Explosives and Blasting (화약ㆍ발파)

Korean Society of Explosives and Blasting Engineering (대한화약발파공학회)
권호 표지

Blast Design for Improvement of Limestone Fragmentation

석회석 파쇄도 향상을 위한 발파 설계

  • Piyush, Rai (Dept. of Energy & Resources Eng., Chonnam National University, Dept. of Mining Eng., Banaras Hindu University) ;
  • Yang, Hyung-Sik (Dept. of Energy & Resources Eng., Chonnam National University)
  • 피유시 라이 (Banaras 대학 광산공학과, 전남대학교 에너지자원공학과) ;
  • 양형식 (전남대학교 에너지자원공학과)
  • Received : 2010.05.26
  • Accepted : 2010.06.21
  • Published : 2010.06.30
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Abstract

The paper presents a case study of a limestone quarry of the Philippines, where major problems in terms of improper fragmentation, poor wall control, and poor heave of the muck pile were witnessed. The paper highlights the significant role of switching over from diagonal firing pattern to V-type firing pattern, and also of making suitable adjustments in the stemming column length for improved confinement and gas retention. The study revealed that by making aforesaid design modifications in the blast round, marked improvement in blasting results was registered. Looking at the results, it was further contemplated to expand the mesh area in the subsequent blast rounds. The mesh area was incremented from the existing $8.96m^2$ to $12m^2$. The results were meticulously registered in the field, and clearly depicted definite improvements in the blast results in terms of increased P.F., reduced boulder count, reduced FEL cycle time, reduced dozing hours and improved heave.

이 논문은 필리핀 석회석 광산에 적용한 연구 결과로서 이 광산에서는 파쇄석 입도분포가 좋지 않고 벽면의 유지나 파쇄석 더미의 분산이 불량하였다. 기폭패턴을 대각선 방식에서 V 타입으로 바꾸고 전색장을 조정하여 저항과 가스압의 유지기간을 향상시켰다. 이를 통하여 발파결과가 향상되었다. 특히 공당발파영역이 넓어진 것으로써 그 성과를 확인할 수 있다. 공당발파영역은 기존의 $8.96m^2$에서 $12m^2$로 넓어졌다. 화약계수는 증가하였고 대괴의 수는 감소하였으며, 전방적재기의 행정시간이 감소하였다. 또 공전 시간이 줄었으며 적재높이가 향상되었다.

Keywords

References

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