6
to amplifiers, which then have been connected to a mul-
tiplexer. Finally, the multiplexer is connected to the actual
microcontroller. The microcontroller has a Micro-USB
connector and can therefore be either used with a constant
electricity source or even with a conventional power pack.
To log the data, CoolTerm and Machinechat Jedi have
been used. Both programs enable data reading from the
microcontroller, thus Machinechat is a more sophisticated
IoT (Internet of Things) software that provides a virtual
accessible dashboard, where the user can look into process
logs and visualizations. Especially this is a certainly interest-
ing aspect for R &D projects, because the user could look
into live data from distance as long as there is an active
network connection in the laboratory or (underground)
test site.
SUMMARY
The results derived from both the in-situ and laboratory
investigations support the hypothesis than the placement
position and depth of heat-generating waste affects the spa-
tial thermal radiation and ratio of heat emitted into the
surrounding backfill or host rock.
Applying microcontrollers and modern software
allowed to log the data efficiently and visualized direct
changes in temperatures or heating patterns in real-time.
Moreover, this has proven that even economically efficient
setups can provide valuable data insights into rather com-
plicated processes.
The simultaneously conducted research project
“SAVER” proved that the actual creation of a trench on a
realistic scale can be executed with conventionally applied
and available underground mining equipment. In total, 2
trenches in 2 different test drifts with similar dimensions
have been created with a LHD and a road header attach-
ment. Thus, it was identified that operator skill and road
header diameter affect the accuracy of the final trench
dimensions. 2 real-life sized POLLUX HLW disposal con-
tainer dummies have been successfully emplaced within
the trenches and then backfilled. Trenching boosts the level
of static stability of the emplaced containers by acting as
an abutment against possible container movement due to
induced kinetic energy from slinger backfilling or the gravi-
tational weight of the backfill itself.
In the future, the experiments are supposed to be
repeated on a bigger scale and with a more sophisticated
logging and heating setup. Furthermore, numerical model-
ling with software such as FLAC3D would be desirable and
possibly helpful in order to gain a deeper understanding of
the 3D heat dissipation. With a high level of knowledge
regarding the overall spatial heat flow through the back-
fill and host rock, adjusting the trench depth could be a
possible tweak to optimize infrastructural aspects, such
as disposal drift distance or required overall underground
surface.
References
Alsalamin, I. (2023). Practical Model Approach for
Relationship between POLLUX Emplacement Position.
Freiberg: TU Bergakademie Freiberg .
GRS. (2012, Juni). Endlagerauslegung und -optimierung
-Bericht zum Arbeitspaket 6. Retrieved from https://
www.grs.de/sites/default/files/publications/GRS-281
_neu.pdf.
National Citizens’ Oversight Committee. (2024, April 15).
Was sind Wirts¬ge¬stei¬ne? Retrieved from https://www
.nationales-begleitgremium.de/DE/Endlagersuche
/GeologischeDaten/_docs/Was_sind_Wirtsgesteine
.html.
Schaarschmidt, L., Paschke, I., Freyer, D., &Mischo, H.
(2024). SAVER Project Report: Development of a matrix-
stabilized backfill concept with respect to container retriev-
ability -Phase I. Freiberg :TU Bergakademie Freiberg.
Table 1. Heating data from laboratory test phases A and C
(Alsalamin, 2023)
Phase A
(0% depth) [°C]
Phase C
(30% depth) [°C]
Sensor 1 200 204
Sensor 2 126 94
Sensor 3 80 65
Sensor 4 41 41
Sensor 5 32 33
to amplifiers, which then have been connected to a mul-
tiplexer. Finally, the multiplexer is connected to the actual
microcontroller. The microcontroller has a Micro-USB
connector and can therefore be either used with a constant
electricity source or even with a conventional power pack.
To log the data, CoolTerm and Machinechat Jedi have
been used. Both programs enable data reading from the
microcontroller, thus Machinechat is a more sophisticated
IoT (Internet of Things) software that provides a virtual
accessible dashboard, where the user can look into process
logs and visualizations. Especially this is a certainly interest-
ing aspect for R &D projects, because the user could look
into live data from distance as long as there is an active
network connection in the laboratory or (underground)
test site.
SUMMARY
The results derived from both the in-situ and laboratory
investigations support the hypothesis than the placement
position and depth of heat-generating waste affects the spa-
tial thermal radiation and ratio of heat emitted into the
surrounding backfill or host rock.
Applying microcontrollers and modern software
allowed to log the data efficiently and visualized direct
changes in temperatures or heating patterns in real-time.
Moreover, this has proven that even economically efficient
setups can provide valuable data insights into rather com-
plicated processes.
The simultaneously conducted research project
“SAVER” proved that the actual creation of a trench on a
realistic scale can be executed with conventionally applied
and available underground mining equipment. In total, 2
trenches in 2 different test drifts with similar dimensions
have been created with a LHD and a road header attach-
ment. Thus, it was identified that operator skill and road
header diameter affect the accuracy of the final trench
dimensions. 2 real-life sized POLLUX HLW disposal con-
tainer dummies have been successfully emplaced within
the trenches and then backfilled. Trenching boosts the level
of static stability of the emplaced containers by acting as
an abutment against possible container movement due to
induced kinetic energy from slinger backfilling or the gravi-
tational weight of the backfill itself.
In the future, the experiments are supposed to be
repeated on a bigger scale and with a more sophisticated
logging and heating setup. Furthermore, numerical model-
ling with software such as FLAC3D would be desirable and
possibly helpful in order to gain a deeper understanding of
the 3D heat dissipation. With a high level of knowledge
regarding the overall spatial heat flow through the back-
fill and host rock, adjusting the trench depth could be a
possible tweak to optimize infrastructural aspects, such
as disposal drift distance or required overall underground
surface.
References
Alsalamin, I. (2023). Practical Model Approach for
Relationship between POLLUX Emplacement Position.
Freiberg: TU Bergakademie Freiberg .
GRS. (2012, Juni). Endlagerauslegung und -optimierung
-Bericht zum Arbeitspaket 6. Retrieved from https://
www.grs.de/sites/default/files/publications/GRS-281
_neu.pdf.
National Citizens’ Oversight Committee. (2024, April 15).
Was sind Wirts¬ge¬stei¬ne? Retrieved from https://www
.nationales-begleitgremium.de/DE/Endlagersuche
/GeologischeDaten/_docs/Was_sind_Wirtsgesteine
.html.
Schaarschmidt, L., Paschke, I., Freyer, D., &Mischo, H.
(2024). SAVER Project Report: Development of a matrix-
stabilized backfill concept with respect to container retriev-
ability -Phase I. Freiberg :TU Bergakademie Freiberg.
Table 1. Heating data from laboratory test phases A and C
(Alsalamin, 2023)
Phase A
(0% depth) [°C]
Phase C
(30% depth) [°C]
Sensor 1 200 204
Sensor 2 126 94
Sensor 3 80 65
Sensor 4 41 41
Sensor 5 32 33