Environmental Engineering Reference
In-Depth Information
DID YOU KNOW?
In the 1980s, the USDOE gradually shifted its focus to technologies that could
have large-scale impacts on national consumption of fossil energy. Much of
the USDOE's publications from this period reflect a philosophy of energy
research that might, somewhat pejoratively, be called “the quads mentality.”
A quad is a short-hand name for the unit of energy often used by the USDOE
to describe the amounts of energy that a given technology might be able to
displace. Quad is short for “quadrillion Btus”—a unit of energy representing
10
15
(1,000,000,000,000,000) Btus of energy. This perspective led the USDOE
to focus on the concept of immense algae farms.
Before discussing the algae-to-biofuels process in detail, it is important for the
reader to be well grounded in basic algal concepts. In many ways, the study of micro-
algae is a relatively limited field of study. Algae are not nearly as well understood
as other organisms that have found a role in today's biotechnology industry. The
study of microalgae represents an area of high risk and high gains; it also presents
an opportunity for the curious and ambitious to break new ground in science by con-
ducting research in this growing area of interest.
Algae can be both a nuisance and an ally; we might say they possess Jekyll and
Hyde-like (good vs. bad) characteristics. Many ponds, lakes, rivers, streams, and
bays (e.g., Chesapeake Bay) in the United States and elsewhere are undergoing
eutro-
phication
, which is basically the killing off (although in many cases very slowly) of
calm water environments, especially ponds, marshes, and lakes, due to enrichment
of an environment with inorganic substances (phosphorous and nitrogen). When
eutrophication occurs, when filamentous algae such as
Caldophora
break loose in a
pond, lake, stream, or river and wash ashore, algae makes it stinking, noxious pres-
ence known. More important than the offensive odor that dying algae give off is the
fact that their deaths begin a biodegradation process whereby instead of adding oxy-
gen to their watery environment they begin to use it up. Algae have a good side, too.
For example, algae are allies in many wastewater treatment operations. In addition,
they can be valuable in long-term oxidation ponds where they aid in the purification
process by producing oxygen. Before discussing the specifics and different types of
algae, it is important to be familiar with terminology associated with algae.
•
Algae
—Large and diverse assemblages of eukaryotic organisms that lack
roots, stems, and leaves but have chlorophyll and other pigments for carry-
ing out oxygen-producing photosynthesis.
•
Algology
or
phycology
—The study of algae.
•
Antheridium
—Special male reproductive structures where sperm are
produced.
•
Aplanospore
—Nonmotile spores produced by sporangia.
•
Benthic
—Algae attached and living on the bottom of a body of water.
•
Binary ission
—Nuclear division followed by division of the cytoplasm.
•
Chloroplasts
—Packets that contain chlorophyll
a
and other pigments.
