For a long time in world steelmaking, charcoal was used
exclusively as a fuel and reducing agent. Brazil is one of the few
countries in the world that offers major potential for biomass
production and use. It is the world's leading producer of charcoal
with annual production estimated at 9 million tons [1]. Around 75% of
that production goes to the steelmaking sector [2]. Unfortunately,
most of the kilns used to carbonize wood are not mechanized and
the technologies used still remain outdated [3]. In order to guarantee
sustainable development of the steelmaking sector, companies need
to be modernized developing and adopting new, more efficient
carbonization technologies [4].
Of the promising technologies like continuous hot rinsing gas
retort (Lambiotte, Reichert) or discontinuous batch retort (DPC, CML),
we have chosen pressurized carbonization. This process has been
studied for several years by the University of Hawaii and CIRAD [5].
The aim of this paper was to determine in a statistically valid manner
how pressure impacts on charcoal quality. The goal for this study was
to investigate causality and, in particular, to draw conclusions on how
changes in the value of independent variables (pressure, temperature