Prevention of corrosion and salt deposition by inhibiting foam systems in wells of North-West Bashkortostan fields

Abstract

At the late stage of development of oil fields in Bashkortostan, well operation is accompanied by corrosion and salt deposition in underground equipment. The study of elemental composition of accumulations and sediments carried out with the help of energy dispersive X-ray spectrometer "Mini Pal" allowed to determine more precisely the mineral composition of sediments. Traditional methods of corrosion and salt deposition control do not allow to effectively protect the wellbore space. A fundamentally new method of equipment protection was developed and tested, which consists in injection of a composition inhibiting corrosion and salt deposition in a foamy form into the annular space. Tests of the proposed technology conducted at the Arlanskoe field allowed to establish the mechanisms of corrosion rate change after treatment and to work out the treatment technology. The treatments provided 2.3-2.9 times increase of effective protection period. The use of nitrogen as a foaming agent makes the technology commercially safe and environmentally friendly.