Environmental Engineering Reference
In-Depth Information
EP
3
is expressed per hour being a more practical scale for economics than per
second. This EP
3
function accounts for the earnings from the products, the cost
of the feed, as well as the capital costs:
in $ h
−1
EP
3
=
P
products
−
C
feed
−
C
CO
2
−
C
cap
,
h
P
products
=
P
liq
:
fuel
+
P
offgas
+
P
water
P
liq
:
fuel
= 3600
p
C
4+
φ
5
,
C
4+
P
offgas
= 3600
c
syngas
φ
5
,
H
2
+
+
p
offgas
φ
5
,
C
1
+
φ
5
,
CO
φ
5
,
C
2
+
φ
5
,
C
3
P
water
= 3600
p
H
2
O
φ
5
,
H
2
O
C
feed
= 3600
c
syngas
φ
1
,
total
C
CO
2
= 3600
c
CO
2
φ
5
,
CO
2
−
φ
1
,
CO
2
C
cap
,
h
=
ccf I
cap
=
t
prod
ð
Eq
:
7
:
17
Þ
The capital investment is built up of the sum of the investments in the process
blocks. The investment for a process block scales with the state of its technol-
ogy, as expressed by a relevant design parameter (
η
,
λ
), and the throughput
φ
with a power law. Both technology and throughput are scaled with respect
to a set of nominal conditions:
conð Þ
actual
seðÞ
actual
+
I
mið Þ
I
cap
=
I
+
I
actual
with
:
0
1
0
1
q
q
conð Þ
actual
φ
η
nom
η
conð Þ
actual
conð Þ
nom
@
A
@
A
I
=
I
conð Þ
nom
φ
0
1
0
1
q
q
seðÞ
actual
φ
λ
nom
λ
seðÞ
actual
=
I
seðÞ
nom
@
A
@
A
I
conð Þ
nom
φ
0
@
1
A
q
mið Þ
actual
φ
I
mið Þ
actual
=
I
mið Þ
ð
Eq
:
7
:
18
Þ
nom
mið Þ
nom
φ
The technology parameter for the conversion block is the degree of CO con-
version (
) serves a similar goal for
the separation block. The mixer block has no technology parameter assigned.
The structure of these equations properly reflects trends in investment costs
as a function of technology and throughput. Improvement in technology leads
to smaller investment costs for the same throughput.
η
), while the separation scaling factor (
λ
Search WWH ::
Custom Search