All set for demolition of Delimara chimney this summer

27.05.2017

Enemalta will start dismantling the chimney of Delimara 1, the last-remaining heavy fuel oil plant at Marsaxlokk, this summer.

The Company has completed the required plans and preparatory work to dismantle this 150-metre chimney, the highest structure in the Maltese Islands, whilst ensuring the safety and security of the other power plants in operation nearby. Specialised equipment for the dismantling of high structures is being shipped to Malta for this purpose. The Italian contractors working with Enemalta in this project were shortlisted in December, following an international call for tenders.

Earlier this year Enemalta started receiving electricity through the new gas-fired Delimara 4 plant and the Delimara 3 engines, which were rebuilt to run on natural gas instead of heavy fuel oil. Soon after, the Company started reducing the use of the 1992 Delimara 1 plant, the oldest one at the Delimara Power Station, paving the way for its decommissioning and dismantling. The plant was switched off on 24th April, the last day that Malta used heavy fuel oil for electricity generation.

At the same time, the Company’s architects and engineers were collaborating with the contractors and with the authorities, to finalise the plans to dismantle it. The Delimara 1 includes two heavy fuel oil fired boilers, two 60 MW steam turbines, the concrete and steel chimney and other auxiliary equipment.

The chimney structure comprises a cylindrical concrete shield rising up more than 50 storeys, with a base diameter of 12 metres. The concrete walls are two metres thick at the bottom and 60 centimetres on top. Inside the concrete structure there are two 2.3 metre steel exhaust pipes that emit the smoke produced by the oil-fired boilers.

The dismantling process will start with the lowering of these two steel pipes and all metal structures inside the chimney, using strand jacks, so that they can be dismantled on the ground. To demolish the outer structure, the contractors will erect an auto-lifting platform on five steel columns all the way to the top. Remote-controlled demolition robots on top of this platform will then be used to demolish the first 1.5 metres of the concrete walls. The platform will then be lowered 1.5 metres for the demolition robots to continue the demolition. This process will be repeated approximately 80 times until the chimney is lowered to 35 metres. At this point, the platform will be dismantled and the remaining part of the stack will be demolished using a high reach demolition excavator from ground level.

All works are being coordinated in collaboration with the relevant environment and occupational health and safety authorities. The materials of the structures, including metals and construction waste, will be transported from the site and processed using sustainable methods. Where possible, these materials will be recycled.

Ing. Fredrick Azzopardi, Enemalta plc Executive Chairman, explained that now that the dismantling of the Marsa Power Station is nearing its final stages, the Company is focusing on the Delimara 1, the last remaining heavy fuel oil fired plant in Malta.

“Our priority in this project is to make sure that all structures are removed in the safest way possible, without putting at risk the wellbeing of nearby residents and of all the workers at the power station. This dismantling project is the final chapter in the history of heavy fuel oil in Malta, as all our electricity requirements are now being met through more efficient sources, with minimal impact on our environment.”