Page 134 - Materials Chemistry, Second Edition

120 K. T. Lee and C. Ofori-Boateng
Table 3 Characterization of air and water emissions in PME production
Type of emission LCIA category
a
Emissions to air GWP (CO 2 eq./g) 2 100 years
Carbon dioxide (CO 2 ) 1
Nitrous oxide (N 2 O) 310
Carbon monoxide (CO) 3
Methane (CH 4 ) 21
Carbon tetra-fluoride (CF 4 ) 6,300
Sulfur hexafluoride (SF 6 ) 23,900
Hydro fluorocarbon (HFC) 140–12,100
Per-fluorocarbons (PFC) 6,500–9,200
AP (SO 2 eq./g) b
Sulfur dioxide (SO 2 ) 1
Oxides of nitrogen (NO x ) 0.7
Hydrochloride acid (HCl) 0.88
Hydrogen fluoride (HF) 1.6
Nitrogen monoxide (NO) 1.07
Nitrogen dioxide (NO 2 ) 0.7
Ammonia (NH 3 ) 1.8
Emissions to water EP (PO 4 eq./g) c
3-
Phosphates (PO 4 ) 1
Nitrates (NO 3 ) 0.42
Nitrogen oxides (NO x ) 0.13
Ammonia (NH 3 ) 0.33
a
U.S. DOE/EIA (1997)
b
Heijungs (1992)
c
Mark et al. (2001)
summed up to obtain a single number for the total environmental impact. Table 3
shows a summary of LCIA classification and characterization estimations asso-
ciated with PME production.

4.3.3 Valuation

This step uses results from the LCIA to evaluate each process for improvements in
the performance of every stage associated with the life cycle of palm oil biodiesel.

5 LCA Results and Interpretation

The major objective of this chapter’s LCA interpretation is to detect or assess the
points of potential environmental impacts which can lead to overall improvement
of the performance of the palm oil biodiesel production industries in the world,
especially in Malaysia. Figure 13 summarizes the environmental impact associated
with each life cycle stage of PME production. Figure 14 shows the environmental