Acid
gas cleaning is one of the natural gas processing steps where
the acid gases are removed to satisfy the quality of the sweet gas.
Conventionally, this is achieved by processing the sour gas through
an acid gas removal (AGR) unit to produce the desired sweet gas while
concentrating the H2S gas in the acid gas enrichment unit.
Together with achieving the required high heating value of 930 BTU/SCF
in the sweet gas, it is also desired from the process that the acid
gases must contain 30–55% H2S content before feeding
to the sulfur recovery unit. In addition, the waste gases sent to
the thermal oxidizer must not contain more than 2000 ppmv H2S. However, these requirements put a constraint on the process operational
flexibility especially when the feed gas has a high CO2 content. In this study, a novel acid gas cleaning design has been
proposed that can significantly reduce the energy requirement while
maintaining all the streams’ design specifications. The proposed
design recommends first producing acid gas with the required purity
and then producing the sweet gas in another AGR unit. The results
show that the proposed design requires 22% lower operational energy
compared to the base design. The economic analysis reflects a saving
of more than $7.25 million in total annual cost compared to the conventional
design.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.