Cellular concrete waste: An efficient new way for H2S removal

Hybrid Filtration Process for Gas Desulfurization

“…CC is mainly composed of SiO 2 (50.5% in weight), CaO (24.6%), SO 3 (19.7%), Al 2 O 3 (2.2%), P 2 O 5 (1.4%) and Fe 2 O 3 (1.3%). It was evidenced that in the presence of H 2 S, and under wetted conditions, complex physico-chemical mechanisms occur between H 2 S and the CC components, simultaneously leading to the H 2 S removal and a modification in the composition of the material [22,23]. The ability of the CC to remove H 2 S as well as its lifetime were predicted from experimental results [22].…”

“…Before its use as a packing mater was sieved to use only pieces around 10 mm in diameter. CC is mainly composed (50.5% in weight), CaO (24.6%), SO3 (19.7%), Al2O3 (2.2%), P2O5 (1.4%) and Fe2O3 (1 was evidenced that in the presence of H2S, and under wetted conditions, complex p chemical mechanisms occur between H2S and the CC components, simultaneously to the H2S removal and a modification in the composition of the material [22,23]. The of the CC to remove H2S as well as its lifetime were predicted from experimental resu Expanded schist (Granulex company, Mayenne, France, www.granulex.fr), a lig dish-brown material with a smooth surface, is a type of rock with a characteristic l foliated structure.…”

“…However, to date, there are only few sources of data on the ability of the cellular concrete to remove H 2 S, and further investigations are still needed to improve knowledge on this process. The first findings on this topic [22,23] showed that reactions occurring between H 2 S, O 2 and the components of the cellular concrete (mainly calcium oxides and ferric oxide) modify the structure of the material, leading to gypsum formation (CaSO 4 2H 2 O), which, consequently, limits its lifetime. The presence of large amounts of sulfate in water (Figure 6) confirmed the reaction mechanisms leading to gypsum formation due to reactions of calcium carbonate or calcium hydroxide with sulfuric acid (note that the decrease in the sulfate concentration observed after day 64 is due to water replacement to keep pH > 1).…”

“…But further studies are needed to confirm the feasibility of this solution in terms of the empty bed residence time of the gas (EBRT), the variation of H 2 S concentrations, pressure drops (∆P) and resilience. Moreover, it was recently demonstrated that H 2 S can be efficiently removed by a simple filter filled with cellular concrete (CC) waste [22]. As the H 2 S concentration in some biogases can be very high (several thousands of ppm), which can be detrimental to a biological system, a pre-treatment step may be necessary to limit the concentration to be treated.…”

Investigation into the Enhancement of Gas–Liquid Mass Transfer of Absorption of H2S by MDEA with Carbon Quantum Dots

“…The purification technology of H 2 S can be roughly divided into three types: dry oxidation, − wet oxidation, , and wet absorption. , Compared with wet oxidation, the absorption method does not need to add a catalyst, the sulfur capacity of the absorption solution is higher, and no blockage and abrasion of equipment and pipeline are caused by solid sulfur in the solution, which is less likely to cause operation failure . Alkanolamine desulfurization technology is widely used in gas purification due to its high H 2 S purification efficiency, large sulfur capacity, and other advantages.…”