Vapor pressure enhancement (VPE) direct water chilling-heating process and apparatuses for use therein

A Vapor Pressure Enhancement Direct Water Chiller, designated as a VPE chiller, a Vapor Pressure Enhancement Direct Water Heater, designated as a VPE heater, and a dual purpose integrated Vapor Pressure Enhancement Direct Water Chiller/Heater, designated as a VPE chiller/heater are introduced. A VPE-chiller comprises multiple pressure processing zones and is based on absorption vapor pressure enhancement operation. It comprises multitude of processing zones, Z-1, Z-2, . . . , Z-N that are operated under pressure P.sub.1, P.sub.2, . . . , P.sub.N. Each pressure zone (Z-n) contains a water evaporation zone (Z-En), a vapor pressure enhancement zone (Z-VPEn) and a second vapor condensing zone (Z-Xn). There are a set of rotating discs to provide water evaporation surfaces in the evaporation zone; there are flat heat conductive tubes for forming falling films of absorbing solution and falling films of water in the vapor pressure enhancement zone; there are condenser tubes in the condensation zone. A first vapor is absorbed and second vapor is generated in the enhancement zone; the second vapor is condensed in the condensing zone. Outdoor air, cooling water or air/water combination is used to remove the heat of condensation. The construction and operations of a VPE heater is similar to that of a VPE chiller.

BACKGROUND OF THE INVENTION 
1. Field of Invention 
The process and apparatus of the present invention are related to adiabatic 
water chilling and heating operations coupled with absorption vapor 
pressure enhancement operations. 
2. Brief Description of the Prior Art 
A large scale absorption air conditioning process comprises (a) a step of 
producing a stream of chilled liquid such as water or an aqueous solution 
of ethylene glycol at around 7.2.degree. C. (45.degree. F.), in an 
absorption liquid chiller and (b) a step of circulating a stream of the 
chilled liquid through air handlers to remove heat from indoor air and 
thereby return the liquid at around 15.5.degree. C. (60.degree. F.). 
Manufacturers of absorption chillers are Trane Corp. in Wisconsin and 
Carrier Corp. in New York State . There are several manufacturers in Japan 
including Sanyo, Ebara, Mitsubishi and Yasaki. A commercial absorption 
liquid chiller has a large vacuum enclosure enclosing (a) an evaporation 
zone, (b) an absorption zone, (c) a regeneration zone and (d) a 
condensation zone. The processing steps are as follows: 
(a) As water enters the evaporation zone, flash vaporization causes 
formation of a first vapor and a mass of internal chilled water at around 
4.4.degree. C. (40.degree. F). An external chill water at a first 
temperature around 15.5.degree. C. (60.degree. F.) then exchanges heat 
with the internal chill water and is thereby cooled to a second 
temperature at around 7.2.degree. C. (45.degree. F.).The chilled external 
chill water is then circulated to air handlers and heated to the first 
temperature and returned to the liquid chiller; 
(b) The water vapor is drawn to the absorption zone and is absorbed in a 
strong absorbing solution such as 63% aqueous lithium bromide solution. 
The absorbing solution is thereby diluted and becomes a weak absorbing 
solution, say 58% lithium bromide. The heat of absorption is released to a 
cooling water stream; 
(c) The weak absorbing solution then enters the regeneration zone, wherein 
it is heated and vaporized to generate a near ambient pressure water vapor 
and becomes a strong absorbing solution that is heat exchanged and 
returned to the absorbing zone; 
(d) The near ambient pressure water vapor is condensed by rejecting heat to 
a cooling water stream and the condensate formed is heat exchanged and 
returned to the evaporation zone. 
The operations in a small conventional absorption air conditioner are 
similar to those of a larger unit described, except that the internal 
chilled water produced in the evaporation zone is circulated directly to 
an air handler. 
An Immediate Heat Upgrading Absorption Air Conditioning System. (IHUA 
System ) has been introduced by Chen-Yen Cheng and has been described in 
U.S. Pat. No. 5,209,071 and corresponding international applications. The 
system uses Immediate Heat Upgrading Absorption Air Handlers (IHUA air 
handlers). In this system, an absorption solution consisting of a common 
salt and water is circulated through the IHUA air handlers to upgrade heat 
taken from a first air mass or water and release the upgraded heat to a 
second air mass immediately. Production of chilled water is avoided. An 
IHUA air handler has one or more Modular Evaporation-Absorption panels 
(E-A panels) with two sets of heat transfer fin assemblies. An E-A panel 
has two closely spaced heat conductive walls enclosing a film evaporative 
zone and a film absorption zone that respectively exchange heat with air 
to be cooled and air to be heated through the two sets of fin assemblies. 
A multiple pressure zone IHUA air handler and multiple pressure zone 
evaporation and absorption operations have been described. It is noted 
that the present application is a continuation in part application of a 
co-pending U.S. application Ser. No. 08/295,771, which is a continuation 
application of U.S. application Ser. No. 851,298 that has become the U.S. 
Pat. No. 5,209,071 described. 
BRIEF DESCRIPTION OF THE INVENTION 
A Vapor Pressure Enhancement Direct Water Chiller, designated as a VPE 
chiller, a Vapor Pressure Enhancement Direct Water Heater, designated as a 
VPE heater, and a dual purpose integrated Vapor Pressure Enhancement 
Direct Water Chiller/Heater, designated as a VPE chiller/heater are 
introduced. 
An air conditioning system for a building may have one or more evaporators, 
referred to as regenerators, for regenerating absorbing solution. A 
regenerator may concentrate enough absorbing solution to be used in 
several VPE chillers, VPE heaters or VPE chiller/heaters. Then, a VPE 
chiller may supply enough chill water for use in a multitude of air 
handlers for room cooling. Similarly, a VPE heater may supply enough warm 
water for use in a multitude of air handlers for room heating. Of course, 
a VPE chiller/heater can be used for both cooling and heating of a 
building and may be use in combination with several air handlers. Such a 
central air conditioning system may be properly coordinated for good 
economy and convenience. 
A VPE chiller produces a stream of system chill water by flash vaporizing a 
stream of system water under a first low pressure. The water vapor 
generated is referred to as a first vapor and also as an inner water 
vapor. The inner water vapor is absorbed into an absorbing solution at an 
elevated temperature and the heat of absorption is utilized to generate a 
second vapor that is also refer to as an outer water vapor at a second 
pressure that is substantially higher than the first pressure. The outer 
water vapor is condensed by releasing heat of condensation to outdoor air 
or cooling water. Evaporative condensers may be used to condense the outer 
water vapor. The diluted absorbing solution is concentrated by an 
evaporation operation in an absorbing solution regenerator. The 
transformation from the inner water vapor to the outer water vapor is 
referred to as an absorption vapor pressure enhancement operation and also 
simply as a VPE operation. Since the inner vapor and the outer vapor are 
the inlet vapor and outlet vapor for the VPE operation in the VPE 
chillier, they are respectively referred to as the first vapor and second 
vapor of the VPE operation. 
A VPE heater produces a stream of system heated water by condensing an 
inner water vapor to be described into a stream of system water under a 
near adiabatic condition. First of all, heat is taken in from the 
environment, for example, from the outdoor air, lake water and river water 
and some waste heat sources, into the VPE heater to vaporize water under a 
first pressure to thereby generate a low pressure water vapor. The vapor 
generated is referred to as an outer water vapor. The outer water vapor is 
absorbed into an absorbing solution at an elevated temperature and the 
heat of absorption is utilized to generate a water vapor at a second 
pressure that is substantially higher than the first pressure. The vapor 
generated becomes the inner water vapor used to heat the system water. 
The transformation from the outer water vapor to the inner water vapor is 
also an absorption vapor pressure enhancement (VPE) operation. Since the 
outer vapor and the inner vapor are respectively the inlet vapor and 
outlet vapor of the VPE operation, they are respectively referred to as 
the first and the second vapor of the VPE operation. 
Some terminologies that are used in relation to both a VPE chiller and a 
VPE heater are summarized as follows: 
(a) "An adiabatic liquid-vapor interaction" refers both to the flash 
vaporization in a VPE chiller and the adiabatic condensation of the inner 
water vapor into the system water in a VPE heater. 
(b) "Heat interaction with the environment" refers both to removing heat of 
condensation by outdoor air or cooling water in a VPE chiller and 
generation of outer vapor by vaporizing water upon receiving heat from 
outdoor air or any low temperature heat source in a VPE heater. 
(c) "An adiabatic liquid-vapor interaction zone" refers both to the flash 
vaporization zone of a VPE chiller and the adiabatic inner vapor 
condensation zone of a VPE heater. 
(d) "An environmental heat interaction zone" refers both to the second 
vapor condensing zone in a VPE chiller and the outer water vapor 
generation zone in a VPE heater. 
(e) "An inner water vapor" refers both to the vapor formed in flash 
vaporization of the system water in a VPE chiller and the vapor to be 
condensed into the system water in a VPE heater. 
(f) "An outer water vapor" refers both to the second vapor to be condensed 
by heat interaction with the environment in a VPE chiller and the vapor 
produced by heat interaction with the environment in a VPE heater. 
A VPE chiller may be divided into a multitude of pressure zones and 
multiple pressure zone operations may be used to conduct the flash 
vaporization, first vapor (inner vapor) absorption, second vapor (outer 
vapor) generation and second vapor (outer vapor) condensation operations. 
Such a VPE Chiller may be referred to as a Vapor Pressure Enhancement 
Multiple Pressure Zone Direct Water Chiller and also referred to as a 
VPE/MPZ Direct Water Chiller or simply as a VPE/MPZ Chiller. 
A VPE-MPZ chiller comprises multiple processing sub-zones, Z-1 through Z-N. 
Each pressure sub-zone (Z-n) contains a water evaporation zone (Z-En), a 
vapor pressure enhancement zone (Z-VPEn) and a second vapor condensing 
zone (Z-Xn). 
There are one or more sets of rotating discs or other packing device to 
provide water evaporating surfaces in the evaporation zone; there are 
parallel vertical walls or flat tubes made of heat conductive material for 
forming falling absorbing solution films and forming falling water films 
in the vapor pressure enhancement zone; there are condenser tubes in the 
condensation zone to condense the second vapor. In a Type A system, 
outdoor air is used to remove the heat of condensation and heat transfer 
fins are provided on the condenser tubes. In a Type B system, cooling 
water passes inside of the condenser tubes to thereby condense the second 
vapor outside of the tubes. 
The following operational steps take place in each pressure zone: 
(1) Water is vaporized in each evaporation zone to generate a first vapor 
(inner vapor) and chill the water; 
(2) The first vapor (inner vapor) is absorbed and a second vapor (an outer 
vapor) is generated in each vapor pressure enhancement zone; 
(3) The second vapor (outer vapor) is condensed in each condensing zone; 
(4a) In a Type A VPE/MPZ chiller, a stream of outdoor air flows through the 
fins to remove the heat of condensation; 
(4b) In a Type B VPE/MPZ chiller, a stream of cooling water flows through 
the condenser tubes to remove the heat of condensation. 
A VPE heater may also be divided into multiple pressure zones and multiple 
pressure zone operations may be used to conduct the heat interactions with 
the environment, such as outdoor air, and various heat sources, outer 
vapor generation, outer vapor absorption, inner vapor generation and near 
adiabatic inner vapor condensation into the system water. Such a VPE 
heater may be referred to as a Vapor Pressure Enhancement Multiple 
Pressure Zone Direct Water Heater and also referred to as a VPE/MPZ Direct 
Water Heater or simply as a VPE/MPZ heater. The structure of a VPE/MPZ 
heater is very similar to that of a VPE/MPZ chiller. A dual purpose 
VPE/MPZ chiller/heater can be used as a VPE/MPZ chiller and a VPE/MPZ 
heater by simply changing the flows of absorbing solution and water 
streams.

There are one or more sets of rotating discs or other packing devices to 
provide vapor-liquid interaction surfaces in the adiabatic liquid-vapor 
interaction zone (Z-En); there are flat tube or parallel vertical walls 
made of heat conductive material for forming falling absorbing solution 
films and forming falling and evaporating water films in the vapor 
pressure enhancement zone (Z-VPEn); there are heat transfer tubes and heat 
transfer fins in the heat interaction zone (Z-Xn) to generate the outer 
water vapor. 
In operation, the following operational steps take place in each pressure 
zone: 
(1) In each heat interaction zone Z-Xn, heat is received from the outdoor 
air or other low temperature heat sources to generate an outer water vapor 
V.sub.nn ; 
(2) The outer water vapor V.sub.nn is absorbed and an inner water vapor 
V.sub.nn is generated in each vapor pressure enhancement zone (Z-VPEn); 
(3) The inner vapor V.sub.nn is condensed and the system water is heated in 
each adiabatic liquid-vapor interaction zone (Z-En). 
PREFERRED EMBODIMENT OF THE INVENTION 
FIG. 1 illustrates a system for providing air conditioning in a building 
with a multitude of air handlers. It comprises one or more Vapor Pressure 
Enhancement Direct Water Chiller/Heaters 1a, 1b, designated as a VPE 
chiller/heaters. A VPE chiller/heater is a dual purpose unit that can be 
used as a chiller or a heater by simple adjustments of the flows of 
absorbing solutions and water. A VPE chiller produces chill water 
(L.sub.H).sub.12 by flash vaporizing system water under a low pressure and 
a low temperature, respectively referred to as a first pressure and a 
first temperature. The low pressure water vapor generated is referred to 
as first water vapor. Since the first water vapor is generated from the 
system water, it is also referred to as an inner water vapor. The chill 
water (L.sub.H).sub.12 is circulated through one or more air handlers 2a, 
2b, in the rooms to cool the room air. The chill water is heated and 
becomes (L.sub.H).sub.21 and recycled to the chillers. The first water 
vapor is absorbed into an absorbing solution at an elevated temperature 
and the heat of absorption is utilized to generate a second water vapor at 
a second pressure that is higher than the first pressure. The second water 
vapor is condensed by releasing heat of condensation to outside air or 
cooling water. Since the second vapor enters into a heat exchange relation 
with the environment such as with outdoor air or cooling water, it is also 
referred to as an outer water vapor. One may also use evaporative 
condensers in condensing the second vapor streams. In an evaporative 
condenser, water is applied on the condensing surfaces and heat of 
absorption is removed by vaporizing the water on the surface and the water 
vapor generated is carried away by the circulating air. The circulating 
air stream is both heated and humidified. An evaporation condenser may be 
considered as a combination of a condenser and a cooling tower. By using 
an evaporative condenser, the use of a cooling tower is not needed. The 
diluted absorbing solution is concentrated by an evaporation operation in 
an absorbing solution regenerator 3. 
A VPE chiller may be divided into a multitude of pressure zones and 
multiple pressure zone operations may be used to conduct the flash 
vaporization, first vapor absorption, second vapor generation and second 
vapor condensation operations described. Such a VPE chiller may be 
referred to as a Vapor Pressure Enhancement Multiple Pressure Zone Direct 
Water Chiller and also referred as a VPE/MPZ Direct Water Chiller or 
simply as a VPE/MPZ chiller. Operations conducted in a multiple pressure 
zone chiller has many advantages over operations conducted in a single 
pressure zone chiller. These advantages are: 
1. Temperature driving forces are more effectively utilized; 
2. Thermodynamically, the operations are more efficient; 
3. The concentration of the absorbing solution used is considerably lower; 
4. The operating concentration range is much larger; 
5. The coefficient of performance (C.O.P.) value is considerably higher. 
FIG. 2 illustrates the structure and operations of a VPE/MPZ chiller. Five 
Pressure zone unit is illustrated. It comprises five pressure sub-zones, 
designated as Z-1 (3a), Z-2 (3b), Z-3 (3c), Z-4 (3d), and Z-5 (3e). There 
are flash vaporization sub-zone Z-En, a vapor pressure enhancement 
sub-zone Z-VPEn and a second vapor condensation sub-zone Z-Xn in each 
pressure sub-zone. Each vapor pressure enhancement sub-zone, Z-VPEn, 
comprises a first vapor absorption sub-zone Z-Jn and a second vapor 
generation sub-zone Z-Sn. Therefore, there are Z-En, Z-Jn, Z-Sn, Z-Xn 
sub-zones in Z-n pressure sub-zone, where n is 1 through 5. 
In operation, a stream of system water L.sub.01 recycled from air handlers 
is successively flash vaporized in Z-E1 4a, Z-E2 4b, Z-E3 4c, Z-E4 4d, and 
Z-E5 4e under successively lower pressures (P.sub.E).sub.1, 
(P.sub.E).sub.2, (P.sub.E).sub.3, (P.sub.E).sub.4 and (P.sub.E).sub.5. 
First water vapor streams V.sub.11, V.sub.22, V.sub.33, V.sub.44, V.sub.55 
are generated and the water is successively chilled to become L.sub.12, 
L.sub.23, L.sub.34, L.sub.45, L.sub.50. The final system chill water is 
circulated to the air handlers to remove heat from air and be heated and 
recycled back as L.sub.01. 
Since a flash vaporization operation is a near adiabatic operation 
involving a liquid phase and a vapor phase, it is also referred to as "an 
adiabatic liquid-vapor interaction." Similarly, a flash vaporization zone 
is also referred to as "an adiabatic liquid-vapor interaction zone." 
A vapor pressure enhancement operation by absorption and an apparatus to be 
used therein have been described by Chen-Yen Cheng in U.S. Pat. No. 
5,061,306. Such apparatus and operations are used in each vapor pressure 
enhancement sub-zone, designated as a VPEn sub-zone or Z-VPEn. A VPEn 
sub-zone comprises a first vapor absorption sub-zone and a second vapor 
generation sub-zone, respectively designated as Z-Jn sub-zone and Z-Sn 
sub-zone. A VPE sub-zone comprises a multitude of vertical heat conductive 
walls or flat tubes that separate the first vapor absorption sub-zone Z-Jn 
from the second vapor generation sub-zone Z-Sn. A falling film of an 
absorbing solution and a falling film of water are respectively applied on 
the two surfaces of each vertical wall. A stream of first vapor V.sub.nn 
is absorbed into the absorbing solution in Z-Jn sub-zone at a temperature 
higher than the saturation temperature of the first vapor. The absorbing 
solution is thereby diluted to become a weaker absorbing solution. The 
heat of absorption is transmitted through the vertical wall to vaporize 
water in Z-Sn sub-zone, generating a stream of second vapor V.sub.nn. 
In the system illustrated, there are five vapor pressure enhancement 
sub-zones, designated as Z-VPE1 5a, and Z-VPE2 5b, Z-VPE3 5c, Z-VPE4 5d, 
Z-VPE5 5e. There are five first vapor absorption sub-zones, designated as 
Z-J1, Z-J2, Z-J3, Z-J4 and Z-J5 and five second vapor generation 
sub-zones, designated as Z-S1, Z-S2, Z-S3, Z-S4 and Z-S5 in these vapor 
pressure enhancement sub-zones. 
In operation, a strong absorbing solution J.sub.05 from a regenerator is 
introduced into Z-J5 sub-zone as falling film, a water stream L.sub.55 is 
introduced into Z-S5 sub-zone as a falling film and the first vapor 
V.sub.55 is brought in contact with the absorbing solution in Z-J5. The 
absorbing solution absorb the first vapor to become a weaker solution 
J.sub.54 which is introduced in Z-J4 as a falling film. The heat of 
absorption is transmitted through the vertical wall to vaporize the water 
in Z-S5 to generated a second vapor V.sub.55 at a pressure substantially 
higher than the saturation temperature of the first vapor V.sub.55. 
Similar operations are conducted in the other VPE sub-zones, Z-VPE4, 
Z-VPE3, Z-VPE2 and Z-VPE1. The operations conducted in all the VPE 
sub-zones may be summarized as follows: 
1. Absorbing solution J.sub.05 and water L.sub.55 are respectively 
introduced into Z-J5 and Z-S5 to form falling films and first vapor 
V.sub.55 is brought in contact with the absorbing solution in Z-J5. A 
weakened solution J.sub.54 is formed and a second vapor V.sub.55 is 
generated. 
2. Absorbing solution J.sub.54 and water L.sub.44 are respectively 
introduced into Z-J4 and Z-S4 to form falling films and first vapor 
V.sub.44 is brought in contact with the absorbing solution in Z-J4. A 
weakened solution J.sub.43 is formed and a second vapor V.sub.44 is 
generated. 
3. Absorbing solution J.sub.43 and water L.sub.33 are respectively 
introduced into Z-J3 and Z-S3 to form falling films and first vapor 
V.sub.33 is brought in contact with the absorbing solution in Z-J3. A 
weakened solution J.sub.32 is formed and a second vapor V.sub.33 is 
generated. 
4. Absorbing solution J.sub.32 and water L.sub.22 are respectively 
introduced into Z-J2 and Z-S2 to form falling films and first vapor 
V.sub.22 is brought in contact with the absorbing solution in Z-J2. A 
weakened solution J.sub.21 is formed and a second vapor V.sub.22 is 
generated. 
5. Absorbing solution J.sub.21 and water L.sub.11 are respectively 
introduced into Z-J 1 and Z-S1 to form falling films and first vapor 
V.sub.11 is brought in contact with the absorbing solution in Z-J1. A 
weakened solution J.sub.10 is formed and a second vapor V.sub.11 is 
generated. 
There are condensing sub-zone Z-X1 6a, Z-X2 6b, Z-X3 6c, Z-X4 6d and Z-X5 
6e for condensing the second vapor streams V.sub.11, V.sub.22, V.sub.33, 
V.sub.44, V.sub.55 respectively. Outdoor air or cooling water may be used 
to remove the heat of condensation. It shows that outdoor air G.sub.01 
flow successively through the sub-zones to condense the second vapors 
V.sub.11, V.sub.22, V.sub.33, V.sub.44 and V.sub.55 and thereby from 
condensate streams L.sub.11, L.sub.22, L.sub.33, L.sub.44 and L.sub.55 
which are respectively recycled to Z-S1, Z-S2, Z-S3, Z-S4 and Z-S5 
sub-zones. The air G.sub.01 is heated successively to become G.sub.12, 
G.sub.23, G.sub.34, G.sub.45 and G.sub.50. When outside air is used to 
provide the cooling, it is desirable to use heat transfer fins to enhance 
heat transfer. 
One may use a cooling water stream (L.sub.c).sub.01 instead of the outdoor 
air G.sub.01. The cooling water is successively heated by removing the 
heat of condensation of the second vapor streams and becomes 
(L.sub.c).sub.12, (L.sub.c).sub.23, (L.sub.c).sub.34, (L.sub.c).sub.45 and 
(L.sub.c).sub.50 The heated water (L.sub.c).sub.50 is processed in a 
cooling tower to be cooled and returned as (L.sub.c).sub.01. As has been 
described, one may also use evaporative condensers in condensing the 
second vapor streams. 
Since each of these second vapor condensation zone has a heat interaction 
with the environment, such as with outdoor air or cooling water, it is 
also referred to as "an environmental heat interaction zone" or simply as 
"a heat interaction zone." 
FIGS. 3 and 4 respectively illustrate a vertical cross-section. Section 
A--A , and a horizontal cross-section , Section B--B of a Type A VPE-MPZ 
Direct Water Chiller. Referring to these Figures, a Type A VPE-MPZ chiller 
comprises a vacuum enclosure 7 and multiple pressure processing sub-zones. 
In the figure, five processing sub-zones Z-1 (7a), Z-2 (7b), Z-3 (7c), Z-4 
(7d) and Z-5 (7e) are illustrated. Each pressure sub-zone (Z-n) contains a 
water evaporation zone (Z-En) 8, a vapor pressure enhancing zone (Z-VPEn) 
9, and a second vapor condensing zone (Z-Xn) 10. 
There are one or more sets of rotating discs 11, two sets being shown, to 
provide water evaporating surfaces in the evaporation zone; there are flat 
tubes 12 made of heat conductive material for forming falling absorbing 
solution films and forming falling evaporating water films in the vapor 
pressure enhancing zone, there are condenser tubes 13 and heat transfer 
fins 14 in the condensation zone to condense the second vapor streams. 
There are vapor passages 15 for transferring vapor from the evaporation 
zone (Z-En) to the vapor pressure enhancing zone (Z-VPEn); there are vapor 
passages 16 for transferring vapor from the vapor pressure enhancing zone 
(Z-VPEn) to the vapor condensing zone (Z-Xn).There are a storage and a 
pumping device 17 for an absorbing solution and there are a storage and a 
pumping device 18 for water in each pressure zone. In each vapor pressure 
enhancing zone, there is a vapor absorption zone (Z-Jn) 19 and a second 
vapor generation zone (Z-Sn) 20. The former zone is the zone outside of 
the flat tubes 12 and the latter zone is the zone inside of the flat tubes 
12. There is a pool of water 21 in the evaporation zone (Z-En) 8. 
In operation, the vessel 7 is evacuated, system water L.sub.01 is allowed 
to flow successively through Z-E1, Z-E2, Z-E3, Z-E4 and Z-E5, the rotating 
discs 11 is rotated to form water films on the disc surfaces, absorbing 
solution J.sub.on is introduced into storage tanks J.sub.n, circulating 
pumps for circulating the absorbing solutions and water are activated to 
form falling films of absorbing solution and water in the absorption zones 
(Z-Jn) 19 and the second vapor generation zones (Z-Sn) 20. Outdoor air is 
blown through the heat transfer fins in the direction from Z-1 through 
Z-5. 
Then, the system water L.sub.01 flash vaporizer successively as it flows 
through Z-E1 to Z-E5 to form first vapors V.sub.11, V.sub.22, V.sub.33, 
V.sub.44 and V.sub.55 and produces an system chill water L.sub.50 which 
becomes the chill water (L.sub.H).sub.12 of FIG. 1. It is circulated 
through the air handlers to cool the room air and be heated to become 
(L.sub.H).sub.21 of FIG. 1. The heated chill water (L.sub.H).sub.21 
becomes the L.sub.01 of the VPE/MPZ chiller. The first vapor V.sub.nn 
passes through the vapor passage 15 and is absorbed by the absorbing 
solution in the absorbing zone (Z-Jn) 19 and the heat of absorption is 
transmitted to the water in the falling water film in the second vapor 
generation zone (Z-Sn) 20 to generate second vapor V.sub.nn. The second 
vapor V.sub.nn passes through the vapor passage 16 and is condensed in the 
condenser tubes 13. The heat of condensation is transmitted through the 
heat transfer fins 14 to the outdoor air. The outdoor air flows through 
the heat transfer fins in the direction from Z-X1 to Z-X2 and is heated 
and discharged. 
As has been described, one may use cooling water to remove heats of 
condensing the second vapor streams; one may also use evaporative 
condensers in removing the heat of condensing the second vapor streams. 
FIGS. 5 and 6 respectively illustrate a vertical cross-section taken 
perpendicular to the radial direction, Section A--A, and a vertical 
cross-section parallel to the longitudinal direction, Section B--B. of a 
Type B VPE-MPZ Direct Water Chiller. Referring to these figures, a Type B 
VPE-MPZ chiller comprises a horizontal vacuum enclosure 7 and multiple 
pressure processing sub-zones. In the Figures, five processing sub-zones 
Z-1 (7a), Z-2 (7b), Z-3 (7c), Z-4 (7d) and Z-5 (7e) are illustrated. Each 
pressure sub-zone (Z-n) contains a water evaporation zone (Z-En) 8, a 
vapor pressure enhancing zone (Z-VPEn) 9, and a second vapor condensing 
zone (Z-Xn) 10. 
There are one or more sets of rotating discs 11, two sets being shown, to 
provide water evaporating surfaces in the evaporation zone; there are flat 
tubes 12 made of heat conductive material for forming falling absorbing 
solution films and forming falling evaporating water films in the vapor 
pressure enhancing zone; there are condenser tubes 13 in the condensation 
zone to condense the second vapor. There are vapor passages 15 for 
transferring vapor from the evaporation zone (Z-En) to the vapor pressure 
enhancing zone (Z-VPEn); there are vapor passages 16 for transferring 
vapor from the vapor pressure enhancing zone (Z-VPEn) to the vapor 
condensing zone (Z-Xn).There are a storage and a pumping device for 
absorbing solution and there are a storage and a pumping device for water 
in each pressure zone. These are not shown in the Figures. In each vapor 
pressure enhancing zone, there is a first vapor absorption zone (Z-Jn) 19 
and a second vapor generation zone((Z-Sn) 20. The former zone is the zone 
outside of the flat tubes 12 and the latter zone is the zone inside of the 
flat tubes 12. There is a pool of water 21 in the evaporation zone (Z-En) 
8. 
In operation, the vessel 7 is evacuated, chill water L.sub.01 is allowed to 
flow successively through Z-E1, Z-E2, Z-E3, Z-E4 and Z-E5, the rotating 
discs 11 is rotated to form water films on the disc surfaces, circulating 
pumps for circulating the absorbing solutions and water are activated to 
form falling films of absorbing solution and water in the absorption zones 
(Z-Jn) 19 and the second vapor generation zones (Z-Sn) 20. Cooling water 
is introduced into the condenser tubes 13. 
Then the system water L.sub.01 flash vaporizer successively as it flows 
through Z-E1 to Z-E5 to form first vapors V.sub.11, V.sub.22, V.sub.33, 
V.sub.44 and V.sub.55 and produces a system chill water L.sub.50 which 
becomes the chill water (L.sub.H).sub.12 of FIG. 1. It is circulated 
through the air handlers to cool the room air and be heated to become 
(L.sub.H).sub.21 of FIG. 1. The heated chill water (L.sub.H).sub.21 
becomes the L.sub.01 of the VPE/MPZ chiller. The first vapor V.sub.nn 
passes through the vapor passage 15 and is absorbed by the absorbing 
solution in the absorbing zone (Z-Jn) 19 and the heat of absorption is 
transmitted to the water in the falling water film in the second vapor 
generation zone (Z-Sn) 20 to generate second vapor V.sub.nn. The second 
vapor V.sub.nn passes through the vapor passage 16 and is condensed 
outside of the condenser tubes 13. The heat of condensation is transmitted 
through the condenser tubes to the cooling water inside. The cooling water 
flows inside the tubes in the direction from Z-X1 to Z-X5 and is heated. 
The heated cooling water is processed in a cooling tower and returned to 
the chiller. 
A VPE heater may be divided into a multitude of pressure zones and multiple 
pressure zone operations may be used to conduct the heat interactions with 
the environment, such as with outdoor air or other low temperature heat 
sources, to produce outer water vapor, absorption of the outer vapor, 
generation of inner vapor and adiabatic condensation of the inner vapor 
into system water. Such a VPE water heater may be referred to as a Vapor 
Pressure Enhancement Multiple Pressure Zone Direct Water Heater and also 
refer to as a VPE/MPZ Direct Water Heater or simply as a VPE/MPZ heater. 
Operations conducted in a multiple pressure zone VPE-heater have may 
advantages over operations conducted in a single pressure zone VPE-heater. 
These advantages are similar to the advantages of a multiple pressure zone 
VPE-chiller over a single pressure zone VPE-chiller. Therefore, a detail 
description of these advantages is omitted. 
FIG. 7 illustrates the structure and operations of a VPE/MPZ heater. Five 
pressure zone unit is illustrated. It comprises five pressure sub-zones, 
designated as Z-1 (22a) through Z-5 (22e). There are adiabatic 
liquid-vapor interaction zones, designated as Z-E1 (23a) through Z-E5 
(23e); there are vapor pressure enhancement zones, designated as Z-VPE1 
(24a) through Z-VPE5 (24e); there are environmental heat interaction 
zones, designated as Z-X1 (25a) through Z-X5 (25e). Each vapor pressure 
enhancement sub-zone, Z-VPEn, comprises an outer vapor absorption sub-zone 
Z-Jn and an inner vapor generation sub-zone Z-Sn. Therefore, there are 
outer vapor absorption zones, designated as Z-J1 through Z-J4 zones and 
inner vapor generation zones, designated as Z-S1 through Z-S5. 
The structure of the system illustrated in FIG. 7 is very similar to that 
the system illustrated by FIG. 2. There are rotating discs in Z-E1 through 
Z-E5 to provide liquid-vapor interface areas; there are flat tubes for 
forming liquid films of absorbing solution and falling water films; there 
are heat transfer tubes in Z-X1 through Z-X5 for receiving heat from the 
environment and evaporating water. 
In operation, water is added to Z-X1 through Z-X5, water is added to Z-S1 
through Z-S5, absorbing solution J.sub.05 is introduced into Z-J5 and 
diluted absorbing solutions are successively introduced into Z-J4 through 
Z-J1 as J.sub.54 through J.sub.21 and finally discharged from Z-J1 as 
J.sub.10. The absorbing solutions from falling films in Z-J1 through Z-J5 
and water forms falling films in Z-S1 through Z-S5. System water flows 
through Z-1 to Z-5. Then the following operations take place: 
1. Outer water vapor streams V.sub.11 through V.sub.55 are generated in 
Z-X1 through Z-X5; 
2. The outer water vapor streams are absorbed into absorbing solutions in 
Z-J1 through Z-J5; 
3. Water is vaporized in Z-S1 through Z-S5 upon receiving heat of 
absorption from Z-J1 through Z-J5, generating inner water vapor streams 
V.sub.11 through V.sub.55 ; 
4. The inner water vapor streams V.sub.11 through V.sub.55 condenses by 
interacting with system water to heat the system water successively. The 
system water is heated successively, L.sub.01 through L.sub.50, as it 
flows through Z-E1 to Z-E5. 
The vapor pressure enhancement operations are similar to those described by 
referring to FIG. 2. 
Z-X1 zone through Z-X5 zone are referred to as "environmental heat 
interaction zones" or simply as "heat interaction zones" and the 
operations conducted in these zones are referred to as "environmental heat 
interactions" or simply as "heat interactions". Z-E1 through Z-E5 are 
referred to as "adiabatic liquid-vapor interaction zones" and the 
operations conducted in these zones are referred to as "adiabatic 
liquid-vapor interactions" or "adiabatic condensation into system water". 
Since water is vaporized in Z-X1 through Z-X5 by receiving heat from the 
environment, such as outdoor air, the vapor streams generated, V.sub.11 
through V.sub.55 are referred to as outer water vapor streams. Since the 
water vapor streams, V.sub.11 through V.sub.55, are condensed by adiabatic 
interactions with the system water and become part of the heated system 
water, they are referred to as inner water vapor. Since the outer water 
vapor V.sub.nn and inner water vapor Vnn in a pressure zone Z-n are 
respectively the inlet vapor and outlet vapor of the vapor pressure 
enhancement operation in Z-VPEn, they are referred to respectively as the 
first vapor and second vapor in reference to the VPE operation. 
FIGS. 8 and 9 respectively illustrate a vertical cross-section. Section 
A--A, and a horizontal cross-section, Section B--B of a Type A VPE-MPZ 
Direct Water Heater. Referring to these Figures, a Type A VPE-MPZ heater 
comprises a vacuum enclosure 26 and multiple pressure processing 
sub-zones. In the figure, five processing sub-zones Z-1(26a), Z-2(26b), 
Z-3(26c), Z-4(26d) and Z-5(26e) are illustrated. Each pressure sub-zone 
(Z-n) contains an adiabatic liquid-vapor interaction zone (Z-En) 27, a 
vapor pressure enhancement zone (Z-VPEn) 28, and an environmental heat 
interaction zone (Z-Xn) 29. 
There are one or more rotating discs 30, two sets being shown, to provide 
interfacial areas in the adiabatic liquid-vapor interaction Zone (Z-En) 
27; there are flat tubes 31 made of heat conductive material for forming 
falling absorbing solution films and forming falling and evaporating water 
films in the vapor pressure enhancing zone; there are heat transfer tubes 
32 and heat transfer fins 33 in the heat interaction zone (Z-Xn) 29 to 
generate the outer vapor streams. There are vapor passages 34 for 
transferring vapor from the vapor pressure enhancing zone (Z-VPEn) 28 to 
the adiabatic liquid-vapor interaction zone (Z-En) 27; there are vapor 
passages 35 for transferring outer vapor from the heat interaction zone 
(Z-Xn) 29 to the vapor pressure enhancement zone (Z-VPEn) 28. There are a 
storage and a pumping device 36 for an absorbing solution and there are a 
storage and a pumping device 37 for water in each pressure zone. In each 
vapor pressure enhancing zone, there is a vapor absorption zone (Z-Jn) 39 
and a inner vapor generation zone (Z-Sn) 38. The former zone is the zone 
inside of the flat tubes 31 and the latter zone is the zone outside of the 
flat tubes 31. There is a pool of water 40 in the adiabatic liquid-vapor 
interaction zone (Z-En) 27. 
In operation, the vessel 26 is evacuated, system water L.sub.01 is allowed 
to flow successively through Z-E1, Z-E2, Z-E3, Z-E4 and Z-E5, the rotating 
discs 30 is rotated to form water films on the disc surfaces, absorbing 
solution J.sub.on is introduced into storage tanks J.sub.n circulating 
pumps for circulating the absorbing solutions and water are activated to 
form falling films of absorbing solution and water in the absorption zone 
(Z-Jn) 39 and the inner vapor generation zones (Z-Sn) 38. Water is added 
to the heat transfer tubes 32 to form falling water films and outdoor air 
is blown through the heat transfer fins in the direction from Z-1 through 
Z-5. Then the following operations take place: 
1. Water vaporizes in Z-X1 through Z-X5 to generate outer water vapors 
V.sub.11 through V.sub.55 ; 
2. The outer water vapor streams are absorbed into the absorbing solution 
in Z-VPE1 through Z-VPE5; 
3. The heats of absorption generated in Z-J1 through Z-J5 are transferred 
to Z-S1 through Z-S5 to generate inner water vapor streams V.sub.11 
through V.sub.55 ; 
4. The inner water vapor streams are condensed by adiabatically interacting 
with system water in Z-E1 through Z-E5 to heat the system water L.sub.01 
successively to become heated system water L.sub.50. 
One may construct and operate a Type B VPE-MPZ Direct Water Heater. Its 
structure is similar to that of a VPE-MPZ Direct Water Chiller illustrated 
by FIG. 5 and 6 and the operations are similar to those described in 
connection with the Type A VPE-MPZ heater described. Therefore, a detail 
description of Type B VPE-MPZ is omitted. 
Since the structure and operations of a VPE-heater and a VPE-chiller are 
very close, one can construct and operate a dual purpose VPE 
chiller/heater.