Gas Processors Association Europe

John Carroll, Gas Liquids Engineering, Canada

Acid gas (CO2 and H2S) is a by-product of the sweetening of natural gas. Acid gas injection (AGI) is the compression of a low-pressure stream to sufficient pressure to achieve injection via a pipeline and injection well into a selected reservoir, making it environmentally friendly. AGI is a mature technology on a small- (< 10 MMSCFD) and medium-scale facilities (< 100 MMSCFD). The injection of CO2, either for sequestration or EOR, shares many characteristics with AGI and lessons learned are directly applicable.
The state of the art for AGI is reviewed. Newer projects with the injection of significantly larger volumes pose new challenges. The differences between small- and large-scale schemes are discussed, focusing on the surface facilities.