Production optimization of Kailashtilla gas field

Abstract

The study focuses on the utilization of Integrated Production Modeling (IPM) of Kailashtilla gas field located in western region of Bangladesh. The gas field has three producing wells with a processing facility of 90 MMscfd gas dehydration plant. The field reserves are primarily contained within three distinct sands: Upper Gas Sand (UGS), Middle Gas Sand (MGS) & Lower Gas Sand (LGS). Later New Gas Sand (NGS) is also identified in this structure and in production from 2012. Currently, the field produces around 70 MMscfd gas and 600 bbld condensate through three producing wells in UGS and one in NGS. The previous reservoir engineering study estimated the reserve of this gas field as 3.54 TCF in the year 2009. The ultimate goal of this study is to re-estimate the gas reserve and discover an optimum field development strategy based on gas recovery factor, plateau duration and economic outcome. The complete task was divided into three segments: reserve estimation, future performance prediction and economic analysis of different predictive cases for finding the optimum development plan. It involves integration of all reservoirs, wells & surface facilities in an integrated model to investigate several field development strategies with varying production system that include upgrading separator, changing tubing size, lowering separator pressure along with compressor installation and finally adding new well in the system network for determining the optimum development plan. An economic analysis in the form of net present value & benefit-cost ratio of different prediction cases has been performed to find out most cost effective production plan. This study estimates the reserve of the gas field as 3.013 Tcf by material balance method, from where, 2.17 Tcf are in UGS, 0.647 Tcf are in MGS & 0.197 Tcf are in LGS. During reservoir modeling, an active aquifer support has been found for these three productive sands.