Page 129 - Materials Chemistry, Second Edition

Life Cycle Assessment of Biodiesel from Palm Oil 115

Table 2 (continued)
Unit Quantity Energy coefficient Total energy
(MJ/kg) (MJ)
SO 2 kg -0.00454 29.50 -0.1339
Hydrocarbons (HC) kg -0.00454 –
CO kg -0.05543 10.11 -0.5604
All quantities are wet weight averages from (MPOB 2010; Felda 2010; Schmidt 2007; Subr-
amaniam et al. 2008; Yusoff 2006; Wicke et al. 2008)
Net energy value (NEV) = energy content of PME - net energy inputs = 20.28 MJ
NRnEV = energy content of PME - fossil energy inputs = 24.63 MJ
Net energy ratio (NER) = net energy outputs/net energy inputs = 1.4893

rock phosphate), 17 kg of potassium oxide, and 2 kg of magnesium oxide or
kieserite (Von Uexkull and fairhurst 1991; Hartley 1988). At the early stage after
transplanting, urea and limestone may be applied to the young palms at a rate of
6–8 kg/palm tree (Von Uexkull and fairhurst 1991). Borate is currently applied to
oil palms up to the age of 6 years. Paraquat and glyphosate as herbicides are also
applied twice or thrice a year at a rate of 0.625–1.25 kg/ha/time and
1.875–3.125 kg/ha/time, respectively (Von Uexkull and fairhurst 1991). Water
requirement for the oil palm cultivation is assumed to be from rain water and
irrigation at early stages of transplanting. The CHP system of the mill is assumed
to utilize the PPF and palm kernel shells as fuel to produce heat for steam and
electricity generation.

4.2.3 Transportation

The nursery field is assumed to be about 1.7 km away from the oil palm plantation
field. The oil mill is assumed to be situated closer to the oil palm plantation; hence,
the distance is negligible. CPO transportation to CPO refinery is assumed to be
part of the biodiesel production plant which is estimated to be 296 km away from
the oil mill.

4.2.4 Energy Analysis

For the production of 1 kg PME with energy content of 39.84 MJ, the NEV and
NER of the whole life cycle of PME production are 20.28 MJ per kg of PME and
1.489 (without energy production from EFB, PPF, etc.), respectively. The NER
would have been 4.81 if all EFB, PPF, PKS, etc., were considered as energy source
(which is considered in this chapter). This clearly shows an energy profit for the
PME production system. The total life cycle energy consumption of the PME
product system is shown to be 20.28 MJ per kg PME.