Technical paper
Strategies to Maximize Ethane Recovery with High-CO2 Feeds
Elevated feed-CO2 levels decrease the maximum ethane recovery in GSP and similar demethanizer configurations. This can be attributed to two causes. First, as CO2 displaces methane in the feed, the feed tends to behave more like a richer gas, which tend to have decreased ethane recoveries. Secondly, the choice of column operating conditions is complicated by the tendency of high-CO2 feeds to form dry ice in the upper sections of the column, or in the feed or residue lines. This often requires a sacrifice of ethane recovery to avoid dry ice formation. However, by manipulating column operating parameters, namely the vapor and liquid split to the subcooler, the column operating pressure, and the inlet split to the reboiler, the CO2 concentration profile in the column can be tailored to avoid dry ice formation, while still maximizing ethane recovery. This paper explores the effects of adjusting these operating parameters with both lean and rich feeds.
Elevated feed-CO2 levels decrease the maximum ethane recovery in GSP and similar demethanizer configurations. This can be attributed to two causes. First, as CO2 displaces methane in the feed, the feed tends to behave more like a richer gas, which tend to have decreased ethane recoveries. Secondly, the choice of column operating conditions is complicated by the tendency of high-CO2 feeds to form dry ice in the upper sections of the column, or in the feed or residue lines. This often requires a sacrifice of ethane recovery to avoid dry ice formation. However, by manipulating column operating parameters, namely the vapor and liquid split to the subcooler, the column operating pressure, and the inlet split to the reboiler, the CO2 concentration profile in the column can be tailored to avoid dry ice formation, while still maximizing ethane recovery. This paper explores the effects of adjusting these operating parameters with both lean and rich feeds.