Dottorato di Ricerca in Ingegneria Civile e Industriale. Ciclo XXIX SSDThe thermal power plant for the generation of electricity, which uses coal as a primary
energy source, presents multiple issues linked to the emission of pollutants and
greenhouse gas (CO2) into the atmosphere. Furthermore, the conventional boilers
greatly contribute to the increase of these harmful substances. The aim of this work is
to propose and analyze the possibility of combining two new combustion technologies:
the so-called oxy and MILD combustion. The rst one, allows to capture the carbon
dioxide, while the second one provides several advantages, not only because it reduces
the emission of nitrogen oxides, but also because it is characterized by uniform
ows in
the combustion chamber. Therefore, the challenge is to combine the two technologies
with applications in furnaces and a new concept of boiler. For the latter, the planned
applications include the ultra-super critical plants. For this reason, numerical
simulations have been carried out by means of technical CFD (Computational Fluid
Dynamics) because it is hard to provide large-scale tests. The initial phase of the work
involves the application of the two technologies in furnaces. The rst one focuses on
the MILD combustion by analyzing di erent positions of the pulverized coal jet, while
the second one focuses on the application of the combination of the two technologies in
order to analyze their e ects in terms of temperature and species concentration
distributions. The next phase of the work, instead, has a focus on an innovative boiler.
The testing of di erent geometrical solutions and models of char combustion has also
allowed to study their e ects in terms of temperature, combustion products
concentrations, burnout and, above all, wall heat
ux. These latter results have been
compared with the ones of traditional boilers and the results reported in the literature.
The nal aim of this work is to analyze the advantages deriving from the combination
of two technologies into a new concept of boiler, in order to reduce pollutant emissions,
greenhouse gases and obtain a better performance than the one at the current state of
the art.Università della Calabri