Application of multifunctional fluids to improve hydrocarbon production.
Ewa Knapik, Jerzy Stopa
Vol. 30, no. 1 (2013), s. 117-124, 
In the course of the mature gas fields exploitation there are many technical problems including the corrosion damage, formation of hydrates and water cut. In many cases, an effective solution of these problems is the dosage of appropriately selected chemicals. Commercially available corrosion inhibitors, hydrate inhibitors, demulsifiers and foaming agents are injected in a form of single, multifunctional mixture through one liner which reduces injection costs. The paper presents the results of laboratory tests, which aim was to investigate synergism and antagonism in multifunctional mixture containing different commercially available surfactants, corrosion and hydrate inhibitors. Correlations between final product composition and performances such as liquid unloading efficiency, corrosion protection and pour point were studied. The described approach allows to adapt the tertiary mixture composition (foaming agent + corrosion inhibitor + hydrates inhibitor) to the current production conditions. The polarization behavior of electrodes in brines with and without mixture of additives has been studied by a cyclic voltammetric method. The addition of increasing concentrations of each chemicals causes the reduction in the corrosion current density. The measurements using a modified method of the US Bureau of Mines show synergistic effect of surfactants and corrosion inhibitor on foamabilities. Multifunctional mixtures are stable under storage conditions and not cause any compatibility problems with reservoir fluids.