7
water and reagent settings that were benchmarked from the
prior work established a logical starting point.
The circuit was designed in a manner that the StackCell
module could be brought online or taken offline and return
the plant to prior operating conditions in the case of a cir-
cuit upset condition. This allowed the seamless ramp up
and onboarding of the StackCell circuit without disruption
of ongoing plant operation and production. The ramp up
period allowed for the operation and optimization of both
the StackCell circuit and the associated equipment that was
utilized to capture the StackCell product.
StackCell Circuit Performance
After the initial ramp up period, optimization of the circuit
was completed. A metallurgical sampling campaign was
initiated and is ongoing to ensure efficiency is maintained.
Table 1 contains the average product generated for the
installed StackCell circuit. The actual in-plant StackCell
performance matches closely when compared to the data
gathered from both bench and pilot testwork. The perfor-
mance of the StackCell circuit has met the expectations and
targets for the installation.
Table 1. Leer preparation plant ultrafine coal product
Specification
Product
Ash (%)
Standard
Deviation
6-Month Average Produced Product 6.79 0.37
SUMMARY AND CONCLUSIONS
The overall project and installation demonstrated the
ability to both effectively test and scale up a project from
laboratory to industrial installation. The bench scale test
work showed the initial potential recovery of additional
product while the pilot work validated that performance
and efficiency. The pilot work also aided in refining the
requirements for the ultimate equipment selection for the
industrial installation. The overall product that has been
captured from the circuit has generated great economic
value and has driven an increase in overall plant efficiency.
REFERENCES
[1] World Steel Association. (2024) “World Steel in
Figures 2024.”
[2] Critical Raw Materials Alliance. (2024) https://www
.crmalliance.eu/coking-coal.
[3] Hasanbeigi, A. and Springer, C. (2019) “How
Clean is the U.S. Steel Industry?” An International
Benchmarking of Energy and CO2 Intensities. San
Francisco CA: Global Efficiency Intelligence.
[4] Kohmuench, J, Yan, E, and Christodoulou, L (2012)
“Column and non-conventional flotation for coal
recovery: Circuitry, methods, and considerations”
Proceedings of the 2012 SME/PCMIA Annual Joint
Meeting, Pittsburgh, Pennsylvania.
[5] Kohmuench, J, Mankosa, M, and Luttrell, G (2007)
“Fine coal cleaning: A review of column flotation-
options and design considerations” Proceedings
of the 2007 SME/PCMIA Annual Joint Meeting,
Pittsburgh, Pennsylvania.
0
20
40
60
80
100
0 5 10 15 20 25 30
Product Ash (%)
Lab Release
Lab Kinetics
Industrial Sizing
Avg. Pilot Data
0
20
40
60
80
100
0 150 300 450 600 750
Flotaiton Residence Time (sec)
Lab Kinetics
Industrial Sizing
Avg Pilot Data
Figure 8. Summary of combustible recovery versus product
ash (top) and residence time (bottom) for StackCell scale-up
Combustible
Recovery
(%)
Combustible
Recovery
(%)
water and reagent settings that were benchmarked from the
prior work established a logical starting point.
The circuit was designed in a manner that the StackCell
module could be brought online or taken offline and return
the plant to prior operating conditions in the case of a cir-
cuit upset condition. This allowed the seamless ramp up
and onboarding of the StackCell circuit without disruption
of ongoing plant operation and production. The ramp up
period allowed for the operation and optimization of both
the StackCell circuit and the associated equipment that was
utilized to capture the StackCell product.
StackCell Circuit Performance
After the initial ramp up period, optimization of the circuit
was completed. A metallurgical sampling campaign was
initiated and is ongoing to ensure efficiency is maintained.
Table 1 contains the average product generated for the
installed StackCell circuit. The actual in-plant StackCell
performance matches closely when compared to the data
gathered from both bench and pilot testwork. The perfor-
mance of the StackCell circuit has met the expectations and
targets for the installation.
Table 1. Leer preparation plant ultrafine coal product
Specification
Product
Ash (%)
Standard
Deviation
6-Month Average Produced Product 6.79 0.37
SUMMARY AND CONCLUSIONS
The overall project and installation demonstrated the
ability to both effectively test and scale up a project from
laboratory to industrial installation. The bench scale test
work showed the initial potential recovery of additional
product while the pilot work validated that performance
and efficiency. The pilot work also aided in refining the
requirements for the ultimate equipment selection for the
industrial installation. The overall product that has been
captured from the circuit has generated great economic
value and has driven an increase in overall plant efficiency.
REFERENCES
[1] World Steel Association. (2024) “World Steel in
Figures 2024.”
[2] Critical Raw Materials Alliance. (2024) https://www
.crmalliance.eu/coking-coal.
[3] Hasanbeigi, A. and Springer, C. (2019) “How
Clean is the U.S. Steel Industry?” An International
Benchmarking of Energy and CO2 Intensities. San
Francisco CA: Global Efficiency Intelligence.
[4] Kohmuench, J, Yan, E, and Christodoulou, L (2012)
“Column and non-conventional flotation for coal
recovery: Circuitry, methods, and considerations”
Proceedings of the 2012 SME/PCMIA Annual Joint
Meeting, Pittsburgh, Pennsylvania.
[5] Kohmuench, J, Mankosa, M, and Luttrell, G (2007)
“Fine coal cleaning: A review of column flotation-
options and design considerations” Proceedings
of the 2007 SME/PCMIA Annual Joint Meeting,
Pittsburgh, Pennsylvania.
0
20
40
60
80
100
0 5 10 15 20 25 30
Product Ash (%)
Lab Release
Lab Kinetics
Industrial Sizing
Avg. Pilot Data
0
20
40
60
80
100
0 150 300 450 600 750
Flotaiton Residence Time (sec)
Lab Kinetics
Industrial Sizing
Avg Pilot Data
Figure 8. Summary of combustible recovery versus product
ash (top) and residence time (bottom) for StackCell scale-up
Combustible
Recovery
(%)
Combustible
Recovery
(%)