Gas lift is typically installed on a well after it can no longer free flow. The primary difference in the downhole equipment between a free flowing and gas lifted well is that the tubing in a gas lift well includes mandrels with gas lift valves. The gas lift valves allow gas to enter the tubing from the casing and lower the density of the fluid column in the tubing.

It is also critical to understand the operation of a typical reciprocating compressor providing the lift gas.

A separator is a pressure vessel used to separate a well stream into different components. A two-phase separator separates a well stream into gas and liquids. A three-phase separator, also sometimes referred to as a free water knockout (FWKO), separates a well stream into oil, gas, and water.

Safe operating procedures must be followed when performing high risk tasks such as lighting fired vessels. 

Lighting a heater-treater is a common practice requiring proper isolation of fuel sources, verification that no flammable atmospheres are present, and safe ignition of the fire tube. Below is a sample walkthrough of a lighting procedure