U.S. patent application number 12/680576 was filed with the patent office on 2010-08-26 for system and method for extracting atmospheric water.
This patent application is currently assigned to Sin Hui TEO. Invention is credited to Chee Keong Oh.
Application Number | 20100212348 12/680576 |
Document ID | / |
Family ID | 40526463 |
Filed Date | 2010-08-26 |
United States Patent
Application |
20100212348 |
Kind Code |
A1 |
Oh; Chee Keong |
August 26, 2010 |
SYSTEM AND METHOD FOR EXTRACTING ATMOSPHERIC WATER
Abstract
The earth consists mainly of water and water exists on the
earth's surface, in aquifers in the soil as groundwater, and in the
atmosphere as water vapour. However, of all the water on earth,
only less than 3 percent is fresh water. Due to factors such as
climate changes, environmental pollution, as well as population
growth, the available amount of fresh water sources is dwindling
rapidly. In addition, there are many problems associated with
provision of potable water using existing techniques. One way to
overcome the aforementioned problems is to extract water from the
atmosphere. However, hardware costs of current commercial systems
are relatively high and they are not efficient in terms of
performance. An embodiment of the invention provides a system and a
method for obtaining potable water by extracting atmospheric
water.
Inventors: |
Oh; Chee Keong; (Singapore,
SG) |
Correspondence
Address: |
EAGLE IP LIMITED
13/F, Bright Way Tower, 33 Mong Kok Road
Kowloon
HK
|
Assignee: |
TEO; Sin Hui
Singapore
SG
|
Family ID: |
40526463 |
Appl. No.: |
12/680576 |
Filed: |
July 18, 2008 |
PCT Filed: |
July 18, 2008 |
PCT NO: |
PCT/SG08/00260 |
371 Date: |
March 29, 2010 |
Current U.S.
Class: |
62/291 ;
165/104.31; 165/165 |
Current CPC
Class: |
B01D 53/323 20130101;
B01D 5/0039 20130101; Y02A 20/109 20180101; B01D 5/0006 20130101;
B01D 53/265 20130101; B01D 5/009 20130101; Y02A 20/00 20180101 |
Class at
Publication: |
62/291 ; 165/165;
165/104.31 |
International
Class: |
F25D 21/14 20060101
F25D021/14; F28D 7/02 20060101 F28D007/02; F28D 15/00 20060101
F28D015/00 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 1, 2007 |
SG |
200716417-1 |
Claims
1. An atmospheric water extraction system comprising: a passage
having a condenser portion and a cooling portion inter-configured
for cyclical passage of fluid therethrough; a cooling unit in
thermal communication with the cooling portion for extracting heat
from liquid passaging through the cooling portion to thereby cool
the liquid, the liquid being transportable to the condenser portion
subsequent to passaging through the cooling portion; and an ioniser
for ionising ambient air into ionised air, the ionised air being
charged for enhancing adhesion of water vapour thereto, wherein the
ionised air is transportable for thermal interaction with the
condenser portion of the passage for condensing the water vapour
into water droplets, the liquid passaging through the condenser
portion receiving heat from the ionised air during thermal
interaction of the ionised air with the condenser portion, the
liquid being transportable to the cooling portion of the passage
for re-cooling thereby subsequent to passaging through the
condenser portion.
2. The atmospheric water extraction system as in claim 1, wherein
the liquid passaging through the passage is substantially
isobaric.
3. The atmospheric water extraction system as in claim 1, further
comprising: a ventilator for displacing the ambient air into the
atmospheric water extraction system, the ventilator being operable
for controlling flow rate of the ambient air displaced.
4. The atmospheric water extraction system as in claim 1, further
comprising: an air filter for filtering the ambient air for being
received by the ioniser.
5. The atmospheric water extraction system as in claim 1, wherein
the cooling unit comprises a drive assembly for displacing the
liquid from the cooling unit to the condenser portion of the
passage.
6. The atmospheric water extraction system as in claim 5, wherein
the drive assembly comprises an actuator valve and one of a fluid
pump, a displacement pump and a centrifugal pump.
7. The atmospheric water extraction system as in claim 5, wherein
the cooling unit further comprises a temperature measurement device
for measuring the temperature of the liquid.
8. The atmospheric water extraction system as in claim 4, wherein
the cooling unit is couplable to an external cooling source, the
external cooling source for extracting heat from the liquid.
9. The atmospheric water extraction system as in claim 1, further
comprising a water collection tray for receiving the water droplets
from the condenser portion.
10. The atmospheric water extraction system as in claim 9, further
comprising a water collection tank for receiving the water droplets
from the water collection tray.
11. The atmospheric water extraction system as in claim 10, wherein
the water collection tank comprises a water level measurement
device and a water purifier.
12. The atmospheric water extraction system as in claim 1, further
comprising a temperature measurement device for measuring ambient
air temperature and a relative humidity measurement device for
measuring relative humidity of the ambient air.
13. An atmospheric water extraction method comprising: providing a
passage having a condenser portion and a cooling portion
inter-configured for cyclical passage of fluid therethrough;
extracting heat from liquid passaging through a cooling portion to
thereby cool the liquid using a cooling unit, the cooling unit in
thermal communication with the cooling portion, the liquid being
transportable to the condenser portion subsequent to passaging
through the cooling portion; and ionising ambient air into ionised
air using an ioniser, the ionised air being charged for enhancing
adhesion of water vapour thereto, wherein the ionised air is
transportable for thermal interaction with the condenser portion of
the passage for condensing the water vapour into water droplets,
the liquid passaging through the condenser portion receiving heat
from the ionised air during thermal interaction of the ionised air
with the condenser portion, the liquid being transportable to the
cooling portion of the passage for re-cooling thereby subsequent to
passaging through the condenser portion.
14. The atmospheric water extraction method as in claim 13, wherein
the liquid passaging through the passage is substantially
isobaric.
15. The atmospheric water extraction method as in claim 13, further
comprising: displacing the ambient air using a ventilator, the
ventilator being operable for controlling flow rate of the ambient
air displaced.
16. The atmospheric water extraction method as in claim 13, further
comprising: filtering the ambient air for being received by the
ioniser using an air filter.
17. The atmospheric water extraction method as in claim 13, wherein
the cooling unit comprises a drive assembly for displacing the
liquid from the cooling unit to the condenser portion of the
passage.
18. The atmospheric water extraction method as in claim 17, wherein
the drive assembly comprises an actuator valve and one of a fluid
pump, a displacement pump and a centrifugal pump.
19. The atmospheric water extraction method as in claim 17, wherein
the cooling unit further comprises a temperature measurement device
for measuring the temperature of the liquid.
20. The atmospheric water extraction method as in claim 16, wherein
the cooling unit is couplable to an external cooling source, the
external cooling source for extracting heat from the liquid.
21. The atmospheric water extraction method as in claim 13, further
comprising: receiving the water droplets from the condenser portion
using a water collection tray.
22. The atmospheric water extraction method as in claim 21, further
comprising: receiving the water droplets from the water collection
tray using a water collection tank.
23. The atmospheric water extraction method as in claim 22, wherein
the water collection tank comprises a water level measurement
device and a water purifier.
24. The atmospheric water extraction method as in claim 13, further
comprising: providing a temperature measurement device for
measuring ambient air temperature and providing a relative humidity
measurement device for measuring relative humidity of the ambient
air.
25. An atmospheric water extraction system comprising: an ioniser
for ionising ambient air for obtaining ionised air therefrom, the
ionised air being charged for enhancing adhesion of water vapour
thereto; and a condenser portion disposed alongside the ioniser for
condensing water vapour in the ionised air into water droplets.
Description
FIELD OF INVENTION
[0001] The present field of invention generally relates to
extraction of atmospheric water. More particularly, it relates to a
system and a method for obtaining potable water from extracting
atmospheric water.
BACKGROUND
[0002] The earth consists mainly of water and water exists on the
earth's surface, in aquifers in the soil as groundwater, and in the
atmosphere as water vapour. Of all the water on earth, only less
than 3 percent is fresh water. However, as majority of fresh water
is trapped in ice caps, glaciers and aquifers, only less than 1
percent of the water supply on earth is portable and available for
drinking purposes.
[0003] In recent years, global concerns regarding insufficient
fresh water sources have increased greatly. Currently, sources of
fresh water include water provided by lakes, rivers, and artesian
wells. Unfortunately, these fresh water sources are not sustainable
because of decline both in capacity and purity at alarming rates
due to expansion of deserts. Furthermore, factors such as climate
changes, environmental pollution, as well as population growth
further threaten existing fresh water sources.
[0004] Besides having insufficient fresh water sources, there are
also problems associated with provision of potable water. The
provision of potable water is a serious problem in areas where
rainfall is scarce, seasonal, or where there are relatively small
water catchment areas and little natural local water storage.
Additionally, as fresh water sources are not evenly distributed
globally, some geographical locations do not have ready access to
fresh water. Constructing reservoirs and water desalination plants
usually alleviates this problem. However, many countries are unable
to afford water desalination plants due to the relatively high
capital investment and operational costs required.
[0005] Another problem associated with the provision of potable
water relates to the setting up and maintenance of potable water
distribution networks, such as water piping networks, which require
significant efforts and resources. Further, water piping networks
have limited lifespan and are frequently associated with water
leakage and contamination problems. Water piping networks typically
use water pipes made from metal ducts, concrete ducts or polyvinyl
chloride (PVC) pipes. Metal and concrete ducts are vulnerable to
corrosion by inorganic acid and alkaline contaminants, whereas
organic solvents present in soil and building materials can be
absorbed by and permeated through PVC pipes.
[0006] One way to overcome the aforementioned problems is by
extracting water from the atmosphere. Approximately 577,000
km.sup.3 of water evaporates into the atmosphere from water bodies,
such as seas and rivers, and the earth's surface each year, with
air remaining close to the earth's surface containing the greatest
percentage of water. Commercial water production systems capable of
extracting atmospheric water have made it possible to supply
potable water without the need for tapping on a central water
source via complex water distribution networks. Such water
production systems are therefore an attractive alternative to
conventional ways of deriving and distributing potable water.
[0007] In principle, these commercial water production systems
collect water droplets formed by condensation of water vapour
present in the atmosphere on cold surfaces cooled by refrigeration
means. The working principle is similar to the disclosure in
patents filed to Ehrlich in 1978 (U.S. Pat. No. 4,255,937), Reidy
(U.S. Pat. No. 5,106,512, U.S. Pat. No. 5,149,446, U.S. Pat. No.
5,203,989) and Morgen et al. in 2002 (U.S. Pat. No. 6,931,756B2).
With the advent of more efficient refrigeration techniques, the
cost of electricity needed for extracting an amount of water from
the atmosphere can be lower than the price of a bottled water of
equivalent volume, or that of the utility charge of obtaining an
equivalent volume of water from the tap with the additional cost
for boiling or purifying water using mechanical and chemical
filtering means.
[0008] However, the cost of hardware of a commercial water
production system comprising compressor, condenser, evaporator and
filtration means remains relatively high leading to unattractive
return of investment. Additionally, for climates with low ambient
temperature levels or where temperature fluctuates significantly,
atmospheric water extraction becomes difficult. Typically, these
commercial water production systems for water vapour extraction
operate above 20.degree. C. and above a relative humidity of
35%.
[0009] U.S. Pat. No. 3,675,442 to Swanson discloses an atmospheric
water collector, which employs a cooling coil immersed in a fresh
water bath that cools the bath. The cooled water is pumped through
a conduit and condensing frame. Water vapour present in winds that
pass over the condensing frame is condensed and drained into a
collector. However, the cooled water is periodically mixed with the
condensed water subjecting the condensed water to
contamination.
[0010] U.S. Pat. No. 5,056,593 to Hull discloses, in several
variations, the use of electrostatic and magnetic fields to
substantially enhance water product extraction yields in a
dehumidifying heat exchanger apparatus. Liquid water droplets are
electrostatically collected on grounded or charged heat transfer
tubes in the heat exchanger apparatus. In one variation, charged or
grounded horizontally-declined heat transfer tubes with attached
drainage wicks attract liquid droplets and accelerate condensing
heat transfer by continuous absorption and transfer of condensate.
The use of drainage wicks to absorb and confine condensate
collected on the surfaces of the heat transfer tubes may result in
the loss of water extracted and advance the growth of fungi and
bacteria on the drainage wicks. Additionally, the heat exchanger
apparatus may be electrically unsafe with charged electrode wires
entrenched between the tubes of the heat exchange unit.
[0011] U.S. Pat. No. 7,000,410 to Hutchinson discloses a device
that utilizes a condenser type refrigerant system with multiple
fans and two air chambers to produce water from the air. The
apparatus further deploys a stainless steel ioniser to charge the
ambient air to maximise extraction of moisture from the air. The
two air chambers operate in tandem to mix desiccated ionised air
that exited from the evaporator plates with fresh incoming air
drawn through a compressor, a condenser and the ioniser. This
causes partial drying of the newly formed condensation, which
results in loss of condensation leading to reduced output and
efficiency.
[0012] JP Pat. No. 02,172,587 to Katsumi and U.S. Pat. No.
5,435,151 to Han disclose water making apparatus for use on
vehicles. U.S. Pat. App. No. 20040040322 filed by Engel et al.
discloses a similar water extraction device for vehicles, together
with some applications including central air system and mobile
unit. All the disclosed devices tap on existing or external air
conditioning systems to simplify system design and lower device
cost. However, conventional designs fail to function properly in
many temperate areas where ambient temperature drops below
20.degree. C. during the night or during cold spells and storms.
This problem accentuates for water extraction devices installed on
vessels and ships, on caravans and emergency vehicles.
[0013] Therefore, there is a need for a system and a method for
obtaining potable water from extracting atmospheric water, which at
least addresses one of the aforementioned disadvantages.
SUMMARY
[0014] The present embodiment of the invention disclosed herein
provides an atmospheric water extraction system and a method for
extracting atmospheric water for obtaining potable water.
[0015] In accordance with a first aspect of the invention, there is
disclosed an atmospheric water extraction system comprising a
passage, a cooling unit and an ioniser. The passage comprises a
condenser portion and a cooling portion inter-configured for
cyclical passage of fluid therethrough. The cooling unit is in
thermal communication with the cooling portion and is for
extracting heat from liquid passaging through the cooling portion
to thereby cool the liquid, in which the liquid is transportable to
the condenser portion subsequent to passaging through the cooling
portion. The ioniser is for ionising ambient air into ionised air,
in which the ionised air is charged for enhancing adhesion of water
vapour thereto. The ionised air is transportable for thermal
interaction with the condenser portion of the passage for
condensing the water vapour into water droplets, and the liquid
passaging through the condenser portion receives heat from the
ionised air during thermal interaction of the ionised air with the
condenser portion. The liquid is then transportable to the cooling
portion of the passage for re-cooling thereby subsequent to
passaging through the condenser portion.
[0016] In accordance with a second aspect of the invention, there
is disclosed an atmospheric water extraction method. The method
comprises providing a passage having a condenser portion and a
cooling portion inter-configured for cyclical passage of fluid
therethrough. The method also comprises extracting heat from liquid
passaging through a cooling portion to thereby cool the liquid
using a cooling unit, whereby the cooling unit is in thermal
communication with the cooling portion. The liquid is then
transportable to the condenser portion subsequent to passaging
through the cooling portion. The method further comprises ionising
ambient air into ionised air using an ioniser, in which the ionised
air is charged for enhancing adhesion of water vapour thereto. The
ionised air is transportable for thermal interaction with the
condenser portion of the passage for condensing the water vapour
into water droplets, and the liquid passaging through the condenser
receives heat from the ionised air during thermal interaction of
the ionised air with the condenser portion. The liquid is then
transportable to the cooling portion of the passage for re-cooling
thereby subsequent to passaging through the condenser portion.
[0017] In accordance with a third aspect of the invention, there is
disclosed an atmospheric water extraction system comprising an
ioniser and a condenser portion. The ioniser ionises ambient air
for obtaining ionised air therefrom, in which the ionised air is
charged for enhancing adhesion of water vapour thereto. The
condenser portion is disposed alongside the ioniser for condensing
water vapour in the ionised air into water droplets.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] An embodiment of the invention is described hereinafter with
reference to the following drawings, in which:
[0019] FIG. 1 shows a partial schematic diagram of an atmospheric
water extraction system according to an embodiment of the
invention; and
[0020] FIG. 2 shows an operational flow of the atmospheric water
extraction system of FIG. 1.
DETAILED DESCRIPTION
[0021] An atmospheric water extraction system and a method for
extracting atmospheric water are described hereinafter for
addressing at least one of the aforementioned disadvantages.
[0022] For purposes of brevity and clarity, the description of the
invention is limited hereinafter to applications relating to
atmospheric water extraction. This however does not preclude
various embodiments of the invention from other applications. The
fundamental inventive principles of the embodiments of the
invention shall remain common throughout the various
embodiments.
[0023] An embodiment of the invention described in the detailed
description provided hereinafter is in accordance with FIG. 1 and
FIG. 2 of the drawings, in which like elements are numbered with
like reference numerals.
[0024] With reference to FIG. 1, an atmospheric water extraction
system 100 (hereinafter known as system 100) for extracting
atmospheric water is described according to an embodiment of the
invention. The system 100 generally comprises an extraction unit
110, a passage 111, a water collection unit 112 and a cooling unit
113.
[0025] The extraction unit 110 is for extracting water vapour in
ambient air and the extraction unit 110 has an intake 114 and an
exhaust 116 formed therein for allowing flow of the ambient air
therethrough. The extraction unit 110 comprises an ioniser 118 and
a condenser portion 120, in which the condenser portion 120 is
disposed alongside the ioniser 118. The extraction unit 110 further
comprises an air filter 122, a ventilator 124 and a water
collection tray 126.
[0026] The ioniser 118 is for ionising the ambient air into ionised
air. When the ioniser 118 ionises the ambient air, air particles
present in the ambient air become positively or negatively charged,
although negative charging is preferable in most uses. The charged
air particles (ionised air) enhance adhesion of water vapour
thereto for extracting atmospheric water over varying ambient
temperatures and humidity. Due to the polar nature of water, each
water molecule has an electric dipole moment. The oxygen atom in
each water molecule has a partial negative charge while each
hydrogen atom in each water molecule has a partial positive charge.
As such, the difference in charge causes water molecules to be
attracted to each other and to other polar molecules. Since the
ionised air comprises charged particles, adhesion of water vapour
thereto is enhanced due to the partial negative and positive
charges present on water molecules. The ioniser 118 is also for
sterilising the ambient air and for inhibiting growth of fungi and
bacteria when the system 100 is in use.
[0027] The condenser portion 120 is for condensing water vapour in
the ionised air to obtain water droplets. The ionised air is
transportable for thermal interaction with the condenser portion
120 for condensation of water vapour to take place. Condensation of
water vapour occurs when a surface is colder than the dew point
temperature (condensation threshold temperature) of the air
surrounding the surface. At this temperature, the air has a
relative humidity of equivalent to 100 percent and the air becomes
saturated with water. The dew point temperature of the air is
dependent on both air temperature and humidity. Therefore, surfaces
of the condenser portion 120 over which the ionised air flows must
have a temperature that is lower than the dew point of the ionised
air.
[0028] The passage 111 is inter-configured for cyclical passage of
fluid therethrough. The passage 111 comprises a first fluid channel
128 and a second fluid channel 130 for interconnecting the
extraction unit 110 and the cooling unit 113. The first fluid
channel 128 is for receiving liquid from the cooling unit 113 and a
second fluid channel 130 for returning the liquid to the cooling
unit 113. The cooling unit 113 is in thermal communication with a
cooling portion 132 for extracting heat from the liquid passaging
through the cooling portion 132 to thereby cool the liquid. The
liquid is then transportable to the condenser portion 120
subsequent to passaging through the cooling portion 132 for cooling
the surfaces of the condenser portion 120 to a temperature that is
lower than the dew point temperature of the air surrounding the
surfaces for condensation of water vapour to occur. The surfaces of
the condenser portion 120 can be made of any material of which
water vapour condensation can occur in response to cooling of the
material in a given environment. For instance, the material can
comprise of metal, glass, plastic, or the like.
[0029] Additionally, the surfaces of the condenser portion 120 are
film-coated with food-grade materials, such as, gold, tin, Teflon
or the like in compliance with public health requirements governing
use of materials in contact with drinking water. The surfaces of
the condenser portion 120 are preferably plated with gold or any
material of which enhances the rate of heat transfer. The condenser
portion 120 is preferably designed for optimising air circulation,
velocity and distribution of air on the surfaces for achieving an
optimal rate of water vapour extraction.
[0030] The cooling unit 113 comprises a drive assembly 136 for
displacing the liquid from the cooling unit 113 to the condenser
portion 120 via the first fluid channel 128. The drive assembly 136
comprises an actuator valve 138 and a fluid pump 140. The fluid
pump 140 is one of a centrifugal pump and a displacement pump.
Further, the cooling unit 113 is couplable to an external cooling
source (not shown) for extracting heat from the liquid to cool
liquid. The external cooling source can comprise a refrigerant,
such as Freon, for extracting heat from the liquid. As such,
instead of relying on the cooling portion 132 for extracting heat
from the liquid, the cooling unit 113 can tap on the external
cooling source for cooling the liquid. The liquid is one of water
and alcohol, or the like. The cooling unit 113 further comprises a
temperature measurement device 142 for measuring the temperature of
the liquid passing therethrough. The temperature of the liquid is
preferably in the range of 5.degree. C. to 15.degree. C.
[0031] Prior to ionisation of the ambient air by the ioniser 118,
the ambient air is passed through the air filter 122 of the
extraction unit 110. The air filter 122 is for filtering the
ambient air and is disposed in the vicinity of the ioniser 118. The
air filter 122 can also be disposed in the intake 114 or in the
vicinity of the intake 114. Furthermore, the air filter 122 is
replaceable and therefore can be replaced when necessary.
[0032] The ventilator 124, on the other hand, is disposed in the
vicinity of the condenser portion 120 and is for displacing and
directing the ambient air into the extraction unit 110. The
ventilator 124 is preferably a form or the like impeller-based air
mover controllable to vary flow rate of the ambient air. By varying
the flow rate of the ambient air, convecting air currents necessary
for obtaining sufficient water vapour condensation on the surfaces
of the condenser portion 120 is generatable. The ventilator 124 can
also be disposed at or adjacent the exhaust 116. The air filter 122
and the ventilator 124 are orientable or disposed as readily
recognised by those skilled in the art to achieve effectively clean
or dust-controlled airflow or circulation inside the extraction
unit 110.
[0033] The water collection tray 126 of the extraction unit 110 is
for receiving the water droplets from the condenser portion 120.
The water collection tray 126 is disposed in the extraction unit
110 such that the water droplets received are directed to the water
collection unit 112. The water collection unit 112 of the system
100 comprises a water collection tank 144, a drive assembly 146 and
a water purifier 148.
[0034] The water collection tank 144 is for receiving the water
droplets from the water collection tray 126. The water collection
tank 144 preferably comprises a sediment filter (not shown) for
filtering the water droplets received. The water collection tank
144 further comprises a water level measurement device 150 for
measuring the water level present in the water collection tank 144
and a water purifier 152 for purifying the water droplets received.
The water level measurement device 150 is an optical or a float
switch type while the water purifier 152 preferably comprises an
ultra-violet light or an ozone generator. Further, the water
purifier 152 may incorporate other filtration means including any
mechanical, chemical or biological filtering systems suitable for
purifying water for drinking purposes.
[0035] The drive assembly 146 is for transporting water collected
in the water collection tank 144 to the water purifier 148 of the
water collection unit 112. The drive assembly 146 is one of a fluid
pump, a centrifugal pump and a displacement pump. The drive
assembly 146 provides additional gravitational pressure to extract
the water collected out of the water collection tank 144 and
displace the water through the water purifier 148. The water
purifier 148 comprises any suitable device capable of sterilising
water, for instance, suitable chemical means, heating elements,
ultra-violet radiation emitters, or the like. The water after
passing through the water purifier 148 is suitable for drinking and
can be transported through a fluid duct 153 to external appliances
or any storage.
[0036] The system 100 further comprises a temperature measurement
device 154 for measuring ambient air temperature and a relative
humidity measurement device 156 for measuring relative humidity of
the ambient air. Additionally, the system 100 further comprises a
controller 158 for controlling the system 100. The controller 158
is couplable to a signalling interface module for relaying any
control signals for operating any electrically driven parts and
components of the system 100 that require instructions, signalling
and/or electricity supply.
[0037] The controller 158 preferably comprises a microprocessor
(not shown) for storing and executing software applications or
embedded codes capable of generating appropriate control signals in
accordance with a set of pre-programmed instructions. Measured data
is further processable in the controller 158 in which the processes
include logging, reading and writing, storing and backing-up,
analysing and displaying of measured and/or control data. Further,
the controller 158 is coupled to external computing equipment via a
wired or wireless data exchange interface (not shown). Finally,
electrical power supplied to the controller 158 and the system 100
may be single-phase or multi-phase alternating current tapped from
power grids or mobile electricity generators such as those used on
vessels, cruises, caravans, oil rigs, construction sites and other
similar facilities. Alternatively, electrical power can be supplied
as direct current.
[0038] FIG. 2 illustrates the operational flow 200 of the system
100. Upon supplying electrical power to the system 100, in a step
210, the controller 158 activates the ioniser 118 and the
ventilator 124. Further, the controller 158 samples data measured
by the temperature measurement device 142 of the cooling unit 113,
the water level measurement device 150, the temperature measurement
device 154 of the system 100 and the relative humidity measurement
device 156 at a predetermined regular interval to obtain measured
data therefrom. The controller 158 then analyses the measured data
and determines the mode of operation, and may display the measured
data for visual monitoring by an operator of the system 100 in a
step 212.
[0039] Next in a step 214, the controller 158 retrieves the
required controls according to the mode of operation that is
determined in the step 212. Further, in a step 216, the controller
158 looks up required controls for required parts of the system 100
based on the measured data. Finally, in a step 218, corresponding
control signals provided by the steps 214 and 216 are sent to the
corresponding elements of the system 100.
[0040] An example of operating the system 100 is provided
hereinafter.
[0041] The controller 158 selects a first mode of operation denoted
as a NORMAL mode when (a) the ambient temperature measured by the
temperature measurement device 154 is greater than a first
predetermined threshold TLA.sub.01, (b) the ambient relative
humidity measured by the relative humidity measurement device 156
is greater than a first predetermined level RHL.sub.01, (c) the
temperature of the liquid from the cooling portion 132 measured by
the temperature measurement device 142 is lower than a
predetermined threshold of TLC.sub.HI, (d) the water level in the
water collection tank 144 detected by the water level measurement
device 150 does not exceed a predetermined level WLC.sub.HI, and
(e) if an external water storage tank is present (coupled to the
system 100) and the external water storage tank does not indicate
FULL state (not shown).
[0042] If the above conditions are met, the controller 158 opens
the actuator valve 138 to allow the liquid from the cooling portion
132 to flow into the first fluid channel 128. Further, the
controller 158 activates the fluid pump 140 to convey the liquid to
the condenser portion 120 via the first fluid channel 128. The
liquid is then circulated from the condenser portion 120 back to
the cooling portion 132 by means of the second fluid channel 130.
The liquid passaging through the condenser portion 120 receives
heat from the ionised air during thermal interaction of the ionised
air with the condenser portion 120. The liquid is then
transportable to the cooling portion 132 of the passage 111 for
re-cooling thereby subsequent to passaging through the condenser
portion 120. The liquid passaging through the passage 111 is
substantially isobaric.
[0043] Excessive airflow generated by the ventilator 124 may hamper
the extraction of water vapour from the ambient air. As such, the
speed of the airflow generated by the ventilator 124 should
preferably be controlled at a predetermined optimised rate. The
controller 158 can control the ventilator 124 and the controller
158 attains a predetermined airflow by adjusting fan speed of the
ventilator 124. In the first mode of operation, the controller 158
sets the fan speed of the ventilator 124 to low or medium. The
ambient air is then controllably induced into the system 100 by the
ventilator 124. The incoming air first passes through the air
filter 122 followed by an ionising field created by the ioniser
118. The ionised air then passes through the condenser portion 120
and surrounds the surfaces of the condenser portion 120 in which
condensation of water vapour takes place. The water droplets
obtained after condensation drips onto the water collection tray
126 and are directed into the water collection tank 144. The water
level measurement device 150 measures the water level present in
the water collection tank 144 to detect predetermined high
(WLC.sub.HI) and low (WLC.sub.LO) water levels.
[0044] During the NORMAL mode and when the water level detected by
the water level measurement device 150 exceeds a predetermined
level low (WLC.sub.LO) level, the water purifier 152 in the water
collection tank 144 is activated by the controller 158 on either a
continuous or regular basis with the water purifier 152 being
periodically activated for a first duration of WPU.sub.ON1 and
deactivated for a second duration of WPU.sub.OFF1. When the water
level measured by the water level measurement device 150 detects a
predetermined high (WLC.sub.HI) level, and if the external water
storage tank is present and the external water storage tank does
not indicate the FULL state, the controller 158 activates the drive
assembly 146 to transfer the water from the water collection tank
144 through the water purifier 148 of the water collection unit
112. The controller 158 can activate the water purifier 148 on
either a continuous or regular basis.
[0045] The controller 158 selects a second mode of operation
denoted as a COLD mode when (a) the ambient temperature measured by
the temperature measurement device 154 falls between the first
predetermined threshold TLA.sub.01 and a second predetermined
threshold TLA.sub.02, (b) the ambient relative humidity measured by
the relative humidity measurement device 156 is equal to or greater
than the predetermined level RHL.sub.LO, (c) the temperature of the
liquid from the cooling portion 132 measured by the temperature
measurement device 142 equals to or lower than the predetermined
threshold of TLC.sub.LO, (d) the water level in the water
collection tank 144 detected by the water level measurement device
150 does not exceed the predetermined level WLC.sub.HI, and (e) if
the external water storage tank is present (coupled to the system
100) and the external water storage tank does not indicate FULL
status (not shown).
[0046] If the above conditions are met, the controller 158 operates
the system 100 through the same control and decision-making steps
as performed for the NORMAL mode. The only exception is that the
fan speed of the ventilator 124 is set to high for increasing the
air circulation in the vicinity of the condenser portion 120,
leading to higher water vapour condensation efficiency when the
ambient air temperature is low.
[0047] The controller 158 selects a third mode of operation denoted
as a SUSPEND mode when (a) the ambient temperature measured by the
temperature measurement device 154 falls below the second
predetermined threshold TLA.sub.02, or (b) the ambient relative
humidity measured by the relative humidity measurement device 156
falls below a second predetermined level RHL.sub.02, or (c) the
temperature of the liquid from the cooling portion 132 measured by
the temperature measurement device 142 is higher than a
predetermined threshold of TLC.sub.HI, or (d) the water level in
the water collection tank 144 detected by the water level
measurement device 150 equals or exceeds the predetermined level
WLC.sub.HI, or (e) if the external water storage tank is present
(coupled to the system 100) and the external water storage tank
indicates FULL state (not shown).
[0048] If any of the above conditions is met, the controller 158
stops all the steps required to extract water vapour. However, the
ioniser 118 and the ventilator 124 can continue to operate
controllably by the controller 158. The controller 158 may also
continue to monitor all measurement means if any. Further, should
the water level in the water collection tank 144 is above
WLC.sub.LO, the controller 158 may continue to activate the water
purifier 152 of the water collection tank 144 on a continuous or
periodic basis.
[0049] Exemplary parameters that are preferably used in the system
100 for extracting atmospheric water are as follows:
1) TLA.sub.01=25.degree. C. and TLA.sub.02=15.degree. C., as
temperature threshold values used for classifying the modes of
operation; 2) RHL.sub.01=50% and RHL.sub.02=25%, as relative
humidity threshold values used for classifying the modes of
operation; 3) TLC.sub.LO=5.degree. C. and TLC.sub.HI=15.degree. C.,
as temperature threshold values of the liquid being cooled by the
cooling portion 132 used for activation and deactivation of the
actuator valve 138 and drive assembly 146; and 4) WPU.sub.ON=30
seconds and WPU.sub.OFF1=45 minutes, for periodic activation and
cut off durations of the water purifier 152 of the water collection
tank 144.
[0050] The system 100 for extracting water vapour from the ambient
air for obtaining potable water provides a solution to water
harvesting without the need for extensive water distribution
networks. Hence, the system 100 is well suited for indoor, outdoor,
fixed and mobile applications. Further, as the system 100 is able
to ride on external cooling sources such as existing refrigeration
and central air system for extracting heat from the liquid for
cooling the liquid, the system 100 offers a cost-effective water
making system with relatively low equipment, operational and
maintenance costs.
[0051] Furthermore, the system 100 is able to operate at an ambient
air temperature of as low as 15.degree. C., thus making the system
100 well suited for many indoor and outdoor, fixed and mobile
applications not only in tropical regions, but also in temperate
areas with ambient air temperatures well below what conventional
systems are designed to operate at.
[0052] In the foregoing manner, an atmospheric water extraction
system and a method for extracting atmospheric water are described
according to one embodiment of the invention for addressing at
least one of the foregoing disadvantages. Although only one
embodiment of the invention is disclosed, the invention is not to
be limited to specific forms or arrangements of parts so described
and it will be apparent to one skilled in the art in view of this
disclosure that numerous changes and/or modification can be made
without departing from the scope and spirit of the invention.
* * * * *