Method for monitoring the level of an ethylene polymerization catalyst slurry

Patent metadata

Field	Value
Publication number	US-9050573-B2
Application number	US-201013514096-A
Country	US
Kind code	B2
Filing date	Dec 17, 2010
Priority date	Dec 18, 2009
Publication date	Jun 9, 2015
Grant date	Jun 9, 2015

Abstract

The present invention relates to a method for monitoring the level of an ethylene polymerization catalyst slurry in a mud pot ( 2 ), whereby said catalyst slurry is prepared by introducing a solid catalyst and a liquid diluent in said mud pot ( 2 ), and whereby through sedimentation an interface ( 35 ) is formed between said diluent and the obtained catalyst slurry, characterized in that said interface ( 35 ) is monitored with Time Domain Reflectometry.

First claim

The invention claimed is:

1. A method comprising:
preparing a catalyst slurry by introducing a solid catalyst and a liquid diluent in a mud pot, whereby through sedimentation an interface is formed between said liquid diluent and the obtained catalyst slurry, and wherein the catalyst slurry is an ethylene polymerization catalyst slurry; and
monitoring the level of the catalyst slurry in the mud pot by monitoring the level of said interface in the mud pot with Reflectometry using a reflectometer.

2. The method according to claim 1 , whereby said Reflectometry is also used for monitoring level of the liquid diluent in said mud pot.

3. The method according to claim 1 , whereby electromagnetic pulses are guided into said mud pot by at least two rigid or flexible conductors.

4. The method according to claim 1 , whereby said catalyst slurry is transferred to a mixing vessel for diluting said catalyst slurry to a concentration suitable for use in an ethylene polymerization reactor.

5. The method according to claim 1 , whereby said solid catalyst is a free-flowing catalyst.

6. The method according to claim 1 , whereby said liquid diluent is a hydrocarbon diluent.

7. The method according to claim 1 , whereby a pressure of between 4 barg and 16 barg is obtained in said mud pot by blanketing of said catalyst slurry with nitrogen.

8. A method comprising:
introducing a solid catalyst and a liquid diluent into a mud pot and allowing sedimentation of solid catalyst particles to form a catalyst slurry, wherein a solid-liquid boundary is formed between the catalyst slurry and the liquid diluent; and
measuring a level of the solid-liquid boundary in the mud pot with Domain Reflectometry using a reflectometer.

9. The method of claim 8 , wherein the Domain Reflectometry is Time Domain Reflectometry or Frequency Domain Reflectometry.

10. The method of claim 8 , wherein the Domain Reflectometry is Radar based Time Domain Reflectometry.

11. The method of claim 8 , wherein the Domain Reflectometry is Time Domain Reflectometry, wherein the Time Domain Reflectometry comprises measuring electromagnetic energy reflected from the solid-liquid boundary, and wherein the electromagnetic energy has a power of at most 2 Watt.

12. The method of claim 8 , further comprising measuring a level of the liquid diluent in the mud pot using Domain Reflectometry.

13. The method of claim 8 , wherein the solid catalyst has an angle of repose that is smaller than 38 degrees.

Assignees

• Fouarge Louis
• Brusselle Alain
• Total Res & Technology Feluy

Inventors

• Fouarge Louis
• Brusselle Alain

Classifications

• B01J8/228 Primary

  externally, i.e. the particles leaving the vessel and subsequently re-entering it · CPC title

• B01J2208/00769

  Details of feeding or discharging · CPC title

• C08F110/02

  Ethene · CPC title

• G01F23/284

  Electromagnetic waves · CPC title

• B01J8/20 Primary

  with liquid as a fluidising medium · CPC title