This paper presents a success story in which diligent engineering design and equipment selection has produced a successful temporary spot cooling installation to support underground shaft sinking that has been in operation for the last 12 months. The need for cooling was apparent due to the depth of shaft sink (starting from >1,900m below surface), however this system was subject to many of the common challenges preventing the widespread use of spot cooling, including limited process water / dewatering capability, heat rejection equipment placement in the path of blasting fumes, limited air quantity for heat rejection, and layout constraints due to existing and upcoming mine services and construction.
Components were selected for mine duty with consideration for the dusty environment. Use of hybrid cooling towers allow for increased heat rejection capacity from evaporative cooling while maintaining a fully closed-loop condenser water circuit. Skid-mounting of all components allowed for easy placement and relocation. Use of HDPE piping lashed to existing ground support allowed for maximum layout flexibility and minimized installation time. Performance, operational features, and additional lessons learned, including feedback from operations personnel, will be shared.

The 4 Shaft Project represents a step change for ventilation capacity at Agnico Eagle's Macassa Mine in Kirkland Lake, Ontario. This paper outlines the process design, equipment selection, and experience in procuring new primary ventilation equipment for this project. Equipment includes new 64 MMBtu/hr natural gas direct fired mine air heaters with integrated silencers; twin 600 hp vane axial fresh air fans; and twin 3,000 hp centrifugal primary exhaust fans with demisters and high-performance silencing measures. This paper presents the description of obstacles tackled during the engineering design of the primary mine ventilation equipment, which included space limitations on surface and noise concerns due to proximity to local communities.

Lundin Mining operates the Eagle Mine in the Upper Peninsula of Michigan USA. The mine is preparing to construct the new Upper Keel zone – another high-grade nickel orebody in proximity to the existing mine. This paper provides an overview on several aspects of the ventilation design and strategy including the options for development and construction, life-of-mine operations, and the innovative ability for on-shift blasting during the construction phase while maintaining operations in the existing Eagle and Eagle East zones.

A stable and well-maintained mine ventilation system is the key to ensure a safe and healthy working environment for miners. A sudden, unplanned, and significant change in airflow termed as abnormal airflow is frequently observed in mine ventilation. Some abnormal airflows can return to normal without manual intervention, however, some abnormal airflows may cause catastrophic accidents if left unattended. In addition, abnormal airflow may be a consequence of an accident such as a blocked airflow route due to roof fall. Promptly diagnosing and locating the cause of abnormal airflow can help prevent accidents. Researchers at the National Institute for Occupational Safety and Health (NIOSH) have developed a method to diagnose the cause of abnormal airflow for underground mine ventilation systems. The purpose of this paper is to verify the developed method using experimental tests conducted at a NIOSH's experimental mine. The airflows were monitored by real-time atmospheric monitoring system installed in the experimental mine during the tests. The developed abnormal airflow diagnosing method, based on the resistance sensitivity and matching method, has been proven very reliable.