm

Calibration

Factory calibrated with customer sample

Verification

Easy verification/validation with standard certified gas samples and neutral density filters
Operating Conditions

Ambient Temperature

0 to 55 °C (32 to 131 °F)
[Optional upgrade: -20 to 55 °C (-4 to 131 °F)]

Sample Temperature

-20 to 150 °C (-4 to 302 °F)

Sample Pressure

206 bar (3000 psi)

Analyzer Environment

Indoor/outdoor (no shelter required)
Hardware

Size

Analyzer enclosure (standard): 24" H x 20" W x 8" D (610mm H x 508mm W x 203mm D)
Sample conditioning system enclosure (standard): 24" H x 30" W x 8" D (610mm H x 760mm W x 200mm D)

Weight

Analyzer (standard): 32 lbs. (15 kg)

Wetted Materials

Analyzer (standard): stainless steel 316/316L; K7 glass; Viton
Sample conditioning system (standard): stainless steel 316/317; quartz; Viton

Outputs

one galvanically isolated 4-20mA output per component; modbus TCP/IP (optional); RS232 (optional); Fieldbus, Profibus, and HART (all optional); two digital outputs for fault and sampling system control (user programmable)

Electrical Requirements

85 to 264 VAC 47 to 63 Hz

Power Consumption

45 watts

Area Classification

General Purpose (standard) / Class I, Div. 2 (optional) / Class I, Div. 1 (optional) / ATEX Exp II 2(2) GD (optional)

The OIW-100 Sample Conditioning System

The main purpose of the OIW-100 sample conditioning system is to create an oil-free background sample for zeroing.

For example, the system displayed here is designed for measuring oil in pond water; since pond water can vary significantly and somewhat mysteriously in composition, a continuous sample with all oil removed is required for blanking the instrument. Only certain deviations from this volatile background spectrum are registered as the presence of oil by the analyzer.

The sample is routed through a device which effectively removes all oil using a special filtration clay. This oil-free sample is transported to the background vessel which acts as a reservoir of oil-free pond water. The auto zero procedure automatically uses liquid from this vessel for background adjustment (a 60 second task).

At the same time, an untreated pond water sample is constantly being fed into the flow cell for direct measurement of oil concentration.

For your convenience, we offer two types of quotations. Based on the current completeness of your project information, please select from the RFQ options below:
Quick Quote
  • Provides budgetary quote only (non-binding)
  • Requires only basic contact information and a measurement description
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Firm Quote
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