# US 2014/0150662 A1 · Methods and systems for turbulent, corrosion resistant heat exchangers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0150662 A1 - Document ID: US20140150662A1 - Status: Published application - Kind: A1 - Application number: 13/915,199 - Filed: 2013-06-11 - Published: 2014-06-05 - Earliest claimed: 2012-06-11 - Assignees: 7AC Technologies, Inc. - Applicants: 7AC Technologies, Inc. - Inventors: Peter F. Vandermeulen; Mark Allen; Arthur Laflamme - Web page: https://patentgrep.com/patent/US20140150662A1 ## CPC - F24F 3/1417: {with liquid hygroscopic desiccants} - B01D 53/18: Absorbing units; Liquid distributors therefor (B01D3/16, B01D3/26, B01D3/30 take precedence; packing elements B01J19/30, B01J19/32) - B01D 53/229: {Integrated processes (Diffusion and at least one other process, e.g. adsorption, absorption)} - B01D 53/263: {by absorption} - B01D 53/265: {by refrigeration (condensation)} - B01D 53/268: {by diffusion} - F28D 5/00: Heat-exchange apparatus having stationary conduit assemblies for one heat-exchange medium only, the media being in contact with different sides of the conduit wall, using the cooling effect of natural or forced evaporation - F28D 9/005: {the plates having openings therein for both heat-exchange media} - F28D 21/0015: {Heat and mass exchangers, e.g. with permeable walls} - F28F 1/02: Tubular elements of cross-section which is non-circular (F28F1/08, F28F1/10 take precedence) - F28F 13/12: by creating turbulence, e.g. by stirring, by increasing the force of circulation (F28F13/08 takes precedence) - F28F 19/02: by using coatings, e.g. vitreous or enamel coatings - F28F 21/065: {the heat-exchange apparatus employing plate-like or laminated conduits} - B01D 63/085: {specially adapted for two fluids in mass exchange flow} - B01D 2053/222: {with plates} - F24F 2003/1435: {comprising semi-permeable membrane} - F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02) - B01D: SEPARATION (separating solids from solids by wet methods B03B, B03D; by pneumatic jigs or tables B03B; by other dry methods B07; magnetic or electrostatic separation of solid materials from solid materials or fluids, separation by high-voltage electric fields B03C; centrifuges, vortex apparatus B04; presses per se for squeezing-out liquid from liquid-containing material B30B9/02; treatment of water C02F, e.g. softening by ion-exchange C02F1/42; {arrangements of air intake cleaners in gas turbine plants F02C7/05} ; arrangements or mounting of filters in air-conditioning, air-humidification or ventilation F24F13/28) - F28D: HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT (fluid heaters having heat generating means and heat transferring means F24H; furnaces F27; details of heat-exchange apparatus of general) - F28F: DETAILS OF HEAT-EXCHANGE AND HEAT-TRANSFER APPARATUS, OF GENERAL APPLICATION (water and air traps, air venting F16) ## Abstract Disclosed are various turbulent, corrosion-resistant heat exchangers used in desiccant air conditioning systems. ## Claims ### Claim 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, (b) two membranes, each facing an opposite side of the plate structure and spaced apart from the plate structure to define a gap therebetween through which a liquid desiccant can flow, and (c) at least one desiccant drain port, wherein each membrane has a bottom portion that is sealed to the plate structure such that liquid desiccant is forced to flow through the at least one drain port, thereby creating a negative pressure in the gap between each membrane and the plate structure. ### Claim 2 (depends on 1) The heat exchanger of claim 1, further comprising an air turbulator in each air gap between adjacent membrane-plate assemblies for inducing turbulence in the air flowing through the heat exchanger. ### Claim 3 (depends on 2) The heat exchanger of claim 2, wherein the air turbulator comprises a plastic netting material. ### Claim 4 (depends on 2) The heat exchanger of claim 2, wherein the air turbulator comprises a series of wires spanning across each gap between adjacent membrane-plate assemblies. ### Claim 5 (depends on 2) The heat exchanger of claim 2, wherein the air turbulator generates counter-rotating air flows through the air gap. ### Claim 6 (depends on 5) The heat exchanger of claim 5, wherein the air turbulator comprises a plurality of structures, each having a wall oriented at an angle to air flow through the air gap, said wall becoming progressively shorter in the direction or counter to the direction of the air flow to impart a rotational motion to air striking the wall. ### Claim 7 (depends on 6) The heat exchanger of claim 6, wherein pairs of adjacent structures are oriented to impart counter rotational motion to air flowing through the air gap. ### Claim 8 (depends on 7) The heat exchanger of claim 7, further comprising an obstruction between each pair of adjacent structures located downstream of said structures. ### Claim 9 (depends on 1) The heat exchanger of claim 1, wherein the membrane comprises polypropylene, Ethylene chlorotrifluoroethylene (ECTFE), polyethylene, polyolefin materials, cellulose acetate, Nitrocellulose, and cellulose esters (CA, CN, and CE), polysulfone (PS), polyether sulfone (PES), polyacrilonitrile (PAN), polyamide, polyimide, polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), or polyvinylchloride (PVC). ### Claim 10 (depends on 1) The heat exchanger of claim 1, wherein the membrane is a microporous membrane. ### Claim 11 (depends on 1) The heat exchanger claim 1, wherein each membrane is attached to a plate structure by an array of adhesive dots spaced across the membrane. ### Claim 12 (depends on 11) The heat exchanger of claim 11, wherein each adhesive dot is spaced apart from an adjacent adhesive dot by a distance between one-tenth to two times the width of an air gap. ### Claim 13 (depends on 1) The heat exchanger of claim 1, wherein each of said membrane-plate assemblies includes wicking material or screen material in the gap between the plate structure and each membrane. ### Claim 14 (depends on 13) The heat exchanger of claim 13, wherein the wicking material or screen material provides desiccant spreading, mixing, or turbulence to desiccant flowing through the gap between the plate structure and each membrane. ### Claim 15 (depends on 1) The heat exchanger of claim 1, wherein each plate structure comprises a thermally conductive rigid plastic material. ### Claim 16 (depends on 1) The heat exchanger of claim 1, wherein each plate structure comprises two spaced-apart supporting plates facing each other and having a gap therebetween through which a heat transfer fluid can flow. ### Claim 17 (depends on 16) The heat exchanger of claim 16, further comprising one or more spacers between the two spaced-apart supporting plates, each of said spacers including a fluid connection for draining a heat transfer fluid and a fluid connection for supplying or draining desiccant, said spacers comprising a compliant material coated with an adhesive. ### Claim 18 (depends on 17) The heat exchanger of claim 17, wherein the fluid connection for draining heat transfer fluid and the fluid connection for supplying or draining desiccant have separate seals such that a leak in a seal for one fluid connection does not affect the other fluid connection. ### Claim 19 (depends on 16) The heat exchanger of claim 16, wherein each plate structure further comprises a fluid seal between said supporting plates forming a channel configured to promote self-draining of the heat transfer fluid to at least one drain port. ### Claim 20 (depends on 16) The heat exchanger of claim 16, wherein the heat transfer fluid is water or a water/glycol mixture. ### Claim 21 (depends on 16) The heat exchanger of claim 16, further comprising a plastic mesh positioned in the gap between the two supporting plates in each plate structure for inducing turbulence in the heat transfer fluid. ### Claim 22 (depends on 21) The heat exchanger of claim 21, wherein the plastic mesh comprises a dual plane diamond mesh. ### Claim 23 (depends on 16) The heat exchanger of claim 16, wherein the two supporting plates in each plate structure are connected to each other by a series of adhesive dots arranged over internal surfaces of the supporting plates. ### Claim 24 (depends on 1) The heat exchanger of claim 1, wherein each of the membrane-plate assemblies includes a plurality of spaced desiccant supply and drain ports to provide a generally uniform distribution of desiccant through the gap between each membrane and the plate structure. ### Claim 25 (depends on 1) The heat exchanger of claim 1, wherein the plurality of membrane-plate assemblies are configured to permit airflow therethrough in a generally horizontal direction. ### Claim 26 (depends on 1) The heat exchanger of claim 1, wherein the plurality of membrane-plate assemblies are configured to permit airflow therethrough in a generally vertical direction. ### Claim 27 (depends on 1) The heat exchanger of claim 1, wherein seals used to seal the bottom portions of each membrane to the plate structure form channels configured to promote self-draining of the liquid desiccant to the at least one drain port. ### Claim 28 (depends on 1) The heat exchanger of claim 1, further comprising a spacer structure between adjacent membrane-plate assemblies, said spacer structure including side seals on opposite sides of the adjacent membrane-plate assemblies to provide an air seal, said spacer structure also including a plurality of spring elements extending between the side seals forming an air turbulator. ### Claim 29 (depends on 28) The heat exchanger of claim 28, wherein the side seals and spring elements comprise a molded plastic structure. ### Claim 30 (depends on 1) The heat exchanger of claim 1, wherein the membranes defining the air gap between each pair of adjacent membrane-plate assemblies form turbulator elements protruding into the air gap to create eddies and vortices in the air flowing through the air gap. ### Claim 31 (depends on 30) The heat exchanger of claim 30, wherein each membrane is supported by a screen structure between the membrane and a plate structure, and wherein the screen structure is shaped to form the turbulator elements in the membrane. ### Claim 32 (depends on 1) The heat exchanger of claim 1, further comprising an air mesh support structure in each air gap between adjacent membrane-plate assemblies for inducing turbulence in the air flowing through the heat exchanger and retaining the membranes in place on the plate structures. ### Claim 33 (depends on 32) The heat exchanger of claim 32, wherein the air mesh support structure includes an array of support structures for supporting the membranes and wires extending between the support structures for inducing air turbulence. ### Claim 34 (depends on 33) The heat exchanger of claim 33, further comprising endplates at opposite ends of the heat exchanger providing compressive forces on the plurality of membrane-plate assemblies. ### Claim 35 (depends on 1) The heat exchanger of claim 1, further comprising compliant spacers between adjacent membrane-plate assemblies, said spacers being compressible such that said plurality of membrane-plate assemblies may be pressed together to reduce the air gap between adjacent membrane-plate assemblies. ### Claim 36 (depends on 35) The heat exchanger of claim 35, wherein the compliant spacers are more compressed at one end of the membrane-plate assemblies than an opposite end, resulting in varying air gaps between adjacent membrane-plate assemblies. ### Claim 37 (depends on 36) The heat exchanger of claim 36, wherein the one end comprises an air entry end. ### Claim 38 (depends on 36) The heat exchanger of claim 36, wherein the one end comprises an air exit end. ### Claim 39 (depends on 36) The heat exchanger of claim 36, wherein each plate structure comprises two spaced-apart supporting plates facing each other and having a gap therebetween through which a cooling fluid can flow. ### Claim 40 (depends on 36) The heat exchanger of claim 36, wherein each plate structure comprises two spaced-apart supporting plates facing each other and having a gap therebetween through which a heating fluid can flow. ### Claim 41 (depends on 1) The heat exchanger of claim 1, wherein each plate structure comprises two spaced-apart supporting plates facing each other and having a gap therebetween through which a heat transfer fluid can flow, wherein the membranes cover only a portion of each plate structure and liquid desiccant flows across only said portion of the plate structure, and wherein heat transfer fluid flows across substantially the entire plate structure such that the airflow is dehumidified and cooled when flowing across the membrane, and only cooled when flowing across the plate structure not covered by the membrane. ### Claim 42 (depends on 41) The heat exchanger of claim 41, wherein the plurality of membrane-plate assemblies are configured to permit airflow therethrough in a generally horizontal direction. ### Claim 43 (depends on 41) The heat exchanger of claim 41, wherein the plurality of membrane-plate assemblies are configured to permit airflow therethrough in a generally vertical direction. ### Claim 44 (depends on 41) The heat exchanger of claim 41, wherein the heat transfer fluid flows in a counterflow direction relative to the air flow. ### Claim 45 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, (b) two membranes, each facing an opposite side of the plate structure and spaced apart from the plate structure to define a gap therebetween through which a liquid desiccant can flow, (c) at least one desiccant drain port, and (d) a siphoning drain, wherein liquid desiccant flows through the at least one drain port to the siphoning drain, thereby creating a negative pressure in the gap between each membrane and the plate structure.