Page 24 - Academic Press Encyclopedia of Physical Science and Technology 3rd BioTechnology

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Encyclopedia of Physical Science and Technology EN002G-61 May 19, 2001 19:33

Biomass, Bioengineering of 149

FIGURE 4 Human needs for protein and calories vs. nutrient production in crops and lignocellulosics.

is also some consumption of plant matter for industrial forages, about two thirds of which was grazed as pasture
uses, the subject of this article.) and the rest of which came from harvested forages such as
Past history suggests that people seek to increase their hay and silage. The remainder of animal feed consumed
consumption of meat, milk and eggs as their income was concentrates such as corn, sorghum, oats, wheat, etc.
grows. Looking at these consumption figures in a differ- If it were possible to derive more and better animal feeds
ent light, if we found another way to meet more of the from forages and other lignocellulosic materials, it might
protein and energy (calorie) needs of our animals from be possible to increase the use of agricultural raw mate-
sources other than grains and oilseeds, we could then free rials for biobased industrial products without negatively
up large quantities of grain and oilseed crops for other impacting food availability and food prices.
uses, including industrial uses. From the crop production
statistics quoted above it is obvious that the potential and
actual production of grasses and other lignocellulosic ma-
3. Existing Fuels/Chemicals/Materials
terials far exceeds the production of grains, oilseeds and
Uses of Biomass
sugar crops.
As described above, biomass has long been used as a solid
fuel, as a building material and also as a source of fiber
for clothing and paper. These uses continue. In the United
2. Animal Feeds
States,theforestproductsindustryisvaluedat$200billion
In 1998 the United States produced about 40 million tons per year and the cotton produced is worth another $5 bil-
of beef, pork, and poultry as well as billions of dozens lion per year. Prior to the early 1800s, biomass was in fact
of eggs and tens of millions of tons of milk. To gener- the chief source of fuel and materials. With the coming of
ate these products, livestock and poultry consumed well the Industrial Revolution, a gradual switch from biomass
over 500 million tons of feed expressed on a feeding value as the major fuel source took place, first through a transi-
equivalent to corn. Over half of this total feed was from tion to coal and later to petroleum and natural gas. The oil