Method for monitoring and controlling the operation of a pump station

1. A method for monitoring and controlling the operation of a pump station, wherein the pump station comprises a tank for temporary storage of a liquid, at least one pump configured for transporting the liquid away from the tank, and an outlet conduit connected to an outlet of the pump, wherein the outlet conduit of the pump station comprises a non-return valve, the method comprising the steps of:

a) determining the Geodetic head (Hgeo) of the pump station,

b) determining the pumped Flow (Q) for a given pump operation duty point,

c) determining the consumed Power (P) for the given pump operation duty point, and

d) determining a Normalized Specific Energy (nSE) of the pump station based on the determined values of Geodetic head (Hgeo), pumped Flow (Q), and consumed Power (P), wherein (nSE)=(P/Q)/Hgeo,

wherein the step of determining the Geodetic head (Hgeo) of the pump station includes the steps of:

a1) closing the non-return valve, and

a2) determining back pressure at a downstream side of the non-return valve.

2. The method of claim 1 , further comprising determining the Geodetic head (Hgeo) of the pump station based on the back pressure determined downstream of the non-return valve and a pressure difference corresponding to a difference in height position between the downstream side of the non-return valve and a liquid level in the tank.

3. The method of claim 1 , further comprising determining the Geodetic head (Hgeo) of the pump station based on the back pressure determined downstream of the non-return valve, a pressure difference corresponding to the difference in height position (Y) between the downstream side of the non-return valve and the outlet of the pump, and a pressure difference corresponding to a difference in height position between a liquid level in the tank and the outlet of the pump.

4. The method of claim 1 , further comprising determining the Geodetic head (Hgeo) of the pump station based on the back pressure determined downstream of the non-return valve, a pressure difference corresponding to a difference in height position (Y) between the downstream side of the non-return valve and the outlet of the pump, a pressure difference corresponding to a difference in height position (X) between a liquid level in the tank and a level sensor located in the tank, and a pressure difference corresponding to a difference in height position (Z) between the outlet of the pump and the level sensor located in the tank.

5. The method of claim 1 , wherein the pump station further comprises a pressure sensor located on the downstream side of the non-return valve.

6. The method of claim 5 , wherein the step of determining the back pressure downstream of the non-return valve comprises measuring the back pressure at the downstream side of the non-return valve using the pressure sensor when the non-return valve is closed.

7. The method of claim 6 , wherein the step of closing the non-return valve is performed by turning the pump OFF.

8. The method of claim 5 , wherein the step of determining the pumped Flow (Q) includes the steps of:

b1) measuring static pressure (Hmeasure) at the downstream side of the non-return valve using the pressure sensor when the pump is operated at the given pump operation duty point and is pumping liquid past the non-return valve, wherein a Static head (Hstat) of the pump is determined based on the measured static pressure (Hmeasure) and a pressure difference corresponding to a difference in height position between the downstream side of the non-return valve and a liquid level in the tank, and

b2) determining the pumped Flow (Q) by using the determined Static head (Hstat) of the pump from a predetermined pump-specific Q-Hstat-relationship.

9. The method of claim 5 , the step of determining the pumped Flow (Q) includes the steps of:

b1) measuring static pressure (Hmeasure) at the downstream side of the non-return valve using the pressure sensor when the pump is operated at the given pump operation duty point and is pumping liquid past the non-return valve, wherein a Static head (Hstat) of the pump is determined based on the measured static pressure (Hmeasure), a pressure difference corresponding to the difference in height position (Y) between the downstream side of the non-return valve and the outlet of the pump, a pressure difference corresponding to the difference in height position (X) between the liquid level in the tank and the level sensor located in the tank, and a pressure difference corresponding to the difference in height position (Z) between the outlet of the pump and the level sensor located in the tank, and

b2) determining the pumped Flow (Q) by using the determined Static head (Hstat) of the pump from a predetermined pump-specific Q-Hstat-relationship.

10. The method of claim 1 , wherein the step of determining the consumed Power (P) includes using the determined pumped Flow (Q) from a predetermined pump-specific Q-P-relationship.

11. The method of claim 1 , wherein the pump station further comprises a flowmeter located downstream of the at least one pump, wherein determining the pumped Flow (Q) includes obtaining measurement data from the flowmeter when the at least one pump is operated at the given pump operation duty point and is pumping liquid past the non-return valve.

12. The method of claim 1 , wherein the pump station further comprises a power meter and the step of determining the consumed Power (P) includes obtaining measurement data from the power meter when the at least one pump is operated at the given pump operation duty point and is pumping liquid past the non-return valve.

13. The method of claim 1 , wherein the pump station comprises a first pump station and the method further comprises:

determining values for the Normalized Specific Energy (nSE) for the first pump station over time, for at least the first pump station and a second pump station operating under a different set of environmental conditions than the first pump station, or for the first pump station and the second pump station over time; and

making at least one service, maintenance, or improvement decision relating to said first pump station or said second pump station based upon a comparison of the determined nSE values.

14. A non-transitory computer-readable storage medium having computer-readable program code portions embedded therein, the computer-readable program code portions configured to cause a computer to execute the method steps of claim 1 in order to determine the Normalized Specific Energy (nSE).

15. A pump station comprising:

a tank for temporary storage of a liquid;

at least one pump configured for transporting the liquid away from the tank;

an outlet conduit connected to an outlet of the pump, the outlet conduit comprising a non-return valve and a pressure sensor located on a downstream side of the non-return valve; and

a control unit configured for determining a Normalized Specific Energy (nSE) of the pump station based on determined values of Geodetic head (Hgeo) of the pump station, pumped Flow (Q) for a given pump operation duty point, and consumed Power (P) for the given pump operation duty point, wherein (nSE)=(P/Q)/Hgeo.

16. The pump station of claim 15 , wherein the at least one pump is arranged in the tank.

17. The pump station of claim 15 , further comprising a flowmeter located downstream of said at least one pump.

18. The pump station of claim 15 , wherein the control unit is configured for at least partly controlling said at least one pump based on measurement data received from the pump station.