Registration Dossier

Physical & Chemical properties

Particle size distribution (Granulometry)

Administrative data

Endpoint:
particle size distribution (granulometry)
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2010
Report date:
2010

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
kerneos reference methods: INS L017 CL : Sieving quartering
kerneos reference methods: INS L012 CL : Laser grading - dry process
GLP compliance:
not specified
Type of distribution:
other: particle size distribution

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report):ALAG® (0-1 mm)
- Substance type: mineral
- Physical state: powder

Results and discussion

Particle sizeopen allclose all
Percentile:
D50
Mean:
> 100 µm
Remarks on result:
other: The mean diameter of 50 % of particles by weight (sieving methods) lies in between 315 and 500 µm. Therefore the MMAD is above 100 µm.(migrated from fields under 'Mass median diameter' as D50 percentile. No source field for Standard deviation.)
Percentile:
D10
Mean:
15.2 µm
Remarks on result:
other: These mean diameters have been worked out from a population of particles already below 100 µm, under 1 bar
Percentile:
D50
Mean:
62.6 µm
Remarks on result:
other: These mean diameters have been worked out from a population of particles already below 100 µm, under 1 bar
Percentile:
D90
Mean:
134
Remarks on result:
other: These mean diameters have been worked out from a population of particles already below 100 µm, under 1 bar
Particle size distribution at different passagesopen allclose all
No.:
#1
Size:
2.5 mm
Distribution:
0 %
Remarks on result:
other: cumulative reject
No.:
#2
Size:
1 mm
Distribution:
0.071 %
Remarks on result:
other: cumulative reject
No.:
#3
Size:
0.8 mm
Distribution:
8.53 %
Remarks on result:
other: cumulative reject
No.:
#4
Size:
0.5 mm
Distribution:
41.93 %
Remarks on result:
other: cumulative reject
No.:
#5
Size:
0.315 mm
Distribution:
61.7 %
Remarks on result:
other: cumulative reject
No.:
#6
Size:
0.25 mm
Distribution:
70.53 %
Remarks on result:
other: cumulative reject
No.:
#7
Size:
0.2 mm
Distribution:
74.27 %
Remarks on result:
other: cumulative reject
No.:
#8
Size:
0.1 mm
Distribution:
86.17 %
Remarks on result:
other: cumulative reject
No.:
#9
Size:
< 100 µm
Distribution:
10.6
Remarks on result:
other: cumulative reject

Any other information on results incl. tables

In order to be more accurate with the distribution, measures have been carried out under 4 different pressures of the ejector:

INF to 100µm D10  D20  D25  D50   D75  D80  D90
under 1 bar  15.2 29.9  35.8 62.6  96.9  106.7  134 
under 2 bars 12.3  26.1  31.9 57.9  90.8  100.1  126.1 
under 3 bars 10.8  23.8  29.5  54.9  86.8  95.8  120.9 
 under 4 bars 10  22.7  28.4  53.6  85.2  94.2  119.4 

This table indicates the diameter lower than the % indicated. For example, 10% of the particles lower than 100 µm have a diameter of 15.2 µm under an ejector pressure of 1 relative bar, and 12.3 µm under a pressure of 2bar

According to the attached graph, it can be seen that 0.62% of the particles under 100 µm have a diameter lower than 4 µm.

The sieving measures show that the medium diameter at 50% in weight is between 315 and 500 µm, probably above 400µm, so the Mass Median Aerodynamic Diameter (MMAD) is assuredly above 100 µm.

Applicant's summary and conclusion

Conclusions:
The mass median aerodynamic diameter (MMAD) is above 100 µm and that 0.62% of the particles under 100 µm have a diameter lower than 4 µm under 1 bar
Executive summary:

The sieving method applied to Alag® has shown that the percentage cumulative reject for a 0.1 mm mesh size was 86.17 % . However the laser method used for the same particles showed that the particles geometric shape is not spheric and it explains why a 100 µm sieve allows them to pass through why the particles may have a lenght longer than 100 µm. The laser measures show that, among the particles below 100 µm, 10 % of particles have a diameter below 15.2 µm, 50 % a diameter below 62.6 µm and 90% a diameter below 134.0 µm. Further measures and extrapolations give the following results: the mass median aerodynamic diameter is above 100 µm and that the 0.62% of the particles under 100 µm have a diameter lower than 4 µm under 1 bar