Decommissioning has recently become an increasingly significant issue in the petroleum sector.
One of the greatest challenges facing the industry is the decommissioning of existing infrastructure. Owners of oil and gas facilities have a duty of care which enforces the responsible handling of infrastructure from construction to final disposal.
As operators continue to gain understanding of the importance of the end-of-life of these developments, the issues surrounding decommissioning are being acknowledged and progressively assessed.
Furthermore, being conscious of the complexities involved in the decommissioning of assets is of high importance for all parties taking part in these types of works.
Liberty Industrial Director Clinton Dick says that utilising an experienced specialist industrial demolition and remediation contractor like Liberty Industrial can play a major role in the success of the project to ensure hazardous assets are decommissioned, deconstructed and remediated following stringent safety procedures and environmental controls.
Image: The Clyde Refinery.
Liberty Industrial has successfully and safely removed some of Australia’s largest and most complex major hazard facilities in the petroleum, mining and power generation industries.
Using innovative methodology and technology, Liberty Industrial has demolished entire refinery facilities such as the Shell Clyde Refinery, which had previously been used for refining operations and is now in the process of being converted into a terminal facility.
The first phase of the works involved demolition and removal of all redundant refinery infrastructure including refinery processing units, plant and pipework, chimney stacks, storage tanks and buildings.
One of the most significant structures demolished was the 60 metre tall 1000 tonne Platformer Reactor structure. The method used for demolition was a predetermined mechanically induced collapse. A carefully designed and calculated structural pre weakening was undertaken with a 120-tonne excavator to perform a controlled demolition.
An even bigger structure demolished was the 65 metre tall, 1,500-tonne Reactor and Stripper structure. Controlled explosive techniques fragmented four of the structure’s seven reinforced concrete foundations, which forced the structure to hinge over the remaining supports and collapse.
Prior to these works commencing, Liberty Industrial used 3D simulation software to demonstrate the proposed demolition methodology to key regulatory stakeholders to ensure it could be demolished in a controlled manner.
Five 80-100 metre high reinforced concrete chimney stacks, each weighing 1000 tonnes, were also demolished through the controlled use of explosives.
Liberty Industrial’s works on this project saw them becoming a finalist in the Contract of the Year over US$1 million category at the World Demolition Awards.
Liberty Industrial recently returned to work at the site to carry out the second phase of demolition works in December 2019. Works is expected to be carried out over five months, with the project’s completion date set for May 2020.
Works involves the demolition of redundant terminal infrastructure such as liquid petroleum gas spheres, the LPG loading gantry and 29 large storage tanks.
Clinton says the project is exceedingly complex as works need to progress in live operation areas.
“The demolition of the LPG spheres, LPG loading gantry and tanks has to undergo precise forward planning, ongoing daily gas testing for lower explosive limits and constant fire watch and spotters to prevent fire.”
Another project delivered by Liberty Industrial involved the demolition of Exxon Mobil’s entire Port Stanvac Oil Refinery, located off the Gulf St Vincent in South Australia.
The project involved the demolition of the refinery process plant and piping, storage tanks, chimney stack, flare stacks and other associated above-ground facilities. It also included removal of all the pipework and other oil handling facilities located on the wharf structure.
It became a benchmark project as an entire refinery demolition project had never been attempted before, paving the way for subsequent projects.
Clinton says one of Exxon Mobil’s main concerns was the impact on the surrounding coastline which was a key factor when they developed their demolition strategy.
“We had to take the sensitive location of the refinery carefully into account to ensure there were no environmental effects as a result of the removal of the refinery.”
Liberty Industrial used mechanical methods including an arsenal of excavators ranging from 36 to 120t, with state-of-the-art demolition attachments.
Liberty Industrial also recently carried out the removal of a section of redundant infrastructure at the former BP Bulwer Island fuel refinery near Brisbane. The works involved the removal of the bitumen plant infrastructure and the induced collapse demolition of an 87m Flare Stack.
