The Asia Miner

SEP-OCT 2014

The ASIA Miner - Reporting Important Issues to Mining Companies in the Asia Pacific Region

Issue link:

Contents of this Issue


Page 65 of 91

64 | ASIA Miner | September/October 2014 WHERE there's smoke, there's fre, but when it's only smouldering it can be hard to detect. A Melbourne technology company is monitoring mines around the world for the earliest signs of fre. Xtralis's Very Early Smoke Detection Apparatus, or VESDA, can save lives and property. The concept behind VESDA started in the 1970s when the CSIRO was asked to evaluate fre detectors for telephone exchanges. None of the equipment performed as well as their own test instrument which was previously used to monitor bushfres. The device they built from it was so sen- sitive that industry was initially reluctant to get involved, due to a fear of false alarms. But eventually IEI Pty Ltd – later to become Xtralis – succeeded in mak- ing a small, cheap detector that was quickly adopted in Victoria. VESDA is an Air-Sampling Smoke Detec- tor (ASD) and works by actively breathing in air, rather than waiting for smoke to waft up to it. Larger dust molecules are then fl- tered out and a laser is used to detect the smoke particles. Variable alarm levels mean that it can be set to warn of a fre that is merely smouldering, long before it bursts into fame, thus buying time for early verifcation and response. As the pioneer of this technology, Xtralis is now one of the world's leading manufactur- ers of ASD systems, with global offces and a branch still based in Victoria. Their VESDA Laser Industrial and ECO gas detector products are specially designed for harsh environments and are used in mines in Australia, South Africa and Noumea while in Alberta, Canada, Suncor Energy uses VESDA to prevent fres at its huge, open-cut oil-sand mines. Dr Peter Meikle from Xtralis says, "We've combined our technological expertise and 25-plus years of industrial feld experience to provide very early warning smoke detection for the most challenging environments." AUSTRALIA'S mining and quarrying regions are an indicator for the in- dustry on a global level, where pressures to achieve greater resources processing rates have unearthed a hidden risk for company owners and managers. Situations are occurring where a processing plant is pushed to maximum capacity for the frst time, and these are unchar- tered waters for site owners that have never tested their technologies at that high level or beyond the plant' nameplate capacity. Engineering and design company Soto Consulting, which is at the forefront of plant analysis and capacity evaluation, says the digital sim- ulation environment is the ideal test platform for plant owners and man- agers to foresee any complications. "The fastest and most accurate approach is to review operational lim- itations of their plant using digital simulation means – not just old plants but also new ones which are constructed with conficting performance requirements to that originally planned during the design specifcation phase for the plant," says managing director Frank Soto. "As a rather common example, mine processing plant owners are aiming for a demanding a 14,000 tonnes/hour of their conveyor sys- tems, which is a very fast rate and will almost certainly lead to new operational and maintenance issues that will impact on the operating cost of the plant. "Pressures to increase rates are also taking existing plants into ex- tra periods between shutdowns in operations, which extends the time frames between scheduled repair sessions. But perhaps the biggest cause for concern is that many plants are being tested under actual operating conditions with a high level of trial and error, taking guesses as to which parts may or may not work under the untested, increased workload. "Our reasoning is that it is best to review a plant and assess it properly in the digital simulation environment before exposing it to a potentially crippling risk by taking chances 'on the fy'. We have proven digital testing and prototyping methods and we can work out if we will get the additional uptime, throughput and capacity they are chasing." Soto Consulting believes this approach is a form of operational ex- penditure which optimizes a mine's capital expenditure. Using rapid prototyping and simulations, it enables identifcation of areas where modifcations to an existing plant can increase throughput, reliability and maintainability. "Sometimes this approach even unearths safety issues which should have been embedded in design but generally aren't, therefore improv- ing access and safety for employees," Frank Soto says. "As many plants reach their maximum operating capacity and now start to go beyond the original specifcations the risk is that plants start to fail and breakdown prematurely. The peak performance and through- put may be negated due to extended breakdowns and outages that re- duces overall plant throughput and increases operational expenditure." Problems of exceeding plant capacity Detecting smoke before the fames A fre growth chart indicating the early detection capabilities of an Xtralis Very Early Smoke Detection Apparatus.

Articles in this issue

Archives of this issue

view archives of The Asia Miner - SEP-OCT 2014