A packed bed absorption tower produces carbonated water for beverages by continuously contacting a stream of...

 

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A packed bed absorption tower produces carbonated water for beverages by continuously contacting a stream of carbon dioxide (CO₂) gas with a stream of liquid water. Pure mountain spring water, containing no dissolved CO2, enters the top of the column at a flow rate of 5 kmol/min. Pure CO₂ gas at 2 atm is also fed in from the top of the tower at a flow rate of 1 kmol/min. As the water flows down the tower, CO₂ gas absorbs into the water, and the dissolved CO₂ increases down the length of the packed bed. The carbonated water and the unused CO₂ gas exit the bottom of the tower. pure water in packed bed of 1" ceramic rings 1 carbonated water out pure CO, in 2 atm 20°C unused CO, out The tower is packed with 1" ceramic rings and the tower's inner diameter is 0.25 m. The tempera- ture is maintained at 20 C. At this temperature, the Henry's law constant for CO₂ in water is 25.4 -9 m/s, density of liquid water is i atm/(kmol/m), mass diffusivity of dissolved CO, in water is 1.77 * 10 998.2 kg/m³, and dynamic viscosity of water is 9.93×10 kg(ms). 4 (a) What is the liquid phase capacity coefficient ka for CO₂ in water flowing through the packed bed? The following data is known: Packing 2.0 inch rings 1.5 inch rings 1.0 inch rings 0.5 inch rings 0.375 inch rings 1.5 inch saddles 1.0 inch saddles 0.375 inch saddles 3.0 inch spiral tiles a 80 90 100 280 550 160 170 150 110 11 0.22 0.22 0.22 0.35 0.46 0.28 0.28 0.28 0.28 (b) By performing an appropriate material balance, determine the height of packing if the desired concentration of dissolved CO₂ in the outlet water is 95% of saturation. State all the assumptions made. A packed bed absorption tower produces carbonated water for beverages by continuously contacting a stream of carbon dioxide (CO₂) gas with a stream of liquid water. Pure mountain spring water, containing no dissolved CO2, enters the top of the column at a flow rate of 5 kmol/min. Pure CO₂ gas at 2 atm is also fed in from the top of the tower at a flow rate of 1 kmol/min. As the water flows down the tower, CO₂ gas absorbs into the water, and the dissolved CO₂ increases down the length of the packed bed. The carbonated water and the unused CO₂ gas exit the bottom of the tower. pure water in packed bed of 1" ceramic rings 1 carbonated water out pure CO, in 2 atm 20°C unused CO, out The tower is packed with 1" ceramic rings and the tower's inner diameter is 0.25 m. The tempera- ture is maintained at 20 C. At this temperature, the Henry's law constant for CO₂ in water is 25.4 -9 m/s, density of liquid water is i atm/(kmol/m), mass diffusivity of dissolved CO, in water is 1.77 * 10 998.2 kg/m³, and dynamic viscosity of water is 9.93×10 kg(ms). 4 (a) What is the liquid phase capacity coefficient ka for CO₂ in water flowing through the packed bed? The following data is known: Packing 2.0 inch rings 1.5 inch rings 1.0 inch rings 0.5 inch rings 0.375 inch rings 1.5 inch saddles 1.0 inch saddles 0.375 inch saddles 3.0 inch spiral tiles a 80 90 100 280 550 160 170 150 110 11 0.22 0.22 0.22 0.35 0.46 0.28 0.28 0.28 0.28 (b) By performing an appropriate material balance, determine the height of packing if the desired concentration of dissolved CO₂ in the outlet water is 95% of saturation. State all the assumptions made.

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a Liquid Phase Capacity Coefficient kLa Calculation The liquid phase capacity coefficient kLa is a measure of the mass transfer efficiency in the absorption process It is given by the equation kLa 2 o... View the full answer