Oil in Water Monitor and Hydrocarbon Analyser: MS1200

The MS1200 is an on-line oil in water monitoring system which provides low level measurements of hydrocarbon, oil and VOC concentrations in water. Some applications include:

  • Monitor water abstraction points such as raw river water, boreholes and reservoir water
  • Monitoring for oil in water contamination
  • Detect VOC contamination in wastewater
  • Monitor drain and stormwater systems for flammable liquids
  • Surface water systems for fuel pollution
  • Offer a monitoring solution for air, land remediation and industrial applications
  • Detect VOC breakthrough in carbon beds
  • RO membrane protection
  • Measurement of VOCs in process water


Key Benefits

  • No sensor contact with water: low maintenance, no sensor cleaning
  • No reagents: low running costs
  • Electronic Nose: not affected by turbidity
  • High sensitivity: ideal for potable water
  • Can be calibrated for specific substances: used to monitor known spills
  • Catches VOC chemical spills not just hydrocarbons
  • Alarms to SCADA and other communication interfaces

An Hydrocarbon Analyser to detect oil spills

Oils and hydrocarbons in general are, very often, the main components of a wide range of products, going from fuels to solvents to many of the chemicals used in the industry during their treatment processes.

In industrial production it is possible that some of these hydrocarbons, oils and solvents leak into drains, or worse, directly into the environment.

Similarly domestic and agricultural fuel storage can result in accidental spills into water coursesand aquifers .

This can be a real and huge problem for water supplies and, in the worst case, threaten the water security of whole communities. Often, these accidents result into huge fines and expensive cleaning-up operations.

An Oil in Water Analyser can make a difference, by giving an early warning when a problem arises.

Oil In Water vs Oil On Water

Oil IN Water Analyser (MS1200)

An “Oil IN Water” analyser , such as the MS1200, measures very low concentrations of hydrocarbons dissolved in the water; this is what we are usually interested to know as it provides the first indication that an oil spill or fuel spill has occurred.

The operating range of the MS1200 Oil in Water Analyser is 0 – 3000 ppb, but most applications focus on the 0 – 200 ppb range: As the manager of a drinking water plant , you want your oil in water analyzer to give you a low level alarm at around 20 ppb and a high level alarm at 50 – 100 ppb.

This means that, in most cases our MS1200, is used for applications where the operator of the WTP has carried out a risk analysis and has decided to protect their water intakes from low level contamination of oil in water or where there has been known to have been a fuel spill and monitoring of the aquifer is necessary.

Moreover the MS1200 oil in Water Analyser will detect any hydrocarbon, both aliphatic (chains) and aromatic (rings). This means that, compared with other technologies, it can see a wider range of hydrocarbons at very low concentrations.

Oil ON Water Analysers (Other Technologies)

Oil on Water Monitors or analysers are different in principle as they are designed to detect a floating film of oil or fuel on top of a body of water. By definition this means that they detect hydrocarbons at a much higher concentration than an Oi in Water Analyser.

The system usually work by using a laser positioned above the water and a detector which measure the reflected laser beam. The presence of a floating film will disperse the reflected laser beam and this loss can be measured. This technology is usually cheaper than an e-nose based system and it’s usable when the application is to measure high concentrations.

On the other hand there are some limitations:

  1. It IS affected by disturbance of the water surface : since it’s an optical measurement, the reflected laser will be disturbed by the rough water surface
  2. It cannot measure low concentrations
  3. It cannot detect hydrocarbons which are readily dissolved in the water as these will not form a film

Oil on Water Detectors are usually used to detect gross leakage from oil and fuel storage sites.

Principle of Operation

MS1200 utilises a contactless measurement technique based on Henry’s Law, sensing headspace gases or volatiles in the sampling tank provided, and provides a measurement system with very low maintenance requirements.

Thanks to the clever design and technology the sensor never touches the water. This results in reduced drift, virtually no fouling, no sensor cleaning and very low maintenance.

The MS1200 is accurate to low ppb concentrations and its wide dynamic range allows it to be used in a wide variety of environments.

The concentration of Volatile Organic Compounds and Water Vapour in the headspace increases until equilibrium is reached with the concentration in the water (Fig. 1)

A sample of gas is then taken from the headspace and the response analysed to provide a concentration in ppb of contaminants in the water (Fig. 2).



Technical Details

Spec Value
Range* 0 – 3000 ppb in water
Accuracy** +/-10%
Repeatability +/-2%
Sampling Frequency 5 – 20 Minutes
User Interface 8″ resistive touchscreen (optional)
Data Storage µSD Card and Internal Memory
Data Interface 4 – 20 mA, Profibus, Modbus, Wireless, USB
Alarms x2 Via Relay Drivers, Levels User Definable
Operating Temperature Range 0 °C– 40 °C (contact us for wider temperature range)
Water Temperature Range 1 °C– 40 °C
Power Consumption 10 W Continuous (90-240 VAC or 24 VDC)
ATEX Zone 2 (Optional)
Reagents None
Carrier Gas None
Consumables GAC filter media, Air Filter every 6 months
Validation Every 6 Months
*Other ranges available. Please contact Multisensor Systems.
**200 ppb toluene in water, 25 °C