Expert Process Solutions is the new branding slogan for XPS. Dominic Fragomeni, Director, XPS, told IM, “we are excited about this change and believe it is very appropriate in describing the level of expertise that we provide to our clients. Many of our managers, principals, engineers, technicians and technologists are considered ‘expert’ in their field. This expertise is a combination of practical experience and technical knowledge. During lean economic times with low availability of capital it is essential that the operating plants optimise use of installed infrastructure and equipment to maximise revenue and reduce unit costs.
“This is where XPS expertise has played a major role, for example, by performing QEMSCAN analysis on concentrator samples to determine the financial value of the grade and recovery improvements.”
XPS can define sampling, sample preparation requirements and perform the detailed data analysis required to prioritise and maximise value. In addition, XPS has provided mine and plant support in implementation of best practice process control solutions. It is quite common for many control systems to be underutilised, and XPS has the expertise to ensure control loops are running in automatic for robust regulatory control to implementing advanced strategies to maximise financial value of the asset.
The Materials Technology group has provided specification of materials to new equipment, oversight during equipment fabrication and diagnosis of failures to prevent reoccurrence. “Our Extractive group have some of the most innovative minds in the industry and have contributed to new process developments in pyro and hydrometallurgy and also have solid plant operational expertise.
“In addition to operations support, any new greenfield projects must be resourced to target a ‘Type 1 start-up’. We have achieved this with our support to the Eagle mine start-up.”
As reported in the spring 2014 edition of the XPS Bulletin, 2014 represented a significant milestone for Michigan’s Upper Peninsula with the commissioning of Lundin Mining’s Eagle mine.
It consists of the Eagle underground mine, located approximately 55 km northwest of Marquette, Michigan, USA and the Humboldt mill, located 45 km west of Marquette in Champion, Michigan. The mine and mill were commissioned in the third quarter of 2014, with concentrate production commencing at the end of September 2014. The mine is expected to produce an average of 17,000 t/y each of nickel and copper over the current mine life of eight years at an average cash cost of $2.50/lb of nickel.
XPS’ history with the Eagle mine dates back some years, when a former owner contracted XPS to develop toll milling options for the ore. Lundin’s decision to refurbish the nearby Humboldt Mill in Marquette County resulted in a new round of flowsheet confirmation and piloting, in which XPS was happy to participate. XPS completed batch testing and a mini flotation pilot plant where 12 kg/h of ore were continuously processed and bulk concentrate of over 22% Cu+Ni was produced. XPS succeeded in fully meeting the project objectives within a day and a half from startup, and was able, over the four day pilot campaign, to test and stabilise two flowsheet alternatives above and beyond client expectations. The bulk piloting campaign was followed by a Cu-Ni separation campaign using accumulated concentrate, in which samples of final Ni and Cu concentrates were produced for testing and marketing evaluation.
The XPS contribution to the start-up did not end at lab and pilot testing. In early September, Senior XPS Consultant Gord Marrs, former Director with Glencore Ni Sudbury Ni operations along with Tony Deng, Project Metallurgist worked along-side the Chief Metallurgist Darby Stacey and the Lundin team to start up and process commission the grinding circuits and flotation plant. Early commissioning was on low grade waste. Process stability was achieved and the feed then transitioned to more typical ore grades. XPS value contribution spanned many areas, including crushing plant operation/maintenance practices, grinding circuit stabilization/power distribution and meeting grind size targets. XPS’ expert knowledge in Ni flotation was recognized early from the mini-pilot plant and was used extensively to commission and stabilize the flotation plant. Along with providing direction, XPS was able to pass along key process knowledge either when on site or remotely. XPS continued to assist in the performance of daily plant balances and has responded to ‘911’ calls when the plant personnel requested assistance.
The commissioning results were excellent. On September 23, 2014, the Eagle project officially announced the handover of the facility to the operations team and the commencement of ramp up to design production throughput of 2,000 t/d. This target is expected to be achieved during the second quarter of 2015 or sooner. By month end September 2014, 3,000 t of Ni concentrate and 1,000 t of Cu concentrate were produced with concentrate grades and recovery curves improving during the month and will continue to be a focus during the ramp up period. XPS is playing a key role in achieving metallurgical grade and recovery targets. Performance to date is in-line with expectations and Eagle remains on track to meet, or exceed, market guidance on metal production. Project safety performance has been a great success with the project passing 1 million man hours without a lost time injury. The first shipments of saleable concentrate took place during October 2014.
The project has been delivered ahead of schedule and is expected to be at or below the budget of $400 million established at the time of acquisition in July 2013. Total spent since that time is $321 million, of which $96 million was spent in the third quarter of 2014. There will be ongoing ancillary project completion activities throughout the remainder of the year.
