Method for determining operating status of liquid phase gas-phase interaction columns

• US 5,974,887 A
• Filed: 09/26/1997
• Issued: 11/02/1999
• Est. Priority Date: 09/26/1997
• Status: Expired due to Fees

• Current Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Original Assignee: Exxon Research and Engineering Company (Exxon Mobil Corporation)
• Inventors: Johnsrud, David R., Sela, Uri, Cody, George Dewey
• Primary Examiner(s): Williams, Hezron
• Assistant Examiner(s): TRAN, THUY V
• Application Number:
  US08/938,348
• Time in Patent Office: 767 Days
• Field of Search: 73/579, 73/602, 73/609, 73/610, 73/613, 73/861.18, 73/861.21, 73/19.01, 73/19.03, 73/19.1, 201/1, 702/54, 702/56
• US Class Current: 73/602
• CPC Class Codes: B01D 3/4211 of columns

Abstract

The present invention is a non-intrusive method to determine the flow state or voidage in an apparatus that interacts a gas phase with a liquid phase. The flow state or voidage is determined by relating them to wall vibrations.

Claims

1. A method for the non-intrusive determination of the flow state of a gas phase interacting with a liquid phase in a structure comprising:

(a) measuring wall vibrations of said structure and then determining the power spectrum as a function of frequency, said wall vibration measurements being taken at one or more positions along the structure wall in the vertical direction;

(b) determining the area of the power spectrum which includes a resonance peak for each of said positions;

(c) correlating a change in said area of the power spectrum in said vertical direction with said flow state by comparing the power spectrum to the power spectrum of the position when the structure was operating efficiently.

2. The method of claim 1 wherein said structure is a distillation tower.

3. The method of claim 1 wherein said structure is a pipestill.

4. The method of claim 1 wherein said step of measuring wall vibrations is performed by using an accelerometer.

5. The method of claim 1 wherein said power spectrum is between 4000 and 8000 Hz.

6. A method for the non-intrusive determination of the voidage in a bubble column comprising:

(a) measuring wall vibrations of said structure and then determining the power spectrum as a function of frequency, said wall vibration measurements being taken at several positions along the structure wall in the vertical direction;

(b) determining the area of the power spectrum which includes a resonance peak for each of said positions;

(c) correlating a change in said area of the power spectrum in said vertical direction with said flow state with said voidage in said bubble tower.