DISCOVER Magazine #7

A gem of a project. De Beers’ record-breaking commission

Published in category: Offshore Wind
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Michael CurtisMichael Curtis
Project head
De Beers Marine

When it comes to diamonds, De Beers Group is a household name, famed for the scale of its operation and its ubiquity in the market. De Beers has been around since 1888 and has principally been concerned with extracting diamond resources from onshore mines in several countries on the African continent.

From the early 1990s, De Beers began to complement its onshore mining operations by moving into offshore diamond recovery as well, as technology made the practice more cost-effective. De Beers expanded its offshore diamond mining operations in Namibia and in 2000 established Debmarine Namibia in partnership with the Namibian Government. Debmarine Namibia has been growing production from its fleet of offshore mining vessels ever since. More recently, technological development allowed a technique known as sub-sea crawling to come to prominence, thanks to its operational efficiency.

In 2018, the success of De Beers’ offshore operation led to demand for a new additional mining vessel (AMV) to bolster the capacity of its fleet. Following a rigorous tender process, De Beers chose to partner with Damen Shipyards Group on construction of the new vessel, and steel cutting began at Damen’s Mangalia yard in May 2019. Damen is one piece in a large and complex puzzle, as Michael Curtis, project head for De Beers Marine, explains.

“This was a relatively large tender, encompassing many specific criteria,” says Michael. “Due to our confidence in demand, we need a high-quality vessel we can rely on for at least the next 30 years. Furthermore, this is an integrated project involving numerous partners, and each component must be delivered on time, so we need to be confident we can rely on every partner we choose.”

Recovering diamonds offshore is not a common practice, so the preparation of vessels for such a specific purpose is a collaboration between marine experts and mining experts. “The shipbuilder provides the vessel,” says Michael, “and De Beers fits the specialised mission equipment. Most of the design and assembly of mission equipment is done by De Beers in Cape Town, with some external providers supplying additional equipment. It all needs to be integrated into the delivered vessel.” In the case of the AMV3 vessel from Damen, Michael explains, “We’re managing multiple parallel streams that come together simultaneously in 2021, so the vessel needs to be delivered on time to avoid delaying the equipment fitting and incurring extra costs.”

Historically, De Beers has prepared its vessels by purchasing existing ships and refitting them for the purpose of operation. De Beers’ certainty in the longevity of Namibia’s offshore diamond resources means it is in a position to commission more of a purpose-built vessel. The first example of this was the SS Nujoma, the first newbuild commissioned by De Beers, which was constructed by Norwegian firm Kleven and delivered in 2017 for sampling operations.

Like the Nujoma, the AMV3 vessel will be built on a Marin Teknikk design – another critical factor in the process. De Beers likes making long-lasting successful partnerships but wasn’t complacent in consideration of the design bids. “We didn’t choose this design lightly,” says Michael. “It’s especially important on these complex ships, as there is no surplus space – the design is paramount to the success of the project. For example, we’re very happy with the performance of the SS Nujoma: it has a great sea-keeping capability, low fuel consumption, good crew comfort and good station keeping.”

The project breaks new ground in more ways than one – at 177 metres long, the AMV3 will be the largest diamond mining ship in the world, three metres longer than Debmarine’s current largest vessel, the Mafuta. “Vessel size plays a role in the technology we can use on board. Crawler vessels are larger than drill vessels because their production rate is higher and they need to carry a bigger processing plant,” says Michael.

The Mafuta - Marin teknikk-render

Drilling operates on a microcycle consisting of a short drill time followed by an almost equal move time. This technique leads to high periods of inactivity, but it was still the most effective method of marine mining up until relatively recently. Sub-sea crawling became successful in the mid 2000s, as the technology matured enough for vessels to operate efficiently.

The Mafuta, itself a crawler vessel, began recovering diamonds in South African waters in 2007, moving to Namibia in 2010. In crawling, a nozzle is used to suck material off the sea bed, aided by a slewing mechanism that loads material into the nozzle, meaning that the overall mining rate and recovery efficiency is higher. Sub-sea crawling is now the solution of choice, providing higher production rates than drilling, and a larger part of Namibia’s offshore diamond area is economically viable with crawler technology.

The AMV3 will also be the most technologically advanced marine diamond recovery vessel in the world and will feature a dynamic positioning system (DP2) based on a seven-thruster propulsion system powered by six generators. Michael believes that now is the time dynamic positioning has come into its own. “Historically, we’ve always used vessels with a 4-point mooring spread – the stability was always there but it takes a day to lift, meaning we lose a production day every seven to eight days.” Now, DP technology surpasses anchoring and offers a much greater degree of flexibility. “With DP,” says Michael, “we’re not limited to the size of spread, there’s no risk of anchor loss, we don’t have to carry and maintain anchors and winches, and there’s no safety risk in the handling of anchors.” Moreover, DP requires very little increase in fuel consumption to keep the vessel on its station, so the benefits make it a far more attractive proposition.

Given its design specifications, the AMV3 is the subject of high expectations. “Performance is key,” says Michael. “This vessel will contribute 30% of the total production of the Debmarine Namibia fleet, so uptime is very important. Given its size and technological superiority, this vessel will be the ‘flagship of the fleet’ for now.” The AMV3 design meets high environmental standards and has a green passport. It burns cleaner fuel, producing reduced rates of SOx and carbon emissions, leaving a smaller environmental footprint and requiring less energy and people to recover diamonds from the same area of sea bed.

Longevity is also a critical component of the design and construction. As diamond recovery and technology change over time, it’s important for De Beers Marine Namibia to be able to maintain the vessel and keep it in good condition so it can meet the changing demand. As Michael reflects, “We know that Damen builds high quality vessels to last decades, which is exactly what we need. A bad ship is always a bad ship: you can’t patch it up, you have to start again from scratch. We’ve seen that the quality of ships produced by Damen in its Galati yard is very high, and we know that Mangalia has a world-class steel making capability, so our expectations of this project are high.”

The strategic purpose of this order is primarily that of fleet expansion, but also of regeneration. Debmarine’s existing production assets are quite old and will start retiring over the coming decade.

As the older drill technology is phased out,” Michael explains, “we’re also expanding our production by increasing our crawler capability.

Now is the perfect time: there’s a bright future for diamonds in Namibia, according to Michael. “The country has a great resource,” he says. “The diamonds mine at 98% gem quality, some of the highest value diamonds in the world.” For the country as a whole, this project plays an important role, providing high numbers of sustainable jobs for local workers. “It’s a massive social uplifter,” says Michael, “and I’m very proud to be associated with the project, it’s unique and exciting. The future looks very positive.”

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