An Absorption-Adsorption Apparatus for Gases Purification from SO2 in Power Plants

Abstract

Different companies propose methods and apparatuses for waste gases purification from SО 2 using two-phase absorbent (CaCO 3 suspension).The basic problem of the carbonate absorbents is that its chemical reaction with SO 2 leads to CO 2 emission, which leads to similar ecological problems. The use of synthetic anionites as adsorbents for gas purification from SO 2 provides possibilities for adsorbent regeneration. In a proposed method, the waste gas purification is realized in two steps-physical absorption of SO 2 with water in a counter-current column and chemical adsorption of HSO− from the water solution by synthetic anionite particles. The adsorbent regeneration is made with NH 4 OH solution. The obtained (NH 4 ) 2 SO 3 (NH 4 HSO 3 ) is used (after reaction with HNO 3 ) for production of concentrated SO 2 (gas) and NH 4 NO 3 (solution). The proposed method permits to be used the absorption columns, where are used the CaCO 3 suspensions. In this paper, the efficiency of the waste gases purification from SО 2 is increased in an absorption-adsorption apparatus, where the absorption is realized in co-current flows and the adsorption takes place in the flexible adsorbent. For this is proposed a new absorption-adsorption column apparatus with bubbling plates. A mathematical model of the absorption-adsorption process is presented, too.

Integrated Absorption–Adsorption Process for Waste-Free Decontamination of Gases from Sulfur Dioxide, Part 2: CFD Modeling and Experimental Investigation of a Bubble-Cap Tray

“…The present study is directed towards development of a practically waste-free FGD technology in a tray column, Figure 1. The proposed absorption-adsorption method [27,28] includes absorption of SO 2 in water with simultaneous adsorption of the resulting H 2 SO 3 from the water with a synthetic anion-exchange resin. The adsorbent is regenerated with a solution of NH 3 , followed by decomposition of the obtained (NH 4 ) 2 SO 3 with HNO 3 .…”

“…The conceptual diagram in Figure 1 is the starting point for designing the experimental set-up for the present study. The integrated absorption-adsorption process (Figure 1) [27] for SO2 removal from flue gases is carried out in a tray column (1), provided with an inlet pipe (2) at the bottom The integrated absorption-adsorption process (Figure 1) [27] for SO 2 removal from flue gases is carried out in a tray column (1), provided with an inlet pipe (2) at the bottom for the supply of flue gas and an outlet pipe (3) at the top for the removal of the purified gas. The column is connected to a sorbent regeneration system (9).…”