Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr
Issue link: https://emj.epubxp.com/i/98266
TA I L I N G S Zulfiqar Ali, senior engineer–tailings planning at Suncor, described the TRO approach in a paper presented at the Tailings and Mine Waste 2011 conference held in Vancouver, B.C. The implementation of TRO is based on two primary technologies: mature fine tailings (MFT) drying; and sequential construction of sand dumps. MFT is the classification for fine clay particles, smaller than 44 microns, suspended in water; it is the most challenging component of oil sands tailings when it comes to finding solutions that accelerate particle settling time. In the TRO process, MFT is mixed with a polymer flocculent, then deposited in thin layers over sand beaches with shallow slopes. The eventual product is a dry material that is capable of being reclaimed in place or moved to another location for final reclamation. This drying process occurs over a matter of weeks, allowing for more rapid reclamation activities to occur. Under the TRO scheme, process tailings will be deposited into in-pit beach- ing areas enclosed by berm structures where sand will trap portions of the fine tailings while the remaining fines will be suspended in water in the form of thin fine tailings. The thin fine tailings will then be transferred to MFT settling ponds where they will receive a polymer additive in the MFT drying process. The tailings with polymer additive will then be deposited in thin layers over sloped beach areas, where freeze/thaw processes and the polymer treatment will then help recover a portion of the water, while the remaining water will evaporate or remain in the resulting deposit. The end result is a clay product that can be reclaimed in place or be placed in mine dumps. Suncor reportedly spent $250 million to develop the process and although it has, and will continue, to spend millions to construct the estimated 500–600 hectares of beaching areas needed for drying tailings, it figures it will save at least $1 billion over the next decade by using this approach to reduce its need for future conventional tailings ponds. Suncor has patented the TRO process and says it is willing to make the technology available to other interested parties—a step that hasn't yet taken place. "What we're [asking] is, we want to help recoup our R&D; costs," Suncor CEO Rick George told the Toronto Globe & Mail in a recent interview. "That's a reasonable request." Capping it Off Syncrude Canada, the largest oil sands producer, is moving ahead with several tailings management technologies, which include centrifugation of MFT and water capping among others. Syncrude plans to implement centrifuging technology in two stages: a first-stage, commercial-scale plant that, at last report, was scheduled to come online by the end of 2012, and a $1.9-billion full-scale plant that will start up in 2015. In November 2012, it awarded Houston, Texas, USA-based engineering company KBR two contracts to execute module fabrication and field construction for what it calls COMPANY PROFILE- PAID ADVERTISEMENT Eriez—Coal Processing Eriez' Mining features separation, material handling and detection systems to concentrate magnetic ores, recover coal fines, remove tramp metals, convey or feed heavy material as well as provide customers with a full service department. Metal Detectors Detects tramp and non-magnetic metals as small as ½". These metal detectors are built to handle harsh environments. Heavy Duty Feeders Low-horsepower, high-capacity mechanical feeders that can handle bulk materials in volumes up to 2,250 tph. Column Flotation • CoalPro™ Column Flotation Cells for high-volume recovery of fine coal (0.2 mm) particles. • StackCell™ offers column-like performance in a substantially smaller footprint than conventional cells. These compact, stackable units offer considerable savings for new installations and are ideal for expanding capacity in an existing plant. Wet Drum Separators Provide continuous, automatic recovery of magnetite or ferrosilicon in heavy media operations and/or concentration of ferrous and weakly magnetic ores. Five-Star Service Offers a 24/7 service hotline, original OEM parts, on-site field service, equipment remanufacturing and full "as new" warranties. For more information, visit www.eriez.com. Suspended Electromagnets Remove damaging tramp iron from conveyed materials. Available for use in hazardous, dusty and gassy locations. 62 E&MJ; • DECEMBER 2012 www.e-mj.com