received by the International Bureau on 18 May 2017 (18.05.2017)

1. An evaporative cooling system comprising:

a heat exchange medium for receiving cooling fluid to cool supply air flowing past the heat exchange medium;

a cooling fluid scarce for supplying fresh cooling fluid;

a supply line communicating with the cooling fluid source for supplying the cooling fluid to the heat exchange medium;

a return reservoir for collecting the cooling, fluid supplied to the heat exchange medium; and

a pump provided in the supply line for recirculating the cooling fluid collected in the reservoir into the supply line so as to provide recirculated cooling fluid along with fresh cooling fluid to the heat exchange medium.

2. The evaporative cooling system according to Claim 1 , wherein the heat exchange medium is provided in a direct evaporative cooling unit.

3. The evaporative cooling system according to Claim 1, further comprising a controller for controlling supply from the cooling fluid source.

4. The evaporative cooling system according to Claim 3, further comprising a sensor for sensing overflow from the return reservoir and providing a signal to the controller regarding the overflow.

5. The evaporative cooling system according to Claim 4, wherein the sensor senses a magnitude of the overflow from the return reservoir and provides the signal to the controller representing the magnitude of the overflow, the controller controlling cooling fluid supply from the cooling fluid source based on the magnitude of the overflow.

6. The evaporative cooling system according to Claim 5, wherein the controller controls a valve for the cooling fluid supply to reduce the cooling fluid supply from the cooling fluid source when the magnitude of the overflow is greater than a predetermined threshold.

7. The evaporative cooling system according to Claim 6, wherein the predetermined threshold is determined based on a flow rate of the cooling fluid supplied from the cooling fluid source.

8. The evaporative cooling system according to Claim 6, wherein the controller controls the valve for the cooling fluid supply by pulsing the valve to reduce the cooling fluid supply from the cooling fluid source.

9. The evaporative cooling system acoording to Claim 1, wherein the pump comprises an eductor or a venturi pump.

10. The evaporative cooling system acoording to Claim 1, wherein pressure from the fresh cooling fluid is used to create a motive force .in the pump to recirculate the cooling fluid.

1 1. A gas conditioning system comprising: a conditioning upit configured to condition a gas flowing therethrough, the conditioning unit utilizing a conditioning fluid to condition the Bowing gas;

a conditioning fluid source for supplying fresh conditioning fluid;

a supply line communicating with the conditioning fluid source for supplying the conditioning fluid to the conditioning unit;

a return reservoir if or collecting the conditioning fluid suppiied to the conditioning unit; and

a pump provided in the supply line for recirculating the conditioning fluid collected in the return reservoir into theisupply line so as to provide recirculated conditioning fluid along with fresh conditioning fluid to the conditioning unit.

12. The gas conditioning system according to Claim 11 , wherein the conditioning unit comprises a direct evaporative cooler utilizing a heat exchange medium.

13. The gas conditioning system according to Claim 11 , wherein pressure from the fresh conditioning fluid is used to create a motive force in the pump to recirculate the conditioning fluid.

14. (Amended) A method of cooling supply air in an evaporative cooling system, the method comprising:

supplying fresh cooling fluid from a cooling fluid source to a heat exchange medium through a supply line:

collecting at least a portion of the fresh cooling fluid supplied to and having passed through the heat exchange medium in a return reservoir; recirculating the collected cooling fluid to the supply line to be supplied along with the fresh cooling fluid; and

flowing the supply air through the heat exchange medium.

15. The method according to Claim 14, wherein the cooling fluid is recirculated through the heat exchangp medium using an eductpr or venturi pump.

16. The method according to Claim 14, further comprising controlling the flow rate of the fresh cooling fluid from the cooling fluid source.

17. The method according to Claim 14, further comprising sensing overflow from the return reservoir and providing feedback regarding the overflow.

18. The method according to Claim 17, further comprising controlling cooling fluid supply from the cooling fluid source based on the magnitude of the sensed overflow.

19. The method according to Claim 18, further comprising reducing the cooling fluid supply from the cooling fluid source when the magnitude of the overflow is greater than a predetermined threshold.

20. The method according to Claim 19, wherein the predetermined threshold is determined based on a fllbw rate of the cooling fluid supplied from the cooling fluid source.

21. (Amended!) The method according to Claim 14, wherein pressure irom the fresh cooling fluid is used to created a motive force to recirculate the cooling fluid.