How to optimize a Gas Lift well of Petroleum Production?

How to optimize a Gas Lift well of Petroleum Production ?

How to optimize a Gas Lift well of Petroleum Production?

Before we know the answer of the question, we are going to see…
Petroleum Production: Gas Lift

1. Why we need Gas Lift?
2. Why we need the Gas Lift Valves?
3. How to unload a well?
4. How to optimize a Gas Lift well?

Gas lifting is a process of lifting fluids from an oil well by injecting gas into formation fluids at predetermined depth.
To achieve an efficient operation and to ensure that the proper amount of gas is injected at all times, gas entry must be controlled by utilizing some kind of downhole control device: Gas Lift Valves.

Unloading sequence
-After a well is completed or worked over, the fluid level in the casing and tubing is usually at or near the surface.
-Casing and Tubing are in hydraulic communication because the gas lift valve are in open position
-The gas lift pressure available to unload the well is generally not sufficient to unload fluid to the desired depth for gas injection. This is because the pressure caused by the static column of fluid in the well at the desired depth of injection is greater than the available gas pressure at the depth of injection.
-In this case a series of unloading gas lift valves are installed in the well for the purpose.
-These valves are designed to use the available gas injection pressure(depending on gas compression system characteristics) to unload the well until the desired depth of injection is achieved.

Gas Lift Optimization Concept is to Find the:
- Optimum injection point for stable flow conditions (at system design stage)
- Optimum quantity of gas to be injected to maximise the oil rate at specific well flow condition (during the production phase)