Disposal of redundant equipment including STS & RTG cranes and miscellaneous equipment,

OPCSA or Operaciones Portuarias Canarias SA, owned by MSC, has been operating since 1986 and is the largest, most modern container terminal in the Canary Islands. The terminal is based in the port of Las Palmas in the north-east of Gran Canaria, Spain. OPCSA is directly connected with more than 74 ports around the world and lies on the busy shipping routes between Europe, Africa and South America. OPCSA consolidated itself as a point of reference after years of constant evolution, becoming a leading company in the loading/unloading sector, transforming the Port of Las Palmas into a logistics base for South-South and North-South connections.

Because of handling high volumes of containers, the next obvious development for OPCSA was to incorporate the use of automated solutions. OPCSA embarked on a process of renovation of the machinery, which initially saw some €2million euros invested to acquire new terminal tugs, trailers, empty handlers and reachstackers of the latest generation to improve efficiency. OPCSA will take a giant step in its modernisation plan with the arrival of two MegaMax STS Quay Cranes, the largest in the market due to their size and capacity.

The OPCSA terminal equipment renewal project was to begin with the demolition of the Paceco Crane OPCP01, which was retired after 25 years of activity. Specifically, OPCP01 was the first QC to be installed in the OPCSA terminal and has made a total of 1,176,233 movements cycles during the 59,742 hours in which it had been operational.

For the disposal of STS OPCP01, OPCSA’s own engineers analysed two of the most common method for carrying out this type of operation, they took into consideration; compliance with all the safety regulations, reduction and elimination of risk, all the while minimising disruption to the intense terminal operation. The first of these is a piecemeal dismantling operation utilising an auxiliary crane, and the second option was a Controlled Collapse.

It was considered that the first option entailed significantly more unnecessary risks, so the second option was the obvious choice. The OPCSA’s engineers also determined that the force generated by the impact of the crane on the quay deck will be 55% less than the force generated by one wheel of the 80-tonne container lifting machines that operate in the terminal. This was considerably less than anticipated loads that a heavy lift mobile crane would impose during a piecemeal dismantling.

OPCSA then conducted a robust round of due diligence to select a suitable contractor for the demolition of STS OPCP01 along with the disposal of 4 RTG cranes, 14no. terminal tractors, 16no. terminal trailers, 1no. reach stacker and other miscellaneous equipment. Following the due diligence, OPCSA were clear that only one contractor possessed the required specialist knowledge, skill, experience, track record and resources to carry out the works in accordance with the strict project specification. Therefore, O’Brien Specialist Crane Services was awarded the contract for the OPCSA redundant equipment disposal project.

Following the awarding of the contract O’Brien Specialist Crane Services immediately started works on the planning for the project which saw a full engineering and environmental study carried out to determine a safe and sustainable method of disposal. O’Brien Specialist Crane Services proposed a controlled collapse method for the demolition of the STS and RTG cranes, which centred on the creation of pin hinge points around the portal structure which allows the cranes to fold down to ground level in a controlled manner. The PACECO STS crane had previously been heightened, and as a result there had been a number of additional bracing members installed within the portal structure. This posed an additional challenge to the O’Brien SCS engineers to determine a solution to deal with this. The solution was to design and install temporary restraints to control the bracing during the collapse.

As set out by OPCSA, minimising disruption to terminal operations was crucial, especially to vital quay side operations. As a result, OPCSA set a stringent deadline of only 3 days to open the STS crane rails following the controlled collapse of OPCP01 to allow full vessel berthing capacity. Despite this target being very ambitious, the O’Brien SCS site team would ultimately reopen the 30m crane rails within only 1 day following the controlled collapse.

The prevention of damage during the demolition was of the utmost importance, so the engineers from O’Brien Specialist Cranes Services carried out an individual ground impact assessment on each of the cranes taking into account the weight of the structure, height of the pin hinge points and fall path of the crane. From this the engineers were able to determine the rate of acceleration, fall velocity and impact force onto the quay deck. From the ground impact assessments, a bespoke sand quay deck protection plan was designed and implemented to absorb the energy of the impact allowing us to achieve a ground bearing pressure of only 70.8kN/m² resulting from the controlled collapse of the 80-metre-tall STS structure. The same process and procedure was carried out for each of the four RTG cranes. To further reassure all stakeholders, an independent ground impact monitoring specialist was appointed to measure, record, and produce a detailed report of the ground impact and vibration sustained to the quay deck during the controlled collapse. This report was conclusive and determined that the impact of the STS crane was as expected and well within all quay deck limitations.

Following the planning stage, O’Brien SCS mobilised to Las Palmas, shipping specialist equipment from the UK which was not available locally in Gran Canaria.

OPCSA identified an area where the scrap processing of all equipment could take place while limiting disruption to operations, however, this area was of a very confined size. Therefore, the project was split into two separate phases, the first being the demolition and disposal of STS OPCP01, followed by the disposal of all other equipment. Unfortunately, the RTG cranes were spread across 4 different locations within the 55 hectare terminal, and due to operational constraints, it was not possible to dispose of the equipment in these locations. In addition, these RTG’s were in an inoperable condition, meaning these could not be relocated within the terminal. The solution developed by the O’Brien SCS site team was to carry out the controlled collapse of the RTG’s in their current location at a time when there was a lull in terminal activity, and then following the demolition moving the RTG’s in sections to the main scrap processing area. This operation took a total duration of only 6 hours for the onsite team per RTG.

Once at ground level specialist mechanical equipment was used to process all ferrous and non-ferrous metals for recycling, this allowed the team to clear the site in as quick a time as possible, some 2 weeks ahead of schedule. The project achieved a >99% recycling rate with a 100% non-hazardous waste diversion from landfill. The project featured many risks including working at heights, structural pre-weakening, operation of heavy plant, working in a live port, and working over/near water. However, the project was seamlessly completed to the total satisfaction of OPCSA, the Las Palmas Port Authority and other key stakeholders, with zero health, safety, or environmental incidents.

The O’Brien SCS team carried out all aspects of this project in-house including;

• Initial site survey & feasibility study,
• Provision of a ground impact study,
• Designing of STS and RTG controlled collapse procedure,
• Stability and C of G calculations for each stage of the pre-weakening operation,
• Design & installation of quay deck protection,
• Design & installation of temporary bracing systems,
• Provision of risk analysis,
• Implementation of environmental control measures,
• All onsite workings required to demolish and dispose of all redundant equipment,
• Planning, supervision and execution of all works,