Primary Recovery and Well Stimulation

Abstract

Once a well has been drilled and completed, and is ready to enter production, it is the role of the petroleum engineer to develop a strategy that will optimise the amounts of oil and gas to be produced from the well. The engineer will need to consider how to maximise both the rate at which oil or gas is produced from the well, as well as the overall amount of hydrocarbons that can be economically recovered. Many different techniques exist to both stimulate oil and gas production, and to aid the reservoir fluids to get to the surface. These techniques may broadly be categorised into one of three classifications: primary recovery, secondary recovery and tertiary recovery. This chapter considers primary recovery techniques with an emphasis on the use of different types of pumps and other means of artificial lift. We will also consider several different techniques for stimulating flow from a well. Over the past century a range of techniques, collectively known as artificial lift, have been developed to overcome the hydrostatic pressure imposed by a column of liquid standing in a well. Each technique has its advantages and limitations with some being ideal for particular reservoir conditions. The main artificial lift techniques now in use are covered in this chapter and include sucker-rod pumping, electric submersible pumping, gas lift, progressing cavity pumping, hydraulic pumping and plunger lift. We also consider well-stimulation techniques including fracturing and acidising.