[Disclaimer: This presentation constitutes an integral component of a designated course curriculum and is crafted and disseminated for its intended audience. None of the contents within this presentation should be construed as a formal publication on the subject matter. The author has extensively referenced published resources in the preparation of this presentation, and proper citations will be provided in the bibliography upon completion of its development.] Rock fragmentation analysis and particle size distribution are crucial aspects of mining operations, offering insights into the efficiency of blasting techniques and subsequent processing. Rosin-Rammler distribution equation, a fundamental tool in this analysis, provides a mathematical framework to model particle size distribution. By employing this equation, mining engineers and geologists can precisely evaluate the distribution of fragmented rock particles. This analysis aids in understanding the efficiency of blasting operations, enabling adjustments to optimize fragmentation for further processing. The Rosin-Rammler distribution equation is especially valuable in predicting the percentage of rock particles below a certain size, crucial information for designing crushers, mills, and other processing equipment. By studying the distribution pattern, mining professionals can make informed decisions about equipment capacity and energy requirements. This data-driven approach enhances operational efficiency, reduces energy consumption, and ultimately contributes to sustainable mining practices. Accurate rock fragmentation analysis using the Rosin-Rammler distribution equation is indispensable in modern mining, ensuring the industry operates efficiently while minimizing environmental impact.

1. Rock Fragmentation
Analysis using
Granulometric Software
A presentation by
Romil Mishra
PhD Candidate
Department of Mining Engineering
IIT (ISM) Dhanbad)

2. Properties of good fragmentation

3. Optimum rock fragmentation
 The rock fragmentation obtained as an outcome of
blasting operations is said to be optimum, when it
contains maximum percentage of fragments in the
desired range of size.
 The Desired size usually means the size that is
demanded and can be effectively utilized by the
consumers for further operations devoid of any
processing.
 The optimum size for different consumers is
different.
Optimum rock fragmentation can be achieved by
optimizing the controllable parameters and
should be designed in such a manner that the
uncontrollable parameters do not affect the
fragmentation much.

4. Quantification of Rock fragmentation
 Mean Fragment Size or D50 particle size: It denotes the particular size of the rock (in mm) below which 50%
of the fragments (by weight) in the imaged muck pile lie.
 Percent passing from 500 mm sieve size: It is the percentage of material in the muckpile which are below
500 mm size.

5. Methods of fragmentation analysis
Methods of Fragmentation Assessment
Indirect
Oversize boulder count method.
Explosive consumption in secondary blasting method.
Shovel loading rate method.
Bridging delays at the crusher method.
Direct
Sieving or Screening.
Visual analysis method.
Photographic or manual analysis method.
Image analysis method.

6. WipFrag Image Analysis Software
 Granulometry software
 It utilizes the technique of measurement of fragmentation with the help of digital scaled images
of blasted muck pile.
 These images are then transferred to the WipFrag system for analysis

7. Image sampling

8. WipFrag Software interface demo

9. Data
interpretation

10. Fragalyst

11. Image Calibration

12. Image Processing

13. Image Resizing

14. Edge detection

15. Edge detection under process

16. Segmentation

17. Manual editing

18. Segmentation after Manual editing

19. Input rock density

20. Blasted Block Size Distribution

21. Blasted Block Size Distribution (with fines correction)

22. Rosin-Rammler Model for Particle Size Distribution

23. Rosin-Rammler Model as used in Blasting
Source:
Rustan, A., Cunningham, C., Fourney, W., Spathis, A., & Simha, K.R.Y. (Eds.). (2010). Mining and Rock Construction Technology Desk Reference: Rock
Mechanics, Drilling & Blasting (1st ed.). CRC Press. https://doi.org/10.1201/b10543

24. Size ranges Weight (%)
Nominal size
(x)
Cumulative
Weight (%)
Retained
Cumulative
Weight (%)
Passing
30 and above 18 30 18 82
30 to 21.2 14 21.2 32 68
21.2 to 15.0 14 15 46 54
15.0 to 10.6 15 10.6 61 39
10.6 to 7.5 12 7.5 73 27
7.5 to 5.3 10 5.3 83 17
5.3 to 3.75 12 3.75 95 5
3.75 and below 5 0 100 0
Sample data sheet of a fragmentation distribution