Fluid processing device and method
First Claim
1. A heat exchanger comprising:
- a plurality of first microchannels and a plurality of second microchannels for conveying first and second fluids respectively;
wherein the first microchannels are in thermal contact with the second microchannels over a microchannel flow length of at least a first value;
wherein the second microchannels are in thermal contact with the first microchannels over a microchannel flow length not greater than a second value;
wherein the first value is at least about 4 times the second value.
1 Assignment
0 Petitions
Accused Products
Abstract
A fluid processing unit having first and second interleaved flow paths in a cross flow configuration is disclosed. The first flow paths are substantially longer than the second flow paths such that the pressure drop in the second flow paths can be maintained at a relatively low level and temperature variations across the second flow paths are reduced. One or more of the flow paths can be microchannels. When used as a vaporizer and/or superheater, the longer first flow paths include an upstream liquid flow portion and a downstream vapor flow portion of enlarged cross sectional area. A substantial pressure drop is maintained through the upstream liquid flow portion for which one or more tortuous flow channels can be utilized. The unit is a thin panel, having a width substantially less its length or height, and is manufactured together with other thin units in a bonded stack of thin metal sheets. The individual units are then separated from the stack after bonding.
60 Citations
61 Claims
-
1. A heat exchanger comprising:
a plurality of first microchannels and a plurality of second microchannels for conveying first and second fluids respectively;
wherein the first microchannels are in thermal contact with the second microchannels over a microchannel flow length of at least a first value;
wherein the second microchannels are in thermal contact with the first microchannels over a microchannel flow length not greater than a second value;
wherein the first value is at least about 4 times the second value. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 51, 52, 53, 54)
-
9. The heat exchanger of 8 wherein the first plurality of microchannels define a flow path between the holes and the second plurality of microchannels define a flow path separate from the holes and in a direction generally orthogonal to a line connecting the holes.
-
10. A vaporizer comprising:
a plurality of generally parallel first vaporization flow paths for conveying a vaporizing fluid interleaved and in thermal contact with a plurality of second generally parallel flow paths for conveying a heat exchange fluid;
wherein each of the first vaporization flow paths include a liquid flow portion in fluid communication with a vapor flow portion having a cross sectional area substantially greater than the cross sectional area of the liquid flow portion; and
wherein the liquid flow portion of each of the first vaporization flow paths include at least one tortuous microchannel having at least three turns of at least about 60 degrees for establishing a substantial pressure drop through the respective liquid flow portions. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21)
-
22. A vaporizer comprising:
a stack of thin sheets integrally bonded, the stack including alternating recessed sheets having holes at opposing ends wherein the recesses in the sheets define at least a portion of first and second distinct flow paths;
wherein the first flow paths are operable to convey a vaporizing fluid between the holes and include a liquid flow portion in communication with a vapor flow portion having a cross sectional area substantially greater than the cross sectional area of the liquid flow portion, the liquid flow portion including at least one tortuous microchannel;
wherein the second flow paths are separate from the holes and in thermal contact with at least a portion of the vapor flow portion of the first flow paths. - View Dependent Claims (23, 24, 25)
-
26. A method comprising:
-
providing a single pass cross-flow heat exchanger comprising interleaved first and second flow paths wherein at least one of the first and second flow paths include at least one microchannel;
conveying a first fluid in the first flow paths;
conveying a combustion gas in the second flow path through an active hot gas flow region of the heat exchanger to transfer heat to the first flow path;
wherein the volumetric heat transfer intensity based on the volume of the active hot gas flow region is at least about 30 W/cm3 and the thermal efficiency, defined relative to an infinitely long countercurrent heat exchanger at the respective fluid inlet conditions, is at least about 70%; and
wherein the pressure drop of the combustion gas through the second flow path in inches of water is less than about 10 times the inverse of the pressure of the combustion gas in atmospheres at an inlet to the second flow paths. - View Dependent Claims (27, 28, 29, 30, 31, 32)
-
-
33. A method of vaporizing a liquid comprising:
-
flowing a first stream including liquid through a plurality of first vaporization microchannels each including a liquid flow portion in fluid communication with a vapor flow portion having a cross sectional area substantially greater than the cross sectional area of the liquid flow portion wherein the liquid flow portions each include at least one tortuous microchannel liquid flow path for establishing a pressure drop through the liquid flow portions;
heating the first stream with a second fluid flowing through second flow paths in thermal contact with the vapor flow portions of the first vaporization microchannels to vaporize at least a portion of the first stream in the vapor flow portions; and
while heating the first stream, maintaining the pressure drop through the liquid flow portion of each of the plurality of first vaporization microchannels at least about equal to the pressure drop through the vapor flow portion to control flow of the first stream through the plurality of first vaporization microchannels. - View Dependent Claims (34, 35, 36, 37)
-
-
38. A method of vaporizing a liquid comprising:
-
flowing a first stream including liquid through a plurality of first vaporization microchannels each including a liquid flow portion in fluid communication with a vapor flow portion having a cross sectional area substantially greater than the cross sectional area of the liquid flow portion;
heating the first stream with a second fluid flowing through second heat exchange microchannels in thermal contact with the first vaporization microchannels to vaporize at least a portion of the first stream;
wherein the Reynolds number of the flow of the second fluid in the second heat exchange microchannels is less than about 1000 and the pressure drop of the second fluid through the second heat exchange microchannels in inches of water is less than about 10 times the inverse of the pressure of the second fluid in atmospheres at an inlet to the second heat exchange microchannels. - View Dependent Claims (39)
-
-
40. A method comprising:
forming a plurality of individual fluid processing units together and then separating the units after some degree of assembly into individual units;
wherein forming the plurality of individual units together includes forming integral metal-to-metal bonds in a stack of thin metal sheets, the stack including alternating recessed sheets wherein the recesses in the sheets define at least a portion of flow paths for the individual fluid processing units, and wherein the width of the individual units after the separation is substantially less than the height of the stack of thin metal sheets. - View Dependent Claims (41, 42, 43, 44, 45, 46)
-
47. A method for vaporizing a liquid to produce superheated vapor:
-
flowing a first stream including liquid through a plurality of first vaporization microchannels disposed between a macrochannel inlet and a macrochannel outlet, each vaporization microchannel including a liquid flow portion in fluid communication with a vapor flow portion having a cross sectional area substantially greater than the cross sectional area of the liquid flow portion;
vaporizing and substantially superheating the first stream in the first vaporization microchannels by heating the first stream with a second fluid flowing through second heat exchange microchannels in thermal contact with the first vaporization microchannels along the microchannel flow length of the first vaporization microchannels. - View Dependent Claims (48, 49, 50)
-
-
55. A method comprising:
-
providing a stack of thin sheets integrally bonded, the stack including a plurality of recessed sheets having holes at opposing ends wherein the recesses in the sheets define at least a portion of a plurality of generally parallel first vaporization flow paths operable to convey a vaporizing fluid between the holes and including a liquid flow portion in communication with a vapor flow portion having a cross sectional area substantially greater than the cross sectional area of the liquid flow portion, the liquid flow portions of each of the first vaporization flow paths including at least one tortuous microchannel for establishing a pressure drop through the liquid flow portion of the first vaporization flow paths;
flowing a first fluid containing liquid into each of the first vaporization flow paths while maintaining a sufficient pressure drop in the liquid flow portions to control distribution of the first fluid to each of the first vaporization flow paths;
while flowing the first fluid, heating the first fluid to vaporize at least a portion of the liquid while in the vapor flow portions. - View Dependent Claims (56, 57)
-
-
58. A fluid processing device comprising:
-
a plurality of first reaction flow paths having a smallest dimension less than about 1 cm and including a reaction catalyst; and
a plurality of second heat exchange microchannels interleaved and in thermal contact with ones of the first reaction flow paths;
wherein the first flow paths are in thermal contact with the second microchannels over a flow length of at least a first value;
wherein the second microchannels are in thermal contact with the first flow paths over a microchannel flow length not greater than a second value;
wherein the first value is at least about 8 times the second value.
-
-
59. A method for forming a heat exchanger system comprising:
-
forming a stacked array of thin sheets forming a portion of a fluid processing system, the stacked array defining a first and second face having a plurality of distinct gas microchannels therebetween; and
connecting the stacked array to a separately formed gas header for distribution of a gas to the plurality of distinct gas microchannels in the stacked array;
wherein each of the first and second faces has a length and a width substantially greater than the distance between the faces. - View Dependent Claims (60, 61)
-
Specification