Assessment of Deliverability of a Natural Gas Gathering and Production System: Development of an Integrated Reservoir – Surface Model

摘要

The present work describes the development of a one-dimensional steady state isothermal reservoir – surface gas pipeline network model. The model was developed by combining reservoir with surface facility description parameters to effectively capture the variations in reservoir flow dynamics with changes in surface network operating conditions. The developed mod- el is an extension of the general pipeline network model where the deliverability from the wells are calculated in addition to the nodal pressures and gas flows in different pipe sections in the system based on a set of operating conditions. Validation of the developed model was done by history matching using field data obtained from a currently operating gas gathering and transportation network located in the Northeastern, United States. After successful validation, the model was used as a diag- nostic tool to evaluate ‘what if’ scenarios to identify the pressure and deliverability changes that can happen in the network. 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 re- sponse 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.