Multi-Stream Microchannel Device

Abstract

Provided is a process and device for exchanging heat energy between three or more streams in a microchannel heat exchanger which can be integrated with a microchannel reactor to form an integrated microchannel processing unit. The combining of a plurality of integrated microchannel devices to provide the benefits of large-scale operation is enabled. In particular, the microchannel heat exchanger enables flexible heat transfer between multiple streams and total heat transfer rates of about 1 Watt or more per core unit volume expressed as W/cc.

1 . An apparatus, comprising:
 a first microchannel, having an inlet thereto and an outlet therefrom;   a second microchannel, having an inlet thereto and an outlet therefrom; and   at least a third microchannel, having an inlet thereto and an outlet therefrom, wherein each inlet and each outlet is distinct from the other inlets or outlets, respectively.   
     
     
         2 . The apparatus of  claim 1 , further comprising:
 a plurality of first microchannels, each first microchannel having an inlet thereto and an outlet therefrom;   a plurality of second microchannels, each second microchannel having an inlet thereto and an outlet therefrom; and   a plurality of at least third microchannels, each at least third microchannel having an inlet thereto and an outlet therefrom, wherein each inlet and each outlet is distinct from the other inlets or outlets, respectively.   
     
     
         3 . The apparatus of  claim 1 , further including a fluid flowing in the first microchannel, the fluid having a Reynolds number of less than about 4,000. 
     
     
         4 . The apparatus of  claim 1 , wherein the IPHTAP of at least one microchannel is about 30 or greater. 
     
     
         5 . The apparatus of  claim 1 , wherein at least one microchannel has at least one internal dimension of width or height of about 0.1 mm or less. 
     
     
         6 . The apparatus of  claim 1 , wherein when a first fluid flows through the first microchannel, the IPHTAP is about 30 or greater. 
     
     
         7 . The apparatus of  claim 6 , wherein when a first fluid is flowing through the first microchannel, a second fluid is flowing through the second microchannel, and an at least third fluid is flowing through the at least third microchannel, the total thermal power density is greater than 1 W/cc. 
     
     
         8 . The apparatus of  claim 1 , wherein the first microchannel has a hydraulic diameter different from at least the second microchannel. 
     
     
         9 . The apparatus of  claim 8 , wherein when a first fluid flows through the first microchannel, a second fluid flows through the second microchannel, and an at least third fluid flows through the at least third microchannel, the IPHTAP of at least one microchannel is about 10 or greater. 
     
     
         10 . The apparatus of  claim 1 , further comprising:
 a first surface;   a second surface, in a substantially opposing and spaced-apart relation to the first surface;   a third surface, in a substantially orthogonal relation to the first surface and to the second surface; and   a fourth surface, in a substantially opposing and spaced-apart relation to the third surface, wherein:
 the first microchannel defines a passageway between the first surface and the second surface; 
 the second microchannel defines a passageway between the first surface and the second surface; and 
 the at least third microchannel defines a passageway between the third surface and the fourth surface, wherein the first microchannel has a cross-sectional area different from at least the second microchannel or the third microchannel. 
   
     
     
         11 . The apparatus of  claim 10 , wherein at least one microchannel has at least one internal dimension of width or height of about 2 mm or less. 
     
     
         12 . The apparatus of  claim 11 , wherein at least one microchannel has at least one internal dimension of width or height of about 0.1 mm or less. 
     
     
         13 . A process, comprising:
 (a) flowing a first stream, having a first temperature, through the first microchannel of the apparatus of  claim 1 ;   (b) flowing a second stream, having a second temperature, through the second microchannel of the apparatus of  claim 1 ; and   (c) flowing a third stream, having a third temperature, through the at least third microchannel of the apparatus of  claim 1 .   
     
     
         14 . The process of  claim 13 , wherein the first stream is flowing at a Reynolds number of about 4,000 or less. 
     
     
         15 . The process of  claim 13 , wherein the residence time of the first stream is about 500 ms or less. 
     
     
         16 . The process of  claim 13 , wherein the first stream is a gaseous fluid and flows through the first microchannel at a pressure drop of about 15 psi or less. 
     
     
         17 . The process of  claim 13 , further comprising:
 (a) placing the first stream in thermal communication with the second stream and the at least third stream.   
     
     
         18 . The process of  claim 17 , wherein when the first stream is a gaseous fluid, and flows through the first microchannel at a pressure drop of about 15 psi or less. 
     
     
         19 . The process of  claim 18 , wherein the residence time of the first gaseous fluid stream is about 500 ms or less. 
     
     
         20 . The process of  claim 17 , wherein the IPHTAP of at least one microchannel is about 30 or greater. 
     
     
         21 . A process, comprising:
 (a) flowing a first fluid through a plurality of first microchannels;   (b) flowing a second fluid through a plurality of second microchannels; and   (c) flowing at least a third fluid through a plurality of at least third microchannels, the plurality of at least third microchannels being in thermal communication with the plurality of first microchannels and with the plurality of second microchannels.   
     
     
         22 . The process of  claim 21 , wherein the total thermal power density is greater than about 1 W/cc. 
     
     
         23 . An apparatus, comprising:
 a first end and a second end;   a first microchannel;   a second microchannel;   a third microchannel;   a fourth microchannel;   a fifth microchannel;   a sixth microchannel; and   a seventh microchannel, each microchannel defining a passageway between the first end and the second end, wherein each microchannel is in thermal communication with at least one of the other microchannels and the first microchannel has a cross-sectional area different from at least the second microchannel.   
     
     
         24 . The apparatus of  claim 23 , wherein when a first portion of a first gaseous fluid, at a first temperature flows through the first microchannel, a first portion of a second gaseous fluid, at a second temperature flows through the second microchannel, a third gaseous fluid, at a third temperature flows through the third microchannel, a fourth gaseous fluid, at a fourth temperature flows through the fourth microchannel, a fifth gaseous fluid, at a fifth temperature flows through the fifth microchannel, a second portion of the first gaseous fluid, flows through the sixth microchannel, and a second portion of the second gaseous fluid, flows through the seventh microchannel, the total thermal power density of the heat exchanger is at least 1 W/cc. 
     
     
         25 . The apparatus of  claim 23 , wherein the weighted average approach is about 150 deg. C.