The Influence of SO₂ and HCl Concentrations on the Consumption of Sodium Bicarbonate during Flue Gas Treatment

Abstract

The paper focuses on the competitive influence of SO 2 and HCl during their removal from flue gas by sodium bicarbonate. The experimental investigation was conducted at a unique combination of conditions: the experiments were conducted on a large scale, with real flue gas, and the removal of SO 2 and HCl was studied simultaneously. The aim was to ensure that experimental conditions are reasonably realistic and therefore transferable to practice. The results from experiments at various temperatures within the range from 170 to 255 °C did not indicate a significant influence of temperature. The sorbent conversion varied significantly with the lowest achieved conversion of 26% and the highest conversion of 85%. There was a clear trend showing that higher concentrations of HCl make it more difficult to achieve the selected target concentration of SO 2 in clean flue gas, suggesting the preferred reaction of formed sodium carbonate with HCl. The influence of HCl on the removal of SO 2 was quantified and is presented in the form of regression models. The found regressors were the initial concentrations of HCl and SO 2 in raw flue gas and the target concentration of SO 2 in the clean flue gas. The regression models are in good agreement with the experimental data and can be used for the prediction of the behavior of a flue gas treatment system or its optimization.

Novel application of sodium manganese oxide in removing acidic gases in ambient conditions

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In this study, we have exploited the basic sites in Na x MnO 2 for room-temperature oxidation of H 2 S, SO 2 , and NO 2 gases in ambient conditions. The fabricated material was tested in column breakthrough configuration with 100-500 ppm of acidic gases to confirm its applicability in real-world problems involving flue gas purification 17,18 . The material exhibited a better gas chemisorption efficiency in wet conditions.

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Numerical Simulation on the Sodium-Based Dry Desulfurization Process in Low SO2 Concentration Flue Gas

“…Kong et al 25 showed the possibility to use sodium bicarbonate to remove HCl and SO 2 effectively and summarized a guideline for the design of the removal system. Zach et al 26 investigated the competitive influence of SO 2 and HCl in their removal by sodium bicarbonate and found that a higher concentration of HCl reduced the removal efficiency of SO 2 . Dal Pozzo et al 27 concluded that the thermal activation of sodium bicarbonate played a key role in the reactivity toward HCl and SO 2 .…”

Chemisorption of SO2 and NO2 gas over Na0.4MnO2 in ambient conditions: an experimental and theoretical study

“…To test its practical applicability, the material was examined in a column configuration with 100 ppm of acidic gas diluted in ambient air, which is representative of flue gas purification problems experienced in real-world settings. 10,11…”