Asia Pacific Journal of Energy and Environment, Volume 1, No 2 (2014) Asian Business Consortium | APJEE Page 172 Pressure Data Analysis and Multilayer Modeling of a Gas-Condansate Reservoir Fatema Akter Happy, Mohammad Shahedul Hossain, Arifur Rahman Department of Petroleum & Mining Engineering, Shahjalal University of Science and Technology, Sylhet, Bangladesh ABSTRACT Kailastila gas field located at Golapgonj, Sylhet is one of the largest gas fields in Bangladesh. It produces a high amount of condensate along with natural gas. For the high values of GOR, it may be treated as a wet gas at reservoir condition. Three main sand reservoirs are confirmed in this field (upper, middle & lower).In this study, it has been shown that reservoir parameters of this gas field can be obtained for multilayered rectangular reservoir with formation cross-flow using pressure and their semi log derivative on a set of dimensionless type curve.The effects of the reservoir parameters such as permeability, skin, storage coefficient, and others such as reservoir areal extent and layering on the wellbore response, pressure are investigated.Shut in pressures are used in calculating permeability, skin factor, average reservoir pressure, wellbore storage effect and other reservoir properties. The direction of the formation cross flow is determined, first by the layer permeability and later by the skin factor.Finally, it is recommended to perform diagnostic analysis along with multilayer modeling to extract better results.Reservoir can also be considered as a multilayer cylindrical and can also use these models for other fields. Keywords: Pressure derivative analysis, skin factor, wellbore storage, permeability, multilayer INTRODUCTION Kailastila gas field is one of the largest gas producing fields in Bangladesh. The objectives of this study are to estimate reservoir properties by performing diagnostic analysis and to create multilayer model of Kailastila gas field. A common practice for development of multilayer gas and gas condensate fields involves wells producing commingled fluids from several formations that comprise one production target. For example, in West Siberia, multilayer fields producing from two or five or more formations are included in the commingled production zone. Although this practice can be economical in that it decreases the number of wells per field, simultaneous production This article is is licensed under a Creative Commons Attribution- NonCommercial 4.0 International License. Attribution-NonCommercial (CC BY-NC) license lets others remix, tweak, and build upon work non-commercially, and although the new works must also acknowledge & be non- commercial. How to Cite: Happy FA, Hossain MS and Rahman A. 2014. Pressure Data Analysis and Multilayer Modeling of a Gas- Condansate Reservoir Asia Pacific Journal of Energy and Environment, 1, 172-181. Source of Support: Nil Conflict of Interest: Non declared