Saudi Aramco’s Berri Gas Plant department (BGP) has successfully commissioned and started-up a new, more efficient ethane liquefaction exchanger at the Ethane and NGL Recovery plant.
The new liquefaction heat exchanger has permanently replaced BGP’s existing ethane liquefaction unit and is the latest in their efforts to increase plant energy efficiency.
Aramco said its older ethane liquefaction system was complex, consisting of 30 pieces of equipment and two big compressors to reach the required conditions for the ethane liquefaction system.
“This system was hard to operate and costly to maintain due to the quantity of instruments and the age of rotating equipment,” it added.
The old system also negatively impacted the environment by flaring 4mn standard cubic feet per day (scfd) of ethane due to recycle compressor trips. The liquefaction rate was also limited to 20mn metric scfd.
Aramco said BGP recognised an opportunity to improve its ethane liquefaction process and minimize energy consumption by integrating the ethane and NGL recovery plant (Plant F-20) with the liquefaction process.
The initiative uses the available cryogenic process stream from de-methanizer overhead (-160° F) to liquefy ethane product. A side slip stream of de-methanizer overhead exchanges heat with the ethane product from the de-ethanizer reflux drums using a brazed aluminum heat exchanger (BAHE).
The new system is capable of producing 25mn metric scfd of liquid ethane along with keeping ethane outlet temperature as low as -105°F by maintaining methane gas inlet flow.
