ANALYSIS OF THE EFFECT OF ANFO FILL DEVIATION IN BLAST HOLE ON FRAGMENTATION OF BLASTING RESULTS IN OPEN PIT MINING PT PAMAPERSADA NUSANTARA SITE ANUGERAH BARA KALTIM

• Main Author: Valdiala, Arsendo
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/66551
• Institution: Institut Teknologi Bandung

Blasting is a method that used to scatter rock into smaller size that known as fragmentation of blasting result. Fragmentation that hoped is have a suitable size for loader so that can ease loading process. PT Pamapersada Nusantara site Anugerah Bara Kaltim has a problem about fragmentation that is the blasting activity resulting 36% boulder (the fragmentation that have size more than 70 cm) of all blasting result, where the standard of boulders quantity that allowed is only 5%. The problem about fragmentation also effects to loading activities that is digging time of loader that exceeds the standar 12 second while loading blasted materials. In an investigation, it is known that the cause is the distribution of energy vertically that didn’t spread evenly because the quantity of ANFO in every blast hole are less than the plan that is 50% of hole depth and it is caused from the charging unit that inaccurate that known as ANFO truck or mobile mixing unit (MMU) that related to ANFOCON system that used. The purpose of this research is to solve the problem by knowing the effects of ANFO fill deviation on fragmentation and knowing a method to prevent the ANFO fill deviation for keep the quality of the fragmentation. It is known that there is a ANFO fill deviation, that is the quantity is less as much as 7.2 kg so the quantity of ANFO in every blast hole is only 43% of hole depth. This deviation is caused by clogged ANFO materials at MMU and ANFOCON system that inaccurate so should be repaired that’s like doing a calibration every certain period. After the repairment, the quantity of ANFO in every blast hole are back to be 50% of hole depth so the charging unit can be said has been accurate. That is can effect to the quality of fragmentation that improved where the quantity of boulder is only 6% that goes to allowed standard and no more digging time of loader that exceeds the standard after loading blasted materials that resulted by repair.