U.S. patent application number 11/917878 was filed with the patent office on 2010-10-21 for method and apparatus for liquid disinfection using light transparent conduit.
Invention is credited to Uri Levy, Ytzhak Rozenberg, Zohar Vardiel.
Application Number | 20100264329 11/917878 |
Document ID | / |
Family ID | 39048009 |
Filed Date | 2010-10-21 |
United States Patent
Application |
20100264329 |
Kind Code |
A1 |
Vardiel; Zohar ; et
al. |
October 21, 2010 |
METHOD AND APPARATUS FOR LIQUID DISINFECTION USING LIGHT
TRANSPARENT CONDUIT
Abstract
Some demonstrative embodiments of the invention include an
illumination-based liquid disinfection device. The disinfection
device may include, for example, a light transparent conduit to
carry a flowing liquid to be disinfected, the conduit having an
inlet to receive the liquid and an outlet to discharge the liquid,
a substantially light transparent sleeve having external dimensions
smaller than the internal dimensions of the conduit, the sleeve
positioned within the conduit substantially perpendicular to the
axis of symmetry of the conduit and a light source positioned
within the sleeve.
Inventors: |
Vardiel; Zohar; (Or Yehuda,
IL) ; Levy; Uri; (Rehovot, IL) ; Rozenberg;
Ytzhak; (Ramat Gan, IL) |
Correspondence
Address: |
Pearl Cohen Zedek Latzer, LLP
1500 Broadway, 12th Floor
New York
NY
10036
US
|
Family ID: |
39048009 |
Appl. No.: |
11/917878 |
Filed: |
November 14, 2007 |
PCT Filed: |
November 14, 2007 |
PCT NO: |
PCT/IL07/01409 |
371 Date: |
June 8, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60858727 |
Nov 14, 2006 |
|
|
|
Current U.S.
Class: |
250/436 |
Current CPC
Class: |
C02F 2201/3225 20130101;
C02F 2201/3227 20130101; C02F 2201/3228 20130101; C02F 1/325
20130101; A61L 2/10 20130101; C02F 2201/007 20130101 |
Class at
Publication: |
250/436 |
International
Class: |
A61L 2/10 20060101
A61L002/10 |
Claims
1. An apparatus for liquid disinfection by light, the apparatus
comprising: a substantially light transparent conduit to carry
flowing liquid to be disinfected; a substantially light transparent
sleeve having external dimensions smaller than the internal
dimensions of the conduit, the sleeve positioned within the conduit
substantially perpendicular to the axis of symmetry of the conduit;
and a light source positioned within the sleeve.
2. The apparatus of claim 1, wherein the transparent sleeve
comprises quartz.
3. The apparatus of claim 1, wherein the conduit comprises
quartz.
4. The apparatus of claim 1, wherein the transparent sleeve is
being fused to said conduit.
5. The apparatus of claim 1 comprising additional sleeves
positioned within the conduit substantially perpendicular to the
axis of symmetry of the conduit.
6. The apparatus of claim 1, wherein the transparent sleeve has a
hydro-dynamic shape.
7. The apparatus of claim 1, wherein the transparent sleeve has a
patterned surface directed to affect light distribution inside the
conduit.
8. The apparatus of claim 1, wherein one or more objects are
positioned within the conduit to affect the water flow pattern.
9. The apparatus of claim 1, wherein one or more objects are
positioned within the conduit to affect the light distribution
within the conduit.
10. The apparatus of claim 1, wherein the conduit has a
substantially cylindrical shape with varying diameter size at least
at one portion of the conduit.
11. The apparatus of claim 1, wherein a portion of an external
surface of the conduit is coated with a UV reflective coating.
12. The apparatus of claim 1, wherein the conduit comprises an
inlet to receive the liquid, one or more branches to carry the
liquid and an outlet to discharge the liquid.
13. The apparatus of claim 1, wherein the conduit is positioned
within a metal container having a see-through window.
14. The apparatus of claim 1, wherein the light source is an
ultraviolet light source.
15. The apparatus of claim 1, wherein the light source has a
non-cylindrical elongated shape.
16. The apparatus of claim 1, wherein the conduit comprises two
light transparent sections separated by a metal housing containing
the sleeve.
17. The apparatus of claim 16, wherein the internal surface of the
metal housing is coated by an ultraviolet reflecting coating.
18. The apparatus of claim 17, wherein the ultraviolet reflecting
coating is coated with a UV transparent, UV resistant coating.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This Application is a National Phase of PCT Application No.
PCT/IL2007/001409, International filing date Nov. 14, 2007,
claiming priority of U.S. patent application Ser. No. 60/858,727,
filed on Nov. 14, 2006.
BACKGROUND OF THE INVENTION
[0002] Ultraviolet liquid disinfection systems using UV light
source located within a metallic chamber through which the liquid
flow have been long known. The walls of such a metallic chamber
absorb most of the incident UV light and light rays emitted from
the UV light source traverse through the water once and are
essentially absorbed by the metal. Accordingly, such systems do not
utilize the light source in an efficient manner. There is a need
for a UV disinfection system that would be more efficient than
existing systems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0003] The subject matter regarded as the invention is particularly
pointed out and distinctly claimed in the concluding portion of the
specification. The invention, however, both as to organization and
method of operation, together with objects, features and advantages
thereof, may best be understood by reference to the following
detailed description when read with the accompanied drawings in
which:
[0004] FIGS. 1A and 1B are conceptual illustrations of a
disinfection system according to some demonstrative embodiments of
the invention;
[0005] FIG. 2A is an illustration of an exemplary disinfection
system according to some demonstrative embodiments of the
invention;
[0006] FIG. 2B is a cross sectional view of the exemplary
disinfection system of FIG. 2A;
[0007] FIG. 3 depicts an exemplary illustration of a UV-transparent
conduit according to some demonstrative embodiments of the
invention;
[0008] FIG. 4 is a side view of a conceptual illustration of an
exemplary UV-transparent conduit having a reflective coating on
portions of its surface according to some demonstrative embodiments
of the invention;
[0009] FIGS. 5A-5C are schematic illustrations of conduits
according to some demonstrative embodiments of the invention;
[0010] FIGS. 6A and 6B are illustrations of disinfectors having
flow-forming objects according to some demonstrative embodiments of
the invention;
[0011] FIG. 7 is a cross section schematic illustration of a
non-cylindrical sleeve according to some demonstrative embodiments
of the invention;
[0012] FIG. 8 is a conceptual illustration of an exemplary
disinfection system having a patterned sleeve according to some
demonstrative embodiments of the invention;
[0013] FIG. 9 is a conceptual illustration of an exemplary
disinfection system having a non-cylindrical light source according
to some demonstrative embodiments of the invention;
[0014] FIG. 10 is a schematic illustration of a 2-pipe disinfection
system according to some demonstrative embodiments of the
invention.
[0015] FIGS. 11A-11C are exemplary illustrations demonstrating the
modular nature of a disinfection system according to embodiments of
the invention;
[0016] FIGS. 12A-12C are schematic illustrations of light flux
distribution within an exemplary conduit based on computer
simulations according to embodiments of the invention;
[0017] FIG. 12D is a dose distribution histogram associated with
the simulation of FIGS. 12A-12C;
[0018] FIGS. 13A-13B are schematic illustrations of light flux
distribution within a stainless steel conduit based on computer
simulations according to embodiments of the invention; and
[0019] FIG. 13C is a dose distribution histogram associated with
the simulation of FIGS. 13A-13B.
[0020] It will be appreciated that for simplicity and clarity of
illustration, elements shown in the drawings have not necessarily
been drawn accurately or to scale. For example, the dimensions of
some of the elements may be exaggerated relative to other elements
for clarity or several physical components included in one
functional block or element. Further, where considered appropriate,
reference numerals may be repeated among the drawings to indicate
corresponding or analogous elements. Moreover, some of the blocks
depicted in the drawings may be combined into a single
function.
DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION
[0021] In the following detailed description, numerous specific
details are set forth in order to provide a thorough understanding
of the invention. However, it will be understood by those of
ordinary skill in the art that the present invention may be
practiced without these specific details. In other instances,
well-known methods, procedures, components and circuits may not
have been described in detail so as not to obscure the present
invention.
[0022] Some demonstrative embodiments of the invention include an
ultraviolet (UV) disinfection system having a conduit to carry
liquid to be disinfected and an illumination source located inside
a transparent sleeve positioned substantially perpendicular to the
longitudinal axis of symmetry of the conduit and the direction of
flow of the liquid.
[0023] It will be appreciated that the liquid disinfection process
may include inactivation or removal of any organism, bacteria,
microorganism, being, creature, microbe, germ, virus, organic
contaminator, non-organic contaminator, oxidizeable toxic or
contaminator; any cumulative noxious species of biological or
chemical origin; any oxidizing particle, fragment or element, e.g.,
Hydrogen peroxide or Titanium dioxide, intended to oxidize a
contaminator and/or the like. Some demonstrative embodiments of the
invention may refer to using ultraviolet (UV) light to disinfect
the liquid and/or to oxidize particles within the liquid. However,
it will be appreciated by those skilled in the art, that in other
embodiments of the invention, light of any other suitable spectrum
may be used.
[0024] Reference is now made to FIGS. 1A and 1B, which conceptually
illustrate a disinfection system according to some demonstrative
embodiments of the invention. A disinfection system 100 may include
a tube or conduit 101 to carry liquid to be disinfected, one or
more substantially light-transparent sleeves 102 positioned within
conduit 101 substantially perpendicular to its longitudinal axis of
symmetry 109 and one or more light sources 104, each positioned
within a respective sleeve 102. According to embodiments of the
invention light sources 104 may be UV light sources capable of
emitting light at 254 nm. Conduit 101 may have an inlet 106 to
receive from an external liquid pipe the liquid to be disinfected
and an outlet 108 to discharge the liquid via an external discharge
pipe. System 100 may further include adaptors 110 to connect
conduit 101 to the external liquid pipes. The adaptors may comprise
O-rings to ensure water-tight connections between the external
pipes and the conduit.
[0025] Conduit 101 may be substantially made of UV-transparent
glass, such as quartz. UV-transparent sleeves 102 may be for
example quartz or Teflon.RTM. sleeves. Each Sleeve 102 may have
external dimensions smaller than the internal dimensions of conduit
101 such that liquid may flow within conduit 101 around sleeves
102. Both ends of sleeve 102 may extend from the walls of conduit
101 to enable replacement of light source 104 within sleeve 102.
Light sources 104 may illuminate the liquid to be disinfected when
flowing in the conduit. In this configuration, the liquid within
conduit 101 may act as a waveguide and at least part of the light,
for example, at least half of the emitted UV intensity, may be
totally-internally reflected at the interface of the UV-transparent
conduit 101 and the air surrounding it. Conduit 101 may be located
inside a protective metal sleeve with an air gap between the
conduit and the sleeve, as shown for example, in FIG. 2B. The total
internal reflection (TIR) effect is demonstrated in FIG. 1B.
[0026] Although the invention is not limited in this respect, light
source 104 may generate UV light of a suitable UV-germicidal
spectrum. For example, light source 104 may include one or more UV
lamps, e.g., a low-pressure UV lamp, a low-pressure high output UV
lamp, a medium-pressure UV lamp, a high-pressure UV lamp, and/or a
microwave-excited UV lamp, as are all known in the art.
[0027] According to embodiments of the invention, the liquid may
act as a waveguide and at least part of the light, for example, at
least half of the emitted UV intensity, may be totally-internally
reflected at the interface of the glass conduit and air surrounding
it. According to other embodiments of the invention, at least 70%
of the emitted UV intensity may be totally-internally reflected at
the interface of the glass conduit and air surrounding it. As
shown, in FIG. 1B, the liquid to be disinfected may flow around
each of light sources 104. In such a configuration, the system may
include an additional light source to enable disinfection of the
liquid to the required level even when one of the light sources 104
is fully or partially dysfunctional. For example, the disinfection
process may continue while a non-functional light source is being
replaced or fixed.
[0028] It should be noted that embodiments of the present
invention, in which light sources 104 are located substantially
perpendicular to the direction of flow of the liquid within conduit
101 may ensure that each light source is capable of illuminating
substantially the entire flow of liquid when the flow traverses
that particular light source.
[0029] Reference is now made to FIG. 2A, which shows an exemplary
disinfection system and to FIG. 2B, which is a cross sectional view
of the exemplary disinfection system according to some embodiments
of the invention. An exemplary disinfection system 200 may include
a substantially UV-transparent conduit 201 to carry liquid to be
disinfected, substantially UV-transparent sleeves 202A and 202B
positioned within conduit 201 substantially perpendicular to its
axis of symmetry 209 and one or more UV-light sources 204, each
positioned within a respective sleeve 202. In this exemplary
configuration, sleeves 202A and 202B are orthogonal to each
other.
[0030] It should, however, be understood to a person skilled in the
art, that according to embodiments of the present invention,
UV-transparent sleeves 202 may be positioned with respect to each
other, at any rotational angle around the longitudinal axis of
symmetry 209 of conduit 201. According to other embodiments of the
present invention, UV-transparent sleeves 202 may be positioned at
any rotational angle around other axis of symmetry of conduit 201.
Although a symmetrical cylinder-shaped conduit is shown, it should
be understood to a man skilled in the art that the conduit may have
other shapes, not necessarily symmetrical, as described in detail
with respect to FIG. 5A-5C.
[0031] Conduit 201 may be located inside a protective metal tube
203 forming an air gap 208 between conduit 201 and metal tube 203.
Although the scope of the present invention is not limited in this
respect, external tube 103 may include a see-through window 210
made of transparent material such as glass, plastic or any other
suitable material to enable an operator to view conduit 201 and a
cover 212 to cover window 210 when desired. Although in the
exemplary illustration of FIG. 2A, a single see-through window is
shown, it should be understood to a person skilled in the art that
the invention is not limited in this respect and according to
embodiments of the present invention tube 203 may include more than
one see-through window at any size and/or shape.
[0032] Reference is now made to FIG. 3, which depicts an exemplary
illustration of a conduit having four sleeves according to some
demonstrative embodiments of the invention. The exemplary conduit
301 of FIG. 3 includes four UV-transparent sleeves 302A-302D
positioned within conduit 301 substantially perpendicular to its
longitudinal axis of symmetry 309. In this exemplary configuration,
pairs of adjacent sleeves are orthogonal to each other.
Accordingly, sleeves 302A and 302B are orthogonal to each other;
sleeves 302B and 302C are orthogonal to each other; and sleeves
302C and 302D. Further, pairs of alternating sleeves are parallel
to each other. Accordingly, sleeves 302A and 302C are parallel to
each other; and likewise sleeves 302B and 302D are parallel to each
other. It should, however, be understood to a person skilled in the
art, that according to embodiments of the present invention,
UV-transparent sleeves 302 may be positioned with respect to each
other, at any rotational angle around the axis of symmetry 309 of
conduit 301. Sleeves may be fused to conduit 301 to form a single
glass structure.
[0033] According to other embodiments of the present invention,
sleeve 202 may be attached to conduit 301 using housing, adaptors,
connectors or any suitable means known in the art. For example,
each of areas 316A-316D may be a metal housing for one of sleeves
302A-302D. The metal housing may be coated on its interior surface
with a reflective coating to increase the efficiency of the
disinfection process. According to embodiments of the invention,
the reflective coating may be coated with a UV-transparent, UV
resistive and bio-compatible coating, for example a Teflon.RTM.
coating.
[0034] Although, the sleeves are illustrated as being cylindrical,
it should, be understood to a person skilled in the art that
embodiments of the invention are not limited in this respect and
the sleeve may have other suitable shapes, such as hydrodynamic
shapes, as detailed below with respect to FIG. 7.
[0035] Reference is now made to FIG. 4, which conceptually
illustrates a side view of an exemplary conduit having a reflective
coating on portions of its surface according to some embodiments of
the invention. A sleeve 402 may be positioned within conduit 401
such that sleeve 402 is substantially perpendicular to the
longitudinal axis of symmetry 409 of conduit 401. UV-light source
404 may be positioned within sleeve 402. As both sleeve 402 and
conduit 401 are substantially transparent to UV light, the liquid
may act as a waveguide and at least part of the light, for example,
rays 410 and 411 may be totally-internally reflected at the
interface of conduit 401 and the air surrounding it 408.
[0036] Still, rays such as ray 413 having an angle with the surface
of the conduit above a critical angle cannot undergo total internal
reflection (TIR). Such a ray is transmitted outside the liquid
after traversing the liquid only once. Conduit 401 may include one
or more minors or UV reflective coating areas 407 to reflect
non-guided rays, for example, ray 412 back into the liquid.
[0037] According to some embodiments of the present invention, at
least portions of the exterior surface of conduit 401 may be coated
with UV reflective coating 407 to produce rear surface mirror
effect, e.g., to allow a larger portion of the light from light
source 404 to illuminate the liquid flowing in conduit 401. Coating
407 may reflect back into the liquid additional light rays reaching
the surface in relative proximity to sleeve 402. Reflective coating
407 may comprise aluminum deposition, gold deposition or
multi-layer dielectric material. Any other suitable reflective
coating may be used. According to other embodiments of the
invention, the entire surface of the conduit may be coated with
reflective coating to enhance the back-mirror effect.
[0038] Although the scope of the present invention is not limited
in this respect, at least a portion of conduit 401, e.g., area 414
surrounding light source 404 may be from a material having
UV-reflection properties, for example, aluminum or any other metal.
Reflecting area 414 may reflect back into the liquid non-guided
light rays that cannot undergo TIR, such as ray 413. Reflecting
area 414 may include a UV-reflecting coating on its inner surface
or may be covered by a thin sheet made of material having
UV-reflecting properties. The UV-reflecting coating or sheet may be
protected against water damage by coating it with a UV-resistive,
UV-transparent coating such as Teflon.RTM..
[0039] Reference is now made to FIGS. 5A, 5B and 5C, which depict
schematic illustrations of conduits having varying diameters along
their lengths according to some demonstrative embodiments of the
invention. The shape of the conduit may be pre-determined to
increase the efficiency of the disinfection process. According to
embodiments of the present invention, the internal diameter of
conduit 501 may vary along its length, as depicted in the
demonstrative illustration of FIGS. 5A, 5B and 5C. The specific
shape of the conduit may affect the liquid flow pattern and the
shape may be pre-determined in order to increase the overall
efficiency of the disinfection system. It should be understood that
conduit 501 may have any other symmetrical or non-symmetrical
shape.
[0040] Reference is now made to FIGS. 6A and 6B, which depict
schematic illustrations of a portion of disinfection systems having
flow-forming objects according to some embodiments of the present
invention. Each of disinfection systems 600A and 600B may include a
conduit 601 to carry liquid to be disinfected, a substantially
UV-transparent sleeves 602 positioned within conduit 601
substantially perpendicular to its longitudinal axis of symmetry
and a UV-light sources 604 positioned within sleeve 602. Conduit
601 may include one or more objects 614 affixed to the conduit. As
illustrated in FIG. 6A, objects 614 may be attached to a protrusion
to be located in relative distance from the surface of the conduit.
As illustrated in FIG. 6B, objects 614 may be attached to the
surface of the conduit or located in relative proximity to the
surface. Objects 614 may be pre-designed and may be located in
specific positions in conduit 601 to affect the liquid flow
pattern. Additionally or alternatively, UV-transparent objects
and/or UV-scattering objects and/or UV-reflective objects may be
affixed, attached or added to conduit 601. The flow-forming objects
may affect the liquid flux and the distribution of liquid tracks
and the objects shape and location may be pre-determined in order
to increase the overall efficiency of the disinfection process. The
light scattering objects and/or light reflective objects may
influence the spatial distribution of UV light intensity and the
objects shape and location may be pre-determined in order to
increase the overall efficiency of the disinfection process.
[0041] Reference is now made to FIG. 7, which depict schematic
cross section illustration of non-cylindrical sleeve according to
some demonstrative embodiments of the invention. According to
embodiments of the present invention, sleeve 702 may have a
hydrodynamic shape to prevent the formation of liquid stagnation
zone where liquid may flow at a low velocity in proximity to sleeve
702 at the area facing the outlet of the conduit. The specific
shape of sleeve 702 may be designed to improve light distribution
and liquid flow pattern in order to increase the overall efficiency
of the disinfection system. It should be understood to a person
skilled in the art that sleeve 702 having a non-cylindrical shape
may be positioned within a substantially UV-transparent conduit
substantially perpendicular to the direction of liquid flow.
Alternatively, the non-cylindrical sleeve may be positioned within
non-transparent containers such as stainless steel conduits or
reactors.
[0042] Reference is now made to FIG. 8, which is a conceptual
illustration of an exemplary disinfection system having a patterned
sleeve according to some demonstrative embodiments of the
invention. A sleeve 802 may be positioned within conduit 801 such
that sleeve 802 is substantially perpendicular to the longitudinal
axis of symmetry of conduit 801. UV-light source 804 may be
positioned within sleeve 802. As both sleeve 802 and conduit 801
are substantially transparent to UV light, the liquid may act as a
waveguide and at least part of the light may be totally-internally
reflected at the interface of conduit 801 and its surroundings. For
another portion of the light that cannot undergo TIR, conduit 801
may include one or more mirrors or UV reflective coating areas 807
to reflect rays back into the liquid. Still, certain rays may evade
both TIR and the UV reflective areas.
[0043] According to embodiments of the invention, sleeve 802 may
include one or more objects 805 located in specific positions and
shaped in order to influence the light distribution inside conduit
801. Object 805 may be UV-scattering or UV-reflecting objects made
of any suitable material. For example, ray 820 is directed toward
area 821, which is not coated with reflective coating. Accordingly,
in a non-patterned sleeve such a ray would traverse the liquid for
a short distance before exiting the conduit via area 821. Instead
by using sleeve 802, ray 820 may hit object 805, change its
direction (arrow 822) and reach reflective area 807 to be reflected
back into the liquid.
[0044] Although, the patterned sleeve is described as being
positioned within a substantially UV-transparent conduit
substantially perpendicular to the direction of liquid flow, it
should, be understood to a person skilled in the art that
embodiments of the invention are not limited in this respect and
embodiments of the invention are likewise applicable to using such
a patterned sleeve at any position relative to the liquid flow
within any container or conduit including non-transparent
containers such as stainless steel conduits or reactors.
[0045] Reference is now made to FIG. 9, which is a conceptual
illustration of an exemplary disinfection system having a
non-cylindrical light source according to some demonstrative
embodiments of the invention. A sleeve 902 may be positioned within
conduit 901 such that sleeve 902 is substantially perpendicular to
the longitudinal axis of symmetry of conduit 901. UV-light source
904 may be positioned within sleeve 902. As both sleeve 902 and
conduit 901 are substantially transparent to UV light, the liquid
may act as a waveguide and at least part of the light may be
totally-internally reflected at the interface of conduit 901 and
its surroundings. For another portion of the light that cannot
undergo TIR, conduit 901 may include one or more mirrors or UV
reflective coating areas 907 to reflect rays back into the liquid.
Light source 904 may have a non-cylindrical geometry; for example,
its cross section may be an ellipse or any other desired shape to
generated controlled light distribution. For example, the shape of
the lamp may be directed to generate a non-circular light
distribution such that more light rays would be directed to the
direction of the liquid flow than to the surface of conduit 901.
The specific shape of light source 904 may be designed according to
the specific characteristics of the system's geometry and the
disinfection process in order to increase the overall efficiency of
the disinfection system.
[0046] Although, the non-cylindrical light source is described as
being positioned within a substantially UV-transparent conduit
substantially perpendicular to the direction of liquid flow, it
should, be understood to a person skilled in the art that
embodiments of the invention are not limited in this respect and
embodiments of the invention are likewise applicable to using such
a light source at any position relative to the liquid flow within
any container or conduit including non-transparent containers such
as stainless steel conduits or reactors.
[0047] Reference is now made to FIG. 10, which depicts an exemplary
illustration of a 2-pipe disinfection system according to
embodiments of the invention. A disinfection system 140 may include
a conduit 141 to carry liquid to be disinfected. Conduit 141 may
include more than one branch, for example two branches, 143A and
143B to increase the liquid flow. Having more than one branch may
enable better control of the internal pressure in conduit 141.
Conduit 141 may have an inlet 146 to receive from an external
liquid pipe the liquid to be disinfected and an outlet 148 to
discharge the liquid via an external discharge pipe.
[0048] System 140 may include one or more substantially
UV-transparent sleeves 142A positioned within branch 143A
substantially perpendicular to its longitudinal axis of symmetry
149A and one or more UV-light sources 144A, each positioned within
a respective sleeve 142A. System 140 may further include one or
more substantially UV-transparent sleeves 142B positioned within
branch 143B substantially perpendicular to its longitudinal axis of
symmetry 149B and one or more UV-light sources 144B, each
positioned within a respective sleeve 142B.
[0049] It should be understood to a person skilled in the art that
although a 2-branch conduit is described, embodiments of the
invention are not limited in this respect and a disinfection system
according to other embodiments of the present invention may include
more than 2 branches for liquid flow.
[0050] FIGS. 11A-11C demonstrate the modular nature of an exemplary
disinfection system according to embodiments of the invention.
According to some embodiments of the present invention, the liquid
flow section of the disinfection system may be constructed from two
types of modular building blocks, conduit elements 151 and sleeve
elements 152. Sleeve elements 152 may include a ring 153 having a
UV-transparent sleeve 154 positioned within. The internal diameter
or ring 153 is larger than the external diameter of sleeve 154.
Element 152 may further include a UV-light source positioned within
sleeve 154. Both ends of element 152 may include adaptors,
connectors or a screw mechanism to be connected to one or more of
conduits 151. Conduit elements 151 may be substantially made of
UV-transparent material, such as quartz as described in detail
above. The external diameter of conduit 151 may be substantially
similar to the external diameter of ring 153. Both ends of conduits
151 may include adaptors, connectors or a screw mechanism to be
connected to one or more of elements 152. The connections between
conduits 151 and sleeve parameters 152 may be water-tight
connections.
[0051] Although the scope of the present invention is not limited
in this respect, at least one sleeve element 152 and two conduit
elements 151 may create a conduit set to carry liquid to be
disinfected as described above. A conduit set may comprise a number
of n sleeve elements 152 and a number of n+1 conduit elements 151.
For example, as shown in FIG. 11B conduit 150 may comprise one
sleeve element 152 and two conduit elements 151. Another example,
shown in FIG. 11C, conduit 160 may comprise two sleeve elements 152
and three conduit elements 151.
[0052] Although in the exemplary illustration of FIGS. 11A-11C,
conduits 150 and 160 are shown, it should be understood to a person
skilled in the art that the invention is not limited in this
respect and according to embodiments of the present invention any
combination of n+1 conduit elements 151 and n sleeve elements 152
may be connected to create a conduit set.
[0053] Although, embodiments of the present invention are not
limited in this respect, it is understood and simulated that a
pre-designed structure according to embodiments of the present
invention improves the efficiency of UV disinfection and increase
kill probability, namely the probability to inactivate the entities
being in the liquid flowing in conduit 101.
[0054] Computer Simulations
[0055] Following, are examples relating to illumination flux
distributions in accordance with some demonstrative embodiments of
the invention. It should be noted that the illumination-flux
distributions used in these examples are not intended to limit the
scope of the invention to any particular configuration and/or
illumination flux distribution.
[0056] FIGS. 12A-12C illustrate computer simulations of light flux
distribution within an exemplary conduit during a liquid
disinfection process. The simulated system is an exemplary system
according to embodiments of the invention. The system includes one
UV light source within a quartz sleeve positioned in the center of
a quartz conduit such that the sleeve is perpendicular to the
longitudinal axis of symmetry of the conduit defining the Z
direction. The longitudinal axis of the sleeve defined the X
direction. The calculations were performed for a flow of liquid of
50 m.sup.3/h. The length of the conduit was taken to be 800 mm, the
internal diameter of the conduit as 75 mm, the external diameter of
the sleeve protecting the UV light source as 44 mm and the pressure
drop as .DELTA.P(at 50 m.sup.3/h)=0.27 [bar]. The liquid used for
the computer simulations was clear water with UVT (ultraviolet
transmission) of 98%.
[0057] FIG. 12A is a cross section in the Y-Z plane of a portion of
the conduit illustrating the light flux distribution between the
light source and the outlet end of the conduit. FIG. 12B is a cross
section in the X-Z plane of the same portion of the conduit
illustrating the light flux distribution between the light source
and the outlet end of the conduit. FIG. 12C is a cross section in
the Y-Z plane of the entire conduit illustrating the light flux
distribution between the inlet end and the outlet end of the
conduit. As can be seen, the light reaches trough the entire length
of the tube at a substantial intensity. FIG. 12D shows a graph
illustrating the calculated normalized UV dose distribution within
the quartz conduit. The normalized dose distribution function is
closed to being a Gaussian function.
[0058] As comparative data, FIGS. 13A and 13B illustrate computer
simulations of light flux distribution within a conventional
stainless steel container having 20% reflection during a liquid
disinfection process. All the other parameters used in the
comparative simulation were similar to the simulations of FIGS.
12A-12C. As can be seen, the intensity of light is practically zero
after 50 mm is the Z direction. FIG. 13C shows a graph illustrating
the UV dose distribution within the conventional stainless steel
conduit. As expected, the average dose within the stainless steel
conduit having a value of {48 [mJ/cm.sup.2]} is much smaller than
the average dose of the quartz conduit with a value of {228
[mJ/cm.sup.2]}. The dose distribution of the conventional stainless
steel conduit is wider than dose distribution of the quartz
conduit.
[0059] While certain features of the invention have been
illustrated and described herein, many modifications,
substitutions, changes, and equivalents may occur to those of
ordinary skill in the art. It is, therefore, to be understood that
the appended claims are intended to cover all such modifications
and changes as fall within the true spirit of the invention.
* * * * *