8
IV. DISCUSSION
A. Comparison of Experimental Result and the Soudan
Mine experiment
Comparing the results of this experiment to the Soudan
mine experiment result, it can clearly be noticed that in this
experiment APTsorb had a very fast running time with a
very low adsorption capacity of zinc. This premised the con-
clusion that it wouldn’t be good for the design of a future
RSS plant. Nevertheless, APT works better under specific
preset conditions of pH and etc. For this lab work, there
was no chemically or physically enhanced condition for the
APTsorb. Also, in the Soudan mine experiment APTsorb
was efficient for the removal of copper and cobalt with pre-
vious smallscale pilot tests showing that the media could
remove both suspended and dissolved copper from mine
drainage (Eger, Paulson and Green., 2008). Specialized
pressurized tank were designed at the industrial level to
enhance the performance of the peat media.
B. Comparison of the Results
In this experiment we realize that each material
shows different suitability in terms of zinc sorption.
The APTsorb material has the lowest capacity. The
Activated coke from natural residues shows the second
highest capacity. The Charred fermentation residues
from the University has the highest capacity value and
means it is very well suited for the sorption of zinc and
in a continuous form clearly exceeded the benchmark
value even though the experiment didn’t end due to
time constraints. Generally, the modifications made
in the material B and C through the increase in their
surface area by grinding proved to help in their adsorp-
tion. With respect to the breakthrough curves of the
materials, the experiment C shows a better curve that is
steeper. (Table 5)
C. pH and Eh Values of the Experiment
Throughout the experiment we noticed an increase in
pH For the Activated coke and Biochar, a reason for
the increase in the pH can be attributed to the alkaline
ash content of the materials. Also, at the initial phases
where distilled water was pumped through the column,
a very alkaline measurement was recorded. Throughout
the effluent pH values were higher than the initiating
pH values. Standard zinc will always be in a reduced
form and the Eh values showed throughout the experi-
ment. The Eh values are very high whenever the Zinc
concentration at exhaustion exceeded the initial zinc
concentration indicating desorption. The Eh values at
Table 5: Comparison of the results from experiment and previous work done by Lisa Maria
Johnke
Material
Sorption
(mg/g) Capacity
Sorption
(meq/g) Capacity Source
APTsorb 0.23 Lisa
Maria
Johnke
Activated Coke 0.61 See above
Charred fermentation residue 1.55 See above
APTsorb 0.250 0.01 This thesis work
Activated Coke 17.40 0.53 See above
Charred fermentation residues 55.263 1.69 See above
Figure 12.
IV. DISCUSSION
A. Comparison of Experimental Result and the Soudan
Mine experiment
Comparing the results of this experiment to the Soudan
mine experiment result, it can clearly be noticed that in this
experiment APTsorb had a very fast running time with a
very low adsorption capacity of zinc. This premised the con-
clusion that it wouldn’t be good for the design of a future
RSS plant. Nevertheless, APT works better under specific
preset conditions of pH and etc. For this lab work, there
was no chemically or physically enhanced condition for the
APTsorb. Also, in the Soudan mine experiment APTsorb
was efficient for the removal of copper and cobalt with pre-
vious smallscale pilot tests showing that the media could
remove both suspended and dissolved copper from mine
drainage (Eger, Paulson and Green., 2008). Specialized
pressurized tank were designed at the industrial level to
enhance the performance of the peat media.
B. Comparison of the Results
In this experiment we realize that each material
shows different suitability in terms of zinc sorption.
The APTsorb material has the lowest capacity. The
Activated coke from natural residues shows the second
highest capacity. The Charred fermentation residues
from the University has the highest capacity value and
means it is very well suited for the sorption of zinc and
in a continuous form clearly exceeded the benchmark
value even though the experiment didn’t end due to
time constraints. Generally, the modifications made
in the material B and C through the increase in their
surface area by grinding proved to help in their adsorp-
tion. With respect to the breakthrough curves of the
materials, the experiment C shows a better curve that is
steeper. (Table 5)
C. pH and Eh Values of the Experiment
Throughout the experiment we noticed an increase in
pH For the Activated coke and Biochar, a reason for
the increase in the pH can be attributed to the alkaline
ash content of the materials. Also, at the initial phases
where distilled water was pumped through the column,
a very alkaline measurement was recorded. Throughout
the effluent pH values were higher than the initiating
pH values. Standard zinc will always be in a reduced
form and the Eh values showed throughout the experi-
ment. The Eh values are very high whenever the Zinc
concentration at exhaustion exceeded the initial zinc
concentration indicating desorption. The Eh values at
Table 5: Comparison of the results from experiment and previous work done by Lisa Maria
Johnke
Material
Sorption
(mg/g) Capacity
Sorption
(meq/g) Capacity Source
APTsorb 0.23 Lisa
Maria
Johnke
Activated Coke 0.61 See above
Charred fermentation residue 1.55 See above
APTsorb 0.250 0.01 This thesis work
Activated Coke 17.40 0.53 See above
Charred fermentation residues 55.263 1.69 See above
Figure 12.