Pearl GTL - Assuring Success From the Beginning
Authors: Denney Dennis 
Published: February 2015

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper SPE 118290, "Pearl GTL - Assuring Success From the Outset," by Andrew Brown, Qatar Shell GTL, prepared for the 2008 Abu Dhabi International Petroleum Exhibition and Conference, Abu Dhabi, 3–6 November. The paper has not been peer reviewed.

The Pearl gas-to-liquid (GTL) plant will be the largest energy project in Qatar. In spite of various challenges that are intrinsic to such a project, Shell and Qatar Petroleum are confident of managing construction successfully.62 Offshore activities include drilling wells and constructing platforms and pipelines. Onshore, the detailed design is nearing completion, and procurement activities are proceeding.

Introduction

The Pearl GTL project is fully integrated upstream/downstream in Ras Laffan Industrial City, 80 km north of Doha. It will have capacity to produce 140,000 B/D of GTL products, including fuel oil, naphtha, kerosene, normal paraffin, and lubricants, as well as 120,000 bbl of oil equivalent per day of ethane, liquefied petroleum gas (LPG), and condensate. The project is being developed in two phases, with the first phase expected to start up in 2010. Overall, it is more than 50% complete.

Project Description

Upstream, the project involves offshore development of a North Field block to produce approximately 1.6 Bcf/D of gas. The offshore scope includes 22 development wells, two unmanned wellhead platforms in 30 m water depth and two 60-km-long 30-in. pipelines to shore. Onshore gas-processing facilities will treat the sour, rich wellhead gas to produce a sulfur-free, lean-gas feedstock for the GTL plant and treated ethane, LPG, condensate, and pure elemental sulfur as a by-product.

The project uses proprietary Shell GTL technology, with 15 years of operational experience at the Bintulu, Malaysia, GTL plant. Although Pearl is approximately 10 times the size of Bintulu, scaleup was achieved by replicating smaller units, such as multiple parallel reactors, to minimize technical risk. A startup methodology has been applied from the outset, whereby potential problem conditions and flaws are identified and addressed.

Work began in February 2002 with a scoping study. Project authorization was granted in July 2006. To counter constraints in the engineering, procurement, and construction, including a shortage of capacity in many areas and rising prices, a contracting strategy was applied that aimed at giving access to a wider range of contractor resources and creating competition, while retaining close control over areas in which proprietary technology was involved.

Offshore Development

The engineer, procure, construct, and install contract for two wellhead platforms was awarded in June 2006. The main initial focus was on the jackets and temporary drilling decks, which were installed in 28 to 35 m of water in March/April 2007 to allow early drilling activities. Meanwhile, work continues on fabrication of the two 2000-tonne topsides to meet the planned offshore-installation schedule once drilling is completed. Trenching/dredging began in 2008, and a pipe-laying barge is expected in early 2009.