Chapter 12 - Electric Submersible Pumps

Abstract

This chapter discusses electric submersible pumps (ESPs), which are typically reserved for applications where the produced flow is primarily liquid. High volumes of gas inside an electrical pump can cause gas interference or severe damage if the ESP installation is not designed properly. Free gas dramatically reduces the head produced by an ESP and may prevent the pumped liquid from reaching the surface. In gas reservoirs that produce high volumes of liquids, ESP installations can be designed to effectively remove the liquids from the wells while allowing the gas to flow freely to the surface. ESPs can be a viable method to de-water gas wells, usually when it is necessary to handle large liquid volumes. Generally, ESPs are considered only when water rates exceed at least 100 bpd. But if high rates are needed, they become much more advantageous. Small water well ESPs are used to lift relatively small rates off of coal gas wells. ESP installations are expensive and usually consume a little more power per barrel of liquid lifted than a beam pump system. The efficiency of an ESP system is significantly reduced when gas is allowed to enter the pump. These shortcomings limit the use of ESPs for gas well de-watering applications. The use of ESPs to inject water below a packer at fairly high rates is a specialty area for ESPs for gas well operations.