Centrifugal pump for pumping a multiphase suspension and a gas removal device for use in a centrifugal pump

Patent metadata

Field	Value
Publication number	US-11953013-B2
Application number	US-202118038922-A
Country	US
Kind code	B2
Filing date	Oct 27, 2021
Priority date	Dec 21, 2020
Publication date	Apr 9, 2024
Grant date	Apr 9, 2024

Abstract

A centrifugal pump includes a pump housing having a suspension inlet and a suspension outlet and a flow channel between the inlet and the outlet, a shaft mounted by bearings for rotation about a center axis, an impeller which is rotatable by the shaft, in alignment with the inlet and arranged to be rotated about the axis in the flow channel, and gas collecting openings for gas removal arranged in the flow channel. The inlet end of the flow channel includes a number of static vanes comprising gas collecting openings, the vanes extend radially from an inner wall of the flow channel toward the center of the flow channel and are upstream of the impeller.

First claim

The invention claimed is:

1. A centrifugal pump for pumping a multiphase suspension containing liquid, solid material and gas, the pump comprising:
a pump housing having a suspension inlet and a suspension outlet and a flow channel between the inlet and the outlet;
a shaft mounted by bearings so as to be capable of rotating about an axis;
an impeller rotatable by the shaft, in alignment with the suspension inlet and arranged to be rotated about the axis in the flow channel;
gas collecting openings configured to remove gas arranged in the flow channel, an end of the flow channel at the inlet includes a number of static vanes comprising the gas collecting openings connected to gas channels extending through the static vanes, the static vanes extending radially from an inner wall of the flow channel toward a center of the flow channel, and the vanes disposed upstream of the impeller,
wherein the gas collecting openings are disposed at a trailing edge of a respective vane, and/or the gas collecting openings are provided at a backside of the respective vane, with respect to a flow direction when in use.

2. The centrifugal pump according to claim 1 , wherein the vanes have an annular, elliptical triangular or wing shaped outer cross section in a flow direction of the suspension.

3. The centrifugal pump according to claim 1 , wherein the gas collecting openings are disposed at a respective vane end facing radially towards the axis.

4. The centrifugal pump according to claim 1 , wherein the static vanes extend radially from a tubular element which is disposed at the end of the flow channel at the inlet.

5. The centrifugal pump according to claim 1 , wherein the vanes are attached to the pump housing at the end of the flow channel at the inlet.

6. The centrifugal pump according to claim 1 , wherein a rotatable inducer is arranged in a flow direction upstream of the vanes.

7. The centrifugal pump according to claim 6 , wherein the inducer and the impeller are rotatable by the shaft or by separate shafts or a rotating device.

8. The centrifugal pump according to claim 3 , wherein a gas collecting opening of the gas collecting openings is disposed at an end of the respective vane, a clearance is disposed between the vane end and the shaft for a gas bubble layer to enter to the clearance and to further enter the gas collecting opening.

9. The centrifugal pump according to claim 4 , wherein the tubular element comprises an annular ring or flange attachable to the pump housing.

10. The centrifugal pump according to claim 1 , wherein the gas collecting openings are connected to a system for collecting the gas.

11. The centrifugal pump according to claim 10 , wherein the system for collecting gas is configured to provide a pressure difference between the gas in the suspension and outside of the centrifugal pump.

12. The centrifugal pump according to claim 1 , wherein the pump is configured for multiphase suspension having, a consistency of cellulosic fibers of 0.1 to 18 weight % (wt %) or other multiphase suspension having a consistency of 0.1 to 20 wt %.

13. The centrifugal pump according to claim 1 , wherein the number of vanes is 1 to 6.

14. The centrifugal pump according to claim 1 , wherein the number of vanes is 2 to 4 vanes.

15. A gas removal device configured to be coupled to an inlet of a centrifugal pump, the gas removal device comprising:
a tubular element having a first axial end and a second axial end and a flow channel between the first and second axial ends;
static vanes extending radially from an inner wall of the flow channel toward the center of the flow channel, the static vanes including gas collecting openings connected to gas channels extending through the vanes, the gas removal device is configured to be located axially upstream of an impeller of the centrifugal pump,
wherein the gas collecting openings are disposed at a trailing edge of a respective vane, and/or the gas collecting openings are provided at a backside of the respective vane, with respect to a flow direction when in use.

Assignees

• Sulzer Management Ag

Inventors

• Titinen Kalle
• Ripattila Janne

Classifications

• F04D1/06 Primary

  Multi-stage pumps (F04D1/02, F04D13/10 take precedence) · CPC title

• F04D1/04

  Helico-centrifugal pumps · CPC title

• F04D9/003

  separating and removing the vapour · CPC title

• F05D2240/122

  related to the trailing edge of a stator vane · CPC title

• F05D2250/51

  Inlet · CPC title