Sludge management system for crude oil storage tanks

Patent metadata

Field	Value
Publication number	US-10384242-B2
Application number	US-201615066925-A
Country	US
Kind code	B2
Filing date	Mar 10, 2016
Priority date	Mar 10, 2015
Publication date	Aug 20, 2019
Grant date	Aug 20, 2019

Abstract

A crude oil storage tank includes a bottom wall, a peripheral wall and a top wall that collectively define a storage volume. A first nozzle is arranged at the peripheral wall. The first nozzle is configured to selectively rotate between a first position and a second position to direct a first stream of fluid into the storage volume. A second nozzle is arranged at the peripheral wall. The second nozzle is configured to selectively rotate between a first position and a second position to direct a second stream of fluid into the storage volume.

First claim

What is claimed is:

1. A multi-stage method of reducing sludge deposition in a storage tank, said storage tank comprising a) a bottom wall, b) a peripheral wall, and c) a top wall that collectively define a storage volume, d) a first nozzle arranged at a first inlet through said peripheral wall at a first height, the first nozzle being configured to selectively rotate between a first position and a second position to direct a first stream of fluid into the storage volume, and e) a second nozzle arranged at a second inlet through said peripheral wall at said first height, the second nozzle being configured to selectively rotate between a first position and a second position to direct a second stream of fluid into the storage volume;
said method comprising:
during a first stage, directing first and second streams of fluid into said storage volume along a radius of said storage tank to dislodge sludge that lies centrally;
during a second stage, directing first and second streams of fluid into said storage volume at first and second angles to induce a rotational flow in storage tank to dislodge sludge that lies on said bottom wall;
during a third stage, directing first and second streams of fluid into said storage volume storage volume at third and fourth angles, opposite said first and second angles respectively, to induce a counter-rotational flow in said storage tank to further dislodge sludge that lies on said bottom wall; and
removing dislodged sludge from said storage tank.

2. The method of claim 1 , wherein said first and second streams of fluid are introduced at a velocity of about 15 m/s up to a velocity of about 27.4 m/s.

3. The method of claim 1 , wherein said first, second and third stages vary in duration and number.

4. The method of claim 3 , wherein said first and second streams of fluid are introduced at a velocity of at least about 15 m/s up to a velocity of about 27.4 m/s.

5. A multi-stage method of reducing sludge deposition in a storage tank, said storage tank comprising:
a) a bottom wall;
b) a peripheral wall; and
c) a top wall that collectively define a storage volume;
d) a first nozzle arranged at a first inlet through said peripheral wall at a first height, the first nozzle being configured to selectively rotate between a first position and a second position to direct a first stream of fluid into the storage volume; and
e) a second nozzle arranged at a second inlet through said peripheral wall at said first height and 120° from the first nozzle, the second nozzle being configured to selectively rotate between a first position and a second position to direct a second stream of fluid into the storage volume;

said method comprising:
i) during a first stage, directing first and second streams of fluid into said storage volume along a radius of said storage tank to dislodge sludge that lies centrally;
ii) during a second stage, directing first and second streams of fluid into said storage volume at first and second angles to induce a rotational flow in storage tank to dislodge sludge that lies on said bottom wall;
iii) during a third stage, directing first and second streams of fluid into said storage volume storage volume at third and fourth angles, opposite said first and second angles respectively, to induce a counter-rotational flow in said storage tank to further dislodge sludge that lies on said bottom wall; and
iv) removing dislodged sludge from said storage tank.

6. The method of claim 5 , wherein the first and second angles are 60° and 75° and the third and fourth angles are 75° and 60°.

Assignees

• Conocophillips Co

Inventors

• Das Sandipan Kumar
• Thomas Sally Ann

Classifications

• B08B9/0933 Primary

  Removing sludge or the like from tank bottoms · CPC title