HCI Sorption by Dry NaHCO₃ for Incinerator Emissions Control

Reaction kinetics of hydrogen chloride with sodium carbonate

“…These results confirm and extend the results obtained by Fellows and Pilat (1990), who showed that changes in the HCl concentration in the range of 428-760 ppm appear to have little effect on the collection efficiency, and the conclusions from Duo et al (1996).…”

“…This circumstance allows to deduce that the effect of the space velocity can be assumed negligible in the range of the investigated parameters. The same conclusions were drawn by Fellows and Pilat (1990), who reported that the sorption reaction was only weakly dependent on the superficial gas velocity in the range 0.06 and 0.11 m s −1 .…”

“…This effect is particularly evident at the lower temperature values, where the conversion of the carbonate layers is about 10% higher than those obtained with a particle size of 209 m. On the contrary, in the high temperature region the differences become almost insignificant. It is possible to argue that the influence of the sorbent particle size in the investigated range can be considered negligible, as already reported in the literature (Fellows and Pilat, 1990;Duo et al, 1996).…”

“…Dvirka et al (1988) from theoretical calculations predicted that the reduction of hydrogen chloride concentrations from 208 to 5 ppm at 315 • C by contact with sodium carbonate requires less than 0.001 s. Laboratory measurements of HCl collection efficiency conducted by Fellows and Pilat (1990) in a fixed bed of NaHCO 3 showed that HCl sorption increased strongly increasing temperature from 107 to 288 • C, but was only weakly dependent on particle diameter. Duo et al (1996) studying the behaviour of sodium-based sorbents in the temperature range 300-600 • C found that both the influence of gas composition and particle size may be neglected, while the effect of the temperature is strong.…”

The Effect of Structure Modification of Sodium Compounds on the SO2 and HCl Removal Efficiency from Fumes in the Conditions of Circulating Fluidised Bed

“…Sodium bicarbonate also shows high reactivity against hydrogen chloride 4,5,[11][12][13] . Depending on the temperature, gas hydrogen chloride reacts with sodium bicarbonate in a direct (5) or indirect way after decomposition into sodium carbonate (2) according to the reaction (6): NaHCO 3 +HCl → NaCl + H 2 O + CO 2 (5) 2HCl + Na 2 CO 3 → 2NaCl + CO 2 + H 2 O (6)…”