Abstract: Carbon dioxide is widely reported as the most important anthropogenic greenhouse gas, it accounts for the greatest portion of the global warming. CO2 capture and utilization (CCU) are one of the leading technologies to capture and utilize CO2. In this connection, a spray tower is used to study the capture of CO2 from flue gas using NaOH solutions as the absorbing medium. The absorption efficiency of CO2 by the spray tower is compared using different molarity of absorbents, such as NaOH solutions, at varying flow rates and with different fuels (cow dung, wood stick & charcoal with kerosene) for generating flue gas in the controlled environment. The spray tower absorption process demonstrates good performance in CO2 capture. When using a 2 Molar concentration of NaOH solution and a flow rate of 200ml/min, the coconut shell as fuel and NaOH solution as the solvent shows excellent performance in the spray tower, reducing the inlet concentration of 894 ppm to an outlet concentration of 215ppm, with an efficiency of 76%. The absorbed CO2 in the rich solution from the spray tower is utilized for growing algae, with the aqueous absorbent solution flowing continuously through the spray tower and algae bioreactor. The absorption of CO2 by micro algae helps to reduce the energy consumption of CCU technology, resulting in savings in electric power and capital expenses. The overall CO2 removal efficiency of the spray tower, using NaOH as the absorbing solution is 76%. This process contributes to the reduction of CO2 emissions in the atmosphere and aids in mitigating global warming.
Ramakrishnan et al. (Tue,) studied this question.