Chemical Engineering Process Quiz

Spent Caustic Management Process

• Spent caustic from the bottoms of D-340 (Caustic Wash Settler) and D-345 (Continuous Skim Drum) is directed to T-344 (Degassing Tower), integrating additional spent caustic from Unit 1798.
• Overhead gases from T-344 are sent to the Purge Gas Header for further handling.
• In D-344 (Spent Caustic Settling Drum), spent caustic is introduced on the water side, ensuring proper separation and settling.

High-Level Management

• An intermittent process stream is diverted to D-344 from D-360 (Booster Cylinder Suction Drum) to mitigate potential system shutdowns of C-360A/B (Booster/Recycle Compressors) during high-level conditions.

Hydrocarbon and Slop Oil Routing

• The Slop Oil Header contributes its flow to D-344, facilitating the recovery of hydrocarbon materials.
• The bottom outlet of D-344 routes spent caustic through P-344 (Spent Caustic Transfer Pump) to the tube side of E-344A/B (Spent Caustic Coolers) for temperature regulation using cooling water on the shell side.

Recovery and Storage

• After cooling, the spent caustic is sent to storage in Unit 1791 TK-60 for future use or processing.
• Hydrocarbon, also exiting from the bottom of D-344, is transferred via P-345A/B (Hydrocarbon Recovery Pump) and/or P-346 (Hi Volume Hydrocarbon Recovery Pump) back to D-340 (Caustic Wash Settler) for further treatment.