Experiments And Simulation Of CO₂Capture By Aqueous Ammonia

Since the Industrial Revolution, with the rapid development of all industriesand a large number of fossil fuels consumed, the content of carbon dioxide inthe atmosphere has been significantly increased. The increase of carbondioxide in the atmosphere brings the greenhouse effect, and raises thetemperature. As the temperature increasing, the disaster brought by globalwarming becomes more evident. Avoiding global warm has become theconsensus in the world. Reducing carbon dioxide emissions has been a goal ofthe entire industrial sectors. Therefore, separating carbon dioxide from the fluegas to reduce carbon dioxide emissions of coal-fired power plants has becomea research focus in recent years.In terms of energy consumption of the absorbent regeneration processes andthe CO₂capture capacity of the absorbent, the carbon dioxide captureprocesses using aqueous ammonia is better than the capture processes byamine. In this work, the CO₂capture processes using aqueous ammonia wasstudied by experiment and simulation. The method of simulation of the CO₂capture processes was verified by experiments. Absorption rate and ammonialoss rate are the two parameters to measure the absorption process. The impactof absorbent temperature, concentration, liquid to gas, flue gas temperature onthe absorption process was explored by simulation in this work. Ammonia volatilization could easily lead to the secondary pollution, whichis the main drawback of carbon dioxide capture from flue gas using aqueousammonia. In this study, an improved process was provided to avoid thisdrawback, i.e., CO₂capture from flue gas by aqueous ammonia in two stages.The improved process can enhance the absorption rate of the absorptionprocesses under the same process conditions and significantly reduceammonia loss rate. In addition, comparisons between CO₂capture from fluegas by aqueous ammonia in two stages and the traditional CO₂capture processwere provided.