APLIKASI AIR DECKING MENGGUNAKAN BALLDECK GUNA MENGEFISIENSI BAHAN PELEDAK PADA KEGIATAN PELEDAKAN OVERBURDEN DI PT HANWHA MINING SERVICES

Abstract

The research was carried out in Pit T1 of PT Sebuku Tanjung Coal, Kotabaru Regency, South Kalimantan Province. The powder factor of conventional blasting is quite high so that the cost of explosives required is very large. One of the efforts to reduce the use of explosives is the addition of air decking on the blast hole with Ball Deck media. This study aims to reduce the powder factor in overburden blasting and to make working time more efficient. The research was conducted by comparing the actual and theoretical data, as well as analyzing the statistics of conventional blasting and air decking blasting. The important parameters in the comparison are blasting geometry, work efficiency, powder factor, and average fragmentation. The burden and spacing used in conventional blasting and air decking blasting is 8m × 9m. The average working time required for conventional blasting is 1 hour 33 minutes, while for air decking blasting with the top air deck method it is 1 hour 15 minutes. The average powder factor in conventional blasting is 0.20 kg/BCM but air decking blasting is able to optimize up to 0.17 kg/BCM. The average fragmentation yield from conventional blasting was 59.29 cm, while in air decking blasting it was 65.54 cm. In addition, the air decking blasting can reduce the use of explosives by 12-20% per hole and can reduce the cost of explosives up to 4.82% per hole.