Floating Regasification Terminals - Selection And Marinisation Of Regasification Equipment For Offshore Use
Authors: Kelle Holger , Wong Yee-jun , Schlatt Jorg 
Published: May 2011

This paper presents an overview of existing regasification technologies, discusses key marinisation issues and their adaptability and design for offshore use as well as consideration of the environmental impact. To assist in the development of a high level CAPEX critical for early project feasibility studies, key cost drivers associated with marinisation will also be discussed.

In the context of rising global energy demand and lack of space for shore-based regasification terminals, the use of floating regasification developments are on the rise. The success of floating regasification terminals lies in the design of the regasification and process equipment, which needs to maintain high availability at the required regasification rate whilst under the influence of offshore environments and ship motions. Furthermore, for floating regasification facilities that are permanently moored offshore, the regasification equipment will also need to withstand the harshest marine environments. The regasification equipment therefore needs to be designed for offshore operations and survivability.

Marinisation is a common approach used in the design of offshore floating production facilities (FPSOs) and extending this concept to floating regasification involves adapting existing and proven shore/land based regasification equipment for the offshore environment. In addition to ensuring operability, requirements for high availability influence the equipment layout and placement on deck to minimize repair downtimes.

This paper is targeted towards projects or developments centered around permanently moored, offshore floating regasification terminals. The number of such terminals currently planned or in development is on the rise in South East Asian countries where the main purpose is to provide base load regasification where gas demand is constant and set to increase on a year-by-year basis. In contrast with the Atlantic floating regasification terminals, where only seasonal demands are required to be met, a base load terminal calls for a stricter requirement in terms of availability and offshore survivability, and hence the approach to marinisation for base load terminals is different to that for seasonal load terminals.

Introduction

One of the means of supplying natural gas to coastal markets is by importing liquefied natural gas (LNG) from distant, often overseas, suppliers and subsequently converting the LNG back to its gaseous state prior to injection into the gas supply grid. The process of vaporizing LNG to gas is referred to as regasification.

Shore-based regasification terminals, which includes land-based and near shore jetty based terminals, have been in operation for several decades and the regasification technologies used on such terminals are mature and proven. However, shore-based regasification terminals generally require large land space.

When combined with the lack of shore space, large capital cost and long duration needed to develop such terminals, as well as the emerging issues of NIMBY (Not In My Backyard) and public perception, the only alternative is to move to an offshore based terminal solution. One such offshore solution that addresses these issues is the floating regasification terminal, which combines LNG storage and the regasification equipment on a single moored floating vessel/hull. Such floating terminal is commonly known as Floating Storage Regasification Unit (FSRU).