PT DAHANA (Persero)’s Energetic Material Center (EMC) issued one of the superior products for blasting of complex rock structures under the product name DAHANA Water Gel (DAWAGEL). This DAHANA innovation product has also been trusted by coal mining and quarry companies in the country.
Dawagel is a bulk explosive gel which is highly adaptive to the walls of the blast hole whether it is hollow or porous, so as to minimize decoupling and under perfect reaction conditions, the gel bond between the elements is very strong to make sure it remains stable in maintaining the formation of the explosive column in the hole, which means it will not melt into cavities or crevices as is often the case with other liquid explosives.
The challenge started from rock conditions in the limestone quarry owned by PT Semen Tonasa – Pangkep, South Sulawesi, where the rock structure is complex, porous, and fractured and sometimes cavities are found. This has several times resulted in the process of rock scattering when blasting becomes less optimum. Boulder is still in fragmentation resulting from blasting. It is possible that excavation cannot be done due to the release of energy that is concentrated in the loose zone because of cavities in the blast hole wall.
Through a research process, the DAHANA EMC Team has succeeded in designing Dawagel as a product that can be used in limestone structures, with an explosive density of between 0.7-0.78 gr/cc, with a smaller composition of Ammonium Nitrate while VOD The resulting output is between 3,800 m/s – 4,250 m/s at a 4.5 Inch hole diameter.
According to DAHANA’s Director of Operations, Bambang Agung, the results of blasting using Dawagel products in the PT Semen Tonasa quarry have proven satisfactory performance of the blasting results. The resulting fragmentation is less than 30 cm as much as 89.15%, and the VOD of the product reaches 4,128 m/s. Economically, it has succeeded in reducing the blasting cost component by 5% – 10% in 15 blasts during the trial period.
“Dawagel products have the advantage of replacing ANFO with a lower density but with a higher VOD than ANFO. This type of explosives is also very suitable for mining types with hollow rock, such as in the cement industry,” said Mr Agung.
For application, Dawagel Products use DAHANA’s Mobile Manufacturing Truck (MMT), a DAHANA technology that is capable of producing explosives directly at the blasting location, allowing more economical process for the consumers.
Owing to all the advantages in the initial phase of penetration into the mining market, Dawagel products have subsequently won the trust to be used in coal mining operations, as is currently running at PT Pamapersada Nusantara – Trubaindo Coal Mining, Melak, East Kalimantan. DAHANA’s Director of Operations hopes that Dawagel will get a wider market in the general mining sector.
“It is our hope that this product will continue to be widely used in the mining market, especially in the coal mining sector, so that mining operational costs can be more balanced with fluctuations in highly uncertain commodity prices,” concluded Mr Agung.
