Production deferment due to wellbore sanding issues is a major risk for heavy oil field development. The heavy oil reservoir in Kuwait is a multi-stacked unconsolidated formation, which is prone to sanding. Currently there are two steam flood pilots in inverted 5-spot pattern configuration with pattern areas of 5 and 10 acres. The wells were operated for two cycles of Cyclic Steam Stimulation (CSS), before their conversion to steam flood.
Different Sand Control equipment is field tested in some pilot wells to optimize production in this viscous oil-saturated unconsolidated sandstone reservoir. This paper will discuss the operational challenges and the difference in the performance of cold production and after thermal CSS cycles of the installed Stand-Alone Sand Screens (SAS), which were retrofitted in the pilot wells. The mesh size of the SAS was designed based on the particle size distribution and well operating condition.
A comprehensive reservoir and well surveillance program was conducted to monitor and gather necessary data to characterize the reservoir and well performance in the pilot wells equipped with sand control equipment. The primary objective was to determine the optimal sand control strategy, moving forward in to the commercial phase of field development.
This paper will discuss the learnings from the pilot wells. The various SAS used were partially successful in mitigating sand production. More piloting with advanced sand controlling technologies at both laboratory and field levels may be required to reach to the optimum design for the field-specific cases.
The well trials using SAS was mainly to assess the screens regain permeability (skin) versus crude oil production while minimizing sand movement within the wellbore. This helped to improve the artificial lift pump run life and minimize sand debris from entering the pump.