Oil in Water Monitor

Hydrocarbons, PAHs and Pollution Analyser.

High Reliability, High Sensitivity, High Precision

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MS1200 Touchscreen Version

The MS1200 is an on-line Oil in Water monitoring system which provides low level measurements of Hydrocarbon,
Oil and VOCs concentrations in water. 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

Features and Benefits

  • No sensor contact with water: low maintenance, no sensor cleaning
  • No reagents: low running costs
  • Measures both Polycyclic Aromatic Hydrocarbons (PAHs) and VOCs
  • 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

For more information on the principle of operation, click on the FAQs tab.

In this video Dr. Andrew McInnes gives a quick introduction of the system's operation.

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 courses and 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 the difference, by giving an early warning when a problem arises.

Oil In Water vs Oil On Water

Oil In Water Analyser (MS1200)

Hydrocarbons An “Oil In Water” monitor , 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 monitor 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 In Water Analysers (Other Technologies)

Oil in 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.

Spec Value
Range* 0 – 3000 ppb in water
Accuracy** +/-10%
Repeatability +/-2%
Sampling Frequency Continuous Mode / 20 Minutes Mode
User Interface 8" resistive touchscreen (optional)
Data Storage µSD Card and Internal Memory
Data Interface 4 – 20 mA and USB (Standard); Profibus, Modbus, Wireless (Optional)
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 Standard Version: 10 W Continuous (90-240 VAC or 24 VDC)
Touchscreen Version: 20 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
Title Type Format
MS1200-SYS Oil in Water VOC Monitor Datasheet PDF
Water Intake Protection System Study PDF
MS1200-SYS Installation (Contact Us) Manual PDF
MS1200-SYS Operation (Contact Us) Manual PDF
Lac Mégantic disaster increases awareness of water treatment plant vulnerability Case Study (Long) PDF
Monitoring of River Water Intake for Petroleum Contaminants Case Study PDF
Monitoring of Reservoir Feed for Hydrocarbon Contamination Case Study PDF
Protecting RO Membranes at a Pet Food Manufacturer Case Study PDF
Monitoring of a borehole to detect potential fuel contamination Case Study PDF
VOC detection in Industrial Estate, UK Case Study PDF
Monitoring a High Iron and Manganese Content Borehole for Hydrocarbons Case Study PDF
Spill detection system at engine manufacturing plant Case Study PDF
Monitoring VOCs in Wastewater in an ATEX 2 Environment Case Study PDF
Monitoring for VOCs in Panama Canal Case Study PDF
Monitoring for VOCs in water reclaimed from a petrochemical plant Case Study PDF
VOC Analyser protects WTP inlet Case Study PDF
Monitoring of spring water for VOC contamination Case Study PDF
How does the MS1200 Oil in Water Analyser work?

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).

What does the MS1200 Oil in Water Analyser actually measure?
The MS1200 measures a wide range of hydrocarbons including most PAHs, aromatic and aliphatic hydrocarbons. It is conceived to be a generic early warning system and, for this reason, it has been designed to respond to as many contaminants as possible. A detailed study can be found here. If you are interested in a specific compound or sets of compounds, please get in touch
What is the difference between an Oil in Water, PAHs, Hydrocarbon, VOC Analyser?
Different people in different sectors refer to the same problem using different expressions. In the water industry the operators usually talk about “Oil in Water Analyser” , “Pollution Event Analyser” or “PAHs Analyser”; in the industrial sector customers refer to “VOC Analyser” or “Hydrocarbon Analyser”. Most of the times these expression refer to applications that can be approached using the MS1200.
What is the reported value?
The instrument will report the Total VOC value that the sensor detects as an equivalent of Toluene at 25 C.
Does the MS1200 measure kerosene, diesel, gasoline and other fuels?
Yes. The instrument detects these and many other compounds. For more information on a specific compound, contact us.
How is the MS1200 calibrated?
The instrument is factory calibrated using Toluene standards. Toluene has been chosen since it is relatively safe to use and to store and because it is representative of BTEX (benzene, toluene, ethylbenzene and xylene), a compound of interest in the water sector as well as in the industrial sector.
What is the required maintenance? Is it expensive?
The instrument requires a service every 6 months to replace some low cost components such as activated carbon filters and to make sure that there are no air leaks.
Do I need a filter before the instrument?
In most applications a filter is not needed. The sampling system (the tank) is designed to deal with river water to reduce blockages.
If you are concerned about blockages, or your water has very high levels of suspended solids, please get in touch.
What is the warranty?
Every instrument comes with 1 year warranty from the shipment date
What is the expected life of the sensor? Is it difficult to replace?
The sensors used in the Oil in Water and Hydrocarbon Analyser are designed to last a long time. On average sensors are replaced every 5 years, however this time can change depending on the conditions of the water and the VOCs levels they are exposed to. The sensor is easy to replace
Is the instrument certified?
There is not an EPA certified method for the on-line detection of oil in water and pollution, this means that a certification is not possible. Some local institutions have suggested to certify the process and we have carried out trials verified by national institutions against GCMS analysis in strict conditions. You can find more information in this document.
Can the MS1200 be used in hazardous environments?
The MS1200 is available for use in ATEX Zone 2 environments. It is not suitable for use in Zone 0 or Zone 1 applications.
How often does the MS1200 take a measurement?
A measurement is taken every second. However, the user can also set the instrument to take a measurement every 5, 10 15 or 20 minutes if it is required to conserve power or if trending data only is required.
What are the advantages of using e-nose technology?

E-nose technology allows for non-contact measurement meaning that:

  • fouling of the sampling system is minimized through large diameter tubes being used
  • suspended solids and dissolved chemical compounds do not coat or damage the sensors or optical components as used in Ultra Violet, Infra Red or Laser spectroscopy systems, extending their lifetime and reducing cleaning requirements
  • no reagents are necessary as for instruments which use colorimetry as there detection technology
  • no purging gases are needed as for GCMS based systems
Which regions of the world use Multisensor’s products?
Multisensor’s products are used throughout the world, including Europe, North, South and Central America, Asia including China, South Korea, Taiwan and Singapore. Multisensor has more than 50 distributors globally.

Case Studies

The MS1200 Oil in Water and Hydrocarbon Analyser has been used in a wide number of applications, here are some.

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