1993 Volume 19 Issue 5 Pages 818-828
Separation of CO2 from the stack gas of plants that burn fossil fuels, followed by sequesterring it in ocean deeps or depleted oil fields is an important means for mitigating CO2 emission into the atmosphere. This paper presents 1) a discussion of the minimum energy requirement of CO2 separation integrated with power plants, and 2) a comparison of separation processes based on various principles, including absorption, adsorption, distillation, and crystallization, from the viewpoint of energy consumption. As the first step of the comparison, conventional processes were designed to examiae the substantial energy consumption structure and to determined energysaving policies via these processes.
Next, attempts to compare the different separation processes were made by designing optimum processes which adopted all the energy-saving policies that were considered to be practical in the near future. The most energy-saving type of process consumes energy as little as 2.6 times the thermodynamic minimum energy requirement. Ideally, none-energy consuming separation of CO2 from power plant stack gas is possible.
