Ikelic - Alliance Digital Repository

OIL SHALE
native to severe hydrotreatment for the removal
of refractory aromatic nitrogen compounds from
hydrotreated shale oils. The US-Y zeolite shows
high selectivity toward amines and N
heterocycles and adsorbs them efficiently even in
the presence of large concentrations of saturated
and aromatic hydrocarbons.
The zeolite containing the adsorbed N
heterocycles is readily separated by gravitational
settling and regenerated for reuse by burning off
the adsorbed organics. The high nitrogen con
tent of the adsorbed organics may cause some
combustion of the
NO to be formed during
zeolite, so appropriate stack gas scrubbing may
be required (as it is for the ammonia and
hydrogen sulfide produced by hydrotreatment).
Because the N compounds constitute a very
small proportion of a mildly hydrotreated oil, it
would be more economic to sacrifice these com
pounds by zeolite adsorption and combustion
rather than to use the alternative procedure of
very severe hydrotreatment, which substantially
lowers the value and yield of total liquid products
through loss of aromaticity, cracking and coking.
####
GE PATENTS RADIO FREQUENCY IN SITU
RECOVERY METHOD
United States Patent 5,236,039 issued to
W. Edeistein et al., and assigned to General
Electric Company, describes a new method of
arranging electrodes for a radio-frequency, in situ
recovery
method for oil shale.
A system for extracting oil in situ from a deep
hydrocarbon bearing layer employs a master os
cillator for producing a fundamental frequency, a
plurality of radiofrequency (RF) heating
electrodes, and a matching network. The con
ductive electrodes are situated in a rectangular
pattern. Production wells are provided at the cen
ter of each rectangular pattern for collecting the
oU and producing it at the surface. The currents
among the electrode array uniformly
heat the oil-
2-15
rich layer in situ to pyrolysis. Oil reaches the
production wells by fracturing the hydrocarbon
bearing layer and creating permeable paths to
the production wells.
Figure 1 is a plan view showing the placement of
electrodes and producer wells as they appear in
situ, according to the tripiate pattern and a pat
tern according to the present invention.
Figure 2 is a graphical comparison of cumulative
oil recovery over time using a Thermal Conduc
tion (TC) apparatus versus using the RF process
to the present invention.
according
Figure 1 represents electrodes 19, 29 as solid
circles and producer wells 81 as open circles, in
a top plan view. The electrode rows are posi
tioned substantially
closer than a wavelength
apart, and the electrodes within each row are
positioned substantially
closer than the row-to-
row spacing. Typical values for distances within
FIGURE 1
WELL PATTERNS FOR
TRIPLATE CONFIGURATION
AND GE CONFIGURATION
TRI-PLATE DEVICE
+2V 0 +2V
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of
J...I.
M
PRESENT INVENTION
?V -V +V -V
0 0 Q
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THE SYNTHETIC FUELS REPORT, JANUARY 1995