Shipping SeqiOlivine

By Jessica Roberts
Published: Friday, 22 May 2009

MINERALS ON THE MOVE: Since establishing the greenfield Seqi site in 2005, Minelco has emerged as one of the world’s select few olivine producers. Here IM examines Minelco’s navigation to markets through the untamed landscape of Greenland by Jessica Roberts, Assistant Editor

Swedish minerals group Minelco AS, part of LKAB, acquired 100% of the mining rights to the Seqi Olivine deposit, located in Seqinnersuusaaq, Fiskefjord, west Greenland, in June 2005, and wasted no time in preparing the site for mining.

Drilling machines, track excavators, and crushing equipment were all transported by sea to the greenfield Seqi site – around 90km north of Greenland’s capital, Nuuk – where Minelco and contractor MT Højgaard Grønland ApS had established a 340 metre long, 16 metre deep permanent pier.

The sea along the west coast of Greenland is normally ice-free, owing to the warming effect of the Gulf Stream. The water around the bay at Fiskefjord, however, has its own eccentric currents, and thus Minelco was restricted to developing the Seqi deposit during Greenland’s short summer season.

Minelco’s chief executive officer, Per-Erik Lindvall, said of the site development: “There is no official world record in how fast you can set up a mine in a true greenfield location, but if there was, I think that our performance in Seqi must be one of the fastest ever. The first equipment landed on the site in early July 2005 and the first ship left Seqi in December 2005 with 45,000 tonnes of olivine.”

Just over a year later, by August 2006, the necessary quay facilities had been installed and olivine production was running at full capacity of 1.1m. tpa. Minelco is the second largest producer of olivine globally (600-700,000 tonnes in 2008), with Norway’s North Cape Minerals AS leading the market (2.4m. tonnes in 2007).

 Flow chart production at Seqi
 


Mining

The Seqi olivine deposit is worked as an open pit mine. Typically, once the company geologist has located a suitable area, a Tamrock drill is used to drill around 100 holes, each 89mm in diameter and 12 metres deep. The cores recovered from the drilling are then examined at Minelco’s on site laboratory and the quality of the olivine is determined.

When all holes have been drilled, the rock is blasted using a mixture of dynamite and ammoniac nitrate fuel oil. Each blast yields approximately 15-20,000 tonnes of olivine ore in lumps ranging up to 800mm in size.

This material is then loaded by a track excavator - a Volvo EC 700 with a bucket capacity 3.8 m3 - on to Volvo A40 trucks, which transport the material 1.2km to the crushing plant. The plant, designed by Sandvik, is equipped with a hydrocone crusher and a jaw crusher, screening equipment and conveyor belts.

Here three fractions of olivine are produced (0-3mm, 3-10mm and 10-70mm) and the finished products are transported by a Volvo L350 loader, which has a capacity of 1,000 tph, to the storage area.

 Location of Minelco’s Seqi Olivine deposit
 


Finding fjords

Vessels entering and leaving the port at Fiskefjord need to pay attention to the special current conditions that occur in the narrow part of the fjord. These same currents also prevent the build up of winter ice.

Minelco’s port has several restrictions in place. It is capable of bearing vessels up to 200 metres long and 14 metres wide, and a tug is available to assist all ocean going vessels, however vessels may only navigate the fjord in daylight and only at a slack water period. High water at Seqi is in the range of 2-4.5 metres.

Vessels entering the port are loaded by a B&W mobile Samson feeder and conveyor. The loading berth has a length of 230 metres, and loading capacity is around 20,000 tpd.

From the port, Minelco ships its olivine primarily to Norway, with smaller shipments transported to the Netherlands, the UK and USA. This material is then processed according to customer requirements. The main markets for olivine include slag conditioning in steel furnaces, refractory bricks, EBT tap-hole filler, abrasives, and - increasingly - in CO2 sequestration.

The Seqi operation is staffed by around 30 employees, with the majority comprising native Greenlanders. Each worker has individual living quarters, which are equipped with entertainment facilities and exercise areas, and two cooks are available on site.

Minelco provides medical first aid at the Seqi campsite, and for serious injuries the company has an agreement with a rescue helicopter service based at Nuuk.

Weather conditions in Greenland are variable, with the summer months a relatively balmy 15°C, and the winter season reaching lows of –35°C. Production is stopped when temperatures fall below –20°C.

Acknowledgements: Lars-Göran Johansson, Greenland site manager, and Sofia Bergström, manager materials supply, Minelco AB, for logistical insight into Minelco’s Seqi Olivine operation.