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Abstract

Obiectivul principal al acestui studiu a constat în compararea ciclului de viaţă al combustibililor fosili (cărbune, gaze naturale şi petrol), în scopul de a evalua impactul global asupra mediului inconjurator. În acest sens, a fost analizată producţia de energie pe bază de combustibili fosili utilizând cele mai bune tehnologii energetice disponibile. Metodologia utilizată pentru evaluarea impactului global asupra mediului înconjurător este Analiza Ciclului de Viaţă. Metoda utilzată a permis identificarea poluanţilor generaţi în fiecare etapă: extracţie, tratare, transport şi de ardere, precum şi identificarea principalelor clase de impact, conform analizei de inventar. The main objective of this study is to compare the life cycle of fossil fuel (coal, natural gas and oil) in order to assess the overall environmental impact. In this respect it was analyzed the fossil fuels energy production based on the best available energy technologies for each fuel. The methodology used in order to evaluate the total environmental impact was Life Cycle Analysis. The method allowed on one side the identification of the pollutants generated in each stage: extraction, treatment, transportation and combustion, and on the other side identification of the main classes of impact according the pollutants inventory.
U.P.B. Sci. Bull., Series C, Vol. 71, Iss. 1, 2010 ISSN 1454-234x
LIFE CYCLE IMPACT ASSESSMENT OF FOSSIL FUELS
Cristian DINCĂ
1
, Adrian BADEA
2
, Tiberiu APOSTOL
3
Obiectivul principal al acestui studiu a constat în compararea ciclului de
viaţă al combustibililor fosili (cărbune, gaze naturale şi petrol), în scopul de a
evalua impactul global asupra mediului inconjurator. În acest sens, a fost analizată
producţia de energie pe bază de combustibili fosili utilizând cele mai bune
tehnologii energetice disponibile. Metodologia utilizată pentru evaluarea impactului
global asupra mediului înconjurător este Analiza Ciclului de Viaţă.
Metoda utilzată a permis identificarea poluanţilor generaţi în fiecare etapă:
extracţie, tratare, transport şi de ardere, precum şi identificarea principalelor clase
de impact, conform analizei de inventar.
The main objective of this study is to compare the life cycle of fossil fuel
(coal, natural gas and oil) in order to assess the overall environmental impact. In
this respect it was analyzed the fossil fuels energy production based on the best
available energy technologies for each fuel. The methodology used in order to
evaluate the total environmental impact was Life Cycle Analysis.
The method allowed on one side the identification of the pollutants generated
in each stage: extraction, treatment, transportation and combustion, and on the
other side identification of the main classes of impact according the pollutants
inventory.
Keywords: LCA, fossil fuels, multi-criteria analysis
1. Introduction
According to estimates the International Energy Agency (IEA), centralized
in the annual World Energy Outlook, fossil fuels will account for 84 % growth in
energy demand in the period 2005-2030. Reflecting this trend, the share of coal in
global energy demand will increase from 25% to 28%. Natural gas, a fuel with a
much lower level of pollution than coal, will register a moderate growth increase
in use worldwide, from 21% to 22%, while nuclear power, which doesn’t generate
carbon dioxide emissions, will be used in a lesser extent, representing 5% of
global demand, comparing to 6 % at the 2005. Although global medium term, the
share of coal in electricity production increases, in Romania it lasts the same
amount as in the year 2007. Unlike coal, it seems that, at least in Romania, natural
1
Lecturer, Power Engineering Faculty, University POLITEHNICA of Bucharest, Romania
2
Prof., Power Engineering Faculty, University POLITEHNICA of Bucharest, Romania,
a_badea@rectorat.pub.ro
3
Prof., Power Engineering Faculty, University POLITEHNICA of Bucharest, Romania
116 Cristian Dincă, Adrian Badea, Tiberiu Apostol
gas demand will grow in the near future. The opposite is oil whose request for the
production of electricity will drop in coming years.
The life cycle assessment (LCA) is a tool utilized for evaluating the
environmental impact on the assembly of activities associated with a product,
service, process or production chain, starting from the raw material extraction up
to the last waste elimination [1].
According to the data presented in table 1, the share of fossil fuels will
continue to be high in 2020, as well. The absolute value for coal will increase, that
of natural gas will remain practically constant, while oil energy will register a
major decrease.
Table 1
Production of electrical energy in 2007 and electrical energy production forecast
at the level of the year 2020 [2]
Indicators 2007 achieved 2020 forecast
m.u. TWh % TWh %
Electrical energy production
of which:
61.68 100 100 100
Total thermal, of which: 38 61.6 45.9 45.9
- Coal 20.86 54.9 34.9 76.0
- Natural gas 9.61 25.3 9.5 20.7
- Oil 7.53 19.8 1.5 3.3
Hydro 15.97 25.9 32.5 32.5
Nuclear 7.71 12.5 21.6 21.6
2. Life cycle of fossil fuels
The analyzed chains of electrical energy production are the following: the
coal, natural gas and oil life cycle.
For the analyzed chains, the following analysis stages have been
considered: extraction, treatment, transport and combustion [3].
Within the analysis the following study hypotheses have been formulated:
The electrical energy production solutions by each type of fuel have been:
For coal, a technical solution consisting of circulating fluidized bed
combustion with supercritical parameters + combined cycle power plant,
with 40 % efficiency has been chosen. The coal utilized is hard coal. As a
result of the calculations based on the chosen coal composition, there
resulted a low heating value of 27,000 [kJ/kg].
For natural gas, the technical solution of the gas-steam combined cycle
with 55% efficiency has been selected. The gas that was used had a low
heating value of 50,000 [kJ/kg].
For oil, the technology considered for producing energy is boiler
combustion at atmospheric pressure + steam turbine. The low heating
Life cycle impact assessment of fossil fuels 117
value used in this paper is 43 100 kJ/kg. The efficiency considered for the
electrical energy production along this chain is 45 % [4].
Own energy consumption during the different life cycle stages is covered on
the basis of the respective fuel by each chain.
The energy solutions used have not been equipped with flue gas treatment
equipment not to disadvantage a certain energy chain.
The considered efficiencies for each life cycle stage have been [3,4]:
For coal (co): extraction (
η
ex
=75%), treatment (
η
tr
=95%), transport
(
η
tp
=85%), combustion (
η
cb
=40%);
For natural gas (ng): extraction (
η
ex
=90%), treatment (
η
tr
=95%),
transport (
η
tp
=90%), combustion (
η
cb
=55%) ;
For oil (o) : extraction (
η
ex
=90%), treatment (
η
tr
=95%), transport
(
η
tp
=90%), combustion (
η
cb
=45 %).
These values were used in the LCA methodology, but their interpretation must be
done with caution.
The average transport distance that has been considered in the case of natural
gas and oil was 450 km, and in the case of coal, 100 km, respectively.
Figure 1 presents the field of study for each chain.
After establishing the 1 TWh functional unit and the efficiencies of the
stages, starting from the low heating value of each fuel, the necessary amount of
fuel has been calculated by each stage and functional unit (FU). The reference unit
(RU) in this study represents the amount of fuel necessary during each stage for
producing 1 TWh of electrical energy. The emissions generated by the functional
unit have been updated at the functional unit with the equation 1.
Fig.1. Field of study for each chain.
1 TWh
COMBUSTI
ON
COMBUSTI
ON
COMBUSTI
ON
TRANSPOR
T
TRANSPOR
T
TRANSPOR
T
TREATME
NT
TREATME
NT
TREATME
N
T
EXTRACTI
ON
EXTRACTI
ON
EXTRACTI
ON
M
cb
=332*10
6
kg
M
tp
=390*10
6
kg
M
tr
=411*10
6
kg
M
ex
=548*10
6
kg
M
cb
=131*10
6
kg
M
tp
=146*10
6
kg
M
tr
=154*10
6
kg
M
ex
=171*10
6
kg
M
cb
=186*10
6
kg
M
tp
=206*10
6
kg
M
tr
=217*10
6
kg
M
ex
=241*10
6
kg
η
cb
=55
η
t
p
=90
η
tr
=95
η
ex
=90
η
cb
=45 %
η
t
p
=90 %
η
tr
=95
η
ex
=90
η
cb
=40
η
t
p
=85
η
tr
=95
η
ex
=75
118 Cristian Dincă, Adrian Badea, Tiberiu Apostol
,RUEE
ir
= [g/TWh]. (1)
Where:
E
r
– recalculated pollutant emission by functional unit;
E
i
– initial emissions collected during the inventory stage, in g/kg of fuel;
RU - reference unit specific to each life cycle stage, in kg_fuel / TWh.
Within the inventory analysis, data on the generated environmental
polluting emissions by each life cycle stage have been gathered, and on the basis
of the inventoried pollutants, the classes have been identified.
3. Results of the analyzed chain inventory analysis
The following observations can be made on the emissions generated over
the coal chain (table 2) during the entire life cycle [5]:
From the quantitative point of view, the generated air emissions exceed by far
the emissions polluting the water and soil ecosystems. The main pollutants
generated over the coal life cycle are: CO
2
=816,097 t/FU, dust particles under
10 μm (PM
10
=7,364 t/FU), SO
2
=5,360 t/FU, NO
2
=2,680 t/FU and CH
4
=730
t/FU. Although the other pollutant values are insignificant, it is nevertheless
necessary to develop the impact analysis for determining their environmental
impact.
As concerns the share of pollutants by each stage of the life cycle, the
following aspects should be mentioned:
Carbon dioxide: of the total emissions, during the combustion stage,
approx. 794 kt/FU have been generated, representing about 97%. The next
stage from point of view of its share is transport, generating about 14
kt/UF, representing approximately 2% of the total CO
2
emissions. During
the treatment and extraction stage, the share of CO
2
emissions within the
total emissions is 0.4%, and 0.6%, respectively.
Dust has been almost entirely generated (99.7%) during the combustion
stage.
Sulfur dioxide: during the combustion stage approximately 5.2 kt/FU
representing about 97% of the total SO
2
emissions, have been generated.
During the transport stage about 1.5% is generated, while the share of SO
2
emissions does not surpass 1% during the extraction and treatment stages.
Nitrogen dioxide: As for the other pollutants, the combustion stage
generates the highest share of NO
x
emissions, about 93%. During the other
stages the shares are insignificant, except for the transport stage when the
percentage of NO
x
emissions generated is 5.5%.
Methane: In comparison with other pollutants, in the case of methane the
extraction stage generates the highest amount of about 60%, followed by
Life cycle impact assessment of fossil fuels 119
the treatment stage generating 40%. The combustion and transport stages
have insignificant emission methane values.
As in the case of the coal chain, the natural gas chain (table 3) registers the
highest values of emissions in the air ecosystem [6]. The main pollutants
generated over the natural gas life cycle are: carbon dioxide (CO
2
=437,909
t/FU), methane (CH
4
=3,740 t/FU), nitrogen dioxide (NO
2
=561 t/FU), carbon
monoxide (CO=283 t/FU), sulfur dioxide (SO
2
=275 t/FU);
Relating to the share of pollutants within each stage of the life cycle the
following aspects are worth-mentioning:
Carbon dioxide: of the total emissions, approximately 371 kt/FU are
generated during the combustion stage, representing about 85%. The
stages that follow, from the point of view of their share, are the extraction
share generating 9% and the treatment stage with 6%. The transport stage
has insignificant values of CO
2
emissions.
Methane: is mainly generated during the extraction, 1,664 t/FU (44.5%),
treatment 1,111 t/FU (29.7%) and transport 920 (24.6%) stages, the
methane emissions generated during the combustion stage being
insignificant.
For nitrogen dioxide, the shares are the following: extraction (49.7%),
treatment (33.2%), combustion (16.9%), the transport stage being the least
polluting.
Carbon monoxide: the stage that has the highest share relating to CO
emissions is extraction (54%), followed by the treatment stage (36%). The
combustion and transport stages have the following shares: 9.5% and
0.5%, respectively.
As concerns sulfur dioxide, the extraction and treatment stages are mainly
responsible for generating this pollutant amounting to 59.4% and 39.7%,
respectively. During the combustion stage, SO
2
emissions do not surpass
1% of the total SO
2
emissions.
In the case of oil life cycle, table 4 presents the highest values of emissions in
the air ecosystem [6]. The main pollutants generated over the oil chain are:
carbon dioxide (CO
2
=919,000 t/FU), methane (CH
4
=163 t/FU), nitrogen
dioxide (NO
2
=940 t/FU), carbon monoxide (CO=610 t/FU), sulfur dioxide
(SO
2
=1,700 t/FU) and dust 104 t/FU;
Relating to the share of pollutants within each stage of the life cycle the
following aspects are worth-mentioning:
Carbon dioxide: of the total emissions, about 860 kt/FU are generated
during the combustion stage, representing about 93%. The stages that
follow, from the point of view of their share, are the extraction and
treatment with about 3 %. The transport stage has insignificant values of
CO
2
emissions.
120 Cristian Dincă, Adrian Badea, Tiberiu Apostol
Methane: is mainly generated during the extraction, 91 t/FU (55.5%), and
combustion stage 35 t/FU (21 %). In the treatment and transport stage the
methane emissions are 19 t/FU (12 %).
Table 2
Pollutants corresponding to the coal life cycle (t/FU)
Table 3
Pollutants corresponding to the natural gas life cycle(t/FU)
Natural gas
Extraction Treatment Transport Combustion Total
Air
CO
2
39,596 26,402 440 371,471 437,909
NO 12 7.7 14 8.7 42.4
CO 153 102 1.4 27 283.4
SO
2
163 109 0.648 1.9 274.5
NH
3
0 0 0.336 21 21.3
CH
4
1,664 1,111 920 45 3,740
NO
2
279 186 0.570 95 560.6
N
2
O 0.345 0.231 0.004 0 0.580
Dust (PM
10
) 13 8.2 0 62 83.2
Formaldehyde (CH
2
O) 0 0 0 8.6 8.6
Water
DCO 14 55 0 0 69
Phenyl chloride 0 0 0 0.005 0.005
Coal
Extraction Treatment Transport Combustion Total
Air
CO
2
4,570.22 3,101.67 14,036.86 794,388.26 816,097.01
CO 5.4 3.6 101 156 266
SO
2
34.31 22.52 76.12 5,227.69 5,360.64
NH
3
59 39 0.1 0.1 98.2
CH
4
433.92 289.10 0.73 6.79 730.54
NO
2
22.78 15.28 147.69 2,494.30 2,680.05
N
2
O 0.6 0.4 0.2 3.2 4.4
Dust (PM
10
) 5.90 0.51 14.74 7,343.82 7,364.96
Mercury 0 0 0 0.037 0.037
Molybdenum 0 0 0 0.038 0.038
Nickel 0 0 0 0.060 0.060
Water
Phenol 3.01E-06 2.007E-06 6.67E-10 1.9143E-05 2.42E-05
NH
4
10 6.7 0 0 16.7
COD 0.685 0.457 0 0.066 1.208
Agricultural soil
Barium 0 0 0 0.437 0.437
Copper 0 0 0 0.114 0.114
Nickel 0 0 0 0.156 0.156
Vanadium 0 0 0 0.317 0.317
Life cycle impact assessment of fossil fuels 121
For nitrogen dioxide, the shares are the following: extraction (8 %),
treatment (4 %), combustion (87 %), the transport stage being the least
polluting.
Carbon monoxide: the stage that has the highest share relating to CO
emissions is combustion (44%), followed by the extraction stage (32 %).
The treatment and transport stages have the following shares: 19 % and 6
%, respectively.
As concerns sulfur dioxide, the combustion stage is mainly responsible for
generating this pollutant amounting to 71 %. The extraction and transport
stage presents 13 % and 10 % respectively. During the treatment stage,
SO
2
emissions do not surpass 6 % of the total SO
2
emissions.
Table 4
Pollutants corresponding to the oil life cycle(t/FU)
Oil
Extraction Treatment Transport Combustion Total
Air
CO
2
30,301 28,399 2,200 858,070 918,970
NO 16 9.65 3 87 115.65
CO 192.70 116 34.7 266.9 610.3
SO
2
224.01 91.9 176.83 1207.1 1,699.84
NH
3
0 0 7.52 206.24 213.76
CH
4
90.91 18.30 19.4 35.12 163.73
NO
2
74.60 37.60 13.84 814.07 940.11
N
2
O 0.80 0.5 0.4 23 24.7
Dust (PM
10
) 13.50 3.4 0 88 104.9
Formaldehyde
(CH
2
O)
0 0 0 18.57148572 18.571
Water
DCO 18.84 77.7 0 0 96.54
Phenyl chloride 0 0 0 0.007 0.007
Agricultural soil
Lead 0.05 3.92 0.028 0.00017 3.998
4. Impact analysis
Based on the pollutants inventoried during the inventory analysis, the
following impact classes have been identified: ADP – Abiotic depletion potential,
GWP – Global warming potential, AP – Acidification potential, POCP –
Photochemical ozone creation potential, EP-Eutrophication, HTP – Human
Toxicity Potential, FAETP – Freshwater aquatic ecotoxicity potential, MAETP –
Marine aquatic ecotoxicity potential, TETP- Terrestrial ecotoxicity potential [7].
The impact indicators have been calculated by means of the relationships
given in table 5. The legend is given below the table.
122 Cristian Dincă, Adrian Badea, Tiberiu Apostol
Tables 6, 7 and 8 present a comparison between the impact indicators
separately calculated for each stage of the life cycle (coal, natural gas and oil) and
by the overall life cycle.
Table 5
Quantification of impact indicators [7, 8]
Impact class
Pollutan
ts
Calculation relationship
Used notations
and values
“Abiotic depletion
potential”
[kg antimony eq./kg
emission]
-
i
mADPADP
i
i
=
ADP
oil
=0,0201
ADP
natural
gas
=0,0187
ADP
coal
=0,013
4
“Global warming
potential”
[kg CO
2
eq. /kg
emmission]
CO
2
,
CH
4
,
N
2
O
i
mGWPGWP
i
i
=
GWP
CO2
=1
GWP
CH4
=21
GWP
N2O
=310
“Acidification
potential”
[kg SO
2
eq./kg
emmission]
SO
2
,
NH
3
,
NO
2
i
mAPAP
i
i
=
AP
SO2
=1,2
AP
NH3
=1,6
AP
NO2
=0,5
“Photochemical ozone
creation potential”
[kg ethene eq./kg
emmission]
CO,
SO
2
,
CH
4
,
CH
2
O,
NO
2
i
mPOCPPOCP
i
i
=
POCP
CO
=0,027
POCP
SO2
=0,04
8
POCP
CH4
=0,00
6
POCP
CH2O
=0,5
19
POCP
NO2
=0,02
8
“Eutrophication
potential”
[kg phosfate eq./kg
emmission]
NO,
NH
3
,
NO
2
,
COD,
NH
4
i
mEPEP
i
i
=
EP
NO
=0,200
EP
NH3
=0,350
EP
NO2
=0,130
EP
COD
=0,022
EP
N
H4
=0,350
“Human toxicity
potential”
[kg 1,4 dichlorbenzene
eq./kg emmission]
SO
2
,
NH
3
,
NO
2
,
Praf,
CH
2
O,
Pb,
Fenol,
HCl, HF
etc
icom
i com
icom
mHTPHTP
,,
=
HTP
SO2
=0,096
HTP
NH3
=0,100
HTP
NO2
=1,200
HTP
Praf
=0,820
HTP
CH2O
=0,83
0
HTP
Pb
=3300
HTP
Fenol
=0,520
HTP
HCl
=0,500
HTP
HF
=94
“Freshwater aquatic
ecotoxicity potential”
[kg 1,4 dichlorbenzene
eq./kg emmission]
CH
2
O,
Pb,
Fenol,
HF etc
icom
i com
icom
mFAETPFAETP
,,
=
FAETP
CH2O
=8,
3
FAETP
pb
=6,5
FAETP
Fenol
=1,
5
Life cycle impact assessment of fossil fuels 123
Impact class
Pollutan
ts
Calculation relationship
Used notations
and values
FAETP
HF
=4,6
“Marine aquatic
ecotoxicity potential”
[kg 1,4 dichlorbenzene
eq./kg emmission]
CH
2
O,
Pb,
Fenol,
HF etc
icom
i com
icom
mMAETPMAETP
,,
=
MAETP
CH2O
=1
,6
MAETP
pb
=750
MAETP
Fenol
=0,
056
MAETP
HF
=52
“Terrestrial ecotoxicity
potential”
[kg 1,4 dichlorbenzene
eq./kg emmission]
CH
2
O,
Pb,
Fenol,
HF etc
icom
i com
icom
mTETPTETP
,,
=
TETP
CH2O
=0,9
40
TETP
Pb
=33
TETP
HF
=0,003
The legend:
AP
i
– acidification potential of i substance emitted in the air;
POCP
i
– photochemical polluting potential of emitted i substance;
EP
i
– eutrophication potential of emitted i substance;
HTP
icom,i
– potential of human toxicity of i substance emitted in a certain compartment;
FAETP
icom,i
– ecotoxicity potential on fresh water of a i substance emitted in a certain
compartment;
MAETP
icom,i
– ecotoxicity potential on salt water of i substance emitted in a certain compartment;
m
i
– amount of i substance emitted in the respective compartment
TETP
icom,i
– ecotoxicity potential on the terrestrial systems of i substance emitted in a certain
compartment;
com=compartment (air, fresh water, salt water, agricultural soil, industrial soil);
a
com,i
= amount of i substance emitted in the respective compartment [kBq]
m
i
for ADP– quantity of resource i used;
m
i
for GWP, AP, POCP, EP– amount of i substance emitted
m
i
for HTP, FAETP, MAETP, TETP– amount of i substance emitted in the respective
compartment
Table 6
Impact indicators for the coal chain
Impact indicators
Stages
Extraction Treatment Transport Combustion Total
ADP [t Sb eq.] 6,527 0 0 0 6,527
GWP [t CO
2
eq.] 17,288 11,588 17,638 994,045 1,040,558
AP [t SO
2
eq.] 161 106 207 9,400 9,873
POCP [t ethene eq. ] 6 4 12 405 428
EP [t PO
4
3-
eq.] 28 19 24 405 476
HTP [t 1,4 DCB eq.] 50 30 246 33,681 34,007
FAETP [t 1,4 DCB eq.]
0 0 0 680 680
MAETP [t 1,4 DCB
eq.]
0 0 0 10,021 10,021
TETP [t 1,4 DCB eq.] 0 0 0 219 219
124 Cristian Dincă, Adrian Badea, Tiberiu Apostol
Table 7
Impact indicators for the natural gas chain
Impact indicators
Stages
Extraction Treatment Transport Combustion Total
ADP [t Sb eq.]
3,192 0 0 0 3,192
GWP [t CO
2
eq.]
74,639 49,809 19,765 372,418 516,631
AP [t SO
2
eq.]
335 223 2 83 643
POCP [t ethene eq. ]
22 15 6 6 49
EP [t PO
4
3-
eq.]
39 27 3 21 90
HTP [t 1,4 DCB eq.]
468 12,157 5 175 12,805
FAETP [t 1,4 DCB eq.]
0 22 0 71 93
MAETP [t 1,4 DCB eq.]
353 38,983 12 15 39,363
TETP [t 1,4 DCB eq.]
1 110 0 8 119
Based on the calculated impact indicators, a comparative analysis of the three
energy chains by each impact class is presented.
On the basis of the results obtained for the impact analysis, the following
conclusions can be drawn:
From the point of view of the “depletion of natural resources (abiotic)”
impact indicator, the coal chain has the highest value (6,527 t Sb eq.) against the
value registered for the natural gas chain (3,192 t Sb eq.). The corresponding
value of the oil chain is 4,848 t Sb eq..
By analyzing the „human toxicity” impact indicator, we can draw the
following conclusions: the coal chain has the highest value (approximately 34,000
t 1,4 DCB eq.) especially due to the pollutants generated during the combustion
stage, such as arsenic (51%), dust (22%), NO
2
(12%) and nickel (6%), the rest of
pollutants representing less than 9%. As concerns the natural gas chain, HTP
represents approximately 12,800 t 1,4 DCB eq., mainly due to the lead emissions
in soil generated during the treatment stage (94%). The oil chain presents a value
of 15,639 t 1,4 DCB eq. for the same indicator mainly due to the Pb emission
(63%).
Table 8
Impact indicators for the oil chain
Impact indicators
Stages
Extraction Treatment Transport Combustion Total
ADP [t Sb eq.]
4,848 0 0 0 4,848
GWP [t CO
2
eq.]
32,459 28,938 137 865,937 927,471
AP [t SO
2
eq.]
306 129 12 2,186 2,633
POCP [t ethene eq. ]
16.5 7.6 0.5 75 99.6
EP [t PO
4
3-
eq.]
13 8.5 0.3 195 216.8
HTP [t 1,4 DCB eq.]
302 14,128 7 1,202 15,639
FAETP [t 1,4 DCB eq.]
0,4 25 0 154 179.4
MAETP [t 1,4 DCB eq.]
588 46,028 17 32 46,665
TETP [t 1,4 DCB eq.]
1.7 129 0 17 147.7
Life cycle impact assessment of fossil fuels 125
Relating to the „acidification” indicator, the values obtained in this study are
10,200 t SO
2
eq. corresponding to the coal chain (the contribution of the SO
2
amounting to 80%) 640 t SO
2
eq. for the natural gas chain (the contribution of
the SO
2
emission amounting to 51% and of the NO
x
to 43%) and 2,633 t SO
2
eq. for the oil chain, the pollutants causing this impact category being SO
2
which contributes approximately 76% and NO
x
having a 24% share within the
total calculated value for this indicator.
From the point of view of the „eutrophication” indicator, the life cycle of coal
registers a value of 476 t phosphate eq., while natural gas presents a value of
90 t phosphate eq.. For the oil chain the registered value is 216,8 t phosphate
eq., by far lower than in the other two cases. The main pollutant contributing
to this impact class is NO
2
(NO
x
), regardless of the utilized type of fuel; in the
case of the coal chain its contribution rises to 92% mainly generated during
the combustion stage; the nitrogen oxide contribution in the case of the natural
gas chain is 81
_% while the in the case of the oil chain it reaches
approximately (including all the nitrogen compounds) 100
_%.
As concerns the „photochemical pollution” indicator, the values obtained in
this study are 428 t ethene eq. for the coal chain (the SO
2
emission contributes
75%), 48 t ethene eq. for the natural gas chain (the CH
4
emission contributes
47%, SO
2
contributes 27% and CO contributes 16%) and 99,6 t ethene
equivalent for the oil chain, the SO
2
emission contributing approximately 64%
of the total value of this indicator.
The „freshwater aquatic toxicity” indicator has the following values: for the
coal chain 680 t 1,4 DCB eq. of which beryllium contributes 44%, selenium
23%, vanadium 15%; in the case of the natural gas chain 93 t 1,4 DCB eq. of
which CH
2
O mainly contributes 77%, while for oil 179,4 t 1,4 DCB eq.
covered 100% by Pb.
The „marine aquatic toxicity” indicator has the following values: for the coal
chain 10,021 t 1,4 DCB eq. of which the main pollutants are vanadium
contributing 32%, selenium 30%, mercury 10% and nickel 9,5%; in the case
of the natural gas chain, the value is 39,363 t 1,4 DCB eq., of which lead
contributes 100%, and in the case of the oil chain the value of this indicator is
46,665 t 1,4 DCB eq. of which Pb contribution is 100%.
The „terrestrial eco-toxicity” indicator registers the following values: for the
coal chain 219 t 1,4 DCB eq. with the following pollutant contributions:
mercury 54%, vanadium 15%, beryllium 11% and selenium 7%; for the
natural gas the value of the indicator is 119 t 1,4 DCB eq. within which lead
contributes 93%, and for the oil chain the indicator value is 147.7 t 1,4 DCB
eq.).
126 Cristian Dincă, Adrian Badea, Tiberiu Apostol
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CCS, Environmental Engineering and Management Journal, January/February 2009, vol. 8,
no. 1, pp. 81-90, ISSN: 1582-9596.
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Valeur environnementale de l'energie
  • T P Rousseaux
. P. Rousseaux, T.Apostol, Valeur environnementale de l'energie, Presses polytechnique et universitaires romandes et INSA de Lyon, 2000
GHG emissions evaluation from fossil fuel with CCS, Environmental Engineering and Management Journal
  • A C Dinca
  • T Badea
  • G Apostol
  • Lazaroiu
. C. Dinca, A. Badea, T. Apostol, G. Lazaroiu, GHG emissions evaluation from fossil fuel with CCS, Environmental Engineering and Management Journal, January/February 2009, vol. 8, no. 1, pp. 81-90, ISSN: 1582-9596.
Valeur environnementale de l'energie, Presses polytechnique et universitaires romandes et INSA de Lyon
  • P Rousseaux
P. Rousseaux, T.Apostol, Valeur environnementale de l'energie, Presses polytechnique et universitaires romandes et INSA de Lyon, 2000