334 XXXI International Mineral Processing Congress 2024 Proceedings/Washington, DC/Sep 29–Oct 3
water ice. The characteristics of the ejecta depend on the
size, velocity, and mechanical properties of the impacting
object and the distance from the impact to the PSR. Bigger
and faster impacts can deposit larger blocks of the lunar
surface struck by the meteor over great distance from the
point of contact. Once blocks of ejecta are exposed to the
Moon’s environment, they are subjected to degradation due
to thermal cycling and gardening. Figure 7 shows a variety
of lunar surface geology.
It is possible that PSR’s may have layered deposits that
include any of the geological forms shown in Figure 7. To
qualitatively assess the nature of layering, the age and size
of nearby impact craters should be considered. Large craters
that are younger than the PSR can potentially contribute to
the layered nature of the ice deposit.
EXTRACTION:
Two primary methods of extracting water from icy regolith
deposits in PSRs have been proposed, traditional excava-
tion and hauling of water bearing ore, and direct extraction
of water from the ore in situ. Many adaptations of tradi-
tional mining processes for excavation of water bearing ore
and delivery to a processing plant have been described in
the literature. A number of methods for direct extraction
of water from the icy regolith by localized heating of the
deposit have also been proposed. Both these methods must
consider the various physical states of water on the lunar
surface and in PSRs. Figure 8 illustrates a potential water
extraction process based on manipulation of temperature
and pressure.17
The extraction process shown in Figure 8 assumes the
following unit operations. The process begins with extract-
ing water bearing ore and placing it in a pressure tight
container at a temperature of 70K and a pressure equiva-
lent to a hard vacuum. The temperature of the container
is then raised from 70K to 375K. This temperature, which
is close to the highest temperature on the lunar surface, is
arbitrarily selected for this example. At a temperature of
375K the water has sublimed from a solid to a vapor state.
In this state the water vapor may be separated from other
volatile gases extracted from the pressure tight container.
The extracted water vapor is then pressurized up to a few
hundred kPa where it becomes liquid and can then be fur-
ther processed by electrolysis into hydrogen and oxygen.
It is important to note that water bearing ore extracted
from within a PSR and transported out of this shadowed
Figure 6. Lunar dust affects surface operations
Figure 7. Lunar surface geology16
water ice. The characteristics of the ejecta depend on the
size, velocity, and mechanical properties of the impacting
object and the distance from the impact to the PSR. Bigger
and faster impacts can deposit larger blocks of the lunar
surface struck by the meteor over great distance from the
point of contact. Once blocks of ejecta are exposed to the
Moon’s environment, they are subjected to degradation due
to thermal cycling and gardening. Figure 7 shows a variety
of lunar surface geology.
It is possible that PSR’s may have layered deposits that
include any of the geological forms shown in Figure 7. To
qualitatively assess the nature of layering, the age and size
of nearby impact craters should be considered. Large craters
that are younger than the PSR can potentially contribute to
the layered nature of the ice deposit.
EXTRACTION:
Two primary methods of extracting water from icy regolith
deposits in PSRs have been proposed, traditional excava-
tion and hauling of water bearing ore, and direct extraction
of water from the ore in situ. Many adaptations of tradi-
tional mining processes for excavation of water bearing ore
and delivery to a processing plant have been described in
the literature. A number of methods for direct extraction
of water from the icy regolith by localized heating of the
deposit have also been proposed. Both these methods must
consider the various physical states of water on the lunar
surface and in PSRs. Figure 8 illustrates a potential water
extraction process based on manipulation of temperature
and pressure.17
The extraction process shown in Figure 8 assumes the
following unit operations. The process begins with extract-
ing water bearing ore and placing it in a pressure tight
container at a temperature of 70K and a pressure equiva-
lent to a hard vacuum. The temperature of the container
is then raised from 70K to 375K. This temperature, which
is close to the highest temperature on the lunar surface, is
arbitrarily selected for this example. At a temperature of
375K the water has sublimed from a solid to a vapor state.
In this state the water vapor may be separated from other
volatile gases extracted from the pressure tight container.
The extracted water vapor is then pressurized up to a few
hundred kPa where it becomes liquid and can then be fur-
ther processed by electrolysis into hydrogen and oxygen.
It is important to note that water bearing ore extracted
from within a PSR and transported out of this shadowed
Figure 6. Lunar dust affects surface operations
Figure 7. Lunar surface geology16