Corrosion Inhibitor Efficiency Limits and Key Factors

The selection of corrosion inhibition in combination with carbon steel is an economically preferable corrosion control strategy for many oil & gas projects.

 The traditional approach to evaluate the viability of corrosion inhibition combines an assessment of corrosion inhibitor efficiency and availability.  It is often assumed that an inhibited rate of 0.1mm/year can be achieved and focus is given to the desired availability.

 New projects are exploiting reservoirs with fluids of increasing complexity and more aggressive environments.  Therefore, achieving a high inhibitor efficiency is key to project delivery and integrity risk management.

 Extensive inhibitor testing data has been reviewed across a range of environmental conditions.  The influence of environmental parameters (including corrosivity, temperature, brine salinity and hydrodynamics) on inhibitor performance has been analysed.

 The effect of the parameters and relative criticality to achieving acceptable inhibitor performance has been defined and a matrix has been developed to enable assessment of the likelihood of achieving successful inhibition.

 Test data is presented to support the analysis.