Podcast
Questions and Answers
Explain the purpose of the aluminum balls placed on top of the catalyst bed in reactors R-411A/B.
Explain the purpose of the aluminum balls placed on top of the catalyst bed in reactors R-411A/B.
The aluminum balls serve as a guard bed to protect the catalyst bed from fouling or damage, ensuring even distribution of the hexene flow.
Describe what happens to the C6 purge/C6 bottoms stream from the bottom of T-411, including the equipment involved and the purpose of the step.
Describe what happens to the C6 purge/C6 bottoms stream from the bottom of T-411, including the equipment involved and the purpose of the step.
The C6 purge stream from T-411 flows to the shell side of E-414 (Hexene Purification Column Reboiler) and is heated with 100 psig steam. The overhead vapor from E-414 returns to T-411, aiding in temperature control.
If the nitrogen blanket pressure in D-413 drops below 10 psig, what potential issue could arise, and how might this affect the hexene?
If the nitrogen blanket pressure in D-413 drops below 10 psig, what potential issue could arise, and how might this affect the hexene?
If the nitrogen blanket pressure drops too low, air and moisture could contaminate the hexene, leading to potential degradation or unwanted side reactions. Maintaining the nitrogen blanket ensures the hexene remains dry and reduces risk flammability.
Explain why the overhead vapor from T-411 is routed to E-408 for cooling and then to D-411, detailing the purpose of each step.
Explain why the overhead vapor from T-411 is routed to E-408 for cooling and then to D-411, detailing the purpose of each step.
Explain the purpose of using activated alumina as catalyst and how it alters the composition of the hexene stream in reactors R-411A/B.
Explain the purpose of using activated alumina as catalyst and how it alters the composition of the hexene stream in reactors R-411A/B.
Flashcards
D-413 Function
D-413 Function
Vessel that receives hexene from various sources, maintained with a nitrogen blanket at 10-15 psig.
R-411A/B Reaction
R-411A/B Reaction
The chemical reaction in R-411A/B transforms ethyl-vinylidene to 3-methyl-pentene compounds.
E-407 Function
E-407 Function
Cools the hexene reactor effluent using cooling water before it enters T-411.
T-411 Function
T-411 Function
Signup and view all the flashcards
E-414 Function
E-414 Function
Signup and view all the flashcards
Study Notes
- Hexene from D-412A/B and Unit 1798 goes to the top of D-413, which is kept under a 10-15 psig nitrogen blanket.
- P-406A/B (Hexene Reactor Charge Pumps) move hexene from the bottom of D-413 to the tube side of E-406 (Hexene Reactor Preheater).
- E-406 heats the hexene using 60 psig steam on the shell side; condensate goes to D-415 and then to the Steam Condensate Header.
- Heated hexene flows to the bottom of R-411A/B (Hexene Reactors) and moves upward through a catalyst bed of activated alumina, which has a two-foot guard bed of aluminum balls on top.
- Ethyl-vinlydene converts to 3-methyl-pentene compounds as the hexene travels through the catalyst bed.
- The boiling point of these components increases, allowing them to be distilled out of the hexene product in T-411.
- Effluent from R-411A/B goes to the shell side of E-407 (Hexene Purification Column Feed Cooler) and is cooled by cooling water, then routed to T-411.
- In T-411, the effluent separates into three streams: an overhead vapor (99% 1-hexene), a side-draw (high-purity 1-hexene product), and a bottom liquid (C6 purge/bottoms).
- The T-411 overhead vapor goes to the shell side of E-408 (Hexene Purification Column Condenser) and is cooled by cooling water.
- Condensed vapor from E-408 goes to D-411 (Hexene Purification Column Reflux Drum); any water separates and goes to D-433, while gas vents to D-531.
- P-411A/B (Hexene Purification Column Reflux Pumps) sends liquid from D-411 back to T-411 as reflux or to T-380 as recycle.
- The T-411 side-draw stream is routed to the shell side of E-409 (Hexene Purification Column Product Cooler) by P-412A/B (Hexene Purification Column Product Pumps) and is cooled before being sent to C6 Product Tanks (TK-36/TK-37/TK-1806).
- The T-411 bottom liquid stream is routed to the shell side of E-414 (Hexene Purification Column Reboiler) and heated by 100 psig steam.
- Overhead vapor from E-414 goes back to T-411 for temperature control; steam condensate from E-414 goes to D-414 (Condensate Drum).
- P-414A/B (Condensate Pumps) pump the condensate from D-414 to the Steam Condensate Header.
- P-413A/B (Hexene Purification Column Bottoms Pumps) sends the liquid bottoms from T-411 to Unit 1191.
Equipment Details
- D-413 (Hexene Purification Surge Drum): 5’D x 9’8”L, ensures constant feed to R-411A/B.
- P-406A/B (Hexene Reactor Charge Pumps): Single-stage centrifugal pumps (30 HP, 3600 RPM), route hexene to R-411A/B.
- E-406 (Hexene Reactor Preheater): Shell and tube exchanger, preheats hexene feed with 60 psig steam.
- D-415 (Hexene Reactor Preheater Condensate Pot): 1’6”D x 4’6”L, receives condensate from E-406.
- R-411A/B (Hexene Reactors): 4’6”D x 32’2”L fixed-bed, up-flow reactors with activated alumina and a two-foot guard bed of aluminum balls which increases the boiling point of 3-methyl-pentene compounds.
- R-411A/B operates with one reactor online and one on standby and run-time is determined by the temperature of E-406 effluent
- E-407 (Hexene Purification Tower Feed Cooler): Shell and tube exchanger, cools hexene feed to enhance separation in T-411.
- T-411 (Hexene Purification Tower): 8’D x 119’L, purifies hexene to ≥99.0% purity, removing butene, saturates, and heavy contaminants.
- E-408 (Hexene Purification Tower Condenser): Shell and tube exchanger, cools and condenses overhead vapor from T-411 for reflux.
- D-411 (Hexene Purification Tower Reflux Drum): 6’D x 13’8”L, separates reflux liquid and recycle from non-condensable vapor and process water.
- P-411A/B (Hexene Purification Tower Reflux Pumps): Single-stage centrifugal pumps (100 HP, 3600 RPM), circulate reflux to T-411 and recycle to T-380.
- E-409 (Hexene Purification Tower Product Cooler): Hairpin heat exchanger, cools C6 product before storage.
- P-412A/B (Hexene Purification Tower Product Pumps): Single-stage centrifugal pumps (7.5 HP, 3600 RPM), route C6 product to storage.
- E-414 (Hexene Purification Tower Reboiler): Kettle-type reboiler, heats T-411 bottoms with 100 psig steam to create vapor.
- D-414 (Condensate Drum): 3’6”D x 8’L, collects condensate from E-414.
- P-414A/B (Condensate Pumps): Single-stage centrifugal pumps (20 HP, 1800 RPM), route condensate from D-414 to the Steam Condensate Header.
- P-413A/B (Hexene Purification Tower Bottoms Pumps): Single-stage centrifugal pumps (.5 HP, 1800 RPM), route liquid bottoms from T-411 to Unit 1191.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
