Environmental Engineering Reference
In-Depth Information
taBle 18.3
Fa composition (wt %) of major vegetable oils
oil crop
12:0
14:0
16:0
18:0
18:1
18:2
18:3
22:1
Rapeseed
-
1.5
1-4.7
1-3.5
13-38
9.5-22
1-10
40-64
Soybean
-
-
2.3-11
2.4-6
22-31
49-53
2-10.5
-
Sunflower
-
-
3.5-6.5
1.3-5.6
14-43
44-68.7
-
-
Oil Palm
-
0.6-2.4
32-46.3
4-6.3
37-53
6-11
-
-
Cotton
-
0.8-1.5
22-24
2.6-5
19
50-52.5
-
-
peanut
-
0.5
6-12.5
2.5-6
37-61
13-41
-
1
Safflower
-
-
6.4-7
2.4-29
9.7-13.8
75.3-80.5
-
-
Source:
Derived from Canakci, M. and Sanli, H.,
J Indust Microbiol Biotechnol Special Issue
,
pp 1-23, 2008; Han, J.,
Advances in Plant Lipid Research
. Secretariado de Publicaciones de
la Universidad de Sevilla, Sevilla, Spain, pp 665-668, 1998.
considerably in September 2008 and RME prices (1,415 U.S.$/t) came close to diesel fuel prices
(Pinzi et al. 2009).
The cost of biodiesel is determined by taking the difference between the total cost to produce
RME and the total income from the byproducts (Walker 2004) where total cost refers to capital
costs, operating costs, labor, power, annual maintenance, capital interests, purchase of feedstock,
miscellaneous costs relating to administration/management, and total income including those from
the sales of the meal and the glycerol byproduct. However, studies (Zhang et al. 2003; Haas et al.
2005) have shown that a major portion (<85%) of the cost for biodiesel production is attributed to
the cost of feedstock. Walker 2004 estimated that the per liter cost of RME in a 22-million-L facility
under U.K. conditions was approximately £0.31 or approximately 0.50 U.S. $. It was concluded
that the production of biodiesel was not economical when compared to the cost of mineral diesel
production (~£0.10 or 0.16 U.S.$/L) at that time.
The EU and Canada are the main regions where food-grade canola is used as feedstock for
biodiesel production, however, to produce economically competitive biodiesel in these regions it
has been necessary to take measures such as application of tax credits, optimization of processes
to maximize the RME yield and use of alternate lower cost feed stock such as nonedible
Brassica
(
B. carinata
) oil. According to The Canola council of Canada (http://www.canola-council.org), in
spite of the economic noncompetitiveness of biodiesel with petrodiesel fuel, a canola-based-biodiesel
industry would benefit Canadians by creating more than 700 direct jobs in crushing, processing and
food production industries. An investment in biodiesel infrastructure will also enhance economic
activity in construction and supporting industries. Additional market development for the byproducts
would help the economics.
If the oil supply dwindles or regulations insist on the use of biodiesel, it will no longer matter if
biodiesel is competitively priced or not. The required infrastructure will already be available if steps
are taken now. Some industries may also voluntarily choose to use biodiesel in spite of the economics
because of public opinion, concerns about emissions, company green policies or desire to use local
resources. Additional market development for the byproducts would help the economics of biodiesel.
18.4 Food-versus-Fuel consIderatIons
A major concern associated with the production of biodiesel is its reliance on vegetable or canola
oil. There is a perceived competition between food and fuel uses of the edible oils, posing a putative
moral dilemma. The issue is being debated in scientific journals as well as in popular press but there
are very few actual scientific studies that help to dissect out the socioeconomic implications of using
food crops for both food and fuel.
