C6-C10 Tower Operation

• C6+ feed goes to the top of D-401 (C6-C10 Tower Feed Coalescer).
• Entrained water in D-401 drops into a containment boot and goes to D-353.
• C6+ feed exits D-401 and goes to the tube side of E-401 (C6-C10 Tower Feed Preheater).
• In E-401, the C6+ feed is heated by 100 psig steam on the shell side.
• E-401 is not needed if the feed comes directly from T-380 bottom.
• Heated C6+ feed goes to the tube side of E-403 (C6-C10 Tower Feed Vaporizer).
• In E-403, the C6+ feed is partially vaporized by 400 psig steam on the shell side.
• The partially vaporized C6+ feed goes to T-400.
• In T-400, the feed is separated into an overhead vapor stream (C6-C10) and a bottom liquid stream (C12-C30+).
• The T-400 overhead vapor stream goes to the shell side of E-400 (C6-C10 Tower Condenser).
• In E-400, the vapor is cooled by cooling water on the tube side.
• Condensed vapor from E-400 goes to the bottom of D-400 (C6-C10 Tower Reflux Drum).
• Any entrained water in D-400 separates and goes to D-433 (Process Water Surge Drum).
• Non-condensable vapor from D-400 is vented to D-531 (Vent Header K.O. Drum).
• P-400A/B (C6-C10 Tower Reflux & Product Pumps) route liquid from D-400 back to T-400 as reflux or to T-410 (C6 Tower) as feed.
• The T-400 bottom liquid stream is routed to the shell side of E-405 (C6-C10 Tower Reboiler).
• In E-405, the liquid is heated by Dowtherm on the tube side.
• Vapor from E-405 is routed back to the bottom of T-400 for temperature control.
• P-405A/B (C6-C10 Tower Bottom Pumps) route the liquid bottom from E-405 to T-430 (C12-C24 Tower) as feed.

Equipment Details

• D-401 (C6-C10 Tower Feed Coalescer), removes water from the product stream, dimensions are 2’D x 9’L.
• E-401 (C6-C10 Tower Feed Preheater) heats the C6+ feed to T-400, using 100 psig steam.
• E-403 (C6-C10 Tower Feed Vaporizer) vaporizes the C6+ feed to T-400, using 400 psig steam.
• T-400 (C6-C10 Tower) separates C6-C10 from C12-C30+, dimensions are 5’D x 72’3”H.
• T-400 keeps C12 concentration in the overhead and C10 concentration at the bottoms within specification.
• C6+ feed enters the side of T-400, C6-C10 exits the top, and C12-C30+ exits the bottom.
• E-400 (C6-C10 Tower Condenser) cools and condenses overhead vapor from T-400.
• D-400 (C6-C10 Tower Reflux Drum) separates liquid for reflux to T-400 and feed for T-410 from non-condensable vapor, dimensions are 4’D x 20’L.
• Water collected in D-400 is sent to D-430.
• P-400A/B (C6-C10 Tower Reflux & Product Pumps) circulate reflux to T-400 and routes feed to T-410, using single-stage centrifugal pumps driven by 20 HP 3550 RPM motors.
• E-405 (C6-C10 Tower Reboiler) boils bottoms into a vapor.
• E-405 is a kettle-type reboiler that heats T-400 bottoms with Dowtherm.
• Vapor goes out of E-405 top nozzle, and remaining liquid goes out the bottom nozzle.
• P-405A/B (C6-C10 Tower Bottom Pumps) route liquid bottom to T-430 as feed, using single-stage centrifugal pumps driven by 20 HP 3550 RPM motors.