EG

Question 1

What is the purpose of the EG Reactor system?

Answer 1

To create EC (ethylene carbonate in the EC RX
To create EG (ethylene glycol) in the EG RX

Question 2

What kind of reaction is the EC reaction

Answer 2

Exothermic

Question 3

What kind of reaction is the EG reaction

Answer 3

Endothermic

Question 4

Explain EC1 reactor

Answer 4

Converts ethylene oxide to ethylene carbonate
About 86% conversion

Feed streams:
- EO, Recycle CO2, water, EC1 recycle, Omega Catalyst

Question 5

Explain EC2 / GDR02 reactor

Answer 5

Continues ethylene carbonate reaction to:
~98.5%
- Higher temp than EC1

Question 6

Explain EC3 / GDR03

Answer 6

• Resonance time
• allows remaining EO to react with dissolved C02

Question 7

Explain GDD05

Answer 7

Separates the liquid recycle prior to EC2 RX

Question 8

Explain GDE08

Answer 8

• Keeps temps high enough to continue EO conversion in EC2
• 120 psi steam

Question 9

Explain GDD07 / C02 Separation Vessel

Answer 9

Separates free C02 from the product streams of EC2 RX
- some goes to TOX
- The rest goes back to GDC02

Question 10

Explain EG1 / GDR04 reactor

Answer 10

• converts ethylene carbonate and water to ethylene glycol and CO2
• EC conversion is about 90%
• kettle reactor
• runs about 290 psi
• 120# steam
• large amount of co2 released
• liquid level influences the residence time in the RX and the % of EC to EG conversion

Question 11

Explain EG2 / GDR05 reactor

Answer 11

• continues the EC conversion to virtually 100%
• runs around 29 psi
• open steam injected @ 120#

Question 12

Issues and Concerns from EC / EG side

Answer 12

• incomplete conversion = Meg quality issues
• Runaway reaction
• crystallization from reduced flow
• High pressure from EG1 to EG2
• Largest concentration of EO (except GBD06)

Question 13

Explain GDT01 / Glycol Dehydrator

Answer 13

• remove water and impurities from the MEG product stream
  - water goes overhead to WW
• column under Vacuum
• Bottoms contains mainly MEG / 93%
• temps over 140f glycol can boil up overhead / bad
• water can cause off spec MEG
• too high of temps can break down OMEGA cat

Question 14

Explain GDT02 / Glycol bleed flasher

Answer 14

Removes heavy glycols and sodium salts from glycol bleed stream

• under vacuum
• sodium coms from caustic injection
• if sodium is over 1% then its re-ran through tower
• heat tracing is critical to prevent fouling
• 40% surplus capacity

Question 15

Explain GDX02 / vacuum system

Answer 15

Maintains vacuum on the overheads of GDT01 / GDT02

• 200# steam
• non condensable are sent to TOX
• discharge is sent to GED03 then to WW

Question 16

Explain GDTK02 / container first flush sump tank

Answer 16

Collects storm water and potentially contaminated drains

• will trap the first 2” of contaminated water
• if no leaks or oil sheen can send to WW

Question 17

Explain the MEG purification system

Answer 17

• purify MEG to meet product specs
• Remove OMEGA and heavy glycols (deg, teg)
• entire process under vacuum
• damage to catalyst / keep around 324f
  *loss of vacuum
  *financial implications due to off spec MEG

Question 18

Explain the GET01 / Meg purification column

Answer 18

Receives bottoms stream from Dehydrator
Flashes off MEG and heavy glycols

• Bottom section: CSS
  
  • recovers OMEGA by flashing off glycols
  • 314* F to avoid thermal decomposition of OMEGA
  • 43% cat solution is recovered and recycled back to EC1
• Top section (pasteurizing section)
  
  • separates residual water and light components from MEG
  • contains Mellapack packing

Question 19

Explain GED01 / Meg polishing Vessel

Answer 19

• removes any traces of iron to improve the UV
• GEFIL04 / filter removes any further traces of iron before sent to rundown tank

Question 20

Explain GETK01 / glycol slops tank

Answer 20

Storage for glycol slops during:
-S/U and S/D
-off spec

• ATM tank with n2 blanket
• pumps to Glycol bleed flasher GDT02 if sodium is > 1ppm

Question 21

Explain GETK02 a/b

Answer 21

• Nitrogen blanket
• Fill one rundown tank for 72 hours, swap tanks, sample, certify, pump OSBL
• Product is sent OSBL, railyard, trucks or docks

Question 22

Explain GET03 / MEG side stripper

Answer 22

Further Removes MEG, sent back to GET01

-DEG and heavier go from 2% feed to 35-45% bottoms
- pulls from middle section of GET01
- overheads mostly vapor go back to GET01
-GEE05 reboiler controls temp via 200# steam

Question 23

Explain GET02 / Meg Recycle Column

Answer 23

Recovers residual MEG from the GET03 bottoms stream

• Top product is sent to GDT01 glycol dehydrator via GEP08
• Bottoms go to OSBL via GEP07 & GEFIL02, then cooled @ GEE08
• TEMP control via GEE07 reboiler 200# steam

Question 24

Explain GEX01 / vacuum system

Answer 24

• Maintains vacuum for columns in MEG purification / recycle system
• Vacuum allows low operations temp, this minimizes MEG degradation and omega catalyst thermal decomposition.
• # 200 steam powers multi stage ejectors system

Question 25

What 2 types of stream are in the OMEGA system

Answer 25

- concentrated catalyst solution - Dilute catalyst solution

Question 26

What two Components are in the OMEGA streams

Answer 26

* Component A: susceptible to thermal decomposition * Component B: susceptible to deactivation by chlorides

Question 27

Explain GDD08 / Catalyst Charge vessel

Answer 27

Used to store fresh and regenerated catalyst - makeup catalyst is sent from this vessel to process EG2 - LP n2 helps prevent degradation - during shutdowns the concentrated cat solution of the CSS is stored here

Question 28

Explain GDTK01 / Catalyst storage Tank

Answer 28

Used to store dilute OMEGA during unit shutdowns - large enough to store the entire system volume of the EG section plus one washing and flushing

Question 29

Explain GDD09 / catalyst drips vessel

Answer 29

Is used to collect the catalyst drain from process systems during shutdowns and equipment maintenance - pumps to GDTK01 - relief from other vessels

Question 30

Explain GUTK01 / chilled water storage tank

Answer 30

* Receives and stores chilled water for users * Absorb fluctuations in chilled water temp * Buffer capacity for stage storage during plant shutdown

Question 31

Explain GUD02 / Hot water Buffer Vessel

Answer 31

* Absorbs fluctuations in the water temp * Collects the circulated hot water from users GDE05, GBE11 * Make up condensate from GUD01 during start up or make up

Question 32

Explain the purpose of the Chillers / GUX01 A-J

Answer 32

to provide chilled water to users whose cooling requirements are not met by cooling water. - required to supply water at 50f - CHW is used to recover and condense EO - Cool lean absorbent so that it can absorb EO - Analyzer shelter * 10 chillers in parallel arrangement * Number of chillers in operation depend on demand and atmospheric conditions

Question 33

How do the Chillers work?

Answer 33

Absorption Refrigeration - operates on the principle of evaporating water at low pressure - Absorption in a lithium bromide solution -(strong absorbent for water) -(skin and eye irritant)

Question 34

What style of Trays are in GET01

Answer 34

Total Liquid Draw off

Question 35

What % (Meg, omega, other) are sent to GET01 / Meg Purification Column

Answer 35

Meg: 93% OMEGA: 6% DEG/other: 1%

Question 36

Explain GUD02. Hot water Users?

Answer 36

Closed circuit hot water Buffer vessel GDE05 GBE11 (removed)

Question 37

What does OMEGA stand for?

Answer 37

Only MEG advantage