Abstract
Corrosion inhibitor (CI) residual measurements have been a decades-long source of frustration for chemical vendors and oilfield operators alike. These measurements are often expected to detect small amounts of CI in a complex matrix of interfering species. The authors have developed a new technique utilizing nanomaterials coupled with surface-enhanced Raman spectroscopy (SERS). This new SERS technique is capable of accurately and precisely detecting trace amounts of several corrosion inhibitors at sub ppm levels. A robust field protocol was developed for sample collection, sample preparation, and calibration to allow reliable field analysis.
In oil transport pipeline systems it is operationally important that small concentrations of CI are transported through the oil to the areas where low amounts of water may be present in the system. The residual technique discussed in this paper has shown that one CI is transported in sufficient quantity to the areas where low amounts of water are collected. The new SERS technique is allowing operators to know with a high degree of certainty that the products selected for their pipelines are correct and effective. This residual technique in conjunction with corrosion monitoring empowers the operator to select a better performing product for a longer pipeline service life or to optimize the cost of treatment of their pipeline while still maintaining an optimal service life.
