Note: Descriptions are shown in the official language in which they were submitted.
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METHODS AND APPARATUS FOR DISTILLATION
Cross-Reference to Related Application
[0001] This application claims priority to U.S. Provisional Application Serial
No.
60/864,899, entitled "Liquid Purification System," filed on November 8, 2006,
which is
incorporated herein by reference in its entirety. This application also claims
priority to and is
a continuation of U.S. Nonprovisional Application Serial No. 11/936,657,
entitled "Methods
and Apparatus for Distillation Using Phase Change Energy," filed on November
7, 2007,
U.S. Nonprovisional Application Serial No. 11/936,740, entitled "Methods and
Apparatus for
Distillation of Shallow Depth Fluids," filed on November 7, 2007, and U.S.
Nonprovisional
Application Serial No. 11/936,741, entitled "Methods and Apparatus for Signal
Processing
Associated with Phase Change Distillation," filed on November 7, 2007, all of
which are
incorporated herein by reference in their entireties.
Background
[0002] Embodiments of the invention relate generally to distillation, and in
particular, to
methods and apparatus for efficient distillation over a wide range of
temperatures and
pressures.
[0003] A number of known devices and methods have been utilized to distill (or
separate) a fluid from a mixture of fluids. For example, known desalinators
can be used to
purify seawater to produce fresh water of a lower salinity for irrigation or
drinking purposes.
Known distillation devices and methods, however, are often complex, operate at
high
pressures and/or temperatures, and require large quantities of power due to
inefficiencies.
Thus, a need exists for a distillation apparatus and methods that can enable
efficient
operation over a wide range of temperatures and/or pressures.
Summary of the Invention
[0004] In one embodiment, a method includes moving a first volume of fluid
from a
region above a heat-transfer element to a region below the heat-transfer
element after the first
volume of fluid is boiled from a second volume of fluid within the region
above the heat-
transfer element. The first volume of fluid including an impurity
concentration lower than an
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impurity concentration of the second volume of fluid. The region below the
heat-transfer
element has a temperature higher than a temperature of the region above the
heat-transfer
element. The method also includes transferring latent heat from the first
volume of fluid to a
third volume of fluid on a top surface of the heat transfer element. The
latent heat is released
when the first volume of fluid condenses.
[0005] In another embodiment, an apparatus includes a housing that has at
least an inlet
and an outlet. The housing is configured to receive a volume of fluid via the
inlet. The
volume of fluid is in a substantially liquid state and at least a portion of
the volume of fluid
includes a dissolved impurity. The apparatus also includes a heat-transfer
element coupled to
an interior volume of the housing. The heat-transfer element includes a
surface, at least a
portion of which is disposed at an angle with respect to a horizontal plane.
The volume of
fluid includes a surface parallel to the horizontal plane. The apparatus
further includes a
compression component configured to compress at least a portion of fluid
boiled from the
volume of fluid.
[0006] In yet another embodiment, a method includes receiving a signal from a
sensor
disposed within a housing. The housing includes a boiler portion and a
condenser portion.
At least a portion of the boiler portion and at least a portion of the
condenser portion are
defined by a heat-transfer element coupled to an interior portion of the
housing. The method
also includes modifying an angle of the heat-transfer element relative to a
horizontal plane in
response to the signal such that at least one of a heat-transfer rate
associated with the heat-
transfer element or a flow-rate of a fluid changing phase within the housing
is modified.
Brief Description of the Drawings
[0007] FIG. 1 is a schematic block diagram that illustrates a distillation
system,
according to an embodiment of the invention.
[0008] FIG. 2 is a schematic illustration of a distillation system configured
to separate
water from salt-water, according to an embodiment of the invention.
[0009] FIG. 3 illustrates a steam saturation table that can be used to
determine an
operating point of at least portion of a distillation system, according to an
embodiment of the
invention.
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[0010] FIG. 4 is a schematic diagram that illustrates a characterization curve
associated
with a compression component, according to an embodiment of the invention.
[0011] FIG. 5 is a flowchart that illustrates a method for separating a
portion of fluid
from a volume of fluid, according to an embodiment of the invention.
[0012] FIG. 6A is a exploded perspective view of several components of a
distillation
system, according to an embodiment of the invention.
[0013] FIG. 6B is a perspective view of a heat-transfer element of FIG. 6A
without salt-
water, according to an embodiment of the invention.
[0014] FIG. 6C is a perspective view of a heat-transfer element of FIG. 6A
with salt-
water, according to an embodiment of the invention.
[0015] FIG. 6D is a perspective, transparent view of a distribution component,
according
to an embodiment of the invention.
[0016] FIG. 7A is a schematic diagram that illustrates a distillation system,
according to
an embodiment of the invention.
[0017] FIG. 7B is a schematic diagram of a portion of the distillation system
shown in
FIG. 7A, according to an embodiment of the invention.
[0018] FIG. 8 is a schematic diagram of a compression component, according to
an
embodiment of the invention.
[0019] FIG. 9 is a schematic diagram of a heat-transfer element, according to
an
embodiment of the invention.
[0020] FIG. l0A is a schematic block diagram of a side cross-sectional view of
a
distillation system that has a substantially conical heat-transfer element,
according to an
embodiment of the invention.
[0021] FIG. l OB is a schematic block diagram of a top partial cut-away view
of the
distillation system shown in FIG. 10A, according to an embodiment of the
invention.
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[0022] FIG. 11 is a schematic block diagram of a distillation system that
includes a
control unit, according to an embodiment of the invention.
[0023] FIG. 12 is a flowchart that illustrates a method for modifying an angle
of a heat-
transfer element of a distillation system, according to an embodiment of the
invention.
[0024] FIG. 13 is a flowchart that illustrates a method for initiating a
distillation system,
according to an embodiment of the invention.
Detailed Description
[0025] FIG. 1 is a schematic block diagram that illustrates a distillation
system 100,
according to an embodiment of the invention. In some embodiments, the
distillation system
can also be referred to as a distillation unit. The distillation system 100 is
configured to re-
use energy to efficiently separate a substance from a mixture of two or more
substances.
Specifically, energy that is released and/or added to the system during the
separation process
is utilized continuously to promote further separation in a cyclical fashion.
In some
embodiments, the distillation system can be a high efficiency distillation
system that can
have different portions that operate at different temperatures (e.g., at low
temperature or at
high temperature) and/or different pressures (e.g., at low pressure or at high
pressure).
[0026] The distillation system 100 includes a heat-transfer element 120, a
compression
component 140, and two chambers-chamber 110 and chamber 130. The components of
the
distillation system 100 are configured to operate in a coordinated fashion to
separate a
substance from a mixture of two or more substances through phase changes of
the substance
as portions of the mixture are cycled through the distillation system 100. For
example, the
substance can be separated from the mixture through a first phase change
within chamber
110. The first phase change can be induced (e.g., caused) by energy that is
released from a
second phase change within chamber 130 and that is transferred from chamber
130 to
chamber 110 via the heat-transfer element 120. Energy can be added to at least
some
portions of the mixture by the compression component 140 as the portions cycle
through the
distillation system 100.
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[0027] In some embodiments, the first phase change can be opposite that of the
second
phase change. For example, the first phase change can be a phase change from a
liquid state
to a gaseous state and the second phase change can be a phase change from a
gaseous state to
a liquid state, and vice versa. Thus, the first phase change can be an
endothermic (e.g.,
require/consume energy) phase transition requiring, for example, a latent heat
of vaporization
while the second phase change can be an exothermic (e.g., release energy)
phase transition
releasing, for example, a latent heat of condensation.
[0028] The distillation system 100 can be configured to operate over a wide
range of
temperatures and pressures. For example, each of the chambers 110 and 130 of
the
distillation system 100 can be configured to operate at a temperature and/or a
pressure
substantially below that of a normal boiling point of a substance within a
mixture. In some
embodiments, the chambers 110 and 130 of the distillation system 100 can be
configured to
operate at or above a temperature and/or a pressure associated with a normal
boiling point of
a substance within a mixture. In some embodiments, chamber 110 and chamber 130
can be
configured to operate at temperatures and/or pressures that are separated by a
specified
interval.
[0029] As shown in FIG. 1, chamber 110 can be configured to receive via inlet
112 a
volume of a mixture that is a fluid and that has a concentration of an
impurity. The impurity
can be, for example, one or more elements, compounds, substances, or materials
included in
(e.g., ionized in, suspended in) the volume of fluid in any phase (e.g.,
solid, liquid, gas). A
portion of fluid can be boiled into a gaseous phase from the volume of fluid
within chamber
110, and moved into the compression component 140. The gaseous portion of
fluid can be
compressed by the compression component 140 and moved into chamber 130 where
the
gaseous portion of fluid can release heat 185 as the gaseous portion of fluid
condenses
against the heat-transfer element 120. The heat 185 released from the
condensing portion of
fluid can be used to further induce boiling in a volume of fluid subsequently
introduced into
chamber 110 via inlet 112 (e.g., after the gaseous portion of fluid is boiled
within chamber
110).
[0030] The portion of fluid boiled from the volume of fluid can be referred to
as a
distillate and can have a relatively low concentration of the impurity
relative to the volume of
fluid. In other words, the portion of fluid boiled from the volume of fluid
can be a
substantially purified fluid with a relatively low level of the impurity
compared with the
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original mixture. In some embodiments, the impurity concentration of the
original volume of
fluid will be increased because the portion of fluid is boiled from the volume
of fluid and has
a relatively low concentration of the impurity. In some embodiments, the
purified fluid can
be a desired product (e.g., target product) from the distillation system 100.
The volume of
fluid with the higher impurity concentration can be referred to as a by-
product and can be
removed from chamber 110 via outlet 114. In some embodiments, the by-product
can also
be a desirable distillate or a target distillate.
[0031] Once the distillation system 100 attains a steady-state operating
condition,
continuous heat transfer through a cycle of a phase change in chamber 110, and
an opposite
phase change chamber 130, can be used to produce large volumes of a distillate
efficiently
because the energy needed for the phase change to obtain the distillate from a
volume of fluid
is substantially provided by the opposite phase change. Energy needed to
operate in a
continuous mode can substantially be equal to the energy necessary to operate
the
compression component 140. In some embodiments, the distillation system 100
can include
a control system (not shown) configured to process signals associated with,
for example, the
flow of one or more fluids and/or heat transfer within the distillation system
100. More
details related to a control system within a distillation system 100 will be
discussed in
connection with FIGS. 11 and 12.
[0032] Although the distillation system 100 shown in FIG. 1 can be used to
separate a
variety of substances from a variety of mixtures (e.g., methanol from a
methanol-water
mixture, gasoline from gasoline-water mixture, water from a sap-water mixture)
in a variety
of applications (e.g., waste water treatment), the following disclosure in
connection with
embodiments of the invention will focus on separation/distillation of water
from a salt-water
compound (NaC1-Hz0) in a liquid state as a representative example. In some
embodiments,
the salt can be dissolved in the water in, for example, an ionized state.
[0033] FIG. 2 is a schematic illustration of a distillation system 200
configured to
separate water from salt-water, according to an embodiment of the invention.
In some
embodiments, the salt-water can have other impurities included in (e.g.,
dissolved in,
suspended in) the salt-water such as calcium-based compounds (e.g., calcium
chloride
(CaC1)), zirconium-based compounds, and/or magnesium-based compounds. Many of
the
phantom lines such as phantom line 232 represent movement of a fluid
associated with the
distillation system 200.
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[0034] As shown in FIG. 2, the distillation system 200 has a housing 204 that
has a boiler
portion 206 and a condenser portion 208. An incoming salt-water stream 273 can
be moved
by, for example, a pump (not shown) into a volume of salt-water 272 in the
boiler portion
206 of the housing 204 via an inlet 282. When the volume of salt-water 272 is
above a heat-
transfer element 220 in the boiler portion 206, heat is transferred to the
salt-water 272 via the
heat-transfer element 220 so that fresh steam can be boiled from the salt-
water 272 and can
be moved 232 into a compression component 240. The fresh steam can be drawn
into (e.g.,
pulled into) the compression component 240 by the compression component 240.
[0035] The fresh steam is compressed by the compression component 240 so that
a
temperature and/or a pressure of the fresh steam at the outlet 244 of the
compression
component 240 is higher than the temperature and/or the pressure of the fresh
steam at the
inlet 242 of the compression component 240. The mechanical energy of the
compression
component 240 increases the temperature and/or the pressure of the fresh steam
as it is
moved through the compression component 240. In some embodiments, the volume
of fresh
steam is reduced by as much as half when the fresh steam is compressed by the
compression
component 240.
[0036] The compressed fresh steam is moved 234 into the condenser portion 208
of the
housing 204 and contacts a bottom surface of the heat-transfer element 220 so
that the
compressed fresh steam can condense and fa11236 into a volume of fresh water
270 in a fresh
water collection portion 209 of the housing 204. The fresh water collection
portion 209 can
also be referred to as a fresh water reservoir, fresh water container, or
fresh water tank. The
fresh water 270 can be removed from the housing 204 in an outgoing fresh water
275 stream
via an outlet 284 by, for example, a pump (not shown).
[0037] As the fresh steam is boiled from the salt-water 272, a concentration
of salt in the
salt-water 272 is increased until the salt-water 272 becomes brine 274. In
some
embodiments, the brine 274 can be water saturated or nearly saturated with
salt. The brine
274 can be removed from the housing as an outgoing brine stream 277 via an
outlet 286 by,
for example, a pump (not shown). In some embodiments, the outgoing brine
stream 277 can
be removed by gravity. In some embodiments, the brine 274 can be, for example,
approximately 25% salt by weight. In some embodiments, the brine 274 can be
sold as a
product used for medicinal purposes, culinary purposes, in an oil extraction
process (not
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shown), in a heat exchange process (not shown), and/or as a reactant in
chemical process (not
shown).
[0038] Although the water boiled from the salt-water 272 and the water
condensed at the
heat-transfer element 220 are referred to as fresh steam and fresh water,
respectively, the
fresh steam and fresh water can include some impurities. However, the
concentration of
impurities (e.g., concentration based on moles, concentration based on weight)
can be
significantly lower than that in the salt-water 272. In other words, the
salinity of the fresh
water can be lower than that of the salt-water 272. Said differently, the
fresh steam and/or
the fresh water can have a salt concentration lower than a salt concentration
of the salt-water
272 before the fresh steam is boiled from the salt-water 272.
[0039] The fresh steam can be boiled from the salt-water 272 above the heat-
transfer
element 220 using almost exclusively a latent heat released from condensation
of the
compressed steam from the compression component 240. In other words, the
energy/heat
needed for the endothermic phase transition of the liquid water in the salt-
water 272 into the
fresh steam can be substantially provided by the energy/heat from the
exothermic phase
transition of the gaseous compressed steam into liquid water (e.g., condensed
fresh water
270). In some embodiments, the flow-rate of fluids (e.g., salt-water, steam,
etc.) to, from,
and/or within the housing 204 can be defined so that fresh steam is boiled
nearly entirely by
heat from condensation of the compressed steam from the compression component
240
(shown as line 234).
[0040] As shown in FIG. 2, the heat-transfer element 220 has a sloped surface
with
respect to a horizontal plane 226. In some embodiments, an angle 224 of the
heat-transfer
element 220 with respect to the horizontal plane 226 can be a few degrees
(e.g., 1 degree, 15
degrees, 45 degrees) or even a fraction of a degree. The slope of the heat-
transfer element
220 is designed to facilitate boiling of the fresh steam from the salt-water
272 by enabling
heat transfer through the heat-transfer element 220 to a shallow depth 222 of
the salt-water
272. In this embodiment, a surface of the salt-water 272 intersects the heat-
transfer element
220 at a zero-depth point 228. In some embodiments, the depth 222 of the salt-
water 272 can
be between a fraction of an inch (e.g., 0.1 inches) and several inches (e.g.,
2.2 inches, 5
inches).
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[0041] A higher percentage of heat transferred via the heat-transfer element
220 can be
directly used to cause boiling because the depth 222 of the salt-water 272
over all or a
portion of the heat-transfer element 220 is shallow. In other words, the
shallow depth 222
promotes efficient heat transfer. Specifically, the effects of the heat will
not be offset
significantly by conduction to new, cooler incoming salt-water 273 as it flows
via inlet 282
into the volume of salt-water 272 in the boiler portion 206 of the housing
204. Also, boiling
within the boiler portion 206 of the housing 204 will not be significantly
inhibited by static
pressure related to the depth 222 of the salt-water 272 when the depth 222 of
the salt-water
272 is shallow.
[0042] The heat-transfer element 220 can be constructed of a material that
facilitates
efficient heat transfer from the condenser portion 208 to the boiler portion
206 of the housing
204. Specifically, the material of the heat-transfer element 220 can be chosen
so that the
thermal conductivity of the heat-transfer element 220 is relatively high and
will not result in
undesirable, inefficient heat loss. For example, the heat-transfer element 220
can be
constructed of a pure metal and/or an alloy that can include substances such
as copper, silver,
gold, and/or aluminum. Also, the heat-transfer element 220 can be relatively
thin so that the
heat-transfer element 220 will further promote efficient heat transfer at a
desirable level. In
some embodiments, for example, the heat-transfer element can be a fraction of
an inch (e.g.,
1/8 of an inch, 1/32 of an inch). In some embodiments, the heat-transfer
element 220 can be
or can include a polymer-based material.
[0043] In this embodiment, the heat-transfer element 220 is entirely disposed
within the
housing 204 and defines at least a portion of the boiler portion 206 and at
least a portion of
the condenser portion 208 of the distillation system 200. For example, the top
surface of the
heat-transfer element 220 defines a bottom boundary of the boiler portion 206,
and the
bottom surface of the heat-transfer element 220 defines a top boundary of the
condenser
portion 208.
[0044] In some embodiments, the shape of the heat-transfer element 220 can be
modified
so that compressed fresh steam impinging on the bottom surface of the heat-
transfer element
220 will be channeled to certain locations on the heat-transfer element 220.
In some
embodiments, the heat transfer-element 220 can have different (e.g., varying)
thicknesses
and/or shapes over at different portions of the heat-transfer element 220 so
that the different
portions will have different heat-transfer characteristics. The heat-transfer
characteristics can
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vary according to temperature and/or pressure gradients within the boiler
portion 206 and/or
the condenser portion 208. Various shapes and types of heat transfer-elements
are discussed
in connection with subsequent figures.
[0045] In some embodiments, the distillation system 200 can have a
distribution
component (not shown) to facilitate distribution of compressed steam from the
compression
component 240 (shown as line 234) against the bottom surface of the heat-
transfer element
220. For example, the distribution component can be configured to cause the
compressed
steam to be substantially evenly distributed along the bottom surface of the
heat-transfer
element 220 or distributed in a particular pattern against the heat-transfer
element 220. In
some embodiments, the distribution component can be configured to distribute
the
compressed steam against the bottom surface of the heat-transfer element 220
based on
and/or to create a specified pressure gradient and/or temperature gradient
within the boiler
portion 206 and/or the condenser portion 208.
[0046] In some embodiments, the distribution component can be configured to
force the
compressed steam to impinge on the bottom surface of the heat-transfer element
220 to
facilitate condensation. For example, the compressed steam can be forced onto
the bottom
surface of the heat-transfer element 220 to move substances off of the bottom
surface heat-
transfer element 220 that may inhibit condensation (e.g., precipitates,
condensed fresh water).
More details related to a distribution component are discussed in connection
with FIGS. 6A
and 6D.
[0047] The components of the distillation system 200 can be constructed of
various
materials such as, for example, metals, rubbers, and/or polymer-based
materials (e.g., acrylic,
polyethylene, fiberglass). For example, the housing 204 of the distillation
system 200 can be
constructed of a plastic material such as Teflon or polystyrene, and the
piping of the
distillation system 200 can be a poly-vinyl chloride (PVC)-based material.
[0048] As shown in FIG. 2, the outgoing brine stream 277 from outlet 286, the
outgoing
fresh water stream 275, and the incoming salt-water stream 273 are configured
to exchange
heat in a heat-exchanger 260. The heat-exchanger 260 is configured to exchange
heat from
the outgoing brine stream 277 and the outgoing fresh water stream 275 with the
incoming
salt-water stream 273 to preheat the incoming salt-water stream 273. By
transferring heat to
the incoming salt-water stream 273 before it enters the boiler portion 206,
the temperature of
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the incoming salt-water stream 273 can be at or substantially close to the
boiling point of
water at the operating pressure of the boiler portion 206 of the distillation
system 200. Thus,
only a relatively small quantity of heat will be required to cause the salt-
water 272 to boil
(e.g., a latent heat of condensation). The small quantity of heat can be added
by the
compression component 240 to the compressed steam, which eventually releases
the heat to
the salt-water 272 to cause it to boil when the compressed steam condenses at
the heat-
transfer element 220. It logically follows that the energy used by the
compression
component 240 can be reduced when the incoming salt-water stream 273 (which
feeds into
the salt-water 272) is closer to a desired boiling point (e.g., a desirable
temperature and/or
pressure for boiling).
[0049] In some embodiments, the heat exchanger 260 can be configured to use
energy
from outside of the distillation system 200 to preheat the incoming salt-water
stream 273.
For example, the heat exchanger 260 can be configured to use solar energy (not
shown) or
energy from an output (e.g., a waste stream, a low-grade waste heat) from a
separate process
(not shown) to preheat the incoming salt-water stream 273 to a desired
temperature at a
specified operating pressure of the boiler portion 206 of the housing 204. In
some
embodiments, the heat exchanger 260 can be, for example, a shell and tube heat
exchanger, a
plate heat exchanger, and/or a regenerative heat exchanger.
[0050] In some embodiments, one or more of the components of the distillation
system
200, in addition to, or instead of the heat exchanger 260, can be configured
to use energy
scavenged from an environment surrounding the distillation system 200. For
example, one
or more pumps (not shown), control units (not shown), and/or sensors (not
shown) associated
with the operation of the distillation system 200 can be powered by wind
energy, solar
energy, and/or energy from an output (e.g., waste stream) from a separate
process (not
shown). One or more of the components of the distillation system 200 can be
powered by an
energy storage device such as a battery and/or a fuel cell.
[0051] The distillation system 200 can be configured to produce fresh water
from salt-
water 272 over a wide range of temperatures and pressures. In this embodiment,
one or more
portions of the distillation system 200 (e.g., the boiler portion 206, the
condenser portion
208) can be configured to operate at a temperature and/or a pressure
substantially below that
associated with a normal boiling point of water. For example, the boiler
portion 206 can be
configured to operate at a specified pressure substantially below a standard
atmospheric
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pressure (e.g., 1 atmosphere). In some embodiments, one or more portions of
the distillation
system 200 (e.g., the boiler portion 206, the condenser portion 208) can be
configured to
operate at a temperature and/or a pressure at or above that associated with a
normal boiling
point of water.
[0052] The distillation system 200 can be configured so that the boiler
portion 206 and
the condenser portion 208 operate at a temperature separated by a specified
interval and/or
operate at a pressure separated by a specified interval. For example, the
boiler portion 206
and the condenser portion 208 can be configured to operate at temperatures
separated by a
few degrees (e.g., a few degrees Fahrenheit (F), a few degrees Kelvin (K)). In
some
embodiments, the boiler portion 206 and the condenser portion 208 can be
configured to
operate at pressures separated by a fraction of a pressure unit (e.g., a
pounds per square inch
absolute (psia) unit, a millimeters of mercury (mmHg) unit). The energy
resulting in the
difference in pressure and/or the difference in temperature between the boiler
portion 206
and the condenser portion 208 can be provided by mechanical energy from the
compression
component 240.
[0053] FIG. 3 illustrates a steam saturation table that can be used to
determine an
operating point of at least a portion of a distillation system, according to
an embodiment of
the invention. The operating point can be defined by a combination of, for
example, an
operating pressure, an operating temperature, an operating humidity, and so
forth. The
distillation system can be, for example, distillation system 200 shown in FIG.
2. The
respective operating points of the boiler portion 206 and the condenser
portion 208 can be
selected by: (1) selecting the boiler portion 206 operating point using the
saturation table
shown in FIG. 3, and (2) calculating the condenser portion 208 operating point
based on the
boiler portion 206 operating point. The operating point of the condenser
portion 208 can be
calculated from the boiler portion 206 operating point based on several
factors, including, for
example, the heat transfer characteristics of the heat-transfer element 220
and heat of
vaporization changes due to impurities.
[0054] For example, at an operating point of 0.5 psia and 78 F (shown at
306), 1096.4
British Thermal Units (BTUs) are required to cause a phase change of a pound
(lb) of liquid
water at the boiler portion 206. If the heat-transfer efficiency at the heat-
transfer element 220
is 99.91 % and impurities within the salt-water 272 increase the heat of
vaporization by
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0.14%, the heat required at the condenser side of the heat-transfer element
220 to cause
vaporization is 1098.9 BTU/lb. Based on the saturation table, the operating
point at the
condenser portion 208 should be 0.6 psia and 85 F (shown at 308) to meet this
heat
requirement. The condenser portion 206 is operated at a slightly higher steady-
state
temperature and pressure so that heat from condensation in the condenser
potion 208 will be
transferred to the boiler portion 206 via the heat-transfer element 220. In
some
embodiments, a reduction in a thickness of the heat-transfer element 220 can
increase the
efficiency of the heat-transfer element 220.
[0055] Referring back to FIG. 2, in some embodiments, a difference in
temperature
and/or pressure of the operating points of the boiler portion 206 and the
condenser portion
208 can substantially be produced by the compression component 240. In other
words,
energy can be added to fluids (e.g., fresh steam) moving from the boiler
portion 206 to the
condenser portion 208 to maintain the different conditions of the operating
points. In some
embodiments, the boiler portion 206 of the distillation system 200 can operate
at high
temperature and/or pressure and the condenser portion 208 of the distillation
system 200 can
operate at low temperature and/or pressure, and vice versa.
[0056] If the boiler portion 206 is configured to operate at a low pressure
that is
substantially below a standard atmospheric pressure, the low pressure can be
maintained/generated by the weight of the incoming salt-water 273 stream.
Although not
shown in FIG. 2, the distillation system 200 can be configured so that the
incoming salt-
water 273 is a column of incoming salt-water with a weight that is suspended
below the
boiler portion 206 by the pressure in the boiler portion 206. Moreover, the
height of the
column of the incoming salt-water 273 stream can be defined to create a
specified low
pressure within the boiler portion 206. Other streams of the distillation unit
200 such as the
outgoing brine 277 stream can be similarly configured to assist in
maintaining/defining a low
pressure within the boiler portion 206. The weight of the outgoing fresh water
275 can be
used to maintain/define a specified pressure in the condenser portion 208.
[0057] In some embodiments, the distillation system 200 can be operated at a
specified
temperature and/or pressure to substantially prevent a particular undesirable
side-effect. In
some embodiments, the distillation system 200 can be configured operate at a
specified
temperature and/or at a specified pressure to prevent precipitation and/or
dissolution of
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different compounds (e.g., magnesium-based compounds). For example, the
distillation
system 200 can be configured to operate at a temperature below 185 F so that
impurities
such as calcium-based compounds that may be in the salt-water 272 will not
precipitate. In
some embodiments, the boiler portion 206, for example, can be configured to
operate above a
specified temperature so that particular impurities (e.g., microbes, bacteria)
will be destroyed.
Also, insulation of the distillation system 200 from, for example, an ambient
environment
can be reduced by operating at a lower temperature than if the distillation
system 200 were
operating at a high temperature.
[0058] In some embodiments, condensation of fresh steam at the bottom surface
of the
heat-transfer element 220 can assist in maintaining the low pressure
environment at, for
example, a condenser portion 208 of the distillation system 200. In other
words, the collapse
of the voluminous compressed steam into a liquid when the compressed steam
condenses can
create a negative pressure environment that can decrease the pressure of the
condenser
portion 208 of the distillation system 200.
[0059] In some embodiments, as the outgoing brine stream 277 is pumped out of
the
boiler portion 206 of the housing 204, the pressure within the boiler portion
206 of the
housing 204 can be decreased. In some embodiments, the flow-rate of the brine
stream 277
can be adjusted to assist in maintaining a low pressure operating environment
within the
boiler portion 206 of the housing 204. In some embodiments, the distillation
system 200 can
continuously operate at a steady-state after a start-up sequence. In some
embodiments, the
energy required during steady-state is substantially the energy required to
operate the
compression component 240. More details related to a start-up sequence are
discussed in
connection with FIG. 13.
[0060] In some embodiments, the compression component 240 can have a
monotonically changing pressure differential versus flow-rate characteristic
such as that
shown in FIG. 4. FIG. 4 is a schematic diagram that illustrates a
characterization curve 420
associated with a compression component, according to an embodiment of the
invention. As
shown in FIG. 4, a pressure differential (AP) (shown on the y-axis) of the
compression
component monotonically decreases as a flow-rate (shown in the x-axis) through
the
compression component increases. The pressure differential is a difference in
pressure
between an outlet of the compression component and an inlet of the compression
component.
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The monotonically changing characteristic of the compression component
promotes stability
of a distillation system (e.g., distillation system 100 shown in FIG. 1)
especially when the
distillation system is operating at low temperatures and/or at low pressures.
[0061] In some scenarios, a compression component that does not have a
monotonically
changing pressure differential versus flow-rate characteristic could oscillate
between flow-
rates in an unstable fashion when a pressure in a housing of the distillation
system were to,
for example, unexpectedly drop. This type of oscillation could cause the
distillation system
to fail to produce a distillate or to produce an undesirable distillate
because a continuous
phase change energy would not be available due to the inconsistent flow.
[0062] In some embodiments, the compression component 240 can include one or
more
compressors (e.g., staged compressors) and/or one or more valving components
(not shown).
The compression component 240 can be, for example, a centrifugal compressor, a
hydraulic
compressor, a diagonal or mixed-flow compressor, an axial-flow compressor, a
reciprocating
compressor, a rotary screw compressor, a scroll compressor, a lobe type
compressor (e.g.,
roots blower) and/or a diaphragm compressor. In some embodiments, the
compression
component 240 can include a system of coordinated valves such as that shown in
and
described in connection with FIG. 8.
[0063] In some embodiments, the compression component 240 can be disposed
within
the housing 204 of the distillation system 200. In some embodiments, by
disposing the
compression component 240 in the housing 204, issues associated with, for
example, small
leaks within the compression component 240 can be mitigated or completely
avoided. For
example, the compression component 240 can include a hydraulic motor disposed
within the
housing 204. In some embodiments, heat generated by mechanical portions of the
compression component 240 can be transferred to the salt-water 272 to further
induce boiling
at the boiler portion 206 of the housing 204. In some embodiments, a motor
disposed outside
of the housing 204 can be magnetically coupled to a propeller(s) or fan
blade(s) that is
disposed within the housing 204 and that is configured to compress fresh
steam.
[0064] In some embodiments, the compression component 240 can be disposed
below
the heat-transfer element 220 and/or the housing 204. In some embodiments, the
distillation
system 200 can have multiple compression components, multiple incoming streams
of each
type of incoming stream (e.g., multiple incoming salt-water streams), multiple
outgoing
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streams of each type of outgoing stream (e.g., multiple outgoing brine
streams), multiple
boiler and/or condenser portions, and/or multiple heat-transfer elements. In
some
embodiments, the distillation system 200 can have multiple stages. For
example, an outgoing
stream from a first distillation system can be an incoming stream on a second
distillation
system.
[0065] In some embodiments, the distillation system 200 can have a degassing
system
(not shown) configured to degas, for example, the incoming salt-water stream
273 so that
boiling above the heat-transfer element 220 will not be undesirably disrupted
if a gas is
released from the salt-water. In some embodiments, the degassing system can be
configured
to degas the incoming salt-water 273 before the salt-water is received at the
heat exchanger
260. In some embodiments, the degassing system can be configured to degas the
incoming
salt-water 273 after the heat-exchanger 260. In some embodiments, at least a
portion of the
degassing system can be disposed within the housing 204.
[0066] In some embodiments, the distillation system 200 can include, for
example, a
sonic transducer (not shown) configured to facilitate boiling above the heat-
transfer element
220. In some embodiments, the sonic transducer can be an ultrasonic
transducer. The sonic
transducer can enhance fracturing of the salt-water, for example, to
facilitate a change from a
liquid state to a vapor state. In some embodiments, the sonic transducer can
be further used
to degas the salt-water 272. In some embodiments, the ultrasonic transducer
can be disposed
within the boiler portion 206 of the housing 204.
[0067] FIG. 5 is a flowchart that illustrates a method for separating a
portion of fluid
from a volume of fluid, according to an embodiment of the invention. The
flowchart
illustrates that a volume of fluid with an impurity concentration is received
at a housing of a
distillation system at 500. The volume of fluid can be a volume of water and
the impurity
concentration can be, for example, salt. In some embodiments, the volume of
fluid can
include multiples types of impurities (e.g., calcium-based impurities,
magnesium-based
impurities).
[0068] The volume of fluid is received at a top surface of a heat-transfer
element within a
boiler portion of the housing at 510. The volume of fluid can be pumped from,
for example,
a body of salt-water and received via an inlet of the housing. The top surface
of the heat-
transfer element can define at least a portion of the boiler portion of the
housing.
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[0069] A portion of fluid is boiled from the volume of fluid at 520. If the
volume of fluid
is a volume of salt-water, the portion of fluid can be fresh water boiled from
the salt-water in
a gaseous state as steam.
[0070] The volume of fluid is received at a brine collection portion of the
distillation
system at 530 after the portion of fluid is boiled from the volume of fluid.
In some
embodiments, the volume of fluid can have a different impurity concentration
after the
portion of fluid is boiled from the volume of fluid.
[0071] The portion of fluid is compressed and moved from the boiler portion
into a
condenser portion of the housing at 540. The portion of fluid can be
compressed and moved
by a compression component coupled to the housing.
[0072] The portion of fluid is condensed at a bottom surface of the heat-
transfer element
at 550. The portion of fluid can be condensed as the portion of fluid is
impinged against the
bottom surface of the heat-transfer element. The bottom surface of the heat-
transfer element
can define at least a portion of the condenser portion of the housing.
[0073] The heat released at the bottom surface of the heat-transfer element is
transferred
from the portion of fluid to the boiler portion at 560. In some embodiments,
all or
substantially all of the heat released at the bottom surface of the heat-
transfer element can be
transferred via the heat-transfer element.
[0074] The condensed portion of fluid is received at a fresh water collection
portion of
the distillation system at 570. In some embodiments, the condensed portion of
fluid can be
pumped from the fresh water collection portion of the distillation system. In
some
embodiments, the fresh water collection portion of the distillation system can
be disposed
within the housing.
[0075] FIG. 6A is a an exploded perspective view of several components of a
distillation
system 600, according to an embodiment of the invention. The distillation
system 600 has a
top portion 610 of a housing 680 that defines at least a portion of a boiler,
a heat-transfer
element 620, a distribution component 630, and a fresh water collection
reservoir 640. In
this embodiment, incoming salt-water 631 is received within the distillation
system 600 via
inlet 674. The salt-water flows along a top portion 622 of the heat-transfer
element 620 in
the direction of arrow 632 and fresh steam is boiled from the salt-water as
shown by arrow
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634. In some embodiments, a slope of the heat-transfer element 620 is
substantially less then
1 degree with respect to a horizontal plane.
[0076] Perspective views of the heat-transfer element 620 are shown in FIGS.
6B and
6C. FIG. 6B illustrates the heat-transfer element 620 (also shown in FIG. 6A)
without salt-
water and FIG. 6C illustrates the heat-transfer element 620 (also shown in
FIG. 6A) with
salt-water 664. The salt-water 664, which has a concentration that increases
as it passes over
a corrugated portion 666 of the heat-transfer element 620 until it reaches a
brine
concentration, exits out of opening 626. The salt-water 664 intersects at a
zero-depth point
between nearly every furrow and ridge of the corrugated portion 666. At the
deepest point of
each furrow, a depth of the salt-water 664 can be, for example, a few inches
or less. In this
embodiment, the incoming salt-water 631 (shown in FIG. 6A) is pumped into a
reservoir 668
of the heat-transfer element 620, so that the salt-water 664 can be evenly
distributed over the
corrugated portion 666 of the heat-transfer element 620. The reservoir 668 can
be referred to
as a distribution reservoir.
[0077] Referring back to FIG. 6A, the brine 636 exits out of the housing 680
of the
distillation system 600 via outlet 676. After the steam 634 is compressed, the
compressed
steam 638 is injected towards a bottom portion 624 of the heat-transfer
element 620 via slots
652 into a middle portion 650 of the housing 680. The compressed steam 638 is
distributed
into the slots 652 using the distribution manifold 690 shown in FIG. 6D. As
shown in FIG.
6D, the distribution manifold 690 has an inlet 694, and outlet slots 696 that
correspond to
slots 652 (shown in FIG. 6A). The compressed steam 638 is distributed to the
slots 652 via
the manifold system 692 of the distribution manifold 690. In some embodiments,
the
distribution manifold 690 can be referred to as a distribution component.
[0078] Referring back to FIG. 6A, the compressed steam 638 is further directed
by the
channeling system 644 of distribution component 630. In some embodiments, a
horizontal
plane 646 of the distribution component 646 can have multiple openings (e.g.,
orifices) to
direct the compressed steam 638 towards the bottom surface 624 of the heat-
transfer element
620 (in the direction of arrow 648) after the compressed steam 638 is injected
into the
housing 680. After the compressed steam 638 condenses at the bottom portion
624 of the
heat-transfer element 620, the condensed fresh water 662 is collected in
reservoir 660.
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[0079] FIG. 7A is a schematic diagram that illustrates a distillation system
700,
according to an embodiment of the invention. The distillation system 700 has a
housing 710
that includes a heat exchanger 760, compression component 740, and a heat-
transfer element
720. The housing 710 has a portion that functions as a boiler 712 and a
portion that functions
as a condenser 714.
[0080] As shown in FIG. 7A, salt-water 722 flows down (e.g., pulled by
gravity) the
heat-transfer element 720 from a salt-water reservoir 754 to brine 774 in a
brine reservoir
776. As the salt-water 722 flows down the heat-transfer element 720, fresh
water is boiled
from the salt-water 722 as fresh steam and moved 724 into the compression
component 740
(shown as line 724). The fresh steam is compressed into compressed steam
(e.g., compressed
fresh steam) at the compression component 740 and moved towards a bottom
surface 728 of
the heat-transfer element 720 where the compressed steam condenses (shown as
line 726).
Heat released from the phase transition at the bottom surface 728 of the heat-
transfer element
720 is transferred via the heat-transfer element 720 to the flowing salt-water
722 to cause
fresh steam to boil from the flowing salt-water 722. In some embodiments, the
distillation
system 700 can have a distribution component (not shown) configured to
facilitate
distribution of compressed steam against the bottom surface 728 of the heat-
transfer element
720. After the compressed steam condenses into fresh water, the fresh water
770 is collected
in a fresh water reservoir 778.
[0081] FIG. 7B is a schematic diagram of a portion of the distillation system
700 shown
in FIG. 7A, according to an embodiment of the invention. As shown in FIG. 7B,
a surface of
the salt-water 722 flowing down the heat-transfer element 720 is substantially
parallel to the
slope of the heat-transfer element 720. Accordingly, the salt-water 722 can
have a shallow
depth 782 over substantially the entire length of the heat-transfer element
720. In some
embodiments, the flow-rate of the salt-water 722 and depth 782 of the salt-
water 722 can be
determined by a level of salt-water in the salt-water reservoir 754 and/or a
height of an
opening 784 from the salt-water reservoir 754. In some embodiments, the flow-
rate of the
salt-water 722 can be controlled by the shape and/or slope of the heat-
transfer element 720.
[0082] In some embodiments, the distillation system 700 (e.g., heat-transfer
element 720,
boiler 712, etc.) can be configured so that the vapor pressure of the salt-
water 722 at points
732 and 736 (points at opposite ends of the heat-transfer element 720) during
operation of the
distillation system 700 can be substantially the same. Also, the flow-rate of
the salt-water
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722 over the heat-transfer element can be defined so that the static pressures
at points 734
and 738 can be substantially the same and approximately equal to the pressure
within the
boiler 712. In other words, the depth 782 of the salt-water 722 can be defined
so that that
static pressure from the depth 782 of the salt-water 722 will be negligible,
thus promoting
boiling above a top surface of the heat-transfer element 720. For example, if
the boiler 712 is
configured to operate at a specified pressure substantially below a standard
atmospheric
pressure, the vapor pressure at points 732 and 736 can be substantially equal
to the specified
pressure, and the pressure at points 734 and 738 can be substantially the same
as the
specified pressure.
[0083] Referring back to FIG. 7A, a recycling pump 780 is configured to
recycle at least
a portion of the brine 774 by pumping the portion from the brine reservoir 776
into the salt-
water reservoir 754. The portion of the brine 774 can then be subjected to the
boiling process
where additional fresh water can be extracted from the brine 774. Fresh water
can be more
effectively extracted by recycling some of the brine 774 especially if the
brine 774 is not
saturated with salt. In other words, a higher percentage of fresh water can be
removed from
the salt-water 722 than without the recycling.
[0084] In some embodiments, the recycling of the brine 774 using the recycling
pump
780 can be performed in response to a signal indicating that additional fresh
water can be
extracted from the brine 776. For example, a sensor (not shown) and an
associated control
module (not shown) can be configured to activate and/or control the recycling
pump 780
when it is determined that the salt concentration of the brine 774 is below a
specified
threshold value.
[0085] FIG. 8 is a schematic diagram of a compression component 840, according
to an
embodiment of the invention. The compression component 840 is configured to
use heat
from a waste stream 850 to compress fresh steam in a chamber 846 before moving
the fresh
steam towards a heat-transfer element (not shown) where energy from the fresh
steam can be
transferred upon condensation. The compression component 840 has an inlet
valve 842 and
an outlet valve 844 that are configured to operate in a coordinated fashion.
The inlet valve
842 is opened while the outlet valve 844 is closed to allow fresh steam to
enter and fill the
chamber 846 of the compression component 840. After a specified period of
time, the inlet
valve 842 is closed and the fresh steam in the chamber 846 is heated to
increase the
temperature and/or the pressure of the fresh steam. After a specified period
of time, the
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outlet valve 844 is opened and the steam is released to, for example, a
condenser (not shown)
of a distillation system.
[0086] FIG. 9 is a schematic diagram of a heat-transfer element 990, according
to an
embodiment of the invention. The heat-transfer element 990 has several steps
992. The
steps 992 of the heat-transfer element 990 can be configured to modify or
define the flow-
rate of salt-water 980 over the heat-transfer element 990 and/or heat-transfer
characteristics
of the heat-transfer element 990.
[0087] FIG. l0A is a schematic block diagram of a side cross-sectional view of
a
distillation system 1000 that has a substantially conical heat-transfer
element 1020, according
to an embodiment of the invention. The conical heat-transfer element 1020 has
a top surface
1048 above which salt-water 1022 from a salt-water reservoir 1054 can be
boiled. The fresh
steam can be moved (as shown by line 1094) through an opening 1046 at a top
portion of the
conical heat-transfer element 1020 towards a bottom surface 1049 of conical
heat-transfer
heat element 1020 where the fresh steam can be condensed. The fresh steam can
be moved
by blades of a propeller 1026 driven by a motor 1090 disposed within a housing
1010 of the
distillation system 1000. After the fresh steam is condensed into condensed
water, the
condensed water can be collected at (or below) the base 1044 of the conical
heat-transfer
element 1020 in a fresh water reservoir 1070. In some embodiments, the heat-
transfer
element 1020 can be configured similar to the heat-transfer element 990
illustrated in FIG. 9.
[0088] As shown in FIG. 10A, the propeller 1026 (which is a portion of a
compression
component 1040) rotates about a shaft 1024 (e.g., axis) extending from the
opening 1046 to
the base 1044. The shaft 1024 is secured to the housing 1010 by two sets of
bearings 1078
and 1076. Because the components of the compression component 1040 are
entirely
disposed within the housing 1010, seals and other components to prevent
leakage are not
needed in some embodiments. Also, much of the heat generated by the
compression
component 1040 can be used to pressurize and/or increase the temperature of
fresh steam as
it is moved (shown by line 1094) from outside of the conical heat-transfer
element 1020 to a
portion within the conical heat-transfer element 1020.
[0089] Also as shown in FIG. 10A, a heat exchanger 1060 can be used to
transfer heat
from the fresh water reservoir to incoming salt-water (not shown) being moved
to the salt-
water reservoir 1054. In some embodiments, the heat-exchanger 1060 can be
configured to
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utilize energy from outside of the distillation system 1000 (e.g., solar
energy). High
concentration salt-water and/or brine are collected in a brine reservoir 1074.
[0090] FIG. l OB is a schematic block diagram of a top partial cut-away view
of the
distillation system 1000 shown in FIG. 10A, according to an embodiment of the
invention.
As shown in FIG. l OB, the heat-transfer element 1020 is a substantially
circular heat-transfer
element 1020. In some embodiments, the heat-transfer element 1020 can be semi-
circular or
a different shape (e.g., pentagonal, octagonal). In some embodiments, the
housing 1010 can
also have a different shape than that shown in FIG. lOB (e.g., round,
circular, triangular).
[0091] FIG. 11 is a schematic block diagram of a distillation system 1100 that
includes a
control unit 1110, according to an embodiment of the invention. The
distillation system 1100
has a heat-transfer element 1120 defining at least a portion of a boiler 1140
and at least a
portion of a condenser 1142. The distillation system 1100 also has a
compression component
1130, an actuator 1150 coupled to the heat-transfer element 1120, an outlet
valve 1162
coupled to an outlet 1172, and an inlet valve 1164 coupled to an inlet 1174.
The outlet 1172
is an outlet from a housing 1104 and the inlet 1174 is an inlet into the
housing 1104. The
outlet valve 1162 and the inlet valve 1164 can each have an actuator
configured to modify
flow.
[0092] The control unit 1110 is configured to control (e.g., change, modify,
trigger a
change) one or more portions or functions of the distillation system 1100 in
response to a
signal from a sensor 1160. The control unit 1110 can be configured to control
the distillation
system before, after, or during operation of the distillation system 1100. The
control unit
1110 can be configured control the distillation system 1100 based a control
module 1112 of
the control unit 1110. For example, the control unit 1110 can be configured to
implement a
start-up sequence. The control module 1112 can include one or more hardware
modules
(e.g., firmware, digital signal processor) and/or one or more software modules
(e.g.,
instructions, software programs) that can be based on one or more instructions
(e.g.,
computer programs, algorithms). The control module 1112 can include one or
more memory
portions (not shown) and/or one or more processing portions (not shown).
[0093] The control unit 1110 can be configured to control at least a portion
of the
distillation system 1100 based on a control algorithm (e.g., control
procedure) such as a
feedback algorithm and/or a feed-forward algorithm. The control algorithm can
be based on
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any combination of proportional control, derivative control, and/or integral
control. The
control unit 1110 can be configured to control at least a portion of the
distillation system
1100 based on historical data associated with the distillation system 1100.
The historical
data can be stored in response to an instruction from the control unit 1110
and can be stored
in a database (not shown) that can be accessed by the control unit 1110.
[0094] The sensor 1160 can include one or more of, for example, a temperature
sensor, a
pressure sensor, a humidity sensor, a flow-rate sensor, an electromagnetic
radiation sensor,
and so forth. Although one sensor 1160 is shown in this embodiment, in some
embodiments,
a distillation system 1100 can have many sensors (not shown) in various
portions of the
distillation system 1100. For example, a sensor (not shown) can be coupled to
the heat-
transfer element 1120, a sensor (not shown) can be disposed within the
condenser 1142,
and/or a sensor (not shown) can be disposed within the compression component
1130. In
some embodiments, at least a portion of the sensor 1160 (or another sensor)
can be disposed
outside of the housing 1104 of the distillation system.
[0095] The control unit 1110, for example, can be configured to modify an
angle 1112 of
the heat-transfer element 1120 with respect to a horizontal plane 1118 in
response to a signal
from the sensor 1160. The control unit 1110 can change the slope of the heat-
transfer
element 1120 by sending a signal that triggers movement of the actuator 1150
coupled to the
heat-transfer element 1120. The signal can be sent from the control unit 1110
when one or
more conditions are satisfied (e.g., threshold condition is satisfied). In
some embodiments, a
flow-rate of fluid 1114 can be modified when the angle 1112 is changed. In
some
embodiments, the control unit 1110 can be configured to modify a rate of heat-
transfer rate of
the heat-transfer element 1120 based on a signal from the sensor 1160. The
heat-transfer rate
can be calculated at the control unit 1110 based on one or more signals from
sensor 1160
(and/or another sensor) of the distillation system 1100.
[0096] The control unit 1110 can be configured to modify a flow-rate of the
outlet 1172
and/or a flow-rate of the inlet 1174 based on a signal from the sensor 1160
(or another sensor
(not shown)) by changing valve 1162 and/or valve 1164, respectively. For
example, if the
rate of boiling, pressure, and/or temperature of a fluid 1114 above the heat-
transfer element
1120 is below a threshold value as determined by the control unit 1110 based
on a signal
from the sensor 1160, the control unit 1110 can change the flow-rate (shown as
line 1132)
via outlet 1172 by moving a portion of valve 1162. Likewise, if the rate of
boiling, pressure,
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and/or temperature of a fluid 1114 above the heat-transfer element 1120
satisfies a condition
as determined by the control unit 1110 based on a signal from the sensor 1160,
the control
unit 1110 can change the flow-rate (shown as line 1134) via inlet 1174 by
moving a portion
of valve 1164.
[0097] In some embodiments, the control unit 1130 can be configured to modify
the
output and/or input (e.g., input temperature, input pressure, output
temperature, output
pressure) of the compression component 1130 in response to a signal from the
sensor 1160.
For example, the control unit 1130 can be configured to modify a speed of a
motor (not
shown) of the compression component 1130 when a condensation rate, a pressure,
and/or a
temperature below the heat-transfer element 1120 satisfies a threshold
condition. In some
embodiments, the control unit 1130 can be configured to modify the output
and/or input of
the compression component 1130 when a fresh water production rate and/or
compressed
steam production rate are below a specified limit.
[0098] In some embodiments, the control unit 1110 can be configured to modify
a flow-
rate of a fluid into the housing 1104 from a reservoir (not shown) disposed
outside of the
housing 1104. In some embodiments, the control unit 1110 can be configured to
modify a
flow-rate, a temperature, and/or a pressure of a fluid within the housing 1104
from a
reservoir (not shown) disposed within the housing 1104. In some embodiments,
the control
unit 1110 can be configured to modify a flow-rate, a temperature, and/or a
pressure of a
waste product (e.g., brine) within and/or outside of the housing 1104.
[0099] The control unit 1110, in some embodiments, can be configured to modify
a
portion of the distillation system 1100 (e.g., slope of heat-transfer element
1120, flow-rate of
a fluid) so that a temperature within the boiler 1140 (e.g., at or above the
heat-transfer
element 1120) and a temperature within the condenser 1142 (e.g., at or below
the heat-
transfer element 1120) are separated by a specified interval. In some
embodiments, the
control unit 1110 can be configured to modify a portion of the distillation
system 1100 (e.g.,
slope of heat-transfer element 1120, flow-rate of a fluid) so that a pressure
within the boiler
1140 and a pressure within the condenser 1142 are separated by a specified
interval.
[00100] In some embodiments, multiple components associated with the
distillation
system 1100 can be modified in a coordinated fashion (e.g., simultaneously,
serially) to
achieve a desired result. For example, if the boiling rate above the heat-
transfer element
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1120 is below a specified (e.g., desirable) level, the flow of fluid boiled
from fluid 1114 can
be increased by modifying the angle 1112 of the heat-transfer element 1120 to
increase the
flow-rate of fluid 1114 and by increasing the speed of a motor of the
compression component
1130. In some embodiments, the control unit 1110 can be configured to control
one or more
portions of multiple distillation systems (not shown) through a wired network
and/or wireless
network.
[00101] In some embodiments, the distillation system 1100 can have a user-
interface (not
shown) that can be used by a user to manually change an aspect of the
distillation system
1100. For example, a user can change a flow-rate of a fluid associated with
the distillation
system 1100 or a heat-transfer rate of the heat-transfer element 1120 via the
user-interface.
In some embodiments, a user can change an operating point of one or more
portions of the
distillation system 1100 via a user-interface. The control unit 1110 can be
configured to
modify, for example, a flow-rate and/or an angle of the heat-transfer element
1120 to
implement the operating point change.
[00102] In some embodiments, for example, a heating component (not shown),
such as an
electric heater, can be temporarily used during a transition to a particular
operating point of at
least a portion of the distillation system 1100. For example, if the operating
temperature of
the boiler portion 1140 were increased, a heating component can be used to
temporarily heat
an incoming salt-water stream (not shown) until a steady-state condition is
attained. In some
embodiments, a heating component can be permanently used to maintain a steady-
state
condition of a portion of the distillation system 1100.
[00103] FIG. 12 is a flowchart that illustrates a method for modifying an
angle of a heat-
transfer element of a distillation system, according to an embodiment of the
invention. The
flow chart shows that a fluid with an impurity concentration is received at a
housing of a
distillation system at 1210. A signal from a sensor associated with the
distillation system
received at 1220. In some embodiments, the sensor can be a temperature sensor
or a pressure
sensor.
[00104] An angle of a heat-transfer element coupled to the housing is modified
based on
the signal at 1230. For example, when a threshold condition is satisfied based
on the signal,
a control unit can trigger an actuator to change the angle of the heat-
transfer element. In
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some embodiments, a flow-rate of at least a portion of a fluid can also be
modified in
addition to, or in place of, the angle of the heat-transfer element being
modified.
[00105] FIG. 13 is a flowchart that illustrates a method for initiating a
distillation system,
according to an embodiment of the invention. The flowchart illustrates that at
least a portion
of a housing of a distillation system is evacuated using a vacuum pump at
1300. The housing
of the distillation system, in some embodiments, must be evacuated if one or
more portions
of the distillation system are configured to operate at a low pressure. In
some embodiments,
the vacuum pump is not necessary because the distillation system is configured
to operate at,
for example, atmospheric pressure. In some embodiments, a blower is needed to
increase a
pressure of the distillation system to a high pressure operating point.
[00106] A compression component coupled to the housing is initiated at 1310. A
fluid
flowing to the housing of the distillation system is heated using a heating
component at 1320.
The fluid can be a mixture of two or more substances. In some embodiments, the
fluid can
be heated to an operating temperature of a boiler portion of the distillation
system. In some
embodiments, the heating component can be, for example, an electric heating
component
only used during start-up. In some embodiments, a cooling component is needed
to decrease
a temperature of an incoming and/or outgoing stream of the distillation system
to a low
temperature operating point.
[00107] The operation of the vacuum pump and the heating component are
terminated
when the distillation system attains steady-state at 1330. In some
embodiments, the
distillation system operates at steady state when a boiler portion of the
distillation system and
a condenser portion of the distillation system reach their respective
operating points. At the
steady-state operating point, a heat-transfer rate of a heat-transfer element
disposed within
the housing of the distillation system is substantially constant.
[00108] Some embodiments relate to a computer storage product with a computer-
readable medium (also can be referred to as a processor-readable medium)
having
instructions or computer code thereon for performing various computer-
implemented
operations. The media and computer code (also can be referred to as code) may
be those
specially designed and constructed for the specific purpose or purposes.
Examples of
computer-readable media include, but are not limited to: magnetic storage
media such as
hard disks, floppy disks, and magnetic tape; optical storage media such as
Compact
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Disc/Digital Video Discs (CD/DVDs), Compact Disc-Read Only Memories (CD-ROMs),
and holographic devices; magneto-optical storage media such as floptical
disks; carrier wave
signals; and hardware devices that are specially configured to store and
execute program
code, such as application specific integrated circuits (ASICs), Programmable
Logic Devices
(PLDs), and ROM and random-access memory (RAM) devices. Examples of computer
code
include, but are not limited to, micro-code or micro-instructions, machine
instructions, such
as produced by a compiler, and files containing higher-level instructions that
are executed by
a computer using an interpreter. For example, an embodiment of the invention
may be
implemented using Java, C++, or other object-oriented programming language and
development tools. Additional examples of computer code include, but are not
limited to,
control signals, encrypted code, and compressed code.
[00109] In conclusion, among other things, methods and apparatus for
distillation over a
wide range of temperatures and pressures are described. While various
embodiments have
been described above, it should be understood that they have been presented by
way of
example only, and various changes in form and details may be made. For
example, any
combination of the components in the distillation systems shown in the figures
can be used to
create a different and/or separate distillation system. In some embodiments,
for example,
some of the components of the distillation system shown in FIG. 2 can be
combined with the
distillation systems shown in FIGS. l0A and 11.
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