CoMic™ is designed to detect nanoscale aggregates of surfactant molecules, which are formed by film-forming corrosion inhibitors above a certain concentration, the Critical Micelle Concentration (CMC). These aggregates are called micelles.

CoMic™ works by detecting corrosion inhibitor micelles in the system. Therefore, the corrosion inhibitor being used needs to be micelle forming. Typically, CoMic™ is suitable for water-soluble, surfactant type corrosion inhibitors i.e. those containing quaternary amines, imidazolines and/or phosphate esters. We have found that the vast majority of such oilfield corrosion inhibitors are micelle forming and suitable, nevertheless.

It is recommended that corrosion inhibitors are tested using our Concentration Series Kit, prior to field deployment, to ensure that best results are achieved.</p>

CoMic™ is a unique tool that provides data unavailable from any other method. It works in a complementary manner to your coupon, probe data and other monitoring techniques to enhance your system data set, enabling a complete system review to be carried out. The CoMic™ technique is unique and can provide additional information on pump efficiency, optimal dosage and impact of system changes.

This powerful data allows you to make informed decisions to enhance your long term asset integrity.

Yes, it is acceptable to have some oil present, and the water cut can be low. For example, CoMic&trade has successfully tested 1-2% water cut on many occasions. However, water must be present as CoMic™ can only be used for oilfield fluids that contain free water. CoMic™is an optical method so light needs to be able to pass through the sample. Where samples are significantly opaque a clean-up step can be introduced such as a short settling time, heating or centrifuging samples.

Samples should not be filtered as this leads to corrosion inhibitor loss.

CoMic™ detects micelles in the water phase and so it depends on the level of partitioning. If the asset has water in the system that it wishes to ensure is protected with corrosion inhibitor then it is anticipated that the chemical will have been chosen to allow some partitioning to the aqueous phase. In this case, CoMic™ will be applicable. Thus, some systems may have lowerwater cut, with turbulent flow and choose to use an oil-soluble chemical. Yet there may be points in the system where fluid is known to stratify and water drop out. In this case, it will be desirable that this water is protected with corrosion inhibitor and CoMic™ can be used to ensure it is dosed to give optimal protection.

Corrosion inhibitor should be checked for partitioning prior to field deployment by using our Concentration Series Kit. This is key to understanding how the chemical behaves whether CoMic will be appropriate for the field in question. Please get in touch if you wish to learn more about this.

CoMic™ can detect corrosion inhibitors in the presence of most production chemicals. Where the other production chemicals are surfactants, such as some demulsifiers, then these may also form micelles. Whether or not CoMic can be used will depend on the partitioning of these other surfactants. Often we will screen the other production chemicals being used in a system prior to using CoMic™ on-site to ensure there will be no interference. High levels of methanol (>20%) and monoethylene glycol (>50%) in samples will cause interference with CoMic™.

False positives have also been observed with some polymer species. Please contact us to find out more.

This depends on when micelles form in the system i.e. what is the critical micelle concentration. In the lab, we have seen CMCs of <10 ppm and >200 ppm of corrosion inhibitor. It depends on the concentration of active ingredients, well as water chemistry.

Yes. It is possible that corrosion inhibitor will be present in the system, and detectable with a residual test, but the concentration of the corrosion inhibitor will not be great enough to reach the CMC and therefore will not be detected by CoMic™ This might suggest that the inhibitor is present below the functional dosage and there may be an opportunity to increase the dose of corrosion inhibitor and reduce corrosion rate. If this is the case, or for systems known to be dosed below the CMC, samples can be ‘spiked’ with additional corrosion inhibitor prior to CoMic™ testing in order to estimate how far below the CMC the system is.

Another explanation is that the sample being tested has a property that interferes with the residual test. Oil or chloride ions can interfere with traditional ‘dye transfer’ methods. In this case, a falsely high residual result may occur, but the actual concentration in a sample may be very low, and no micelles are observed. We have seen this in our testing.