Ministry of Agriculture, Livestock and Food Supply - Embrapa

the charcoal for the steel industry in 1997 and 28% of all charcoal in 2002.
Technology began to evolve from the traditional kilns to rectangular furnaces,
and more efficient processes are gradually being adopted. The use of planted
forests also reduces transportation costs.
The interest of steel mills in charcoal was renewed due to the prospects
of using the CDM to reward "green steel". Cleaner and more efficient
technologies are being sought, including the use of byproducts (from tar to
effluent gases). It is estimated that the current pig iron production (27-million
tons) would require 17.5-million tons of charcoal, with a planted area of
approximately 3.3-million hectares.
Agricultural and forestry residues
The development of technologies to treat and use residues with a view
to reducing production costs and environmental pollution is the greatest
challenges of our time.
This challenge is very important in regions that concentrate animal
production activities, particularly swine and poultry farms. On the one hand,
producers are under pressure to increase productivity and the number of
animals in small production areas. On the other, there are increasing pressures
to ensure that said increase does not destroy the environment. Limited space
and the need to meet increasing demands for energy, good quality water and
food have presented some challenges to producers, most of which are related
to the environmental issue and the availability of energy (OLIVEIRA, 2003;
SANTOS, 2001).
The energy potential of residues is hard to estimate because of statistical
unreliability and regional variations. Nevertheless, Woods and Hall (1994) point
to values close to 93 EJ/year. That number is similar to Smil's (1999), who
concluded that there are from 3.5 to 4-billion tons of agricultural residues,
with an energy potential of 65 EJ, or 1.5 Gtep. Considering only the main
crops (wheat, rice, corn, barley, and sugarcane), Hall et al. (1993) estimated
that it is possible to recover 25% of the residues in the form of energy, generating
38 EJ and thus avoiding the emission of 350-460 Mt of CO per year.
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The use of residues for energy purposes will compete in the future with
the preparation of animal bedding for livestock farms, organic fertilizers, erosion
control, animal nutrition, etc. It would also be necessary to reinforce the concept
of residue from the viewpoint of the sustainability of its exploitation, i.e., not
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