China
Africa
Explore chapters and articles related to this topic
Mass Transfer
Published in C. Anandharamakrishnan, S. Padma Ishwarya, Essentials and Applications of Food Engineering, 2019
C. Anandharamakrishnan, S. Padma Ishwarya
Carbonation is the process of dissolving carbon dioxide into a solution of water under pressure. Carbonated soft drinks are packaged in bottles or cans under high pressure in a chamber filled with carbon dioxide gas. In a carbonated beverage industry, Henry’s law can be applied to determine the pressure level to attain the required level of carbonation, if the required amount of CO2 (total number of moles) to be incorporated in the soft drink is known and vice versa. Example 6.1 explains the practical application of Henry’s law in beverage processing.
Concurrent modelling of carbonation and chloride-induced deterioration and uncertainty treatment in aging bridge fragility assessment
Published in Structure and Infrastructure Engineering, 2020
Mohamed Mortagi, Jayadipta Ghosh
The carbonation process, in essence, refers to the reaction of the carbon dioxide or CO2 molecule to generate carbonates, bicarbonates, and carbonic acid. In concrete structures, the carbon dioxide reacts with the hydrated cement paste yielding acidic products that lead to reductions in the pore-solution pH. When acting alone, and given a long enough exposure scenario, the carbonation process (without any chloride influence) may lead to pH level drop to an extent that may initiate corrosion of the reinforcing bars (Bertolini et al., 2004; Geng et al., 2016). However, such exposure times are on an average substantially long for reinforced concrete (RC) structures with modest cover depth to be of appreciable concern for deterioration during the design life (Li, 2017; Yoon et al., 2007). Of particular relevance, however, is one secondary effect of carbonation that potentially heightens the chloride-induced severity. This effect can be attributed to an increase in the solubility of Friedel’s salt in concrete as a consequence of pH drop due to carbonation leading to release of bound chlorides into the pore-solution phase (Geng et al., 2016; Kayyali & Haque, 1988; Kayyali & Qasrawi, 1992; Suryavanshi & Swamy, 1996; Wang et al., 2017; Zhu, Zi, Cao, et al., 2016).
The usage of rankinite for carbon capture and storage and carbonation kinetics
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2018
Hongwei Zhang, Jianan Chen, Rong Shao, Qinfang Zhang, Bao Lu, Gui Xia, Guihua Hou, Zhi Yun
To determine the ignition loss, the carbonated powder was removed. Then, we obtained the calculated carbonation degree as shown in Figure 9. The carbonation degree increased with increasing temperature. A peak temperature was obtained, as shown in Figure 9(a), when the temperature reached 363.15 K or 90°C. When the temperature increases, carbonation degree would be weakened, because the CO2 in the reactor first reacted with H2O in the reaction chamber through reaction equation (3) to form H2CO3. H2CO3 will generate CO32-ion through equation (4) due to the instability. CO32-ion reacted wit 3CaO·2SiO2 reacted to obtain CaCO3 precipitation. When the temperature is higher than 363.15 K, most of the moisture exists in a gas state, and a sufficient liquid phase cannot be provided for the carbonation reaction. Furthermore, as the temperature increases, the Henry constant of CO2 increases, in other words, the solubility of CO2 decreases. The amount of dissolved CO2 in water decreases with increasing the temperature leading to lower the carbonation degree. The kinetic constants of Eq. (3) and (4) can affect the carbonation of the powder C3S2, because C3S2 reacts with the carbonate ions in the aqueous phase instead of directly reacting with CO2 to produce calcium carbonate precipitates. The kinetic constants of Eq. (3) and Eq. (4) affect the volume of production of carbonate ions and then affect the carbonation process. The main factors affecting the kinetic constant are pressure, temperature, and the rate of CaCO3 production. These three factors are easy to determine. In fact, the influence of the equilibrium constant is considered. We attributed the influence of the kinetic constants of Eq. (3) and Eq. (4) to the carbonation of C3S2 when establishing the equation.