Analytical Systems International – Oil in Water On-line Analyser

The ability to analytically quantify oil in water is greatly enhanced with the Sample Transfer Stripper (exclusive ASI Membrane Technologies) and the solid state sensor offered by Analytical Systems Keco (ASI). The analyser system utilises patented and exclusive features only available from ASI.

The principle of operation for the Oil in Water Analyzer requires a consistent free flowing liquid sample into the Sample Transfer Stripper unit which separates the VOCs in the oil from the water. A hydrocarbon free, consistently flowing air carrier then sweeps the VOC components to the solid state sensor in the gas phase for quantitative analysis in ppb w, ppm w, or up to saturation levels. An exclusive True Liquid Validation System by PermTube is utilized to verify proper operation of the analyzer with just a flip of a switch. This unattended on-line analysis is economically superior to inaccurate laboratory analyzers where unstable grab samples result in oil deterioration that produce analytical errors. Alternative Oil in Water Monitors utilizing the UV Fluorescence methods tend to suffer from cross-sensitivity with components not intended to be measured, such as debris. This gives false high readings. Furthermore, UV Fluorescence methods generally do not have the ability to measure aliphatic compounds. The 204 measures total hydrocarbons including aliphatic and aromatic compounds. Downtime is reduced to less than 10% of the “El Paso”, Sparger and ‘headspace’ stripping column methods and the economic pay out is increased because of reduced product loss. In one case, 12,000 pounds of product loss per day was quickly identified by this proven and accurate on-line analytical method. Patents and Patents Pending based on letters that are available on request.

Applications include the analysis of oil in water for cooling towers, heat exchangers, holding ponds, run off water, waste water, produced water and more.


• Continuous On-Line Analysis
• No Routine Calibrations Required
• 30+ Years Experience
• Field-Proven Reliability
• Typical 99% Uptime
• Measures Low PPBw, PPMw and up to Saturation
• True Liquid Validation by PermTube
• Measurements include aromatic & aliphatic compounds
• TCEQ “Best Available Control Technology”


• Bilge water discharge monitoring
The International Maritime Organization (IMO) and the U.S. Coast Guard (USCG) requires all ships over 400 gross tons to monitor bilge water discharges and are limited by 15 ppm. The Canadian Coast Guard limits discharge concentration at 5 ppm.

• Oil in Waste water
Where the dissolved oil or hydrocarbon content could be PPBw, PPMw, or at saturation levels, Model 204 Oil in Water Analyzer easily provides continuous measurement online.

• Oil in produced water
The Model 204 Oil in Water Monitor can continuously monitor the discharge of produced water as required by the Environmental Protection Agency (EPA) and other requirements. The EPA requires that produced water discharge must contain a concentration of less than 29 ppm oil and less than 42 ppm grease for a 30 day average and daily maximum.

• Oil in Cooling Water and Holding Ponds
Equipment leaks, spills, and drainage run-offs can cause build-up of hydrocarbon in the water. The Model 204 can give a continuous online indication of the volatile organic carbon (VOC) / oil contained in these waters.

• Fuels in Storm Runoff Water
It is required by the U.S. EPA that all storm water runoff be monitored. The Model 204 can continuously detect fuel in water at a concentration 1 ppm or better, including as dissolved hydrocarbons.

• Phenol in Water
The Model 204 can continuously monitor the cooling water to detect a leak and prevent a discharge violation.

• Hydroelectric dam sumps

• Drain systems for fuel oil storage tank area
Includes hydro-carbon storage facilities.

• Ground water recovery sites
Includes fuel storage and transformer sites.

• Boiler condensate and power plant cooling water reclaiming systems
Including integral oil coolers.

• Intake monitoring for Desalination plants

• Water discharge in municipal water treatment systems
Oily water or grease discharges in excess of 15 parts per million(ppm) is not allowed or surcharged in most municipal water systems.

• Engine cooling water
Engine damage can be caused by oil in engine cooling water.

• Effluent monitoring
After an oil-water separator.