TY - THES

T1 - Gas Lift Design Optimization

AU - Trichili, Sirine

N1 - embargoed until 18-05-2022

PY - 2017

Y1 - 2017

N2 - The purpose of this study is to evaluate the current gas lift design procedure used in OMV Gänserndorf and compare it to different design procedures (API and Petroleum Experts using PROSPER software). The aim is selecting the best design practice out of the investigated methods and developing a digital tool to simplify the design process. In order to achieve this goal, these design procedures were researched and the concepts are explained within this work. In addition to the theoretical background, these procedures were compared to each other by testing them on several wells varying in characteristics namely the depth, the production rate, the productivity index, etc. Out of the results, a best practice is drawn and a Microsoft Excel tool was developed which enables the user to design a gas lift system quicker and in a more efficient way. The differences between the investigated designs from an injection volumes and production rate point of view arise mainly if the well’s productivity index is high enough. The comparison of the different design procedures resulted in the fact that the current OMV procedure is the safest from a valves performance point of view. This means that the OMV design guarantees that the unloading valves would close and they could be opened selectively. When it comes to PROSPER, the safety factors are fixed, not allowing the injection depth to reach higher values. The API design allows reaching deeper injection points. However, the valves closing is not always guaranteed. To this end, the recommended best practice in this study is to continue with the current design used in OMV with incorporating safety factors for injection. The magnitude of the safety factors remains a function of the quality of the provided data as well as the well’s productivity.

AB - The purpose of this study is to evaluate the current gas lift design procedure used in OMV Gänserndorf and compare it to different design procedures (API and Petroleum Experts using PROSPER software). The aim is selecting the best design practice out of the investigated methods and developing a digital tool to simplify the design process. In order to achieve this goal, these design procedures were researched and the concepts are explained within this work. In addition to the theoretical background, these procedures were compared to each other by testing them on several wells varying in characteristics namely the depth, the production rate, the productivity index, etc. Out of the results, a best practice is drawn and a Microsoft Excel tool was developed which enables the user to design a gas lift system quicker and in a more efficient way. The differences between the investigated designs from an injection volumes and production rate point of view arise mainly if the well’s productivity index is high enough. The comparison of the different design procedures resulted in the fact that the current OMV procedure is the safest from a valves performance point of view. This means that the OMV design guarantees that the unloading valves would close and they could be opened selectively. When it comes to PROSPER, the safety factors are fixed, not allowing the injection depth to reach higher values. The API design allows reaching deeper injection points. However, the valves closing is not always guaranteed. To this end, the recommended best practice in this study is to continue with the current design used in OMV with incorporating safety factors for injection. The magnitude of the safety factors remains a function of the quality of the provided data as well as the well’s productivity.

KW - Gaslift

KW - design

KW - Software Prosper

KW - petroleum experts

KW - API

KW - gas lift

KW - artificial lift

KW - design

KW - method

KW - production

KW - optimization

KW - PROSPER

KW - Petroleum Experts

KW - PETEX

KW - well performance

KW - IPR

KW - VLP

KW - geothermal recovery

KW - economic evaluation

KW - comparison

KW - API

M3 - Master's Thesis

ER -