Around the world, one of the biggest users of all types of explosives is the mining industry. The vast majority of all blasting materials sold in North America go directly to the mining industry, with a much smaller percentage to quarrying, the oil and gas industries, construction and then finally demolition.
With new technology and formulas in different types of blasting options, there is a wider choice of blasting materials. This allows the blasting operator to choose the correct option for the specific type of operation required.
ANFO or ammonium nitrate-fuel oil mixes are the most common. These can include slurries, emulsions or water gels, with the ammonium nitrate found in a prilled form or in grains or a liquid form. These are classified as high explosives because they require some form of a blasting cap to initiate the explosion.
ANFO can be used for cast blasts, which are designed to move existing soil off of areas of new coal by moving the overburden into the existing area already mined. This can move as much as 80% of the soil; the rest is then moved with equipment, greatly speeding up the process.
With fragmentation blasting, there is no desire to move the surface, but simply to break up the underlying layers of rock. In this type of blast, two types of explosives are used in each hole; the higher energy blast will occur deeper in the earth and the lower energy near the surface creating the breaking without the upward explosion.
Dynamite is still used as one of the key explosives in mining in the United States as well as in other countries around the world. Dynamite, like ANFO, is a high explosive because it also requires a blasting cap, although dynamite, when not properly stored or when allowed to age, can become very shock sensitive.
This particular blasting option is often used for very precise types of applications such as a process known as blast mining. This is an older practice, but it targets specific seams of coal and uses the specifically placed blast to break the coal loose and allow it to then be loaded and moved.
Working with a top blasting service is essential for mine owners and operators to ensure the blast is effective, efficient and conforms to their blasting needs and the needs of the mine. With the right type of blast there is less cost, less additional work, and quicker access to obtaining the coal or minerals.