Continuous improvement of the return air-raise-silencer system at Totten Mine

ABSTRACT

The Totten Mine return-air raise was designed with two parallel fans equipped with silencers to reduce the noise emitted from the outlets to the environs. As the development and production of the mine progressed, the silencer system needed to be upgraded. Additional maintenance strategies have been necessary to meet the regulatory noise limits enforced by the Province of Ontario. The current mine plan required the fans to reach the upper limit of their capacity by the first quarter 2019. To achieve this operational target, additional silencing capability was required. Within the current constraints at the mine site, Totten Mine explored alternatives to extend the noise silencing capacity, including a new silencer baffle design and a new layout that allowed doubling the length of the silencer system. Using acoustical measurement data collected on several occasions, this article presents and discusses the performance of the various silencing systems that have been installed on the return air fans at Totten Mine.

RÉSUMÉ

La remontée d’air de retour de la mine Totten a été conçue avec deux ventilateurs parallèles équipés d’un système de silencieux afin de réduire le bruit émis par les sorties vers les environs. Au fur et à mesure du développement et de la production de la mine, le système de silencieux a dû être amélioré. D’autres stratégies d’entretien ont été nécessaires pour le respect des limites de bruit réglementaires appliquées par la province de l’Ontario. Le plan minier actuel exigeait que les ventilateurs atteignent la limite supérieure de leur capacité d’ici le premier trimestre de 2019. Pour atteindre cet objectif opérationnel, une capacité de coupure supplémentaire était nécessaire. Dans le cadre des contraintes actuelles sur le site de la mine, la mine Totten a exploré des solutions de rechange pour augmenter la capacité de réduction du bruit, y compris un nouveau concept de déflecteur de silencieux et un nouvel aménagement qui a permis de doubler la longueur du système de silencieux. À l’aide de données de mesure acoustique recueillies à plusieurs reprises, cet article présente et discute les performances des différents systèmes de silencieux installés sur les ventilateurs de retour à la mine Totten.

KEYWORDS:

• Axial fans
• Return-air raise (RAR)
• Silencer system

MOTS CLÉS:

• élévation de l’air de retour (EAR)
• système de silencieux
• ventilateurs axiaux

Additional information

Notes on contributors

A. Dobson

A. Dobson is a senior acoustical consultant at HGC Engineering. He has worked extensively in the mining sector to complete Acoustic Assessments, feasibility studies and the noise control design, to support the regulatory and permitting requirements for noise. This work draws upon 13 years expertise with specialty measurement procedures, including sound intensity methods, and the use of CadnaA modeling software. [email protected]

C. Allen

C. Allen has held various mining engineering positions in Canada and the USA over the past 30+ years and currently holds the role of Manager Ventilation Design & Tech Support for Vale North Atlantic Operations. She has published in the areas of technology, design, health & safety and numerous speaking events; as well as involvement on research, boards, standards and legislative committees.

E. Acuña

E. Acuña is a former Totten Mine Ventilation Supervisor and is currently part of the NRCan-CanmetMINING team in Sudbury, Ontario. With over 50 published technical articles, his mining experience includes continuous improvement, applied optimization, ventilation control systems, ventilation network design, modeling and surveying, noise mitigation, estimate of heat loads, heaters and cooling for mechanical and natural systems, research, mentoring, training, and consulting.