ef7b03292_si_001.pdf (1.56 MB)
Hydrogen Chloride Removal from Flue Gas by Low-Temperature Reaction with Calcium Hydroxide
journal contribution
posted on 2017-12-07, 00:00 authored by Alessandro Dal Pozzo, Raffaela Moricone, Giacomo Antonioni, Alessandro Tugnoli, Valerio CozzaniMunicipal
solid waste incineration (MSWI) is a method of waste
valorization whose overall sustainability depends on the effective
removal of the gaseous contaminants generated. Hydrogen chloride (HCl)
is a typical pollutant formed in waste combustion. Dry processes based
on its reaction with basic powders such as calcium hydroxide are among
the state-of-the-art best available technologies for MSWI flue gas
treatment. An experimental investigation of the heterogeneous reaction
process between hydrogen chloride and calcium hydroxide in the temperature
range between 120 and 180 °C was carried out. A laboratory-scale
fixed bed reactor connected to a Fourier transfrom infrared (FTIR)
spectrometer was used for the online continuous monitoring of HCl
conversion. Solid reaction products were characterized using thermogravimetric
analysis and X-ray diffractometry. The experimental data collected
were used to validate a fundamental kinetic model for the description
of the gas–solid reaction between Ca(OH)2 and HCl.
A sensitivity analysis was carried out to assess the importance of
the different temperature-dependent parameters in the model. The results
allow an improved understanding of the heterogeneous reaction process
that is applied in acid gas dry removal processes.