Pulau Bukom Refinery, Singapore

Shell Eastern Petroleum, a unit of Royal Dutch / Shell Group (RD) and Petrochemical Corp. of Singapore announced in May 2000 that their jointly owned 70,000bpd condensate splitter unit had commenced operations.

The splitter, jointly owned by Shell and PCS and situated at Shell's 59,000t/day Pulau Bukom refinery, started up on 24 May 2000, and reached full capacity in early June, however Shell refrained from giving exact production levels. The unit began processing condensate feedstock from Australia into on-specification-grade naphtha, which is being taken by PCS under a term agreement.

The project required an investment, which was valued in the region of $100m. Shell and PCS shared the investment costs in the splitter project on a 50-50 basis.

PIPELINE BUNDLE

The lead contractor for the project was Kvaerner. Under the terms of the contract the company was required to install a pipeline bundle to convey naphtha and other products from Singapore port to Jurong Island. The bundle needed to stretch 4.5km on the seabed. Kvaerner used a technique known as bottom pull to achieve the task, which would be otherwise hampered by the intense port traffic.

Pioneered by Kvaerner, bottom pull effectively means pulling a pipeline from one shore across the seabed to the next shore. It is particularly suited to exceptionally active marine areas like Singapore port, where conventional techniques, such as lay barge and surface tow, would cause too much interference.

The pipeline is used to link the new condensate splitter unit on the island of Pulau Bukom with downstream users on Jurong Island. The submarine pipeline bundle, which initially will carry naphtha to the Petrochemical Corporation of Singapore's facility on Jurong Island, will be over 4.5km in length and 28m deep in parts.

It consists of eight pipelines and two fibre-optic cables, giving a combined pipeline length of over 36km. The pipelines themselves are fabricated from 12m pipe lengths. They are then welded into 250m lengths, known as strings, before being assembled into a bundle of eight with a series of cross-braces.

The double-armoured fibre-optic cables will be fed into the bundled sections as they are pulled across the bottom of the marine fairway by a pulling cable. This uses a special linear winch to generate a pull capacity of over 350t. The maximum linear velocity when pulling is about 4m a minute, although this does depend on local conditions.

Singapore legislation demands that the bundle be protected by a layer of armour rock, to prevent damage from anchors and other dropped or dragged objects. The seamless pipeline was supplied by Sumitomo in Japan. 100% radiography of all welds and careful handling of the pipelines during installation was ensured, as once covered by the layer of armour rock, any leaks would be very hard to deal with.

ROCK ARMOUR PROTECTION

Anchor model tests have been carried out by a research institution in Australia to check the design basis of the rock armour protection. Utilising scale model tests, various anchor sizes are tested to ensure that rock armour will perform under a variety of different conditions, for example, anchors being dropped directly onto the rock armour and also being dragged across the rock armour-protected bundle. Tests showed that the design basis for the armour rock is more than adequate to protect the pipeline bundle.

Now in place, the pipeline is being closely monitored by a regime which includes online leak detection and regular intelligent pigging. Coupling this with a heavy-duty cathodic protection system, which is good for a design-life of 50 years, ensures lifelong pipeline integrity. Kvaerner's main dredging subcontractor was Van Oord ACZ of Holland. The main subcontractor for the fabrication of the pipeline bundle was McConnell Dowell of Australia.

ETHYLENE GLYCOL PLANT AT JURONG

In a related project started in August 2006 Foster Wheeler Ltd announced that its UK subsidiary, Foster Wheeler Energy Limited (FWEL), and its Singapore subsidiary, Foster Wheeler Asia Pacific Pte. Ltd (FWAPPL), were instructed by Shell Eastern Petroleum (Pte) Ltd (SEPL) to proceed with the initial Engineering, Procurement and Construction management (EPC) for a large-scale Ethylene Oxide / Mono-Ethylene Glycol (EO/MEG) plant and a significant refinery modification project in Singapore.

FWEL has already completed the Basic Design and Engineering Package (BDEP) for the new EO/MEG plant, which uses Shell's proprietary 'Omega' technology. Foster Wheeler's Asia Pacific operations have completed the BDEP for the modifications to the Bukom Refinery and project specification for sulphur recovery and high vacuum units.

Foster Wheeler will now carry this work through into the implementation phase. The new 750,000t a year EO/MEG plant, to be located on Jurong Island, will use feedstock from an ethylene cracker to be built by others on Bukom Island, Singapore.

Both the cracker and the EO/MEG plant are part of a project known as the Shell Eastern Petrochemicals Complex (SEPC), which includes in its scope the construction and integration of the new facilities with Shell's existing refinery at Bukom to capture the benefits of oil-chemicals integration.

During the final quarter of 2006 SEPL broke ground for its petrochemical complex located at the Pulau Bukom refinery in Pulau Ular, Singapore. The complex, which is known as the Shell Eastern Petrochemical Complex, is due to become operational by the end of 2009 or early 2010.

ETHYLENE CRACKER

At the end of 2005 a joint venture between Japan's Toyo Engineering and ABB Lummus Global of the US announced that it had been awarded a contract to provide the Basic Design and Engineering Package (BDEP) for the SEPL ethylene cracker.

It is expected that the facility will have a capacity of between 1mtpa and 1.3mtpa. The joint venture partners added that following a final investment decision by SEPL the BDEP contract would roll over into an engineering procurement and construction management phase. The cracker will be based on propriety technology supplied by ABB Lummus Global. It will be integrated into the existing refinery.

Click here for printable version