Adsorption - Introduction to Carbon Capture and Sequestration - page 272

Table 6.6.2 Comparison of GHG emissions in 2050 without CCS and with CCS using
MEA or MOFs

GHG emissions in 2050
(Gt CO 2 per year)

Cumulative emissions
2010-2050 (Gt CO 2 )

No
CCS

MEA
CCS

MOF
CCS

No
CCS

MEA
CCS

MOF
CCS

Plant stack emissions 1.97 0.25 0.24 86.8 59.0 58.8

Coal mining and
transport

0.21 0.27 0.25 9.2 10.1 9.9

Plant infrastructure 0.01 0.02 0.02 0.2 0.3 0.4

Capture media and
storage

0 0.02 0.03 0 0.3 0.6

CO 2 transport and
storage

0 0.03 0.03 0 0.6 0.6

Total 2.20 0.59 0.58 96.2 70.4 70.2
Estimated base-case GHG emissions in 2050 (Gt CO 2 per year) and cumulative GHG emissions from
2010 to 2050 (Gt CO 2 ) from the USA coal-fired power fleet without CCS and with CCS using MEA
or MOF capture technology. Data from Sathre and Masanet [6.39].

only a fraction of the total costs. If a new material performs better, then
these additional expenses can be compensated by energy savings.
Given the fact that there are very little real process data for
Mg- MOF-74, the predictions of these costs estimates have many uncer-
tainties. The uncertainties are displayed in a so-called tornado graph,
Figure 6.6.2 . This fi gure ranks all the parameters that are in the cost
model in the order in which the uncertainty changes the cost estimate.
The largest uncertainties are in the recycling time, the life span of a MOF,
and the energy needed to regenerate a MOF.
The capture/regeneration cycle time is the time it takes to adsorb a
bed with CO 2 and the subsequent purge. As the amount of fl ue that we
need to process per hour is fi xed, a long recycle time means that we have
to operate more beds in parallel. In the calculations of Sathre and
Masanet, the uncertainties in this recycling time result in the largest con-
sequence on the cost, and further research would be needed to more
precisely estimate these cycles times. In addition, these results pose
some interesting questions. Will this time be faster if we operate this
process as a pressure swing operation versus a temperature swing