Production optimization of a natural gas field considering different options including gravel pack design of sand producing well

Abstract

The study focuses on the utilization of Integrated Production Modeling (IPM) of Subjected Gas Field located in South-Eastern region of Bangladesh. The gas filed has five wells while four are producing with a processing facility of 120 MMscfd gas dehydration plant. Currently, the field produces around 95 MMscfd gas and 280 bbl/d condensate. A study in 2006 estimated the reserve of this field as 0.476 Tcf. Currently the field is struggling to maintain a plateau rate due to depletion. It is therefore necessary to adopt an optimized production and development strategy for this field. The goal of this study is to re-estimate the gas reserve and suggest an optimum field development strategy based on gas recovery factor and plateau duration. The task was divided into several steps, including reserve estimation, gravel pack design for the sand producing well and future performance prediction for 20 different scenarios. The work involves integration of reservoir, wells and surface facilities in an integrated model, several field development strategies with varying production system were investigated. These include reviving the shut in well, lowering separator pressure, installation of compressor, and adding an infill well. This study estimated the reserve of the field as 1.23 Tcf by material balance method. Comparative analysis of the various predictive cases suggests the following optimum development strategy a) Installation of compressor in wellhead along with infill well, resulting in maximum recovery 77.45% b) tie-in sand producing well with gravel pack, resulting in maximum recovery 69.24%. A recovery factor 60.27 % is achievable using the current field production strategy.