Ikelic - Alliance Digital Repository

COAL
selected power generation, C02 capture options,
and C02 disposal options were evaluated. The
most promising options will be selected for more
detailed appraisal as components of a number of
Full Fuel Cycles for power generation.
Four power generation schemes were studied:
- A
- A
- An
modern pulverized coal-fired plant
equipped with flue gas desulfurization
facilities and operating with a subcritical
high temperature steam cycle
(PF+FGD).
modern natural gas-fired combined
cycle in which gas is fired into gas tur
bines with a steam turbine also incor
porated into the cycle (GTCC).
Integrated Gasification Combined
Cycle (IGCC) in which a coal slurry is fed
to an oxygen-blown gasifier of the
entrained-flow type.
TABLE 1
- Power
generation based on a scheme of
burning pulverized coal in oxygen using
recycled to moderate the combus
C02
tion temperature (CO, Recycle). The
technology has not been extensively
demonstrated and must therefore be
regarded as Long Term.
The four schemes were selected to represent a
wide range of C02 concentrations and conditions
in the exhaust gas.
The studies concentrate on the overall impact of
capture processes (for specifically removing or
isolating C02)
on power generation. The com
bined power generation and scrubbing plant
should have a net output of 500 megawatts (e).
Using solvent absorption of from the flue
C02
gas, figures arrived at for the cost incurred per
tonne of C02 release to atmosphere avoided,
range from $16 to $87 per tonne (Table 1). They
do not include the cost of C02 liquefaction and
disposal.
CARBON DIOXIDE RELEASES AND COST OF AVOIDANCE
(Efficiencies as %LHV)
CO, IGCC
PF+FGD GTCC IQQC Recvcle Selexol
Reference Efficiency 40 52 42 33 42
Efficiency After Capture 29 42 28 30 36
CO Captured (%) 90 85 90 99 82
C02 in Product (%)
Cost Avoided C02 ($/tonne)
Power Cost (ref . mills/kWh)
99.2
35
49
99.4
55
35
99.8
87
53
99.9
16
78
96
23
53
Power cost (mills/kWh)
Specific Investment Cost ($/kW)
74 53 112 94 63
Reference Case 1,058 702 1,561 2,044 1,561
Removal Case 1,842 1,367 3,254 3,102 2,400
4-40
THE SYNTHETIC FUELS REPORT, JANUARY 1995