The Successful Development of the Detour Lake Grinding Circuit: From Testwork to Production

9 September, 2015 | White paper

Jorge Torrealba, P.Eng. Ph. D.

Director, Business Line – Mining optimization

icon linkedin


The Detour Lake gold mine is located 200 km northeast of Timmins, Ontario, Canada. In 2007, Detour Gold Corporation (DGC) initiated development activities on the Detour Lake project.

Early testwork was carried out to select the plant process design criteria and flowsheet. A PQ core size (85 mm diameter) was selected for grindability testwork. Two drilling campaigns collected 7,000 m of mineralized ore. A total of 8 DWT (drop weight test) and 146 SMC (SAG mill comminution) tests were conducted. The data was statistically analyzed to determine the process design values. Many values indicated extremely hard ore.

The grinding circuit proposed by BBA was a conventional SABC circuit with a tonnage of 55,000 mtpd at 95 microns with the addition of pre-crushing upstream of the SAG mill. DGC began commissioning the plant in October 2012 and first ore production began in January 2013 on Line 1, while commissioning continued on Line 2. Production on both lines started on March 2013 and commercial production was achieved September 2013. Production ramp-up continued through 2014 and design throughput (55,000 mtpd) was successfully reached in September 2014. Daily production rates have been tested to levels supporting the ultimate design of 61,000 mtpd and instantaneous hourly rates have also exceeded the 3,000 mtph level (both lines combined). Globally, these results provide confidence that the plant design was robust.

Note that this white paper was written in collaboration with Jacque McMullen and André Allaire from the BBA team and Jean-François Dupont and Ricardo Welyhorsky from Detour Gold Corporation.

To receive a copy, email us at


Stay connected and find out how BBA can help you maximize the value of innovation.