ASSESSMENT OF DELIVERABILITY OF A NATURAL GAS GATHERING AND PRODUCTION SYSTEM: DEVELOPMENT OF AN INTEGRATED RESERVOIR - SURFACE MODEL

Open Access
Author:
Alexis, Dennis Arun
Graduate Program:
Petroleum and Mineral Engineering
Degree:
Master of Science
Document Type:
Master Thesis
Date of Defense:
October 16, 2009
Committee Members:
  • Luis F Ayala H, Thesis Advisor
Keywords:
  • deliverability
  • IPR
  • gas networks
  • integrated model
Abstract:
Natural gas gathering and distribution systems serve as the primary means to transport gas from the wellhead to the customer. A network designed on sound engineering principles helps to maximize the deliverability from the wells with minimum energy loss during transportation. To achieve this objective, pipeline network models help in characterizing the system to understand the behavior of the network under different operating conditions. In this study, a one dimensional steady state isothermal integrated network model was developed by combining reservoir with surface facility description parameters to effectively capture the variations in flow dynamics with changes in network conditions. In this study, the typical constant supply specification of network analysis was relaxed by implementing gas well deliverability equations at all supply nodes in the system. This model is an extension of the general pipeline network model where the deliverability from the wells are predicted in addition to the nodal pressures in the system based on a set of operating conditions. The model was history matched to the production data from a gas gathering and production system located in Snow Show, Pennsylvania by adjusting the performance constant of the well for a predetermined unique well shut in pressure. With this basic deliverability model in hand, the network was evaluated for several if-then scenarios related to proposed captive modifications to be carried out to analyze the pressure and deliverability changes in the system. Based on the model predictions, recommendations were made to the operator in terms of total production, total sales and fuel consumed by the compressors present in the network. This integrated modeling approach helped in analyzing the system response as a whole and gave a good insight of how the well shut in pressures used in the model had a significant impact on the deliverability predictions.