Platform dismantlers aiming for 99% plus recycling levels

Examples of North Sea platforms recently decommissioned by Able UK on Teesside, some for re-use as office blocks.

The Able Group of companies has been involved with decommissioning for 30 years, adapting its techniques for offshore abandonment since 1985. Catering today for all decommissioning requirements including waste removal and disposal, the Billingham-based Able UK Limited division is currently decommissioning six modules from Shell's Brent Delta platform, having already completed decommissioning of modules from the field's Bravo, Charlie and Cormorant platforms.

For Delta, as for all items received at its facilities, Able UK has applied its assessment process of best practical environmental option (BPEO) to determine the most beneficial reuse/recycling route. The drilling platform can be dismantled, with the derrick being recovered for transportation by road for onshore drilling operations. The helideck, living quarters and three process modules will all be assessed by the same BPEO method to establish whether they can be used in their existing form, refurbished or dismantled.

In the case of dismantling, the maximum parts possible are recovered for reuse elsewhere. Steel elements are transported to British Steel in Redcar to be recycled and the remaining minimum balance, including copper and plastic, is also recycled. In order to market specialist equipment, such as process modules, the company has engaged staff with oil industry backgrounds and a knowledge of the requirements of new build and conversion projects for which reuse equipment can be utilized.

According to chairman Peter Stephenson, Able UK aims to recover or recycle around 99% of a typical structure using the BPEO method, with the remaining 1% disposed of locally at the Group's owned and operated landfill site at Seaton Meadows. Even marine growth gets the recycling treatment and is used to break down heavy clay land which is abundant in the area.

Last year, Able UK decommissioned the Leman BK topsides and has now received the 1,000-ton, 46-meter high jacket. Stephenson believes that the offshore industry needs to review its decommissioning practices, in that the amount of cleaning of redundant equipment carried out offshore could be drastically reduced by transferring the operation onshore, thus improving the BPEO. "With our specialist knowledge of dealing with contaminated equipment we can recycle and dispose of waste material much more cost effectively and in less hazardous conditions."

Able UK believes there is a shortfall in quayside frontage in the Tyne/Tees area and, in response, is progressing rapidly its Teesside Environmental Reclamation & Recycling Centre (TERRC) development located close to the mouth of the river Tees. In addition to the company's own decommissioning activities, the 126-acre site has a 24.7 acre multi-purpose flooded basin/dry dock facility which Able plans to rent or lease to offshore-related fabrication companies. The basin can be used for a number of activities and is suitable for fabricating or converting a variety of offshore structures such as gravity based structures, jackets and FPSOs.

Other facilities planned for TERRC include a spool base site designed to handle 1-km pipe lengths, an offshore supply base, and a specially constructed facility to receive contaminated oil cuttings. "With regulations relating to dredgings and drill cuttings getting more stringent, we reclaim the maximum possible amount and dispose of the small balance at our special landfill site," says Stephenson.

Swan dissecting K10 structures

Newcastle-based Swan Hunter is another company active in the abandonment field. The company has established a special division, complete with its own facilities, to manage all decommissioning projects and a new heavy duty quay has been constructed over two berths capable of withstanding loads of 10 tons per sq meter.

This, coupled with a 180-ton crane, allows decommissioning to be carried out on several split units at the same time. Swan Hunter aims to recycle 99.8% of all material recovered from such projects.

Last year, the company completed the decommissioning and disposal of t he Viking A platform for Conoco. The jackets and topsides were transported ashore for disposal and either reused or recycled, with only 0.2% of the total tonnage disposed of in special landfill sites. This material consisted of LSA scale, wood, asbestos, mineral wools, plastics and rubber. Items recycled or reused included tubulars, plates and beams, pressure vessels, pumps and rotating equipment, power generation equipment, life boats and marine items, valves and wellhead equipment and living accommodation units.

Swan Hunter is currently working on dismantling the K10 and K13 jackets and topsides from the Wintershall Field for Seaway Heavy Lifting and is shortly due to start work on a small 70-ton subsea protection cover for NAM.

Like Able UK, Swan Hunter has utilized decommissioned items to enhance its own facilities, constructing a new load out/load in quay from dismantled equipment which was completed in May this year.

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