The Tangguh LNG Gas Fields: Conceptual Development Overview

Abstract

Recent exploration, appraisal and certification activities have established certified proved gas reserves in excess of 14 trillion standard cubic feet (TCF), and potential reserves of 24 TCF, for the fields already identified in Berau Bay, Irian Jaya, Indonesia1. The project to develop this gas resource has been named Tangguh LNG. This project encompasses production and processing of natural gas to manufacture liquefied natural gas (LNG) plus storage, loading and shipping for markets in the Asia-Pacific region. The goal of Tangguh LNG is to create a positive, progressive development with mutual benefit to business and the community in which it is operated - and which does no harm to the environment. This paper describes some of the conceptual upstream development planning that has been carried out in support of the Tangguh LNG project. The conceptual development planning is based on the data from an extensive drilling and seismic campaign that was conducted to establish the magnitude of the gas reserves found mostly offshore in six fields, including the giant Wiriagar Deep and Vorwata gas fields. The resultant integrated dataset contains substantial log, core, pressure, drill stem test and seismic information and was the basis for the reservoir and fluid descriptions used in models for conceptual planning. Both analytical and numerical simulation models have been used for conceptual development planning. Single well analytical models have mainly addressed well deliverability. Simulation models have been used to investigate the interaction of several major reservoirs in the six gas fields, an aquifer, and a surface network supplying gas to the LNG plant. Pipeline simulation models have been used to investigate the possible use of multiphase pipelines to supply gas to the plant, thereby simplifying the offshore facility design. For conceptual development planning, the scope of initial development for the Tangguh LNG project has been designed for a two train LNG plant with an average sales volume of 6 MTPA. Highly prolific wells, a large reserve base, and an uncomplicated offshore development setting result in an efficient, low cost, and highly reliable LNG project for this design basis. Introduction The Tangguh gas fields are located in the Berau Bay of western Irian Jaya, Indonesia. Figure 1 shows the Tangguh Project location with respect to the countries in the Asia Pacific region. The proposed development plan for the Tangguh fields calls for production of natural gas from the currently identified reservoirs, transportation of this gas to a new LNG processing plant and processing of this gas into LNG. The Tangguh project is ideally suited for LNG having a large reserve base and being located in close proximity to existing Asian LNG markets. The giant Wiriagar Deep and Vorwata gas fields, which hold certified proved reserves in the excess of 13 TCF, form the back-bone of the Tangguh Development Project.