How can I define the impact of Gas Lift on well performance and facility throughput?

The following movie illustrates a typical procedure.

The following steps are required to invoke basic gas lift:

• Create a facility of the Gas Lift type in the Surface Layout.
• Feed it gas either by connecting its in connector to a facility which will supply gas-lift gas or by enabling the Gas Lift injection supply option in the facilityGeneral Tab (Facility).
• Connect those wells you will subject to gas lift to the Gas Lift facility. Notice that those wells will be now connected to two facilities: the facility production which will receive their output, and the gas lift facility which will help enhance their production.
• Go to the (automatically created) Gas Lift Installation job and provide the remaining inputs to characterize the installation: costs, gas required as a function of water cut, etc.

Well Performance (decline curve) Definition

1. If a well produces on natural flow for a period before gas lift is invoked by a Gas Lift Installation job. The Gas Lift option is designed to cater to this situation. Since the well will produce for a period on natural flow the performance curve defined in the Well Performance Tab should represent the natural flow decline (i.e. the production decline without gas lift). In this case, you should enter a Reserves Increase value in the Gas Lift Installation job. At the point in time when gas lift is installed, the well performance curve is then re-normalized to include the Reserves Increase amount. Depending on the shape of the well performance curve, this will also affect the well production rate at the gas lift installation point. The Reserves Increase should be defined so that the resulting re-normalized curve represents the production curve for the well when it receives enough gas-lift gas to meet the target Gas Liquid Ratio as defined in the table. Consequently, the factors entered in the Production Correction Table should represent the production reduction if Desired GLR is not met.
2. If gas lift is invoked by a Gas Lift Installation job prior to production start. The method described above can be used in this case as well. However, since the well will never produce on natural flow the inputs can be simplified. To simplify the input, the performance curve should in this case represent the production curve under the assumption that the well receives the target amount of gas-lift gas. The Reserve Increase value in the Gas Lift Installation job should be left at zero. As in the other option above, the factors entered in the Production Correction Table should represent the production reduction if Desired GLR is not met.