Methods and systems for turbulent, corrosion resistant heat exchangers

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.