Bloomfield Mine is an open cut coal mine owned and operated by The Bloomfield Group, in the Hunter Valley, NSW.
The Challenge: Soft Ground and Wet Conditions
Bloomfield Mine, located near residential areas in the Hunter Valley, has always prioritized managing the environmental effects of their operations. One particular area of concern was their blasting process, especially in soft and wet ground conditions.
Traditionally, when faced with wet ground that precluded the use of ANFO (Ammonium Nitrate/Fuel Oil), blasting engineers had to resort to using Fortis™ Coal, a pumped emulsion blend with 44% more energy than ANFO. While effective, this solution came with two significant drawbacks:
- Increased Fume Production: The excess energy in soft ground often resulted in post-blast fume, a potential environmental hazard.
- Higher Costs: The higher density and cost of Fortis™ Coal directly increased the unit cost of blasting.
The Solution: Enter 4D™ Bulk System
To address these issues, Bloomfield partnered with Orica to implement the innovative 4D™ Bulk System. This system offers several advantages:
- Flexibility: It provides a range of higher and lower energy bulk explosives suitable for various ground conditions.
- Precision: The system automatically manages the delivery to achieve the specified average relative bulk strength (RBS) for each blasthole.
- Simplicity: Blasting engineers can simply select a product based on hole water condition and energy level, while the LOADPlus™ system handles the calculations and controls.
The Implementation
The demonstration blast at Bloomfield used Fortis 4D™ Coal 110 & 130, replacing the standard Fortis™ Coal 1.15g/cm³. The new system was used across bench heights ranging from 6m to 20m, with i-kon III electronic detonators for initiation.
The Results: A Win-Win Situation
The implementation of the 4D™ system yielded impressive results:
- Reduced Explosive Strength: The average bulk strength of explosives was reduced by 20%.
- Lower Powder Factor: Overall powder factor decreased by 12% compared to conventional pumped emulsion blends.
- Improved Environmental Performance: No fume was observed during the demonstration blast.
- Maintained Productivity: Dig rates remained consistent with those in conventional blasts.
The Verdict
Scott Dark, Drill & Blast Supervisor at Bloomfield Group, summed up the success:
We are happy with the performance of 4D and it was really important to reduce the energy in soft ground conditions. It had better fume performance compared to traditional products, due to the lower density energy in soft geology.
This case study from Bloomfield Mine demonstrates that with innovative thinking and the right technology, it's possible to improve both economic and environmental outcomes in mining operations. It's a testament to the ongoing efforts in the industry to develop more sustainable mining practices.
About 4D™
Orica's 4D™ is a revolutionary bulk explosives system that offers unparalleled blast control by delivering precise explosives energy tailored to varying geological conditions.
4D™ technology is transforming how customers blast compared to conventional solutions. 4D™ surface expands the envelope of explosive energy by decreasing energy by 43% and increasing energy by 23%. Explosives energy can now be tailored to match the geology of each hole irrespective of whether the hole is dry, dewatered or wet.
4D™ can help customers reduce bulk explosives consumption and maintain their license to operate when mining in sensitive environments. At Bloomfield coal's open cut mine in NSW, the 4D™ system effectively managed environmental effects, achieved a 20% reduction in bulk strength and a 12% decrease in powder factor, whilst eliminating fume events and maintaining fleet productivity.
The increased and consistent energy profile of 4D™ is also used to optimise fragmentation, reduce cap rock, and improve the efficiency of the load and haul fleet and ore processing at the mill.
Find out more about 4D and visit www.orica.com/4D