Laboratory Methods for Scale Inhibitor Selection for HP/HT Fields

Abstract

HPHT (high pressure, high temperature) conditions create challenges and push the limits of existing technology (i.e., scale prediction modeling, testing methodology and instrumentation) and commercial scale inhibitor chemistry. Scale prediction modeling often fails at HPHT conditions and laboratory testing under appropriate field conditions have to be compromised due to instrument limitations. This paper details work done under high temperature (204°C) and elevated pressure (3,000 psi) conditions in in order to obtain effective scale control. More specifically, this paper will discuss selection methods for continuous and squeeze scale inhibitor application via dynamic performance testing and coreflood studies for scale control in this deep-water oil production field. The technical challenges encountered such as matching the scale type predicted in the prediction software to the scale observed during dynamic tube blocking will be outlined. Thermal ageing procedures/performance testing for continual injection chemicals and performance testing of coreflood effluent from HT coreflood studies will be outlined.