Líneas de
Investigación
RESEARCH AND DEVELOPMENT OF TECHNOLOGIES FOR ACID GASES REMOVAL
The research objectives are
mainly two, and special attention is paid to desulfurization
processes at low and medium temperatures due to their complex
behaviour and technical interest:
a) Analysis and modelling
of gas/solid non-catalytic reactions and their optimization
in technical processes of acid gas treatment.
b) Obtention,
characterization and application of calcitic sorbents to the
desulfurization reaction.
Specific objectives of the
research topic are:
1. Kinetics of non-catalytic
gas/solid reactions and optimization of technologies for the
removal of acid pollutants in flue gas streams.
The objective is the modelling of
the flue gas desulfurization processes based on the injection of
a solid sobent in the post-combustion zones of power coal plants
(economizer, and duct section previous to the particulate
collection device).
The in-duct desulfurization
technology at low temperatures involves the injection of a dry
calcitic sorbent in the flue gas humidified by water spraying in
the ductwork downstream of the air preheater but ahead of the
particulate collector. The total SO2 removal is the sum of
captures in the duct section and in the particulate control
device. Since the residence time in the duct is very short (up to
3 seconds), sorbents with high reactivity are required for
significant desulfurization yields.
The kinetic modelling has been
performed considering the non ideal adsorption of SO2 on the
solid as the rate – controlling step.
The experimental
systems used for the desulfurization studies include two complete
set-ups at different scales which are resumed in figures 1 and 2:
a fixed reaction system at laboratory scale and a duct injection
reaction system at mini pilot scale, respectively.
Figure 1
Figure 2
2. Obtention, characterization and application of calcitic
sorbents for technologies of acid pollutants removal in flue gas
streams.
New silica-enhanced lime sorbents
are also developed on the basis of the reuse of fly ash as a
reagent material for dry FGD systems, both economically and
environmentally attractive because its ability for increasing the
sorbent utilization as a consequence of the pozzolanic reaction
between fly ash and Ca(OH)2 in the presence of water to form
highly hydrated and reactive CaO.SiO2.Al2O3.H2O systems. The
optimal conditions of obtention and the kinetic study of the
process of preparation of these new sorbents is also
investigated.
More information can be obtained
from the research proyects, and the main results are
described in the publications .
The technical facilities of
the research group are:
- A fixed bed reactor system at
laboratory scale for experiments at medium and low
temperatures (up to 1 l/min of gas flowrate). Own design.
- A duct-injection system at
mini pilot plant scale (up to 60 l/min of gas flow). Own
design.
- BET Specific Surface
equipment, Micromeritics ASAP 2000.
- Hg Porosimeter, Micromeritics
Pore Sizer 9310.
- Laser Diffraction equipment,
Malvern Mastersizer X.
- Thermogravimetric Analyzer,
Perkin Elmer TGA 7
- NDIR continuous analyzer of
SO2 , Rosemount NGA 2000.
- UV continuous analyzer of NO,
Rosemount NGA 2000, with a previous NOx converter to NO.
| 
