Pm. Lemieux et al., WASTE AND SORBENT PARAMETERS AFFECTING MECHANISMS OF TRANSIENT EMISSIONS FROM ROTARY KILN INCINERATION, Combustion science and technology, 116(1-6), 1996, pp. 499-515
When ''containerized'' liquid wastes, bound on sorbents, are introduce
d into a rotary kiln in batch mode, transient phenomena involving heat
transfer into, and waste mass transfer out of, the sorbent can promot
e the rapid release of waste vapor into the kiln. This rapid vapor rel
ease can cause depletion of available oxygen, and the formation of a '
'puff'' which can result in a temporary failure of the incinerator sys
tem. A systematic study has been completed examining the effect of was
te and sorbent properties on the magnitudes of transient puffs in a la
boratory scale rotary kiln simulator. Of primary importance were waste
boiling point and waste stoichiometric oxygen requirement. Of seconda
ry importance were sorbent parameters such as bulk void fraction, and
the fraction of the adsorbed waste that was contained within the indiv
idual sorbent particles. A theoretical model that utilizes a vaporizat
ion/surface renewal approach can be used as a guide to explain experim
ental results for several wastes on sawdust and corncob sorbents. Resi
n sorbents, on the other hand, are extremely effective at controlling
puffs because they appear to be able to bind the liquid waste tightly
to the sorbent in such a way that it is not released by a vaporization
process. This non-physical waste release process is not described by
the current model. In general, the results suggest that the practice o
f limiting containerized waste feed rates based on the heat of combust
ion of a given container be modified to provide feed rate limitations
based on the stoichiometric oxygen requirements and boiling point of w
aste in a given container. This modified practice may enable container
ized waste feed rates to be optimized, with a view to minimizing both
the transient load on the afterburner and the transient emissions from
the stack.