Reaction mechanism of a single calcium hydroxide particle with humidified HCl

Removal of chloride from MSWI fly ash

“…The XRD pattern shows that Ca(OH) 2 , CaCl 2 ·2H 2 O, and Ca(OH)Cl were present in the sample. Most of the studies reported in literature [11][12][13] assume that CaCl 2 ·2H 2 O and Ca(OH)Cl are both chlorinated products of the reaction between Ca(OH) 2 and HCl, according to the following equation:…”

Modeling dry-scrubbing of gaseous HCl with hydrated lime in cyclones with and without recirculation

“…A range of 1.0 × 10 −3 to 1.0 × 10 5 m s −1 was set for k s , and 1.0 × 10 −12 to 1.0 × 10 −7 m 2 s −1 for dif. The wide ranges selected for these parameters is related to the variability of values found in the literature for the reaction process consisting of calcium compounds/HCl [9,15,[24][25][26][27][28][29], depending on the system considered and the reaction conditions used.…”

“…At the exit of the cyclone concentrator there occur the same conditions found at the exit of the last CSTR in the concentrator for the gas and the solid flows, since the solid is not captured in this cyclone. At the exit of the cyclone concentrator the debit of B is: d ng out cc = n g out cc N cc tr cc (26) where tr cc is the average residence time of the gas in the cyclone concentrator, which is determined by the ratio between the cyclone concentrator volume (V cc ) and the gas flow through it (Q cc ).…”

Basic Study of the Reaction of Calcium Hydroxide with Hydrogen Chloride Using Single Crystals

“…In this process, calcium hydroxide (Ca­(OH) 2 ) is sprayed into the gas and then accumulates on the bag filter, where it reacts with HCl gas. This gas–solid reaction has been investigated in many studies. − To fully utilize the Ca­(OH) 2 sorbent, the ideal final product is CaCl 2 or any of its hydrates. However, it is known that the reaction of Ca­(OH) 2 with HCl under actual bag filter conditions is complex. The reaction is considered to involve at least two steps with CaOHCl or its hydrate as an intermediate .…”

“…These features make it difficult to comprehensively investigate the reaction mechanism of Ca­(OH) 2 with HCl. Furthermore, few reports ,− , have considered the reaction kinetics under actual bag filter conditions (e.g., temperature = 150–200 °C, HCl concentration = 0–1000 ppm, and high humidity).…”