An Overview of Technologies for Separating and Concentrating CO_2 from Mixed Gas Streams

摘要

There are a number of techniques available to separate CO_2 from gas streams, someof which work well for low volume streams and others that are more suited for highvolume streams. Similarly, some of the techniques are more suited to dilute streams andothers more suited to concentrated streams. Often it is necessary to use more than oneprocess due to the increase in capital cost for a given process as the CO_2 concentrationdecreases. The paper discusses the most likely options presently identifiable for CO_2separation and capture: physical and chemical absorption, physical and chemicaladsorption, membranes, mineralization and biomineralization, cryogenic or lowtemperaturedistillation, and uptake by vegetation. These options were identified andincluded as probable options due to process simplicity, environmental impact, andeconomics. In some instances, the separation and capture methods are also sequestrationmethods, (e.g., vegetation uptake and some mineralization schemes), and are alsoincluded.