Drier Regeneration Process

• When moisture breakthrough occurs in driers D-362A/B, D-384A/B, or D-412A/B, the saturated drier is taken offline for regeneration.
• Regeneration uses a closed-loop system with ethylene pressurized by C-750 (Regeneration Gas Blower).

Regeneration Process

• C-750 sends ethylene to the shell side of E-760 (Regeneration Gas Heater).
• E-760 heats the ethylene using Dowtherm on the tube side.
• A spillback line is used during startup to maintain C-750's minimum flow.
• The hot gas goes to the spent drier to remove moisture from the desiccant.
• The gas returns to the shell side of E-750, where cooling water cools it.
• The cooled gas flows to D-750 (Regeneration Gas K.O. Drum) for phase separation.
• Liquid from D-750 is sent to D-353.
• Ethylene vapor from D-750 is routed back to C-750's suction.
• Excess gas can be routed back to D-360 during the early stages of regeneration.

E-750 (Regeneration Gas Cooler)

• E-750 cools and condenses the gas using cooling water.
• Cooling water runs through the tube side and regen gas flows through the shell side.
• It condenses the gas before it enters D-750.

D-750 (Regeneration Gas K.O. Drum)

• D-750 is 2 feet in diameter and 9 feet long.
• It has a demister pad inside, below the vapor outlet.
• Its purpose is to remove liquid from the gas after cooling.
• Regen gas enters the side, liquid exits the bottom, and ethylene vapor exits the top.

C-750 (Regeneration Gas Blower)

• C-750 is a standard centrifugal blower, powered by a 45 HP electric motor.
• It compresses the ethylene vapor to ensure flow through the regeneration system.

E-760 (Regeneration Gas Heater)

• E-760 heats the gas using Dowtherm.
• Dowtherm runs through the tube side and regen gas flows through the shell side.
• The heated gas is sent to driers D-362A/B, D-384A/B, or D-412A/B.