Environmental Engineering Reference
In-Depth Information
(a)
(b)
(c)
FIGure 24.1 (see color insert)
Identification and tapping of
C. langsdorfii.
trees near Nova Odessa, Sao
Paulo State, Brazil. (a) A
C. langsdorfii.
tree growing near a farm in Nova Odessa, Brazil. The trees grow as
single individuals rather than in stands, making it difficult to locate and tap multiple trees. (b) Tapping a
C.
langsdorfii.
tree with a manual drill. The oils collect in the heartwood and so the hole must be drilled to the
very center of the tree, making collection difficult. (c) Botanical characterization of
C. langsdorfii.
. Pictures of
leaves, seeds with fleshy aril, and seed pods were taken to correctly identify the genus and species of the trees.
The important properties of diesel fuel are the cetane rating, low-temperature operability, and
volumetric heating value. Diesel engines produce combustion by compressing air, which, in turn,
heats the air; at a designated moment of compression, fuel is injected into the chamber as tiny
droplets which vaporize and ignite. The cetane rating measures the ignition quality of fuels, or how
readily the fuel burns. A fuel's quality of ignition can have implications in starting engines in cold
conditions, as well as emissions, smoothness of operation, noise, and misfires (Bacha et al.
2007).
Low temperatures can cause some constituents in diesel fuels to solidify (such as the paraffins).
This, in turn, can clog the fuel filter and stop the flow of fuel to the engine. This effect is measured
with “cloud points,” the temperature at which the waxes in the mixture begin to solidify, or the
“pour point,” the temperature when the fuel becomes so thick that it will no longer pour. The
volumetric heating value measures how much energy the fuel has per volume. Volumetric heating
values influence torque, horsepower, and to some degree, fuel economy.
