Estimation of Sand Settling Time in Heavy Oil

Abstract

Sand production is a major concern for the efficiency of conventional and heavy oil production operations and facility equipment. Sand production could cause problems during well workovers, well and facilities clean-up, and waste sand removal. Understanding the sand production phenomena is essential to control it and to prevent losses to oil production operations, especially when producing from unconsolidated formations. Sand movement depends on many parameters such as particle size and carrying fluid viscosity. The objective of this work is to investigate, experimentally, the sand settling time of Lower Fars (LF) heavy oil formation during production. LF is located north of Kuwait. It is an unconsolidated formation. The effect sand particle size and oil viscosity on the settling time was investigated. The results showed that there was a trend of settling time as a function of particle size and oil viscosity. As particle size increased, its settling time decreased. Also, it was observed that as the oil viscosity increased, the particle settling time increased. Moreover, the sand settling velocities was irrelevant to sand particle size at high viscosity. A mathematical model was developed to obtain the sand settling velocity (w) at any particle size and oil viscosity.