Document LgyxvyO0d33k2eLgr8KD79o6z

APPROVED BY: DATE: FILE: SOP16TCE.SD +--------------------------------------------------+ ! TCE SECTION SHUTDOWN! +------------------------------- -------------+ The following shutdown desc. iption is based on the pre-sumption that the TCE section is being shutdown and cleared for maintenence or for a Trans production run. If it is only being shutdown for lack of feed or production room, the clearing of the system is not necessary. Operating levels can be left in the reflux drums and reboilers so that restarting the unit is faster, easier, and less expensive. 1. BLOCK THE FEED FROM TRIETHANE II TO THE HEAVIES STILL. REDUCE THE STEAM TO THE HEAVIES STILL FAIRLY SLOWLY SO THAT THE VDCM HIGH PRESSURE STEAM SRV DOES NOT RELIEVE. 2. REDUCE THE REFLUX ON THE HEAVIES STILL. CLOSE THE STRIPPER FEED VALVE. IF THE TCE SECTION IS BEING SHUT DOWN FOR A TRANS RUN, PUT THE STRIPPER BOTTOMS ON RECIRCULATION TO THE HEAVIES STILL AND EMPTY THE STRIPPER TO THE HEAVIES STILL. CLOSE AND BLOCK THE STRIPPER STEAM VALVE. CLOSE AND BLOCK THE HEAVIES STILL STEAM VALVE. IF THE TCE SECTION IS TO BE CLEARED,- CONTINUE TO PUMP THE HEAVIES STILL REFLUX DRUM TO THE STILL UNTIL EMPTY. THEN KILL THE REFLUX PUMP. 4. MONITOR THE HEAVIES STILL PRESSURE AS THE BOTTOMS IS PUMPED OUT. OPEN THE NITROGEN MAKEUP BYPASS IF NECESSARY. 5. AFTER THE BOTTOMS HAS BEEN PUMPED OUT, SHUT DOWN THE BOTTOMS PUMP AND BLOCK THE LCV. THE TCE STRIPPER REFLUX DRUM CAN BE PUMPED EMPTY IF NECESSARY THROUGH THE LIGHTS PURGE LINE. 6. AFTER THE TCE SYSTEM IS DOWN AND EMPTY, NITROGEN PURGE THE STILL BOTTOMS LINE TO THE PER TRI FEED TANKS (TETRA). THIS SEEMS TO REDUCE THE CHANCE OF PLUGGED LINES ON STARTUP. *END* SL 010584 confidential? ct to Protective Order of , Judicial District Court