HK1106743B

HK1106743B - Vapor-compression evaporation system and method

Info

Publication number: HK1106743B
Application number: HK07112384.2A
Authority: HK
Inventors: M．T．霍尔兹阿普; G．P．诺伊斯
Original assignee: The Texas A & M University System; Terrabon Adve, Llc
Priority date: 2004-02-10
Filing date: 2005-02-10
Publication date: 2009-12-24

Description

Vapor compression evaporation system and method thereof

Technical Field

The present invention relates generally to the field of evaporators and heat exchangers, and more particularly to vapor compression evaporation systems and methods therefor.

Background

Typical steam injectors deliver high pressure steam into the injector at a relatively high rate. Steam is commonly used as the working fluid (motive fluid) because it is readily available, however, the ejector is also designed to work with other gases or vapors. For some applications, water and other liquids are sometimes good working fluids because they condense a large amount of vapor without compressing them. The liquid working fluid may also compress a gas or vapor.

High pressure working steam enters a nozzle and flows into a negative pressure head as a high velocity, low pressure jet. Nozzles are efficient devices for converting the enthalpy of high pressure steam or other fluid into kinetic energy. The negative pressure head is connected to the system to be evacuated. The high-speed jet flows out of the nozzle and rushes through the negative pressure head.

Gases or vapors from the system to be evacuated enter the suction head where they are entrained by the high velocity working fluid, which accelerates them to a higher velocity and sweeps them into the diffuser. The process in the diffuser is reversed from that in the nozzle. It converts high-speed, low-pressure steam jet into high-pressure, low-speed steam. Thus, in the last stage, the high velocity steam passes through the diffuser and is exhausted at the pressure at the exhaust pipe.

Disclosure of Invention

In accordance with one embodiment of the present invention, a vapor-compression evaporation system includes a plurality of vessels connected in series, each vessel containing a feed having a non-volatile content. A first group of the plurality of vessels includes vapor compression evaporators and a second group of the plurality of vessels includes effect evaporators. A mechanical compressor is connected to the last vessel in the series of vapor-compression evaporators and is operable to receive vapor from the vessel. A turbine is coupled to the mechanical compressor and is operable to drive the compressor. A pump is operable to deliver cooling liquid to the mechanical compressor, and a tank is connected to the mechanical compressor and is operable to separate liquid and vapor received from the mechanical compressor. A plurality of heat exchangers are connected within each vessel, wherein the heat exchanger in a first vessel of the first set is operable to receive vapor from the tank, at least some of the vapor condensing in the heat exchanger. The heat of condensation provides the heat of vaporization to the first vessel in the first set, and at least some of the vapor of the first vessel in the first set is delivered to the heat exchanger in the next vessel in the first set, whereby the condensing, vaporizing and delivering steps continue until the last vessel in the second set is reached.

Embodiments of the present invention provide a number of technical advantages. Embodiments of the invention may include all, some, or none of these advantages. For example, the compressor may be smaller than previous compressors due to the smaller vapor flow through the compressor. The compression ratio can be adjusted so that the compressor operates in its most efficient range. This is particularly important for straight-lobe compressors, which are more efficient at lower compression ratios. Since multiple stages can be employed in the vapor compression evaporator, the compressor can be smaller and the compressor energy efficiency can be improved by employing liquid water injection.

The heat exchanger coating prevents scaling, thereby helping to increase system pressure and temperature. This has the following benefits: (1) the compressor has a simple structure; (2) the compressor can operate in a more efficient area; and (3) many stages can be used in the multi-effect evaporator section. The heat exchanger can be easily removed to replace worn components, and the tank and heat exchanger can be integrated in a single unit. The channels leading to the heat exchanger feed may have a larger flow area to reduce pressure drop, which may increase the efficiency of the system. A tube allows the heat exchanger to operate at elevated pressures, and the sheet metal heat exchanger surfaces are less expensive than the tubular heat exchanger surfaces. Sensible and latent heat exchangers can be integrated into a single low cost system.

Drawings

For a more complete understanding of the present invention, together with other features and advantages thereof, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:

FIGS. 1 through 8 illustrate various embodiments of vapor compression evaporation systems according to various embodiments of the present invention; and

fig. 9 to 48 illustrate various embodiments of heat exchange systems according to various embodiments of the present invention.

Detailed Description

In certain embodiments, the techniques described herein may be utilized in conjunction with U.S. patent provisional applications 10/944,071, 10/944,374, and 10/944,317, which are incorporated herein by reference.

Fig. 1 through 8 illustrate various embodiments of vapor compression evaporation systems according to various embodiments of the present invention.

FIG. 1 illustrates a vapor-compression evaporation system 10 according to one embodiment of the present invention. In the illustrated embodiment, the system 10 includes a plurality of vessels 12a-f in series to form a multiple effect evaporator system. The multi-effect evaporator system operates at successively lower pressures and temperatures. In general, steam from a higher pressure evaporator boils water in an adjacent lower pressure evaporator. In the illustrated embodiment, the containers 12a-f are divided into two groups. The right set of vessels 12a-c is referred to as a "vapor compression evaporator" and the left set of vessels 12d-f is referred to as a "multi-effect evaporator". The compressed vapor is used to supply energy to the vapor compression evaporator, and excess vapor produced in the vapor compression evaporator is used to supply energy to the multi-effect evaporator. A pump may be required to deliver fluid from a low pressure to a high pressure. For energy recovery, a suitable turbine may be selected for use when the fluid flows from high pressure to low pressure.

Each vessel contains a feed 14 containing non-volatile components such as salt or sugar. It may first be degassed by applying a vacuum (the apparatus of which is not explicitly shown) to the feed 404; however, many other suitable techniques may be employed to effect degassing. For example, feed 14 may be introduced into a packed column operating under vacuum conditions. To enhance degassing, steam may be introduced to entrain dissolved air. Another method of degassing may be to use a membrane that is not hydrophilic, so that a vacuum on one side of the membrane can carry dissolved gases away and liquid cannot pass through.

A mechanical compressor 16 is connected to the last vessel (12c) of the series of vapor-compression evaporators and is operable to receive vapor therefrom. Any suitable mechanical compressor may be used. In the illustrated embodiment, a "combined cycle" engine including a gas turbine 18 (Brayton cycle) and a steam turbine 20 (Rankine cycle) is employed to supply power to the mechanical compressor 16. Waste heat from the gas turbine 18, indicated by reference numeral 19, is utilized to generate steam that powers the steam turbine 20.

The mechanical compressor 16 draws vapor from a low pressure evaporator (12c) of the vapor compression evaporator section. Liquid water (indicated by reference numeral 21) is injected into the mechanical compressor 16 by a suitable pump 22 to keep it cool, which improves energy efficiency. The liquid water may be brine or fresh water. Brine is preferred if the mechanical compressor 16 can withstand salt, otherwise fresh water can be used. If brine is used as the injection water, the separation tank 24 is connected to the mechanical compressor 16 to prevent brine from being entrained in the inlet and outlet vapors. The steam generated by the evaporation of the sprayed water provides energy to the containers 12 a-f.

A plurality of heat exchangers are coupled within each vessel 12 a-f. The heat exchanger 12a is operable to receive vapor from the separation tank 24. At least some of the steam condenses therein, whereby the heat of condensation provides the heat of vaporization to the vessel 12 a. At least some of the vapor in vessel 12a is delivered to heat exchanger 26b, whereby the condensing, evaporating and delivering steps continue until the last vessel in the series (vessel 12f in this embodiment) is reached.

Concentrated product 30 may be removed from each of the containers 12 a-f. Energy added to the system 10 may be removed using a suitable condenser 32. Alternatively, if condenser 32 is eliminated, the energy added to system 10 raises the temperature of concentrated product 30. This is acceptable if the product is not temperature sensitive. Even though the feed 14 is degassed, some gas may enter the system 10. To remove non-condensable components from the system 10, a small gas stream (shown at 27) is withdrawn from each vessel 12a-f, passed through a suitable condenser 28, and sent to a vacuum pump (not shown). The condenser 28 separates water from the withdrawn gas stream, which avoids water vapor loss and reduces the load on the vacuum pump required for the low pressure section of the vessels 12 a-f. Low pressure steam (indicated by reference numeral 29) from the exhaust of steam turbine 20 may be added to the portion of vessels 12a-f where the exhaust steam pressure and evaporator pressure most closely match, in this embodiment between vessels 12c and 12 d. A plurality of sensitive heat exchangers 34 may be connected to vessels 12a-f for heating feed 14 or other suitable functions.

Fig. 2 shows a vapor-compression evaporation system 40 according to another embodiment of the invention. The system 40 is similar to the system 10 above, however, in the system 40 the gas turbine 42 and the steam turbine 44 each drive their own mechanical compressors 46a, 46 b. The compressors 6a, 46b are arranged in series such that the mechanical compressor 46a is connected to and operable to receive vapor from the last vessel (vessel 48c) in the vapor compression evaporator series, while the mechanical compressor 46b receives compressed vapor from the mechanical compressor 46a and delivers it to the separation tank 49.

Fig. 3 shows a vapor-compression evaporation system 60 according to another embodiment of the invention. The system 60 is similar to the system 40 above, however, in the system 60 the mechanical compressors 62a, 62b are connected in parallel such that the mechanical compressors 62a, 62b are each connected to the last vessel in the vapor compression evaporator series (vessel 64c) and are operable to receive vapor from the vessel prior to delivery to the separation tank 66.

Fig. 4 shows a vapor-compression evaporation system 80 according to another embodiment of the invention. System 80 is similar to system 40 above, however, in system 80, liquid water is not directly injected into mechanical compressor 82a or 82 b. Instead, an intercooler using the packed tower 86 is used, and liquid water such as brine or fresh water is dropped from above the packed tower 86. A demister 88 near the top of the intercooler 84 prevents liquid droplets from entering the second compression stage, i.e., the mechanical compressor 82 b. The system 80 also eliminates the separate tank. In this embodiment, the vapor leaving the mechanical compressor 82b enters a heat exchanger 90a in a vessel 92 a.

Fig. 5 shows a vapor-compression evaporation system 100 according to another embodiment of the present invention. The system 100 is similar to the system 10 above, however, the system 100 employs an internal combustion engine 102, such as a diesel or otto-cycle engine, to supply power to a mechanical compressor 104. There are two sources of waste heat from the engine 102: gaseous exhaust gas (indicated by reference numeral 105) and refrigerant circulating through the cylinder. In one embodiment, the circulating refrigerant provides waste heat at about 100 ℃, which can be added to the multi-effect evaporator. The off-gas (105) is about 800 deg.c and can be used to generate additional water vapor for the multi-effect evaporator (vessels 106e, 106f in this embodiment). Since the gas is hot, it may damage the heat exchangers 108e, 108 f. Alternatively, the exhaust 105 may be sent to a packed column 108 with water drops 109, which may be used to reduce the temperature by generating steam. Another advantage of packed tower 108 is that it can clean soot from exhaust gas 105 that may coat the surfaces of heat exchangers 106e, 106f and reduce heat transfer efficiency.

Fig. 6 shows a vapor-compression evaporation system 120 according to another embodiment of the present invention. The system 120 is similar to the system 100 above, however, the system 120 employs one or more thin film evaporators 122a-c in place of some or all of the multi-effect evaporators. In the illustrated embodiment, the thin film evaporators 122a-c each have three chambers. A pair of outer chambers 124a-c, 126a-c are separated by an inner chamber 128 a-c. The saline flows through the outer chambers 124a-c, 126a-c and the fresh water flows through the inner chambers 128 a-c. The outer chambers 126a-c are separated from the inner chambers 128a-c by impermeable membranes 130a-c, while the outer chambers 124a-c are separated from the inner chambers 128a-c by non-hydrophilic, gas permeable membranes 132 a-c.

During operation of one embodiment of the system 120, the inlet water 134 enters the outer chambers 126 a-c. As the incoming water 134 flows through the outer chambers 126a-c, the temperature of the incoming water 134 rises due to heat transfer through the impermeable membranes 130 a-c. The incoming water 134 flows out of the outer chambers 126a-c and into the respective heat exchangers 136a-c where the temperature of the incoming water 134 rises by a few degrees (typically between 5 and 10 c). The heat required by the heat exchangers 136a-c may come from any suitable source. In the illustrated embodiment, the heat exchanger 136c receives heat from the last vessel in the series of vapor compression evaporators (vessel 143 c). The heat exchangers 136a and 136b receive heat from the engine 142.

The incoming water then enters the outer chambers 124 a-c. Water evaporates from the hot incoming water 134 and flows through the non-hydrophilic gas permeable membranes 132a-c, thereby condensing in the internal chambers 128 a-c. The water may then be collected as product water, as indicated by reference numeral 138.

Fig. 7 shows a vapor-compression evaporation system 150 according to another embodiment of the invention. The system 150 is similar to the system 120 above, however, the system 150 utilizes waste heat from the gaseous exhaust 152 of the engine 154 to generate steam 156 employed in the vapor-compression evaporators 158 a-c.

The above system may use any suitable mechanical compressor type, for example, a high speed shaft from a gas or steam turbine is best suited to drive a centrifugal or axial vane compressor. Low speed shafts from diesel or otto engines are best suited to drive cycloid, screw, vane or straight tab compressors (such as roots blowers). Straight tab compressors may be particularly attractive because they are quite inexpensive, yet straight tab compressors are only efficient at low compression rates.

Fig. 8 shows the energy mass balance of the vaporization system 170. The basis of the calculation is T₁The next 1kg of saturated steam. The work required by the compressor 172 is:

the work of the compressor can be divided into two parts: ideal work and "lost" work converted to heat.

W＝W_ideal+W_lost (2)

The following is the entropy calculated around the compressor 172:

accumulation-input-output + generation-consumption (4)

At steady state

Wherein T is_aveIs the average temperature of the compressor 172 and must be expressed in absolute temperature. Replacing T by equation 3_lostReplacing T by arithmetic mean_ave：

The following definitions are obtained:

this definition can be substituted into equation 6:

to solve for x, the spray water that evaporates in the compressor 172, equation 8 can be expanded as follows:

from equation 7, the definition of k can be substituted into equation 9:

water m produced by the vapor compression evaporator 174_vComprises the following steps:

m_v＝n_v(1+x) (11)

wherein n is_vIs the number of stages in the vapor compression evaporator 174, which can be arbitrarily selected.

Water m produced in the multi-effect evaporator section 176_mThe method comprises the following steps:

whereinIs the temperature difference in each heat exchanger of the multi-effect evaporator 176,is the latent heat of vaporization at the inlet of the compressor, andis the average latent heat of the multi-effect evaporator 176.

Water m produced in multi-effect evaporator 176 using waste heat from engine_eThe method comprises the following steps:

it is assumed that waste heat can be utilized as sensible heat (e.g., exhaust gas from a diesel engine, hot gas from a rankine boiler). The factor 2 in equation (13) illustrates the waste heat Q_cCan be used as a displayHeat rather than latent heat. Each evaporator conducting 1/n directly from the exhaust gas stream_eQ_cThe amount of heat of (a). This effectively reduces the output of the multi-effect evaporator by half.

The total amount of water generated is

m_t＝m_v+m_m+m_e (14)

The high temperature heat supplied to the engine 178 is:

the unit heat requirement is:

the requirements for unit work are:

the unit compressor inlet volume is:

the number of equivalent effects is:

table 1 shows the results of a high efficiency engine (η) such as a combined cycle (e.g., Brayton + Rankine cycle) or an efficient regenerative Brayton cycle_e0.6) desired energy efficiency of the driven desalination system. Table 2 shows the results of a medium efficiency engine (η) such as a large diesel engine_e0.4) desired energy efficiency of the driven desalination system. Let the delta T through the heat exchanger of each evaporator be 6 ℃. Table 3 shows the relevant properties of water.

TABLE 3 Heat energy of saturated water per 6 ℃ interval

In both tables 1 and 2, energy efficiency is improved at the higher T1. This can be explained as follows:

a. at a higher temperature T₁To achieve a given temperature difference across the vapor compression evaporator, the compression ratio is reduced. This factor reflects the potential thermal energy of the water.

b. At higher T₁It is possible to have more stages in a multiple effect evaporator.

Another benefit of operating at a higher temperature is that the pressure also increases, which increases the density of the vapor entering the compressor. This allows the compressor to be smaller and more economical. The compressor size can be further reduced by increasing the number of stages in the vapor compression evaporator section. A further benefit of operating at higher temperatures is that the compression ratio is reduced, which allows the use of a straight tab compressor that is energy efficient only at lower compression ratios. Straight tab compressors are particularly desirable because they are less expensive than other types of compressors. Furthermore, their speed and performance characteristics are well matched to diesel engines, which are energy efficient and low cost.

Generally, the desalination heat exchanger is limited to about 120 ℃. Above this temperature, calcium and magnesium carbonates and sulfates precipitate and can foul heat exchanger surfaces. Which would be too low to realize the advantages of a high temperature vapor compression evaporator.

In some embodiments, the non-stick coating may prevent staining of the heat exchanger surface. There are many coating options. Some of which are listed below, although other coatings are also contemplated by the present invention.

a. Teflon coating on metal. The DuPont Silverstone Teflon coating for cookware can withstand temperatures of 290 ℃.

b. The hard anodizing treatment may be performed with aluminum, followed by containing PTFE (polytetrafluoroethylene).

c. Vacuum aluminizing carbon steel followed by hard anodizing and PTFE inclusion.

d. Aluminium, carbon steel or marine brass is impact coated with PPS (vulcanized polypropylene) or PPS/PTFE alloy.

Such a coating may be applied to the side of the heat exchanger exposed to the hot brine. In one embodiment, the base metal may comprise a brine resistant material, such as brass used in ships or in the sea. With this method, if the coating fails, the heat exchanger can be contaminated, but not perforated or leak.

At lower temperatures (═ 120 ℃), a non-stick surface is not required, however resistance to salt water can be applied by cathodic-arc vapor deposition (cathodic-arc vapor deposition) of titanium on other metals such as aluminum or carbon steel. As an alternative to coating the metal surface, it is possible to bond relatively thin polymer films such as PVDF (polyvinylidene fluoride) or PTFE using a suitable binder and/or thermal compounding.

In certain embodiments where the precipitate sticks to a coated or filmed surface, it is possible to add inert solid particles to the circulating salt solution, which continuously rinse and clean the soiled surface. The inert solid particles can be recovered and recycled back into the incoming salt solution before the salt solution is discharged. Alternatively or additionally, the heat exchanger may be temporarily withdrawn for cleaning the surface with dilute acid or other suitable cleaning agent.

The condensing side of the heat exchanger is less demanding. If the base metal is resistant to steam (e.g., marine brass), no additional coating is required. However, if a less resistant metal such as carbon steel or aluminum is used, the condensation surface needs to be treated as follows:

a. hot dip galvanizing carbon steel.

B. Aluminum conversion anodizing (conversion anodizing).

C. The carbon steel is vacuum aluminized followed by anodizing.

D. Nickel is electrolessly coated on aluminum or carbon steel.

E. Cadmium, nickel or zinc is plated on aluminum or carbon steel.

F. Aluminum or carbon steel is dip coated/spray coated/roll coated with PVDF paint.

All of the above coatings or films for the brine side and the vapor side can be applied by "coil coating". In this method, a large roll of sheet metal is continuously unwound and treated to apply a coating or film. The final product is re-rolled into a metal coil and used for shipping. It is well known that this is an economical method of applying high quality coatings to metal surfaces.

Fig. 9 through 48 illustrate various embodiments of heat exchanger assemblies according to various embodiments of the present invention.

Fig. 9 shows an example of a serrated plate 300a for a plate assembly in a heat exchanger assembly according to an embodiment of the invention. The serrated plate 300a may be used in any suitable heat exchanger, such as the embodiment of the heat exchanger assembly shown in FIGS. 27-48 discussed below and/or any of the heat exchanger assemblies 500 shown in FIGS. 56-57 of the above-referenced U.S. patent provisional application 10/944,374.

The serrated plate 300a includes a plurality of dimples 304 formed in a saw-tooth pattern 302. The sawtooth pattern 302 includes a sawtooth pattern section 303 that is replicated multiple times on the plate 300 a. In the embodiment shown in FIG. 9, the sawtooth pattern section 303 includes a row of recesses 304. To form serrated plate 300a, the serrated pattern segments 303 may be stamped into the blank plate at various locations on plate 300 a. For example, to create serrated plate 300a as shown in FIG. 9, the serrated pattern segments (i.e., rows of dimples) 303 may be stamped into the blank plate at one location, the plate may be advanced or indexed, and then the serrated pattern segments (i.e., rows of dimples) 303 may be stamped into a new location, thereby forming a complete array of dimples 304. Using such a process, a relatively small die can be used to create the dimple 304, which can be cost effective.

FIG. 10 illustrates a metal stamping process to form a serrated plate 300a according to one embodiment of the invention. The metal stamping assembly 310 includes a male die 312 having one or more protrusions 314 and a female die 316 having one or more apertures 318 configured to receive the protrusions 314. At step (a), a blank plate 320 is positioned between the male die 312 and the female die 316. At step (b), the male die 312 and the female die 316 are brought together such that the protrusions 314 form the recesses 304 in the blank plate 320. At step (c), the male die 312 and female die 316 are separated, with the metal sheet once again being located between the male die 312 and female die 316. This process may be repeated to form a complete array of dimples 304 in the serrated plate 300 a.

FIG. 11 illustrates a hydroforming process to form a serrated plate 300a according to one embodiment of the present invention. The hydroforming assembly 330 includes a male die 332 configured to receive a fluid 334 and a female die 336 having one or more apertures 338 configured to receive the fluid 334. At step (a), a sheet of metal blank 320 is positioned between a male die 332 and a female die 336. At step (b), the male die 332 and the female die 336 are brought together, and high pressure fluid 334 is introduced into the male die 332 to partially deform the blank plate 320 into the holes 336 in the female die 336, thereby forming the dimples 304 in the blank plate 320. At step (c), the male die 332 and the female die 336 are separated so that the metal plate can be positioned between the male die 332 and the female die 336 again. This process may be repeated to form a complete array of dimples 304 in the serrated plate 300 a.

Fig. 12 shows an example of a serrated plate 300b for a plate assembly of a heat exchanger assembly according to another embodiment of the invention. The serration plate 300b includes: a first plurality of serrated ridges 340 extending in a first direction 342; and a second plurality of serrated ridges 344 extending in a second direction substantially perpendicular to the first direction 342. FIG. 12 also shows a cross-sectional view of serrated plate 300B taken along lines A-A and B-B. The serrated ridges 340 and 344 prevent (or at least reduce the likelihood of) the plate 300b from bending, thereby increasing the durability of the plate 300b and making it easier to manipulate the plate 300 b.

FIG. 13 illustrates a roller assembly 350 forming a ridge in a metal plate 320, such as the ridge 340 or 344 in a serrated plate 300b, according to another embodiment of the invention. A male roller 352 and a female roller 354. The sheet of metal blank 320 may be placed between the male and female rollers 352, 354, and after (or while) the male and female rollers 352, 354 are brought into relative proximity with each other to form a series of ridges in the sheet of metal 320, such as the series of ridges 340 in the serrated plate 300b, one or both of the rollers may be rotated as indicated by arrows 356 and 358.

Fig. 14 shows a cross-section of a plate assembly 360 according to the present invention comprising spacers 362 between adjacent plates 364. Such a configuration may be used in any suitable heat exchanger assembly, such as the heat exchanger assembly 500 shown in fig. 27-48 discussed below and/or any one of the embodiments of the heat exchanger assembly 500 shown in fig. 56-57 of the above-referenced U.S. patent provisional application 10/944,374.

The plate assembly 360 includes a plurality of plates 364 disposed generally parallel to one another and defining a plurality of relatively low pressure channels 366 extending in a first direction alternating with a plurality of relatively high pressure channels 368 extending in a second direction perpendicular to the first direction, such as described above with reference to first and second channels 582 and 586 shown in fig. 57A of U.S. patent provisional application 10/944,374. In the exemplary embodiment, high-pressure passage 368 extends in a first direction, generally indicated by arrow 370, and low-pressure passage 366 extends in a second direction, generally into/out of the page. The plate 364 may include serrations (such as dimples, ridges, or other protrusions) 366, as discussed above. The serrated portions 366 may contact each other in the low pressure passage 366, thereby ensuring that the low pressure passage remains open when high pressure is applied in the high pressure passage 368.

The spacers 362 are positioned between adjacent plates 364 and operate to provide the desired spacing between the plates 364. In certain embodiments, the spacer 362 includes a groove 371 filled with a sealing body 372, which may include any suitable material and/or device suitable for providing a fluid seal. For example, the sealing body 372 may include an elastomeric O-ring or other suitable gasket material. In this embodiment, the spacer 362 has an i-beam shaped cross-section. However, other suitable cross-sections may be employed. The spacers 362 may be formed in any suitable manner, such as by extrusion techniques. Some spacers 362 may be solid, while others may include holes or openings 376 through which fluid may flow. For example, in the particular cross-section shown in FIG. 13, the spacer 362a between two adjacent plates 364 forming the low pressure passage 366 may be solid because fluid flows in a direction into/out of the page, while the spacer 362b between two adjacent plates 364 forming the high pressure passage 368 may include an aperture 376 to allow fluid to flow through such passage 368 generally in the first direction 370.

Fig. 14 also shows a side view of the spacer 362a and the spacer 362b, both shown above the plate assembly 360. As discussed above, the spacer 362a may be solid, while the spacer 362b may include holes to allow fluid flow therethrough. Such apertures 376 may be formed (e.g., by extrusion) after the associated spacers 362b are formed.

Fig. 15 and 16 show the structure of the spacer 362a according to one embodiment of the invention. Fig. 15 shows a top view of the spacer 362 a. The spacer 362a forms a generally rectangular ring that includes four side members 380a and four corner members 382 a. Fig. 16 shows an exploded perspective view of a corner region of the spacer 362a shown in fig. 15. Specifically, fig. 16 shows a corner member 382a, and a first side length member 380a and a second side length member 380 a' connected to the corner member 382 a. The first side length member 380a includes an aperture 376a, while the second side length member 380 a' is solid. Such a configuration may be used to provide fluid flow in the direction generally indicated by arrow 386 a. The corner member 382a includes a groove 388a that may be aligned with the grooves 371a and 371a ' formed in the side members 380a and 380a ', such that the grooves 388, 371a and 371a ' may cooperate to receive a gasket or other sealing body 372.

Fig. 17 and 18 show the structure of a spacer 362b according to another embodiment of the present invention. Fig. 17 shows a top view of the spacer 362 b. The spacer 362b forms a generally rectangular ring that includes four side members 380 b. Fig. 18 shows an exploded perspective view of a corner region of the spacer 362b shown in fig. 17. Specifically, fig. 18 shows how two side members 380b meet to form a corner. Each side member 380 may be cut to 45 deg., thereby forming a 90 deg. angle between adjacent side members 380 b. The first side length member 380b includes an aperture 376b, while the second side length member 380 b' is solid. Also, such a configuration may be used to provide fluid flow in the direction generally indicated by arrow 386 b. The slots 371b and 371b 'formed in the side members 380b and 380 b' may be aligned at the corners and mate with each other to receive a gasket or other sealing body 372.

Fig. 19 and 20 show the structure of a spacer 362c according to another embodiment of the present invention. Fig. 19 shows a top view of the spacer 362 c. The spacer 362c forms a generally rectangular ring that includes four side members 380c and four corner members 382 c. An angle may be cut at the end of each side member 380c and each corner member 382c such that the side members 380c and corner members 382c are connected to form a 90 angle. For example, each end of the side length member 380c and the corner member 382c may be cut at an angle of 22.5 ° to form a 90 ° angle. Fig. 20 shows an exploded perspective view of a corner region of the spacer 362c shown in fig. 19. Specifically, fig. 20 shows a corner member 382c, and a first side length member 380c and a second side length member 380 c' connected to the corner member 382 c. The first side length member 380c includes an aperture 376c, while the second side length member 380 c' is solid. Such a configuration may be used to provide fluid flow in the direction generally indicated by arrow 386 c. The corner member 382c includes a groove 388c that is alignable with grooves 371c and 371c ' formed in the side members 380c and 380c ' such that the grooves 388, 371c and 371c ' cooperate to receive a gasket or other sealing body 372.

Fig. 21 and 22 show the structure of a spacer 362d according to another embodiment of the present invention. Fig. 21 shows a top view of the spacer 362 d. The spacer 362d forms a generally rectangular ring that includes four side members 380d and four corner members 382 d. An angle may be cut at the end of each side member 380d and each corner member 382d such that the side members 380d and corner members 382d are connected to form a 90 angle. For example, each end of side members 380d and corner members 382d may be cut at an angle of 22.5 ° to form a 90 ° angle. Fig. 22 shows an exploded perspective view of a corner region of the spacer 362d shown in fig. 21. Specifically, fig. 22 shows a corner member 382d, and a first side length member 380d and a second side length member 380 d' connected to the corner member 382 d. The first side length member 380d includes an aperture 376d, while the second side length member 380 d' is solid. Such a configuration may be used to provide fluid flow in the direction generally indicated by arrow 386 d. The corner member 382d includes a groove 388d that is alignable with the grooves 371d and 371d ' formed in the side members 380d and 380d ' such that the grooves 388, 371d and 371d ' cooperate to receive a gasket or other sealing body 372. As with the groove 388a shown in FIG. 15, the groove 388d is curved, which is advantageous for receiving the sealing body 372, such as an O-ring or other gasket.

Fig. 23 shows a perspective view of an orthogonal grid plate assembly 400a according to the present invention, which includes a plurality of plates 402 a. The plate assembly 400a may be used in any suitable heat exchanger assembly, such as any of the heat exchanger assemblies 500 shown in fig. 27-48 discussed below and/or the heat exchanger assembly 500 shown in fig. 56-57 of the above-referenced U.S. patent provisional application 10/944,374.

The plate assembly 400a includes a plurality of plates 402a that are positioned substantially parallel to one another and may form a plurality of relatively low pressure channels 404a extending in a first direction that alternate with a plurality of relatively high pressure channels 406a extending in a second direction that is perpendicular to the first direction. In the exemplary embodiment, low-pressure passage 404a extends in a first direction, generally indicated by arrow 408a, and high-pressure passage 406a extends in a second direction, generally indicated by arrow 410 a. Rectangular (e.g., square) conduits 416a are positioned between and connected to the plates 402a, thereby maintaining the channels 404a and 406a between the plates 402 a. Rectangular conduit 416a may be formed of metal or other suitable material and may be rigidly coupled to plate 402a by any suitable method, such as bonding, brazing, or welding.

Fig. 24 shows an exploded view of the orthogonal grid plate assembly 400a of fig. 23. In this embodiment, a rectangular conduit 416a is connected to one side of each plate 402a of the assembly 400 a.

Fig. 25 shows a perspective view of an orthogonal grid plate assembly 400b comprising a plurality of plates 402b, according to another embodiment of the invention. The plate assembly 400b may be used in any suitable heat exchanger assembly, such as any of the heat exchanger assemblies 500 shown in fig. 27-48 discussed below and/or the heat exchanger assembly 500 shown in fig. 56-57 of the above-referenced U.S. patent provisional application 10/944,374.

The plate assembly 400b includes a plurality of plates 402b that are positioned substantially parallel to one another and may form a plurality of relatively low pressure channels 404b extending in a first direction that are alternated with a plurality of relatively high pressure channels 406b extending in a second direction perpendicular to the first direction, such as described above with reference to the first and second channels 404a and 406 a. In the exemplary embodiment, low-pressure passage 404b extends in a first direction, generally indicated by arrow 408b, and high-pressure passage 406b extends in a second direction, generally indicated by arrow 410 b. Rectangular (e.g., square) conduits 416b are positioned between and connected to the plates 402b, thereby maintaining the channels 404b and 406b between the plates 402 b. Rectangular conduit 416b may be formed of metal or other suitable material and may be rigidly coupled to plate 402b by any suitable method, such as bonding, brazing, or welding. In this embodiment, the rectangular conduit 416b is rigidly coupled to the low pressure side of the associated plate 402 b. This allows the rectangular conduit 416b and plate 402b to remain coupled by compressive forces (rather than tensile forces). With such an approach, failure of the coupling does not result in failure of the heat exchanger.

Fig. 26 shows an exploded view of a portion of the orthogonal grid plate assembly 400b of fig. 25. As discussed above, in this embodiment, the rectangular conduit 416b is rigidly coupled to the low pressure side of each plate 402a of the assembly 400 a.

Fig. 27 shows a cross-section of an example of a heat exchanger assembly 500 according to the present invention comprising a housing 510 and a plate assembly 512 located in the housing 510. The housing 510 may comprise any suitable shape and may be formed of any suitable material for containing a pressurized gas and/or liquid. For example, in the embodiment shown in FIG. 27, the housing 510 includes a substantially cylindrical portion 516 and a pair of hemispherical caps 600 (see FIG. 28) attached to opposite ends of the cylindrical portion 516. The cross-section shown in figure 27 is taken at a particular point along the length of cylindrical portion 516, which extends in a direction perpendicular to the plane of the paper.

In general, the heat exchanger assembly 500 is configured such that at least two fluids (e.g., a relatively low pressure fluid and a relatively high pressure fluid) may be communicated into the housing 510 through channels (e.g., relatively low pressure channels and relatively high pressure channels as discussed above with respect to various embodiments) formed by the plurality of plates 513 forming the plate assembly 512, thereby transferring heat between the fluids and out of the housing 510. The housing 510 may include any number of inlets and outlets to allow fluid to flow into and out of the housing 510. In the embodiment shown in fig. 27, the housing 510 includes a first inlet 520, a first outlet 522, a second inlet 524, a second outlet 526, and a third outlet 528. The first inlet 520 and the first outlet 522 are configured such that a first fluid (e.g., a relatively high pressure fluid) 530 may flow into and out of the housing 510. The second inlet 524, the second outlet 526, and the third outlet 528 are configured such that a second fluid (e.g., relatively low pressure) 532 may flow into and out of the housing 510.

Due to heat transfer between the first fluid 530 and the second fluid 532, at least a portion of the first fluid and/or the second fluid may change state within the enclosure 510 and thereby exit the enclosure 510 in a different state than the fluids 530 and/or 532 entering the enclosure 510. For example, in one particular embodiment, relatively high pressure vapor 534 enters housing 510 through first inlet 520, enters one or more first channels in plate assembly 512, is cooled by liquid 514 flowing through one or more second channels in plate assembly 512 adjacent to the one or more first channels, which causes at least a portion of vapor 534 to condense to form vapor condensate 536. Vapor condensate 536 flows to and through first outlet 522. At this point, liquid 540 (e.g., brine, seawater, concentrated fermentation broth, or concentrated brine) enters housing 510 through second inlet 524, enters one or more second channels in plate assembly 512, is heated by steam 534 flowing through one or more first channels adjacent to the one or more second channels in plate assembly 512, which boils at least a portion of liquid 540 to form relatively low pressure steam 542. The low pressure vapor 542 escapes from the housing 510 through the second outlet 526, while the remaining portion of the liquid 540 that is not boiling flows toward and through the third outlet 528.

In some embodiments, the heat exchanger assembly 500 includes one or more pumps 550 operable to pump the liquid 540 exiting the housing 510 through the third outlet 528 back into the housing 510 through the second inlet 524, as indicated by arrow 552. The pump 550 may include any suitable device or devices that pump fluid through one or more fluid channels. As shown in fig. 27, liquid 540 may be supplied to the circuit through feed inlet 554. In embodiments where liquid 540 comprises a solution, such as a seawater solution, a relatively dilute (as compared to the solution exiting housing 510 via third outlet 528) such solution may be supplied via feed inlet 554. In addition, a portion of the liquid 540 drawn toward the second inlet 524 of the housing 510 may be redirected away from the housing 510, as indicated by arrow 556. In embodiments where liquid 540 comprises a solution (e.g., a seawater solution), such redirected liquid 540 may comprise a relatively concentrated form of such solution (as compared to the dilute solution supplied through feed port 554). Although the inlets 520, 524 and outlets 522, 526, and 528 are described herein as single inlets and outlets, each inlet 520, 524 and each inlet 522, 526, and 528 may include virtually any suitable number of inlets or outlets.

In certain embodiments, the first fluid 530 generally comprises a vapor and the second fluid 532 generally comprises a liquid, at least as the first fluid 530 and the second fluid 532 enter the housing 510 via the inlets 520 and 524, respectively. In particular embodiments, second fluid 532 may include brine, seawater, fermentation broth, or brackish water.

The heat exchanger assembly 500 may also include a plurality of mounting devices (or rails) 560 that may be coupled to the housing 510 and operable to mount the plate assembly 512 in the housing 510. Each mounting device 560 may be associated with a particular corner of the plate assembly 512. Each mounting device 560 may be attached to the housing 510 in any suitable manner, such as by welding or using fasteners. In the embodiment shown in fig. 27, a 90Y-shaped cradle is included in which one corner of the plate package 512 is mounted. Each mounting means 560 may extend along the length of the housing 510, or at least along the portion of the length of the housing 510 where the fluids 530 and 532 are in communication, thereby creating separate volumes within the housing 510. The first volume 564 is used to communicate the first fluid 530 through the heat exchanger assembly 500 and includes the first and second chambers 580 and 582, generally to the left and right of the plate assembly 510, and one or more first channels formed by the plate assembly 510. A second volume 566 is provided for communicating the second fluid 532 through the heat exchanger assembly 500, the second volume including third and fourth cavities 584 and 586 generally at the upper and lower edges of the plate assembly 510 and one or more second channels formed by the plate assembly 510.

The first fluid 530 remains separated from the second fluid 532 in the housing 510 due to the configuration of the first volume 564 with the plate assembly 512 and the mounting device 560 and separated from the second volume 566. Additionally, one or more gaskets 562 may be placed between each Y-bracket 560 and its corresponding corner of the plate assembly 512, thereby providing a seal between the first and second volumes 564, 566 at each corner of the plate assembly 512. Gasket 562 may include any suitable type of seal or gasket, may have any suitable shape (e.g., having a square, rectangular, or circular cross-section), and may be made of any material suitable for forming a seal or gasket.

The heat exchanger assembly 500 may also include one or more devices that slide, roll, or otherwise position the plate assembly 512 in the housing 510. Such a device is particularly useful in embodiments where the plate assembly 512 is relatively heavy or massive, such as where the plate assembly 512 is formed of metal. In the embodiment shown in fig. 27, the heat exchanger assembly 500 includes wheels 568 connected to the plate assembly 512 that roll the plate assembly 512 into the housing. The wheels 568 may be aligned and rolled onto a wheel track 570 that is coupled to the housing 510 in any suitable manner.

FIG. 28 illustrates an exemplary side view of the heat exchanger assembly 500 illustrated in FIG. 27, according to one embodiment of the invention. As shown in fig. 28, the plate assembly 512 is located in a housing 510 that includes a substantially cylindrical portion 516 and a pair of hemispherical caps 600 attached to both ends of the cylindrical portion 516. Hemispherical cover 600 may include a flange portion 602 that is connected to a flange portion 604 of cylindrical portion 516 by one or more connection means 606, such as bolts, rivets, or welds. The plate assembly 512 may include a first end plate 612 and a second end plate 614 welded or otherwise rigidly attached to the inner surface of the housing 510, such as indicated by arrow 610.

Fig. 29 and 30 show cross-sections A, B, C, D, E and F taken along lines a-A, B-B, C-C, D-D, E-E and F-F, respectively, shown in fig. 28 according to another embodiment of the invention. In this embodiment, the mounting means (or rails) 560a used to secure the plate assembly 512a in place in the housing 510 include 90 ° Y-shaped brackets into which the corners of the plate assembly 512a are mounted.

As shown in fig. 29, view a shows a hemispherical cap 600 including a flange portion 602. View B shows the first end plate 612 and the cylindrical portion 516 of the housing 510, including the flange portion 604. As discussed above, the first end plate 612 is rigidly attached to the inner surface of the outer shell 510 by welding or other means, as indicated by arrow 610. The first end plate 612 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512 a. Views C and D show baffles 620a and 622a located in high pressure chambers 582 and 580, respectively.

As shown in fig. 30, view E shows the second end plate 614 and the cylindrical portion 516 of the housing 510, including the flange portion 604. As discussed above, the first end plate 612 is rigidly attached to the inner surface of the outer shell 510 by welding or other means, as indicated by arrow 610. Like the first end plate 612, the second end plate 614 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512 a. A push plate 630a may be located in the center of the second endplate 614. The push plate 630a can compress a sealing body 372 (e.g., an O-ring or gasket) located in the spacer 362. Thus, the push plate 630a may have a shape (here, square or rectangular) similar to the cross-sectional shape of the plate 513. The outer perimeter of the push plate 630a may be sealed to the second end plate 614 with an O-ring or other suitable gasket.

As also shown in fig. 30, view F shows a mounting device (or rail) 560a that is attached to the housing 510 and used to secure the plate assembly 512a in place within the housing 510. As discussed above, each mounting rail 560a may be associated with a particular corner of the plate assembly 512 a. Additionally, each mounting rail 560a may be attached to the housing 510 in any suitable manner, such as by welding or using fasteners. As discussed above, each mounting rail 560a includes a 90 ° Y-shaped cradle into which one corner of the plate assembly 512a is mounted. Each mounting means 560a may extend along the length of the cylindrical portion 516 of the housing 510, or at least along a portion of the length of the cylindrical portion 516. One or more gaskets (or other suitable sealing devices) 634a may be positioned alongside each mounting rail 560a to seal the plate assembly 512a from that mounting rail 560 a. In certain embodiments, the gasket 634a may be hollow and may be inflated by a pressurized liquid or gas to ensure a good seal. As shown in fig. 28, a hydraulic mechanism 638 may be used to compress the plates 513 of the plate assembly 512a together. The trapped gas in the elevated chamber 639 acts as a spring to bend the plate assembly 512a with changes in temperature.

FIGS. 31 and 32 show cross-sectional views A, B, C, D, E and F taken along lines A-A, B-B, C-C, D-D, E-E and F-F, respectively, shown in FIG. 28 according to another embodiment of the invention. In this embodiment, the mounting means (or rails) 560b used to secure the plate assembly 512b in place in the housing 510 comprise 45 ° brackets into which the corners of the plate assembly 512b are mounted.

As shown in fig. 31, view a shows a hemispherical cap 600 including a flange portion 602. View B shows the first end plate 612 and the cylindrical portion 516 of the housing 510, including the flange portion 604. As discussed above, the first end plate 612 is rigidly attached to the inner surface of the outer shell 510 by welding or other means, as indicated by arrow 610. The first end plate 612 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512 b. Views C and D show baffles 620b and 622b located in high pressure chambers 582 and 580, respectively. As discussed above, the mounting rail 560b includes a 45 ° bracket into which the corners of the plate assembly 512b are mounted. As such, each corner of the plate assembly 512b may have a portion that is at a 45 ° angle, as with corner 640 b.

As shown in fig. 32, view E shows the second end plate 614 and the cylindrical portion 516 of the housing 510, including the flange portion 604. As discussed above, the first end plate 612 is rigidly attached to the inner surface of the outer shell 510 by welding or other means, as indicated by arrow 610. Like the first end plate 612, the second end plate 614 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512 b. The push plate 630b may be centered on the second end plate 614. The push plate 630b can compress a sealing body 372 (e.g., an O-ring or gasket) located in the spacer 362. Thus, the push plate 630b may have a shape similar to the cross-sectional shape of the plate 513 (here, a square or rectangle with 45 ° corners). The outer perimeter of the push plate 630b may be sealed to the second end plate 614 with an O-ring or other suitable gasket.

As also shown in fig. 32, view F shows a mounting device (or rail) 560b that is attached to the housing 510 and used to secure the plate assembly 512b in place within the housing 510. As discussed above, each mounting rail 560b may be associated with a particular corner of the plate assembly 512 b. Additionally, each mounting rail 560b may be attached to the housing 510 in any suitable manner, such as by welding or using fasteners. Each mounting means 560b may extend along the length of the cylindrical portion 516 of the housing 510, or at least along a portion of the length of the cylindrical portion 516. One or more gaskets (or other suitable sealing devices) 634b may be positioned alongside each mounting rail 560b, thereby sealing the plate assembly 512b from that mounting rail 560 b. In certain embodiments, the gasket 634b may be hollow and may be inflated by a pressurized liquid or gas to ensure a good seal. As shown in fig. 28, a hydraulic mechanism 638 may be used to compress the plates 513 of the plate assembly 512b together. The trapped gas in the lifted chamber 639 acts as a spring to bend the plate assembly 512b with changes in temperature.

FIGS. 33 and 34 illustrate cross-sectional views A, B, C, D, E and F, taken along lines A-A, B-B, C-C, D-D, E-E and F-F, respectively, shown in FIG. 28, according to another embodiment of the invention. In this embodiment, the mounting means (or rails) 560c used to secure the plate assembly 512c in place in the housing 510 comprise circular brackets in which the corners of the plate assembly 512c are mounted.

As shown in fig. 33, view a shows a hemispherical cap 600 including a flange portion 602. View B shows the first end plate 612 and the cylindrical portion 516 of the housing 510, including the flange portion 604. As discussed above, the first end plate 612 is rigidly attached to the inner surface of the outer shell 510 by welding or other means, as indicated by arrow 610. The first end plate 612 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512 c. Views C and D show baffles 620C and 622C located in high pressure chambers 582 and 580, respectively. As discussed above, the mounting rail 560c includes a circular bracket in which the corners of the plate assembly 512c are mounted. As such, each corner of the plate assembly 512c may have rounded corners, as with rounded corners 640 c.

As shown in fig. 34, view E shows the second end plate 614 and the cylindrical portion 516 of the housing 510, including the flange portion 604. As discussed above, the first end plate 612 is rigidly attached to the inner surface of the outer shell 510 by welding or other means, as indicated by arrow 610. Like the first end plate 612, the second end plate 614 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512 c. The push plate 630c may be centered on the second end plate 614. Push plate 630c may compress a sealing body 372 (e.g., an O-ring or gasket) located in spacer 362. Thus, the push plate 630c may have a shape (here, a square or rectangle with rounded corners) similar to the cross-sectional shape of the plate 513. The outer perimeter of the push plate 630c may be sealed to the second end plate 614 with an O-ring or other suitable gasket.

As also shown in fig. 34, view F shows a mounting device (or rail) 560c that is attached to the housing 510 and used to secure the plate assembly 512c in place within the housing 510. As discussed above, each mounting rail 560c may be associated with a particular corner of the plate assembly 512 c. Additionally, each mounting rail 560c may be attached to the housing 510 in any suitable manner, such as by welding or using fasteners. Each mounting means 560c may extend along the length of the cylindrical portion 516 of the housing 510, or at least along a portion of the length of the cylindrical portion 516. One or more gaskets (or other suitable sealing devices) 634c may be positioned alongside each mounting rail 560c to seal the plate assembly 512c from that mounting rail 560 c. In certain embodiments, the gasket 634c may be hollow and may be inflated by a pressurized liquid or gas to ensure a good seal. As shown in fig. 28, a hydraulic mechanism 638 may be used to compress the plates 513 of the plate assembly 512c together. The trapped gas in the lifted chamber 639 acts as a spring to bend the plate assembly 512c with changes in temperature.

FIG. 35 illustrates an exemplary side view of the heat exchanger assembly 500 shown in FIG. 27 in accordance with one embodiment of the present invention. The embodiment shown in fig. 35 is similar to the embodiment shown in fig. 35, except that a screw mechanism 650 is used instead of a hydraulic mechanism 638 to compress the plates 513 of the plate assembly 512 together. Fig. 36 shows a perspective view of a plate assembly 512 according to the present invention, the plate assembly 512 having a first end plate or baffle 612a and a second end plate or baffle 614 a. Endplates 612a and 614a may be operated to seal low pressure chambers 580 and 582 from high pressure chambers 584 and 586.

Fig. 37 shows top and side views of a heat exchanger assembly 500 for transporting latent heat according to one embodiment of the invention. The heat exchanger assembly 500 includes a plurality of plates 513 forming a plurality of high pressure channels 660 alternating with a plurality of low pressure channels 662. The top view illustrates the flow of relatively high pressure fluid through the high pressure channel 660, as indicated by arrows 664. The side view illustrates the flow of relatively low pressure fluid 666 through the low pressure passage 662. As shown in the top view, a number of baffles 668 are located at different locations along the length of the assembly 500 in the high pressure chambers 580 and 582. The baffle 668 may be connected to the inner surface of the housing 510 and/or the outer edge of the plate assembly 512 to block and redirect the flow of high pressure fluid through the high pressure passage 660. As shown in the top view, the area of the high pressure flow gradually decreases as the high pressure fluid moves from the inlet 670 to the outlet 672. This maintains a relatively constant rate of fluid flow through the heat exchanger passage 662 and pushes any non-condensing gases out through the outlet 672. In the case of a smaller heat exchanger assembly 500 with only a few heat exchanger plates 513, a relatively constant velocity through the heat exchanger channels 662 is obtained using spacers of varying width, in particular using relatively wide spacers near the inlet and relatively narrow spacers near the outlet. In this case, the steam velocity through each channel may be relatively constant.

Fig. 38 shows top and side views of a heat exchanger assembly 500 for transporting sensible heat according to another embodiment of the present invention. The heat exchanger assembly 500 includes a plurality of plates 513 forming a plurality of high pressure channels 660 alternating with a plurality of low pressure channels 662. The top view illustrates the flow of the first fluid through the first channel 660, as indicated by arrows 664. The side view illustrates the flow of the second fluid through the second passage 662, as indicated by arrow 665. As shown in the top view, a number of baffles 668 are located at different locations along the length of the assembly 500 in the chambers 580 and 582. As shown in the side view, a number of baffles 668 are located at different locations along the length of the assembly 500 in the chambers 584 and 586. In this embodiment, the baffles 668 are equally spaced, which results in a constant flow rate through the heat exchanger channels 660 and 662.

Fig. 39 shows top and side views of a heat exchanger assembly 500 for transporting latent and sensible heat in a single enclosure 510 according to another embodiment of the present invention. As such, the heat exchanger assembly 500 shown in fig. 39 can be substantially a combination of the heat exchanger assemblies 500 shown in fig. 37 and 38. In this embodiment, the heat exchanger assembly 500 includes: a first portion 700 configured to convey sensible heat; a second portion 702 configured to transport latent heat; and a third portion 704 configured to convey sensible heat. The first and third portions 700 and 704 may have a similar structure to that shown in fig. 38 and discussed above. The second portion 702 may have a structure similar to that shown in fig. 37 and discussed above.

Fig. 40 and 41 illustrate a heat exchanger assembly 500 having a thermosiphon effect according to another embodiment of the present invention. As shown in fig. 40 and 41, the heat exchanger assembly 500 includes a first end plate 612 and a second end plate 614 on opposite ends of a plate assembly 512. Each end plate 612 and 614 includes baffles 668 on both sides of the plate assembly 512 that block high pressure fluid from exiting the ends of the plate assembly 512, as indicated by arrows 710. However, the end plates 612 and 614 do not have baffles at the ends or bottom of the plate assembly 512, thereby allowing the low pressure fluid 712 to flow out of and around the ends of the plate assembly 512, as indicated by arrows 714.

Fig. 42 shows a cross-sectional view of another exemplary heat exchanger assembly 500 according to the present invention, which includes a housing 510 and a plate assembly 512 located in the housing 510. This embodiment may be similar to that shown in fig. 27-28 and discussed above. However, this embodiment would require assembling the plate assembly 512 outside the housing 510 and inserting and mounting the plate assembly 512 in the housing 510.

Because the plate assembly 512 may be relatively large and/or heavy, the plate assembly 512 may be introduced into the housing 510 with one or more insertion mechanisms 730, sliding, rolling, or otherwise placing the plate assembly 512 in the housing 510. In the embodiment shown in fig. 42, such an interposer 730 includes a number of rollers 732 positioned in tracks 734. The plate assembly 512 may be rolled into the cylindrical portion 516 of the housing 510 using a bracket 560 located at and rigidly connected to each corner of the plate assembly 512. Additional guide members 740 may be connected to the housing 510 to guide and align when inserting the plate assembly 512 into the housing 510. A sealant 738 such as silicon or tar may be inserted: (a) between the bracket 560 and each corner of the plate assembly 512; and/or (b) between the support 560 and an interposer 730 and/or other guide member 740 associated with the housing 510. Sealant 738 may eliminate or reduce leakage between high pressure chambers 580, 582 and low pressure chambers 584, 586.

Fig. 43 illustrates a cross-sectional view of yet another exemplary heat exchanger assembly 500 according to the present invention, which includes a housing 510 and a plate assembly 512 located in the housing 510. This embodiment is similar to that shown in fig. 42 and discussed above, except that an expandable gasket 744 is used in place of the sealant 738 between the scaffold 560 and the interposer 730 and/or other guide member 740 associated with the housing 510. Expandable gasket 744 may be a hollow gasket filled with a high pressure gas or liquid, and may be constructed of, for example, an elastomeric material or other malleable metal. In this embodiment, a sealant 738 may also be used to provide a seal between the bracket 560 and each corner of the plate assembly 512.

Fig. 44 shows a perspective view of a plate package 512 assembled for insertion into a housing 510 according to yet another embodiment of the present invention. In this embodiment, the plate assemblies 512 are configured to transfer latent heat as described above with reference to fig. 37. As such, the plate assembly 512 includes baffles 668 adapted to control the path of fluid passing through the plate assembly 512 to transport a fluid that provides latent heat. In this embodiment, the plate assembly 512 further includes a first flange 750 and a second flange 752 located at opposite ends of the plate assembly 512. The first and second flanges 750 and 752 are used to mount the plate assembly 512 to the flanges 602 and 604 of the housing 502, as described below with reference to fig. 46.

Fig. 45 illustrates another perspective view of the assembled plate assembly 512 of fig. 43 showing the location of tensioning rods 760 that seal gaskets 762 located between the angled corner members 764 and the plates 513 of the plate assembly 512. The tension rods 760 may interact with brackets 766 that are rigidly attached to the corner members 764 by methods such as bonding, brazing, or welding.

Fig. 46 shows a side view of an assembled heat exchanger assembly 500 according to an embodiment of the present invention, which includes the plate assembly 512 shown in fig. 44-45. The first flange 750 is an extension of the first end plate 612 of the plate assembly 512. First flange 750 mates with flanges 602 and 604 of housing 510 and is connected between the two flanges by fasteners 606. The second flange 752 is annular and connects the second end plate 614 of the plate assembly 512 to the housing 510. Specifically, second flange 750 is rigidly attached to second end plate 614 and mates with and is attached between flanges 602 and 604 of housing 510 by fasteners 606.

Fig. 47 and 48 illustrate cross-sectional views A, B, C, D, E, F and G, taken along lines a-A, B-B, C-C, D-D, E-E, F-F and G-G, respectively, illustrated in fig. 46, in accordance with one embodiment of the present invention. As shown in fig. 47, view a shows a hemispherical cap 600 including a flange portion 602. View B shows first end plate 612 and first flange 750. As discussed above, the first flange 750 of the end plate 612 mates with and is attached to the flange portion 602 of the cap 600. The first end plate 612 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512. Views C and D show baffles 668a and 668b located in high pressure chambers 582 and 580, respectively.

As shown in fig. 48, view E shows the second end plate 614 and the cylindrical portion 516 of the housing 510, including the flange portion 604. Like the first end plate, the second end plate 614 may include one or more apertures 616 that are operable to equalize pressure across the surface of the plate 513 of the plate assembly 512. The push plate 630 may be centered on the second end plate 614. The push plate 630 may compress a sealing body 372 (e.g., an O-ring or gasket) located in the spacer 362 within the plate assembly, as described above with reference to fig. 28-35. View F shows a second flange 752 that includes a ring that connects the second end plate 614 of the plate assembly 512 with the flange portions 602 and 604 of the housing 510, as shown in fig. 46 and discussed above. The second flange 752 can flex to accommodate dimensional changes caused by thermal expansion. View G shows a mounting device (or rail) 560 that is attached to the housing 510 and used to secure the plate assembly 512 in place within the housing 510. Each mounting rail 560c may be attached to the housing 510 by any suitable method, such as welding or using fasteners. One or more gaskets (or other suitable sealing devices) 634 may be positioned alongside each mounting rail 560 to seal the plate assembly 512 from that mounting rail 560.

Although embodiments of the present invention and their advantages have been described in detail, those skilled in the art may make various modifications, additions, and omissions without departing from the spirit and scope of the invention.

Claims

1. A vapor compression evaporation system comprising:

a plurality of vessels in series, each vessel containing a feed having a non-volatile content, a first group of the plurality of vessels comprising vapor compression evaporators and a second group of the plurality of vessels comprising effect evaporators;

a mechanical compressor connected to the last vessel in the series of vapor-compression evaporators and operable to receive vapor therefrom;

a turbine connected to the mechanical compressor and operable to drive the compressor;

a pump operable to deliver cooling liquid to the mechanical compressor;

a liquid storage tank connected to the mechanical compressor and operable to separate liquid and vapor received from the mechanical compressor;

a plurality of heat exchangers connected within each vessel, the heat exchangers in a first vessel of the first group being operable to receive steam from the tank, at least some of the steam being condensed in the heat exchangers, whereby the heat of condensation provides heat of evaporation to the first vessel of the first group; and

wherein at least some of the vapor of a first vessel in the first set is delivered to the heat exchanger in the next vessel in the first set, whereby the condensing, evaporating and delivering steps continue until the last vessel in the second set is reached.

2. The vapor-compression evaporation system of claim 1, wherein the non-volatile component is selected from the group consisting of salt and sugar.

3. The vapor-compression evaporation system of claim 1, wherein the feed is a degassed feed.

4. The vapor-compression evaporation system of claim 1, wherein the turbine comprises a gas turbine.

5. The vapor-compression evaporation system of claim 1, wherein the turbine comprises a gas turbine and a steam turbine.

6. A vapor-compression evaporation system as set forth in claim 1 further comprising a condenser connected to the last container in the second bank for removing energy from the last container in the second bank.

7. The vapor-compression evaporation system of claim 1, further comprising a plurality of devices connected to each vessel for removing the collected feed from each vessel.

8. A vapor-compression evaporation system as claimed in claim 1, wherein the cooling liquid comprises brine or fresh water.

9. The vapor-compression evaporation system of claim 1, wherein the mechanical compressor comprises first and second mechanical compressors connected in series, the first mechanical compressor being driven by one of a steam turbine and a gas turbine, the second mechanical compressor being driven by the other of the steam turbine and the gas turbine.

10. A vapor-compression evaporation system as set forth in claim 9 further comprising an intercooler connected between the first and second mechanical compressors, the intercooler being operable to receive cooling liquid from the pump.

11. A vapor-compression evaporation system as recited in claim 8, wherein the intercooler includes a de-mister operable to prevent small droplets of liquid from entering the second mechanical compressor.

12. The vapor-compression evaporation system of claim 1, wherein the mechanical compressor comprises first and second mechanical compressors connected in parallel, the first mechanical compressor being driven by one of a steam turbine and a gas turbine, and the second mechanical compressor being driven by the other of the steam turbine and the gas turbine.

13. A vapor compression evaporation system comprising:

an internal combustion engine connected to the mechanical compressor and operable to drive the compressor; (ii) a

A pump operable to deliver cooling liquid to the mechanical compressor;

14. The vapor-compression evaporation system of claim 13, wherein the non-volatile component is selected from the group consisting of salt and sugar.

15. A vapour compression evaporation system according to claim 13, wherein the internal combustion engine comprises a diesel engine or an otto cycle engine.

16. A vapor-compression evaporation system as set forth in claim 13 further comprising a condenser connected to the last container in the second bank for removing energy from the last container in the second bank.

17. The vapor-compression evaporation system of claim 13, further comprising a plurality of devices connected to each vessel for removing the collected feed from each vessel.

18. A vapor-compression evaporation system as claimed in claim 13, wherein the cooling liquid comprises brine or fresh water.

19. The vapor-compression evaporation system of claim 13, further comprising a packed tower associated with the internal combustion engine, the packed tower operable to receive exhaust from the internal combustion engine.

20. A vapor compression evaporation system comprising:

a plurality of vessels in series, each vessel containing a feed having a non-volatile content, a first group of the plurality of vessels comprising vapor compression evaporators and a second group of the plurality of vessels comprising thin film evaporators;

A pump operable to deliver cooling liquid to the mechanical compressor;

a plurality of heat exchangers connected within each vapor compression evaporator, the heat exchangers in the first vessel of the first group being operable to receive vapor from the tank, at least some of the vapor condensing in the heat exchangers, whereby the heat of condensation provides heat of vaporization to the first vessel of the first group; and

21. The vapor-compression evaporation system of claim 20, wherein the non-volatile component is selected from the group consisting of salt and sugar.

22. A vapour compression evaporation system according to claim 20, wherein the internal combustion engine comprises a diesel engine or an otto cycle engine.

23. A vapor-compression evaporation system as set forth in claim 20 further comprising a condenser connected to the last container in the second bank for removing energy from the last container in the second bank.

24. The vapor-compression evaporation system of claim 20, further comprising a plurality of devices connected to each vessel for removing the collected feed from each vessel.

25. A vapor-compression evaporation system as claimed in claim 20, wherein the cooling liquid comprises brine or fresh water.

26. The vapor-compression evaporation system of claim 20, wherein each thin film evaporator comprises an inner chamber and two outer chambers formed by an impermeable film and a non-hydrophilic, gas permeable film.

27. A vapor-compression evaporation system as recited in claim 26, wherein the brine flows through two outer chambers and the fresh water flows through the inner chamber.

28. A vapour compression evaporation system according to claim 26, in which exhaust gas from the internal combustion engine is operable to produce vapour which is fed into the heat exchanger in the first container in the first bank.

29. A method of compressed vapor evaporation comprising:

conveying a feed having non-volatile components into a plurality of vessels in series;

connecting a mechanical compressor to the last vessel in the series;

receiving a vapor from the last vessel in the series by the mechanical compressor;

driving the mechanical compressor with a turbine;

delivering a refrigeration liquid to a mechanical compressor;

separating liquid and vapor received from the mechanical compressor;

receiving the separated vapor by a heat exchanger connected to the first vessel in the series, at least some of the vapor condensing in the heat exchanger, whereby the heat of condensation provides heat of vaporization to the first vessel in the series; and

at least some of the vapor in the first vessel of the series is delivered to a heat exchanger associated with the next vessel of the series, whereby the condensing, evaporating and delivering steps continue until the last vessel of the series is reached.

30. The vapor compression evaporation process of claim 29, further comprising degassing the feed.

31. The vapor compression evaporation method of claim 29, wherein driving the mechanical compressor with the turbine comprises driving the mechanical compressor with a gas turbine.

32. The vapor compression evaporation method of claim 29, wherein driving the mechanical compressor with the turbine includes driving the mechanical compressor with a gas turbine and a steam turbine.

33. The vapor compression evaporation process of claim 28, further comprising removing energy from the last vessel in the series.

34. The vapor compression evaporation process of claim 28, further comprising removing the pooled feed from each vessel.

35. The vapor compression evaporation method of claim 28, wherein the mechanical compressor comprises first and second mechanical compressors connected in series, the method comprising the first mechanical compressor being driven by a turbine and the second mechanical compressor being driven by a gas turbine.

36. The vapor compression evaporation method of claim 28, further comprising connecting an intercooler between the first and second mechanical compressors, the intercooler operable to receive cooling liquid from the pump.

37. The vapor compression evaporation method of claim 28, further comprising preventing liquid droplets from entering the second mechanical compressor.

38. The vapor compression evaporation method of claim 28, wherein the mechanical compressor comprises first and second mechanical compressors connected in parallel, the method further comprising the first mechanical compressor being driven by a turbine and the second mechanical compressor being driven by a gas turbine.