Methods and systems for turbulent, corrosion resistant heat exchangers

1. A heat exchanger for use in a desiccant air conditioning system, comprising:

a plurality of membrane-plate assemblies facing each other in a generally parallel arrangement and being spaced apart to define air gaps therebetween through which air to be treated by the desiccant air conditioning system can flow,

each of said membrane-plate assemblies comprising (a) a plate structure and (b) two membranes, each facing an opposite side of the plate structure and spaced apart from the plate structure to define a liquid gap therebetween through which a liquid can flow, and

wherein the membrane-plate assemblies have a cross-flow arrangement such that the air gaps alternatingly form primary and secondary channels, wherein air flow in the primary channels is at a cross flow to air flow in the secondary channel;

wherein each membrane has a bottom portion that is sealed to the plate structure such that liquid desiccant is forced to flow through one or more drain ports, thereby creating a negative pressure in the gap between each membrane and the plate structure.

2. The heat exchanger of claim 1 , further comprising a diverter for diverting at least a portion of the airflow exiting the primary channels to become part of the airflow entering the secondary channels to provide evaporative cooling.

3. The heat exchanger of claim 2 , wherein the diverter is configured to transport the diverted airflow to enter a portion of the heat exchanger near the entry of the primary channels.

4. The heat exchanger of claim 2 , wherein the diverter is configured to transport the diverted airflow to enter a portion of the heat exchanger near the exit of the primary channels.

5. The heat exchanger of claim 1 , wherein the primary channels are configured for vertical air flow.

6. The heat exchanger of claim 1 , wherein the primary channels are configured for horizontal air flow.

7. The heat exchanger of claim 1 , wherein the membranes defining the primary channels have a liquid desiccant flowing through the liquid gap.

8. The heat exchanger of claim 1 , wherein the membranes defining the secondary channels have water flowing through the liquid gap.

9. The heat exchanger of claim 8 , wherein the water comprises seawater or wastewater.

10. A heat exchanger for use in a desiccant air conditioning system, comprising:

a plurality of membrane-plate assemblies facing each other in a generally parallel arrangement and being spaced apart to define air gaps therebetween through which air to be treated by the desiccant air conditioning system can flow,

each of said membrane-plate assemblies comprising (a) a plate structure and (b) two membranes, each facing an opposite side of the plate structure and spaced apart from the plate structure to define a liquid gap therebetween through which a liquid can flow, and

wherein the membrane-plate assemblies have a cross-flow arrangement such that the air gaps alternatingly form primary and secondary channels, wherein air flow in the primary channels is at a cross flow to air flow in the secondary channel; and

a diverter for diverting at least a portion of the airflow exiting the primary channels to become part of the airflow entering the secondary channels to provide evaporative cooling.

11. The heat exchanger of claim 10 , wherein the diverter is configured to transport the diverted airflow to enter a portion of the heat exchanger near the entry of the primary channels.

12. The heat exchanger of claim 10 , wherein the diverter is configured to transport the diverted airflow to enter a portion of the heat exchanger near the exit of the primary channels.

13. The heat exchanger of claim 10 , wherein the primary channels are configured for vertical air flow.

14. The heat exchanger of claim 10 , wherein the primary channels are configured for horizontal air flow.

15. The heat exchanger of claim 10 , wherein the membranes defining the primary channels have a liquid desiccant flowing through the liquid gap.

16. The heat exchanger of claim 10 , wherein the membranes defining the secondary channels have water flowing through the liquid gap.

17. The heat exchanger of claim 16 , wherein the water comprises seawater or wastewater.