Expert Viewpoint - Artificial Lift

An overview of current practice and future trends in AL systems for improving heavy oil production.

Several challenges must be overcome when designing effective AL systems for heavy oil, including:

Viscosity

It is important to ensure sufficient inflow of produced fluids; otherwise it is difficult or impossible to design an effective lift system.

Mechanical devices are prone to extra stress and strain when handling high viscosity fluids.
High viscosities require high horsepower consumption.
There are pump fillage and rod fall issues, particularly with reciprocating rod pumps.

Sand production

Sand production from unconsolidated reservoirs causes abrasion, particularly to metal components- a key source of equipment failure.
Heavy oil is effective in carrying large amounts of sand; however the AL system design must ensure sufficient velocity to carry the sand out of the well to the surface.

Variable production rates

A wide variety of solutions is required to handle the considerable variation in production rates between different oilfields and individual wells and the type and stage of recovery method utilized.

Temperature

Thermal recovery methods present a number of challenges for the selection of well completions and artificial lift systems. Understanding and compensating for temperature ranges and types of materials are important to ensure system reliability.