Carbon dioxide removal by using Mg(OH)2 in a bubble column: Effects of various operating parameters

Accelerating Mineral Carbonation Using Carbonic Anhydrase

“…Flow rate has a significant impact on the CO 2 removal efficiency. As noted by Li et al, increased gas flow rate enhances turbulence and mixing, which in turn aids in gas–liquid transfer of CO 2 ; however, the increased flow rate decreases the brucite:CO 2 molar ratio and therefore decreases CO 2 removal efficiency. In addition to flow rate, CO 2 gas concentration has a dramatic effect on carbonation rates. , Geochemical modeling of experiments and those conducted by Harrison et al reveal that carbonation rates increase linearly with CO 2 flux (Figure B).…”

“…As noted by Li et al, increased gas flow rate enhances turbulence and mixing, which in turn aids in gas–liquid transfer of CO 2 ; however, the increased flow rate decreases the brucite:CO 2 molar ratio and therefore decreases CO 2 removal efficiency. In addition to flow rate, CO 2 gas concentration has a dramatic effect on carbonation rates. , Geochemical modeling of experiments and those conducted by Harrison et al reveal that carbonation rates increase linearly with CO 2 flux (Figure B). Clearly, carbonation rates can be accelerated by increasing CO 2 concentration in the gas stream, flow rates, hydration rates, and through various combinations of these processes.…”

“…Mineral carbonation is a promising strategy for sequestering CO 2 that involves the reaction of silicates, hydroxides, and oxides with CO 2 to form carbonate minerals. − Carbon storage within carbonate minerals is environmentally safe, reducing the need for poststorage monitoring. − Although mineral carbonation was originally envisaged as an industrial process operating at elevated temperatures and pressures (e.g., 185 °C, 150 atm), the costs for pretreatment, energy use, and chemical inputs (∼$50–300/t CO 2 ) far exceed current carbon prices (e.g., California Carbon Allowance ∼$13 US/t). ,− To minimize these costs, there has been considerable research into carbonation processes operating at low temperature and pressure conditions. − Aqueous carbonation of brucite [Mg­(OH) 2 ] has recently gained interest due to the fast reaction rates. ,,− The rate of CO 2 supply from the gas to the aqueous phase has been identified as the key rate limitation in the carbonation of highly reactive minerals such as brucite . This rate limitation can directly be addressed using CA .…”

Impacts of Particle Properties on Gas Holdup under Four Flow Regimes in Three‐Phase Bubble Columns

“…These dimensionless numbers are defined by Eqs. ( 4) and (5). The effects of gas velocity, liquid property, and particle properties (d p , r p , and V s ) are considered.…”

“…Gas-liquid-solid bubble columns are employed in the gas-toliquids technology to produce alternative energy, such as Fischer-Tropsch synthesis [1] and methanol synthesis using syngas [2]. Such reactors can also be utilized in heavy oil hydrocracking [3], carbon dioxide removal from flue gas [4][5][6], and used as photobioreactors for cultivating algae [7,8]. The fundamentals of the three-phase bubble column hydrodynamics are far from being well-known due to the multifaceted behavior of multiphase flows [9], different flow characteristics in the distinct flow regimes, and the complex effects of the particle properties and bubble behaviors [10].…”