EXPLOSIVES AND BLASTING_proof 18/07/2016 14:25 Page 3
EXPLOSIVES AND BLASTING
Examples of the different density variations that
were used at the mine during the trial
using Dyno Nobel’s Differential Energy (ΔΕ)
technology. The goal was to improve safety,
particularly through NOX reduction, along with
improving blast performance with fragmentation,
oversize and hard toes. Dyno states: “By
switching to Differential Energy the mine met
every goal they set out to accomplish, which
resulted in lowering their overall production
costs.”
To help address the problems the mine was
having, Dyno Nobel employed its Titan 1000ΔΕ
technology. Prior to the trial, the mine was
loading dry holes with a 30/70 mixture (30%
emulsion and 70% ANFO) and wet holes with
100% gassed emulsion. The Dyno Nobel
Differential Energy system allows blasters to
accurately vary the density of chemically gassed
emulsion as it is being loaded into the blast hole,
enabling the operator to load multiple densities
of gassed emulsion into the same hole and
match the geology characteristics of the ground.
The mine had the challenge of blasting
through a variety of different geologies from very
hard rock to softer rock. Due to this, the blast
crew loaded very high densities in the hard rock
and much lower densities in the softer rock to
maximise the efficiency of the blast. The attached
figures illustrate the different density variations
and the measured results of detonation velocity
(VOD) from one of the blasts.
The trial period was extended from three
months to six months during which over 109 trial
blasts were conducted to adequately measure air
quality, mine productivity, fragmentation and
diggability. Dyno states that the mine was able to
meet the following goals set forth at the
beginning of the trial:
n Safety: Differential Energy proved to be a
reliable and resilient product that provided
dependable results where no undetonated
blasting agent was found in the muck piles
n Air Quality: The number and severity of NOx
incidents were significantly reduced. This
allowed the mine to consider revising its air
quality permit to allow for larger blast events
Results of detonation velocity measurements for one of the blasts
58 International Mining | AUGUST 2016
n Productivity: Switching to Differential Energy
allowed the mine to go from using two bulk
trucks to a single truck that can load both wet
and dry holes. The Differential Energy truck
provided a faster turnaround time and a
larger capacity allowing for more holes to be
loaded per cycle
n Fragmentation and Diggability: Oversized and
floor grade problems were noticeably
reduced. There were no physical
measurements of fragmentation, but drill and
blast managers and shovel operators
observed a noticeable improvement in dig
times.
Since the trial (now over a year later), Dyno
says the mine has fully adopted Differential
Energy technology, using 100% Titan 1000ΔΕ and
no longer uses ANFO. Dyno Nobel’s Differential
Energy technology enabled the mine to
redistribute the explosive energy in the blast
hole, distributing the accurate amount of energy
throughout the hole, varying the detonation
pressure. This process reduced NOx, improved
fragmentation, reduced oversize and hard toes
and increased productivity while reducing overall
costs.
MAXAM increases influence in
Australia
As part of a broad tender for services and
products, MAXAM Australia was recently selected
as the sole provider of blasting solutions for Mt
Carlton and Cowal gold mines, both managed by
Evolution Mining, now Australia’s second biggest
gold producer.
Mt Carlton, located approximately 130 km
south of Townsville on the north-east coast of
Australia, comprises two open pit zones: the
main large gold dominant deposit and the
smaller silver rich deposit. In operation since
2013 and expected to produce between 80,000
oz and 87,500 oz of gold this year, Mt Carlton is
one of Evolution Mining’s key gold mines in the
state of Queensland (Australia), where Evolution
is the top gold producer. MAXAM will supply all
blasting solutions for the next three (with options
to extend) years, providing down the hole
services by supplying its flagship RIOFLEX bulk
explosive together with a complete range of
RIONEL initiation systems.
Additionally, MAXAM is building a customised
Mobile Service Unit (MSU) to specifically adapt
to the site’s ‘surface mining’ conditions involving
difficult terrain contours. To provide the best
possible service, it has also built an on-site
storage and reload facility to optimise
performance and reduce service delivery time.
Cowal gold mine, situated 350 km west of
Sydney in the traditional lands of the Wiradjuri
people on the south-east coast of Australia,
began operations in 2005. The mine is an open