Sieving Final Report

Please use as reference. Some data may be erroneous.

1. SIEVING


ELECCION, NICELY JANE R.
Department of Chemical Engineering
College of Engineering and Architecture
Cebu Institute of Technology – University
N. Bacalso Ave., Cebu City 6000



Sieve analysis is used to obtain the particle size distribution of a solid material by
determining the amount of powder retained on a series of sieves with different sized
apertures. This experiment aims to perform the differential and cumulative analysis of a
given sample and to determine the particle population, and average particle size of a
sample by the case of a screen analysis. Plotting the data between the sizes of the particle
versus the mass fraction of the material retained in the screen, a bell shape curves was
generated. This implies that this variable is not directly proportional to each other because
no linear relationship is evident between them.















Engr. Jennifer M. Fernandez


March 13, 2018

2. 1. Introduction
Screening defines as the separation of mixture of particles of various sizes into two
or more fractions by a screening surface. Different methods for determining the size
distribution is present and one of which is the sieve analysis – the oldest and the best-
known method. The particle size distribution is defined via the mass or volume. In sieve
analysis, the particulate material is divided into size fractions and the weight of these
fractions are determined. In this way analysis on a relatively broad particle size spectrum
is quick and reliable. During sieving the sample is subjected to horizontal or vertical
movement in accordance with the chosen method. This causes a relative movement
between the particles and the sieve; depending on their size, the individual particles either
pass through the sieve mesh or are retained on the sieve surface. The likelihood of a
particle passing through the sieve mesh is determined by the ratio of the particle size to
the sieve openings, the orientation of the particle and the number of encounters between
the particle and the mesh openings.

3. 2. Materials and Methods
2.1 Equipment and Materials
 Standard Tyler Testing Sieves (with cover and pan)
 Sieve Shaker
 Beakers
 Brush
 Analytical Balance
 Mass of Calcium Carbonate (CaCO3)

2.2 Methods
A 200 g dry sample of Calcium Carbonate was weighed. The sieves were
made sure to be clean and are assembled in decreasing order of sieve number
with the smallest sieve number at the topmost of the experiment. The Calcium
Carbonate that was weighed was placed in the mechanical shaker and was shaken
at the preferred time interval. The stack was carefully weighed from the shaker and
the retained mass of the sample in each sieve was weighed and reordered. The
mass fractions per sieve were calculated. Two trials per time interval were
repeated with the same procedure.

4. 3. Results
Table 3. Tabulated data on the experimental results
ITEM
TEST NUMBER
2 minutes 4 minutes 6 minutes
Trial 1 Trial 2 Trial 1 Trial 2 Trial 1 Trial 2
Feed Material CaCO3 CaCO3 CaCO3 CaCO3 CaCO3 CaCO3
Quantity (g) 200 200 200 200 200 200
Through Retained

- 10 mesh 0.441 0.4725 0.0945 0.1365 0.0315 0.168
10 mesh 20 mesh 0.021 0.126 1.0395 0.2415 3.5985 3.801
20 mesh 40 mesh 11.256 11.13 8.2425 8.127 44.436 44.415
40 mesh 60 mesh 62.433 60.585 43.2495 40.8345 66.8745 64.806
60 mesh 80 mesh 54.3795 44.52 51.576 49.665 51.1245 49.014
80 mesh 100 mesh 60.963 58.863 64.617 63.84 33.222 32.52
200 mesh Pan 18.48 26.607 37.695 43.6695 8.82 12.894
Total (g) 207.9735 202.3035 206.514 206.514 208.107 207.618

Figure 3.1 Semi-Log Graph for Sieve Analysis for Trial 1

1
10
100
0 50 100 150 200 250
% Finery
Mesh No.
Cumulative Analysis of Trial 1
2 minutes
4 minutes
6 minutes

5. Figure 3.2 Semi-Log Graph for Sieve Analysis for Trial 2

4. Calculations

Trial 1 Trial 2

@ 2 minutes

Mesh no. 10 =
0.441
207.9735
??????100 = 0.212% Mesh no. 10 =
0.4725
202.3035
??????100 = 0.23%
Mesh no. 20 =
0.021
207.9735
??????100 = 0.0101% Mesh no. 20 =
0.126
202.3035
??????100 = 0.062%
Mesh no. 40 =
11.256
207.9735
??????100 = 5.40% Mesh no. 40 =
11.13
202.3035
??????100 = 5.50%
Mesh no. 60 =
62.433
207.9735
??????100 = 30.00% Mesh no. 60 =
60.585
202.3035
??????100 = 29.95%
Mesh no. 80 =
54.3795
207.9735
??????100 = 26.10% Mesh no. 80 =
44.52
202.3035
??????100 = 22.01%
Mesh no. 100 =
60.963
207.9735
??????100 = 29.30% Mesh no. 100 =
58.863
202.3035
??????100 = 29.10%
pan =
18.48
207.9735
??????100 = 8.90% pan =
26.607
202.3035
??????100 = 13.15%

1
10
100
0 50 100 150 200
% Finery
Mesh No.
Cumulative Analysis of Trial 2
2 mintues
4 minutes
6 minutes

6. @ 4 minutes

Mesh no. 10 =
0.0945
206.514
??????100 = 0.05% Mesh no. 10 =
0.1365
206.514
??????100 = 0.066%
Mesh no. 20 =
1.0395
206.514
??????100 = 0.503% Mesh no. 20 =
0.2415
206.514
??????100 = 0.12 %
Mesh no. 40 =
8.2425
206.514
??????100 = 3.99% Mesh no. 40 =
8.127
206.514
??????100 = 3.94%
Mesh no. 60 =
43.2495
206.514
??????100 = 20.94% Mesh no. 60 =
40.8345
206.514
??????100 = 19.77%
Mesh no. 80 =
51.576
206.514
??????100 = 24.97% Mesh no. 80 =
49.665
206.514
??????100 = 24.04%
Mesh no. 100 =
64.617
206.514
??????100 = 31.29% Mesh no. 100 =
63.84
206.514
??????100 = 30.91%
pan =
37.695
206.514
??????100 = 18.25% pan =
43.6695
206.514
??????100 = 21.15%


@ 6 minutes
Mesh no. 10 =
0.0315
208.107
??????100 = 0.015% Mesh no. 10 =
0.168
207.618
??????100 = 0.081%
Mesh no. 20 =
3.5985
208.107
??????100 = 1.73% Mesh no. 20 =
3.801
207.618
??????100 = 1.83%
Mesh no. 40 =
44.436
208.107
??????100 = 21.35% Mesh no. 40 =
44.415
207.618
??????100 = 21.39%
Mesh no. 60 =
66.87455
208.107
??????100 = 32.3% Mesh no. 60 =
64.806
207.618
??????100 = 31.21%
Mesh no. 80 =
51.1245
208.107
??????100 = 24.57% Mesh no. 80 =
49.014
207.618
??????100 = 23.61%
Mesh no. 100 =
33.222
208.107
??????100 = 15.96% Mesh no. 100 =
32.52
207.618
??????100 = 15.66%
pan =
8.82
208.107
??????100 = 4.24% pan =
12.894
207.618
??????100 = 6.21%

7. 5. Sketch

8. 6. Discussion
Various preconditions must be fulfilled for a reproducible and meaningful sieve
analysis and the settings must also be properly adapted. The most important criteria are
the following: there must be a representative part-sample - ‘Representative’ means that
the properties of the part-sample, in this case the particle distribution, must be identical
to the properties of the whole bulk material to be sampled. Another one is a calibrated
and certified test sieves - the choice of test sieve (diameter and mesh) depends mainly
on the amount of sample and its particle size distribution. Optimal sieving time and
amplitude or speed wherein the settings for the sieving time and the optimal amplitude or
speed depend on the material to be sieved. Lastly are the sieving aids which are useful
in very fine samples that tend to adhere together. They are used to make the sample
sievable.

7. Conclusion
Based on the data presented shows that the size diameter of a particle has an
effect on the mean diameter of a particle in terms of length, surface & volume. Plotting
the data between the sizes of the particle versus the mass fraction of the material retained
in the screen, a bell shape curves was generated. This implies that this variable is not
directly proportional to each other because no linear relationship is evident between them.
Even though the data gathered shows the relationship of some variable; accuracy may
not be sure to be achieved. The inaccuracy may be due to the insufficient cleanliness of
the sieve.

9. 8. Recommendation
In this experiment, several precaution must be taken into consideration in order to
avoid and prevent errors to occur. The screen on the sieves should be carefully cleaned
in order to remove all grain sands. The stack of sieves on the Sieve Shaker must be
locked tidily to avoid them from moving away during shaking process. Ensure that all the
left over sand in each sieve is transferred to the container use in weighing process. The
area around digital scale balance must be cleaned first to get accurate readings and avoid
the environmental effects. Student also can use a soft bristle brush to gently wipe the
screen.


9. References
[1] Geankoplis, C.J. (2009) Principles of Transport Processes and Separation
Processes. 1
st
edition. Pearson Education South Asia PTE. LTD.

10. Web References
[1] Sieving - Definition & Process | Sieving Method Of Separation@byjus. (2017,
September 20). Retrieved March 10, 2018, from https://byjus.com/chemistry/sievi ng/
[2]Sieve Analysis. Retrieved March 10, 2018, from
https://www.retsch.com/news/details/news_detail/sieve-analysis
[3] Dishman, K. L. (2006, September 15). Sieving in Particle Size Analysis. Retrieved
March 10, 2018, from
http://onlinelibrary.wiley.com/doi/10.1002/9780470027318.a1514/abstract;jsessionid
=D1B3D0B2D22DB62438DADC0F0EDB41F0.f04t04