Experimental studies of the removal properties of liquid and solid foaming surfactants

Using the laboratory model of a well, foaming and removal properties of liquid and solid surfactants (savenol, light and dark stinol, Sofir M2, TEAS and Nadra) are studied. The authors determine experimentally the height of the level of the foam in the glass column at the end of the foam-forming process and the duration of re-moving half volume of liquid out of the foam. Using height and duration values, the authors determine the multi-plicity and stability of the foam. Based on the results of experiments on the laboratory model of the well, a graph-ical dependence of the multiplicity and stability of the foam on the mass concentration of surfactants in fresh and salt water, in mineralized water with the addition of hydrocarbon condensate for various temperatures is con-structed. Based on the results of experimental studies, the influence of the concentration of surfactants in a foam-ing liquid, the salinity of water, hydrocarbon condensate and temperature on the foaming ability of liquid and solid surfactants for the removal of liquid from watered gas and gas condensate wells is analyzed. The authors determine the optimal values of the concentrations of foaming surfactants in aqueous solutions. Above these val-ues the multiplicity and stability of the foam varies slightly. It has been established that the outflow properties of the solid Nadra surfactant are the best in saline water and in solutions with hydrocarbon condensate, in contrast to the investigated liquid surfactants. Based on experimental studies, the patterns of foaming of aqueous surfac-tant solutions with modeling bottomhole temperature (from 20 to 80 °) are established. The authors recommend the use of various types of surfactants under different operating conditions of wells with a high fluid content in the well production. Foaming surfactants are supplied to the bottom of the well in the form of aqueous solutions and samples of solid surfactants. As a result, the foamed formation fluid brings to the surface not only the liquid phase, but also the solid particles that accumulate at the bottom due to corrosion of the pipe metal, the destruction of cement stone and rock of the bottomhole formation zone.