Let’s admit it, in many sectors, our industry is dragging its feet post Olympic fever and the GST. Most of us are reminiscing about the early months of 2000. Remember those days? Clients on the phone screaming for more rock and trucks lining up at the weighbridge! Unfortunately for most, those days are (for now at least) past.
There are, however, clear signs of improvement on the horizon. For example, some of the latest industry indicators are encouraging, showing that we can look forward a brighter year ahead. During the last few months we have seen that the recovery of the house-building industry is underway: dwelling approvals and number of dwellings financed are showing clear signs of improvement.
In the meantime, we can not be complacent. Quarry operators need to look very closely at their financial performance.
Today, the most common question asked of a quarry supplier seems to be “How can you help me improve the bottom line?” It is no secret that all quarries, both large and small, are focussed on reducing costs. Returns are still very low and every dollar saved is crucial in the never-ending battle to deliver shareholders acceptable returns.
In a tough environment, some operators may be tempted to cut corners or make shortsighted decisions. One such decision could be buying explosives or blasting services exclusively on the basis of price, without considering factors such as performance, quality or even service standards.
The intention of this editorial is to highlight some pitfalls encountered by explosives users and solutions that may assist in overcoming them. We will start by providing a recent example of how a ‘Back to Basics’ approach has significantly improved efficiencies at BORAL Orange Grove Quarry (Perth)
UEE Explosives testing at Orange Grove (Perth)
This BORAL quarry has been testing UEE’s RIOFLEX bulk explosive, a premium product designed to facilitate blast optimisation. The goal was to reduce costs by using the best possible type of explosive and by expanding the drilling pattern. Savings have been achieved by drilling fewer metres and using fewer accessories.
The results of the tests have been excellent. The expanded pattern has not compromised fragmentation, diggability or oversize. In fact, the results have been quite the opposite.
Additional improvements were also identified in areas such as “power trough” and “heave”. Compared to a standard Emulsion shot, muckpile spread is going 30mts further and 5mts lower in height.
Other areas for improvement, such as the flexibility to use lower density RIOFLEX for the trim holes on the final pit boundary, have been also identified.
Together with Boral Orange Grove, UEE is now assessing further pattern expansions to achieve even greater savings and maintain outstanding blasting results.
These successful trials paved the way to a formal agreement between Boral Ltd and UEE Explosives to supply several quarries Australia wide.
Follow these tips
Blast optimisation is a complex process with many variables to consider. However, it is very difficult to account for every variable in any given situation. At UEE we recommend a ‘Back to Basics’ approach to blasting. All in all, the following six tips will help you achieve real cost reductions:
1. Trial different bulk explosives – and measure the results
2. Do not let technology carry you away
3. Control your blast design: Use Laser Profile and Boretracking
4. Use the best value, not the lowest priced bulk explosives
5. Pay attention to the quality of downhole delivery
6. Seek to expand your drilling pattern
JJ Montoro, UEE Explosives’ Technical Manager, will expand on our ‘Back to Basics’ tips. We are confident that these tips will help your business achieve real efficiencies.
Regardless of the supplier, products and prediction models used, and “bells and whistles” applied never forget this: good blasting always requires a properly drilled hole filled with the best quality explosive.
If you really want to reduce your costs, perhaps the best option is to “…go back to basics”.
Xavier Montaner
Managing Director
UEE Explosives
1st Tip: Test different bulk explosives
In order to assess different bulk explosives the best approach is to do full-scale production blasts with the explosives in question. This would allow for testing of not only the explosive but also the quality of a company’s products, services, and overall responsiveness.
In short, it is an opportunity to put to rest all those perceptions about different explosives or suppliers. Field evaluations will give you a better indication of what to expect from a given explosive at a particular quarry.
There is a perception in the market that bulk explosives are ‘emulsion explosives’. This perception is not accurate. The main reason for some explosives companies switching their explosive technology to emulsions was the need to compete in the big mining markets.
Emulsions were designed as low cost explosives for the mining industry. They find their best application in mining where big hole diameters and quantities can justify a sacrifice in performance for a lower unit cost. In mining, fragmentation and heave are not the main goal as most of the rock blasted will go to the dump handled by huge loading and hauling equipment. Primary crushing is not the focus when secondary and tertiary crushing will be required to reduce the output to micron size, which is beyond the range of explosive fragmentation.
In contrast to this, most of the rock in quarry applications has to be crushed and sold as a low cost product for the construction industry. These different realities mean that while emulsions are the most cost-effective choice for large mining applications, this may not necessarily be so for quarries.
Although the international UEE Group has a proprietary emulsion, we decided to follow the watergel option for the Australian quarry market. In this environment, we believe that watergels provide significant benefits such as improved fragmentation, “heave” and diggability.
UEE Australia’s quarry focus has been the driver to develop RIOFLEX watergel technology. This development has been so successful that RIOFLEX is now being used in overseas quarry markets and in very demanding applications such as underwater blasting.
2nd Tip: Do not let technology carry you away
Pressure from users to lower the cost of blasting has resulted in explosives suppliers delivering low cost bulk explosives with the implicitly adopted, self-defeating strategy that there is not a lot to improve in the chemistry of explosives. Wrongly, the focus of blasting improvement has shifted from blast design and explosive performance to more esoteric fields like ‘Blast Management Systems’, ‘Environmental Excellence’, ‘Computer Blasting Simulation and Modeling’, and the like. With such a large number of tools, however, there is a danger that you may end up confused and find it difficult to obtain real value and guidance.
The latest fashionable attempt to ‘square the circle of explosives’ is optimization of the whole operational cycle from blasting through to loading, hauling and crushing. A number of models have been published in literature that entails a mass and energy balance applied to the quarry operation. Although conceptually simple, these models require extensive resources to provide meaningful input data and the results (which justify the cost) are only achievable on a long-term basis. This explains why these theoretical models have not been widely implemented.
One of the common pitfalls of programs monitoring blasting effects is under-resourcing. Lack of resources tends to produce half-hearted or piece-meal measurements, with the resulting improvement processes likely to be based on partial information.
No matter how much sophistication a supplier tries to build around their product, with buzz words and technical mumbo-jumbo, the basic fact remains that the pre-requisite for a good blast result is a properly designed shot that is drilled according to specifications and filled with the best possible explosive. Most of the time, this ‘Back to Basics’ approach also minimises costs.
3rd Tip: Control your blast design: Use Laser Profile and Boretracking
Of all the new blasting technologies, perhaps Laser Profiling and Boretracking can be credited with making the most significant contribution to the improvement of blast results and achievement of environmental compliance. UEE recognized this fact a long time ago and this function, today, is an integral part of our services.
Using this capability not only helps to demonstrate due diligence in discharging your environmental duties but also ensures a high standard of blast design. It also allows for continuous feedback to the driller so that he / she has a baseline for improvement.
Altogether, using Laser Profiling and Boretracking removes much of the guess-work so common in the blasting landscape, and substitutes it with measured parameters.
4th Tip: Use the best, not the cheapest bulk explosives
It is well known and documented that the most efficient way to break rock is on the bench and by using explosives. Do not compromise on the quality of explosives.
UEE has challenged the basic tenets of the quarry blasting market and has brought new ideas and developments to blasting in hard rock. This has been in an attempt to provide choice and disprove the theory that bulk explosives are simply commodities like fuel or toothpaste.
This fresh approach has delivered the highly successful RIOFLEX bulk explosives together with the specially designed and locally built RIOFLEX MSUs (Mobile Sensitising Units).
Although RIOFLEX is certainly a very competitive product it might not necessarily be the cheapest in the market. RIOFLEX is being trialed constantly against competing bulk explosives in the quarry market and its benefits clearly justify using it as an alternative to other products. Our experiences result in the following:
No need for different patterns dry/wet
Pattern expansion of up to 30%
Excellent results in vertical or near vertical drilling (5 degrees) without increasing toe. This is the result of RIOFLEX’s high energy. The quality of quarry faces also improves with drilling angles.Near vertical drilling minimises chances of poor drilling
Back break is not significantly affected by using RIOFLEX in near vertical drilled faces
RIOFLEX allows for the reduction of subdrilling that keeps quarry floors in good condition for future drilling
Accurate control of stemming lengths (+/- 0.1m) as chemical gassing is not used with RIOFLEX. This allows for an outstanding control of environmental side effects of blasting: vibration and air blast
Improved heave and muckpile motion.
Improved diggability and fragmentation.
Reduced drilling and accessories costs through pattern expansion.
5th Tip: Pay attention to the quality of downhole delivery
Quarry blasting has its own peculiar requirements, particularly fragmentation and environmental control. UEE considers quality of delivery to be one of the most important contributors to blast results and environmental performance. As such, a great deal of effort and resources went into considering these issues during the development stages of the RIOFLEX system.
UEE’s MSUs were developed using the ‘quarry hole’ as the basis for design and engineering. They are specifically designed and optimized to load 76 to 102 mm holes, the standard range for quarry blasting. Protecting the hole and ensuring that every hole is loaded to the same standard and to the required stemming length is achieved by pumping a non-chemically-gassed product using specially designed collar protectors and pump-synchronised automatic retraction hose reels.
6th Tip: Seek to expand your drilling pattern
With the exception of a few special cases, some expansion of the blast hole pattern will usually deliver significant benefits and reduce costs. As a general rule, patterns should be expanded to the maximum allowable given by the particular site conditions. Increasing patterns translates into putting as much energy as possible into the hole using high performance bulk explosives. RIOFLEX allows for very impressive pattern expansions – due to its superior energy release characteristics.
This strategy requires changing the mindset of minimising the expenditure in the explosive component of blasting. It is common to encounter the advocate of ANFO who does not accept that blasting costs can be reduced by using bulk explosives. Such a strong perception of the benefits of cheap explosives may prevent true cost reduction.
By expanding patterns and using explosives that are suited to all weather and ground conditions, you eliminate the effect of water in blast planning. In our experience, quarry personnel tend to be very optimistic when evaluating the percentage of wet/dry shots or holes. The reality is generally a situation with a higher percentage of wet holes than expected. Such optimism is often enough to blow out the best calculated budget estimates.
JJ Montoro
Technical Manager
UEE Explosives