Process Technologies and Considerations for Gathering Associated Gas: Experiences from the Niger Delta, West Africa
Authors: Nwasike O.T. , Okwuokenye C.N. , Nwagwu N.H. 
Published: October 2008

This paper discusses the issues and challenges which are being experienced in implementing process technologies for gathering, processing and transporting associated gas from remote fields in the Niger Delta, West Africa.

The Niger Delta has a significant amount of natural gas. Whilst exploration efforts to date have focused primarily on oil, some 20 billion barrels of oil equivalent (boe) of gas is reflected in published records. This is compared with some 25 billion barrels of oil reserves.

In the process of producing nearly 2 million barrels of oil per day, some 2,000 MMscf/d of associated gas is currently being flared. As a result of global environmental concerns, operators are now placing new infrastructure and systems to handle these volumes. A major initiative in this direction is the Shell led LNG project that commenced operation in Bonny Island in October 1999. Other projects are in various stages of completion. In the final event, associated gas will be gathered and processed for transportation to point of sale in local and foreign markets.

The challenges of reducing the flaring burden offers many business opportunities to both local and foreign entrepreneurs. Orders are being placed with international manufacturing firms and service providers for process equipment supply, installation and operations/ maintenance services.

Additionally, the first steps are being made towards ensuring improvement in the business and political climate in Nigeria, following the emergence of democracy in May 1999. This new climate has enabled increased confidence and as a result, joint ventures alliance arrangements are being created between local firms and foreign partners.

Introduction

Historical Perspectives.

Oil and gas prospecting commenced in Nigeria in 1908, with the acquisition of a licence for the development of bitumen resources by a German company. Commercial discoveries of crude oil were not made until 1952, after some fourteen years of seismic data acquisition and exploration drilling by Shell D-Arcy.

Nigeria's first export of crude oil was achieved in 1958 from Shell's crude oil export terminal at Bonny. At the beginning of the 21st century, Nigeria produces about two million barrels of oil per day. With the commissioning, in October 1999 of an LNG processing plant in Bonny, Nigeria is also an exporter of LNG parcels to overseas customers. Meanwhile, with some 148 concessions held by fifty-seven companies, the pace of prospecting for oil and gas reserves continues unabated in the Niger Delta as well as in the six other sedimentary basins of Nigeria.

Country Data.

Nigeria has a population of about 110 million people. Some 52% of its population are in the age bracket 15 to 64 years and a population growth rate of about 3.05% is recorded (1997 estimates). Over 500 languages are spoken, including English, the official language. Official records indicate a literacy rate of about 57% (1995 estimates). Located in Western Africa between Benin and Cameroon, it borders the Gulf of Guinea on its southern flank where (in the Niger delta) most of Nigeria's hydrocarbon development activity is carried out.