Title: Method and apparatus for water purification
Abstract: An apparatus for disinfecting a fluid includes a tube connected with a source of the fluid. The tube allows the fluid to be transported from the source to a discharge. An ultraviolet lamp is positioned adjacent the tube, and is adapted to transmit light waves through the fluid. The tube can be a coiled tube having one or more coils thereby forming a helical tube. Each coil of the helical tube has an inner diameter and an outer diameter. The inner diameters of the coils define a space or opening. The ultraviolet lamp is positioned within the opening. A fluid passing through the coils of the tube are exposed to the ultraviolet light. The method of the invention includes moving water from a source to a discharge, through the tube while the lamp is activated. Water will become disinfected as it is exposed to the ultraviolet light of the lamp.
Patent Number: 6,946,651 Issued on 09/20/2005 to Bohne
| Inventors:
|
Bohne; Mark F. (311 E. Mason Rd., Milan, OH 44846)
|
| Assignee:
|
Milan (OH)
|
| Appl. No.:
|
412142 |
| Filed:
|
April 11, 2003 |
| Current U.S. Class: |
250/236; 250/235; 250/238 |
| Intern'l Class: |
C02F 001/32 |
| Field of Search: |
250/435,436,432.R
|
References Cited [Referenced By]
U.S. Patent Documents
| 4956754 | Sep., 1990 | Chen.
| |
| 5474748 | Dec., 1995 | Szabo.
| |
| 5597487 | Jan., 1997 | Vogel et al.
| |
| 5675153 | Oct., 1997 | Snowball.
| |
| 5874741 | Feb., 1999 | Matschke.
| |
| 5994146 | Nov., 1999 | Wright et al.
| |
| 6120691 | Sep., 2000 | Mancil.
| |
| 6332981 | Dec., 2001 | Loyd.
| |
| 6610258 | Aug., 2003 | Strobbel et al.
| |
| 2002/0162968 | Nov., 2002 | Snowball.
| |
Primary Examiner: Wells; Nikita
Assistant Examiner: Smith, II; Johnnie L
Attorney, Agent or Firm: MacMillan, Sobanski & Todd, LLC
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/372,955
filed Apr. 16, 2002, the disclosure of which is incorporated herein by reference.
Claims
1. An apparatus for disinfecting a fluid delivered from a source comprising:
a tube connected with the source for transporting the fluid from the source to
a discharge, said tube having a plurality of adjacent coils forming a helix; and
an ultraviolet lamp positioned adjacent the tube, wherein the lamp is adapted
to transmit light waves directly at the fluid within the tube such that the light
is dispersed outwardly from the apparatus such that the light is not reflected
back towards the apparatus except by the tube itself;
wherein the space between adjacent coils of the helix is less than the diameter
of the helical tube, such that the helix substantially surrounds the ultraviolet
lamp, thereby not requiring the apparatus to be disposed within a reflective chamber.
2. The apparatus defined in claim 1 wherein an inner surface of each coil defines
an inner diameter, said inner diameters defining openings; and
the ultraviolet lamp is positioned within the openings.
3. The apparatus defined in claim 2 wherein the opening of the helical tube has
a first diameter;
the ultraviolet lamp has a second diameter; and
the first diameter is larger than the second diameter.
4. The apparatus defined in claim 1 wherein each of the coils have an inner diameter
defining an opening; and
the ultraviolet lamp is positioned within the openings.
5. The apparatus defined in claim 4 wherein the ultraviolet lamp is centrally
positioned within the opening.
6. The apparatus defined in claim 4 wherein a plurality of ultraviolet lamps
are positioned within the opening.
7. The apparatus defined in claim 6 wherein the plurality of ultraviolet lamps
are equally spaced about the opening.
8. The apparatus defined in claim 1 wherein the ultraviolet lamp is a germicidal lamp.
9. The apparatus defined in claim 1 wherein the lamp is linearly shaped.
10. The apparatus defined in claim 1 wherein the helical tube is a quartz tube.
11. The apparatus defined in claim 1 wherein the helical tube is a germicidal
glass tube.
12. A method of disinfecting water comprising:
providing a source of water,
providing a tube connected to the source of water, said tube being transparent
to ultraviolet light and having a plurality of adjacent coils, said coils forming
the tube;
providing an ultraviolet light source;
positioning the light source adjacent the tube;
activating the light source to generate high-intensity ultraviolet light waves
that are directed at the tube such that the light is dispersed outwardly from the
apparatus such that the light is not reflected back towards the apparatus;
supplying the fluid into the tube from the source of water; and
collecting the disinfected water in a receptacle;
wherein the spacing between adjacent coils is less than the diameter of the tube
such that the coils substantially surround the ultraviolet lamp thereby not requiring
the apparatus to be disposed within a reflective chamber.
13. The method defined in claim 12 wherein each of the plurality of coils has
an inner diameter defining an opening, said lamp being positioned within said opening.
14. The method defined in claim 12 wherein the light source is a plurality of
ultraviolet lamps.
15. The method defined in claim 12 wherein the tube is a quartz tube.
16. The method defined in claim 12 wherein the tube is a germicidal glass tube.
17. An apparatus for disinfecting a fluid delivered from a source comprising:
a germicidal glass tube connected with the source for transporting the fluid
from the source to a discharge; and
an ultraviolet lamp positioned adjacent the tube, wherein the lamp is adapted
to transmit light waves through the fluid such that the light waves are transmitted
directly at the fluid within the tube such that the light is dispersed outwardly
from the apparatus such that the light is not reflected back towards the apparatus
except by the tube itself;
wherein the tube has a plurality of adjacent coils forming a helix; and
the space between adjacent coils of the helix is less than the diameter of the
helical tube thereby not requiring the apparatus to be disposed within a reflective chamber.
Description
BACKGROUND OF THE INVENTION
This invention relates to water purification systems. More particularly, this
invention relates to water purification systems incorporating a method for the
exposure of water to ultraviolet light.
It is known to use ultraviolet (UV) radiation to disinfect drinking water. It
is also known that ultraviolet radiation is a means for meeting the bacteriological
requirements of the drinking water standards as enumerated in the Safe Drinking
Water Act (SDWA), 42 U.S.C. §300(f) et seq. (1974). Studies have indicated
that ultraviolet radiation at a level of 2,537 Angstrom units applied at a minimum
dosage of 16,000 micro-watt-seconds per square centimeter at all points throughout
a water disinfecting chamber is adequate to purify water for drinking. It is generally
known to use 30,000 micro-watt seconds per square centimeter to obtain the desired
effect. Using a higher standard helps account for any losses that may occur in
the exposure chamber. If a UV lamp is used that maintains 80% power over 9,000
hours (approximately one year), then setting a standard of 38,000 micro-watt-seconds
per square centimeter would insure that the lamp would require replacement no more
than yearly, while adequately sterilizing the water flow that is exposed to the
UV lamp.
In commonly configured ultraviolet light water purification systems, ultraviolet
light serves the purpose of exposing a fluid to ultraviolet light radiation which
either kills bacteria or renders bacteria unable to reproduce. A straight quartz
fluid tube permits an ultraviolet light source to be inserted in the inside diameter
of the tubing while water is passed over the outside diameter of the length of
the lamp.
One commonly known means of exposing water to ultraviolet light is to place a
light source in a straight quartz tube with water flowing through an outer chamber
past the linear distance of the ultraviolet light source. Such a design generally
requires a pressure cylinder to be built around the lamp-supporting construction.
This also requires that the pressurized cylinder be at the same length or longer
than the provided ultraviolet light source. It would, therefore, be advantageous
to develop an apparatus that can more easily be used to purify water.
SUMMARY OF THE INVENTION
The invention relates to an apparatus for disinfecting a fluid. The apparatus
includes a tube connected to a source of fluid. The tube allows the fluid to be
transported from the source to a discharge. An ultraviolet lamp is positioned adjacent
the tube, and is adapted to transmit light waves through the fluid. The tube can
be a coiled tube having one or more coils thereby forming a helical tube. Each
coil of the helical tube has an inner diameter and an outer diameter. The inner
diameters of the coils define a space or opening. The ultraviolet lamp can be positioned
within the opening. A fluid passing through the coils of the tube are exposed to
the ultraviolet light. The tube can be made of germicidal glass or quartz.
The method of the invention includes moving water from a source to a discharge,
through the tube while the lamp is activated. Water will become disinfected as
it is exposed to the ultraviolet light of the lamp. Due to the shape of the tube,
more water can be exposed to the ultraviolet light in a shorter distance than with
linear tubes.
Various objects and advantages of this invention will become apparent to
those skilled in the art from the following detailed description of the preferred
embodiment, when read in light of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevational view of a helical tube in accordance with the present invention.
FIG. 2 is a plan view of the helical tube shown in FIG. 1.
FIG. 3 is an end view of the helical tube shown in FIGS. 1 and 2.
FIG. 4 is a sectional view of the helical tube through section line 4—4
with a lamp positioned within the helical tube.
FIG. 5 is an end view of the helical tube shown in FIG. 4 with a lamp inserted
within the helical tube.
FIG. 6 is a side elevational view of a water purification apparatus with the
helical tube of the present invention connected to inlet and outlet ports.
FIG. 7 is an end view of the water purification apparatus shown in FIG. 6.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings, there is illustrated in FIG. 1 a side elevational
view of a helical tube indicated generally at
10. The generally transparent
tube
10 is adapted to allow a fluid, such as water, to pass through the
inner surface of the tube
10. Particularly, a fluid can enter from a source
connecting tube
12, pass through the coils of the helix (helical coils)
generally shown at
14, and exit from a discharge connecting tube
16.
Each coil
14a,
14b,
14c,
14d,
and
14e is generally hollow and interconnects to each adjacent coil.
The coils on each end of the tube
10 are also connected to a source
12
and discharge
16 tube. The source connecting tube
12 and discharge
connecting tube
16 can have any shape, such as the hollow, generally cylindrical
shape shown in the Figures. The tubes
12 and
16 are preferably shaped
so that the helical tube
10 can be connected to a source of fluid (not shown)
and a discharge receptacle or an outlet pipe (not shown). The helical coils
14
are shown having an angled pitch, θ. However it is understood that the helix
pitch angle, θ, can be larger or smaller as desired. Also, the helical coils
14 can be wound in the opposite direction. Additionally, as best seen in
FIG. 2, the cross-sectional shape of the connecting tubes
12 and
16
is generally circular. Preferably the connecting tubes
12 and
16
are adapted to fit onto generally conventional piping. However, it should be understood
that the cross-sectional shape of the connecting tubes
12 and
16
can have any desired shape such as generally oval or rectangular.
Illustrated in FIG. 3 is an end view of the helical tube
10 of
the present invention. The helical coils
14 are shown as having a generally
circular shape. Thus, each coil
14a,
14b,
14c,
14d, and
14e, each have an outer diameter and inner
diameter. It should be understood, however, that the helical coils
14 can
also have any desired cross-sectional shape. FIG. 3 illustrates an opening
18
defined by the inner diameters
20 of the helical coils
14 of the
tube
10. The opening
18 is illustrated as having a generally cylindrical
shape, however, it should be understood that the opening
18 can have any
shape or size, and have a non-uniform diameter. For example, the opening could
be cylindrical with the coils
14 having a larger diameter at a first end
and a relatively smaller diameter at a second end. For example, the inner diameter
of coil
14a is larger than
14b. Coil
14b
has an inner diameter larger than coil
14c, and so forth. Thus,
the shape of the opening
18 could be generally conical. Also, although only
six helical coils
14 are illustrated, it can be appreciated that any desired
number of helical coils
14 can be used in the tube
10 as required
with the invention. Generally, with a greater number of helical coils
14,
the overall length of the tube
10 could increase. However, a greater number
of coils
14 could be formed in a similar or smaller area. This could be
done by using smaller diameter coils, or using a smaller helix pitch angle, θ.
Additionally, the spacing between coils
14 could be increased or decreased
as desired to incorporate a greater or fewer number of coils
14 into the
helical tube
10.
Using a helical tube
10 reduces the linear flow requirements of a conventional
straight tube fluid purification system. Fluid flow through a helical tube
10
allows there to be greater exposure of the fluid being carried within the tube
10 to a lamp
22 that is an ultraviolet light source over a shorter
span length. Flow of a fluid through the helical tube
10 reduces the physical
size of the purification unit versus a linear system since more flow can occur
over the same linear distance. Additionally, since the helical tube
10 reduces
the linear flow requirements when compared with straight tube systems, lower wattage
lamps may be used. A shorter linear travel distance for a fluid with a helical
tube
10 allows for the same micro-watts-seconds exposure of the fluid within
a reduced space.
It is preferred that the helical tube
10 be formed from quartz or glass.
It is further preferred that the type of glass used is of a germicidal type. Glass
is typically a poor conductor of ultraviolet light but germicidal glass has improved
conductive qualities. Quartz or glass tubing can also permit the flow of heated
fluids through the tube
10 with a reduced possibility of malformation or
deformation and, therefore, failure of the tube
10. Another benefit of using
helical quartz or glass tubing is that helical quartz or glass tubing can withstand
the pressure requirements of a water purification system. This reduces space and
costs because no outer pressure chamber is required to maintain a relatively higher
system pressure. Also, it is know that quartz has a negligible expansion rate under
the typical conditions of operating the present invention. Therefore, quartz is
a preferred material from which the tube
10 and preferably at least the
helical coils
14 can be made. It can be appreciated, however, that any suitable
material can be used in accordance with the invention as described herein. The
thickness of the quartz helical coils can vary according to the desired design
specifications. The thickness of the quartz wall will typically not affect the
disinfection process. The invention design also allows multiple ultraviolet lamps
22 to be inserted into the opening
18 of the helix thereby increasing
the available ultraviolet wattage within the same physical structure of the entire
water purification assembly, as is described in greater detail below.
Illustrated in FIG. 4 is a cross-sectional view of the helical tube
10
illustrated in FIG.
1. Again, it is shown that the preferred cross-sectional
shape of the helical coils
14 is generally circular. However, the helical
coils
14 can have any shape or size, as described above. Also shown in FIG.
4 is a lamp
22 positioned within the opening
18 of the helical tube
10. The lamp
22 is preferably an ultraviolet light, however, the
lamp can be any type of lighting device that emits any type of radiation that can
be used for the disinfecting of fluids. It is preferred that germicidal lamps be
used since germicidal lamps have a sharply defined spectral output at 253.7 nanometers.
Since this is very close to the wavelength most effective in inhibiting bacteria
and molds, no wavelength correction is necessary. However, it can be appreciated
that lamps can produce ultraviolet light having different wavelengths and be coated
to adjust the wavelength for the optimal ultraviolet wavelength for inhibiting
bacteria growth.
The lamp
22 preferably has electrical leads
24 that can are adapted
to be connected to a source of electrical power (not shown). The source of electrical
power, when activated, energizes the lamp
22 causing ultraviolet light to
be emitted therefrom. In an alternate embodiment, the lamp
22 can have a
power connection or electrical leads
24 at both ends, or at some other location
along the length of the helical tube
10. Alternatively, a single-ended ultraviolet
lamp (a lamp having electrical connections at only one end) could also be used.
Illustrated in FIG. 5 is an end view of the helical tube
10 with
the lamp
22 positioned within the opening
18 of the tube
10.
The lamp
22 is preferably centrally positioned within the opening
18
such that a generally equal amount of radiation is applied in all directions. However
it is understood that the lamp
22 can be positioned off-center and still
apply radiation to the helical coils
14. The lamp
22 illustrated
is also shown as having a smaller diameter than that of the opening
18.
It should be appreciated that the lamp
22 can have a larger or smaller diameter
than illustrated. However, the diameter of the lamp
22 is preferably such
that the lamp
22 can be positioned within the opening
18 of the helical
tube
10. Alternatively, with a lamp
22 having a diameter that is
smaller than the opening, a plurality of lamps
22 can be positioned within
the opening
18 of the tube
10. If a plurality of lamps
22
are positioned within the opening
18, it is preferred that the lamps
22
be evenly spaced within the opening
18. However, the lamps
22 can
be positioned closer or farther apart or randomly positioned within the opening
18.
Now referring to FIG. 6, a water purification apparatus
30 including the
helical tube
10 described above is illustrated. In commonly configured ultraviolet
light water purification systems, ultraviolet light serves the purpose of exposing
a fluid, preferably water, to ultraviolet light radiation which either kills bacteria
or renders bacteria unable to reproduce. A straight quartz tube permits an ultraviolet
light source to be inserted in the inside diameter of the tubing while water is
passed over the outside diameter of the length of the lamp. Such flow is typically
understood to be laminar flow. Laminar flow is classically defined as a well ordered
pattern of flow whereby fluid layers are assumed to slide over one another. Utilizing
tubing formed into a helical shape induces turbulence in the flow of the water.
Turbulent flow is irregular or unstable flow. Because the flow is turbulent, more
of the water is exposed to the ultraviolet light source. Additionally, more water
is exposed to the light source without reducing the conductivity of the light waveforms.
The illustrated helical tube apparatus
30 has a plurality of ultraviolet
lamps
22 positioned within the opening
18 of the tube
10.
A portion of the helical coils
14 are shown with a section of the coils
14 removed so as to illustrate the general position of the lamps
22
within the opening
18. As best shown in FIG. 7, three lamps
22 are
illustrated as being positioned within the opening
18. However, it should
be understood that a greater or fewer number of lamps
22 can be used. Additionally,
the positions of the lamps
22 can be different than those shown in the Figures.
Each lamp
22 is positioned so that the electrical leads
24 are positioned
on the same side of the opening
18 within the tube
10. However, the
leads
24 can be positioned in any manner so that the leads
24 of
the lamps
22 can be connected to a source of electricity.
Illustrated in FIG. 7 is the water purification apparatus
30 of
the present invention. The source connecting tube
12 of the apparatus
30
is received within an adapter
34 so that a fluid source (not shown) can
be connected to the helical tube
10. The adapter
34 can include conventional
pipe threads at a second end and a compression ring and cap assembly
32
at a first end. The source connecting tube
12 can be received within the
first end of the adapter
32. When the cap
32 is tightened, the compression
ring (inside the cap
32) forms a seal with the source connecting tube
12.
At the other end of the adapter
34, a conventional pipe, tube, or hose (not
shown) can be connected by threading it onto the pipe threads. The discharge connecting
tube
16 is similarly connected via an adapter
36 to a discharge chamber
(not shown). It should be understood that the helical tube
10 can be adapted
to connect to a source and discharge by any means. However, with the compression
ring apparatus
34 and
36, it is preferred that the source connecting
tube
12 and discharge connecting tube
16 are circular in cross-sectional
shape. The discharged fluid can be collected from the chamber or transferred to
another collection area. For example, the fluid can be piped for further processing,
be bottled, or stored for any other use where purified water is desired.
Although a helical tube has been illustrated as the preferred embodiment,
it can be appreciated that a transparent, linear tube could also be used without
departing from the scope of the invention. Particularly, a light source could be
positioned adjacent a tube that transports a fluid. Activation of the lamp while
fluid is flowing through the pipe causes ultraviolet light to disinfect the fluid.
In accordance with the present invention, wherein increased flow using the same
or less amount of space and energy is desired, a plurality of transparent, linear
tubes could be positioned adjacent the same lamp. Thus, a single lamp surrounded
by a plurality of fluid tubes causes the fluid passing through each of the tubes
to be acted upon by the light emitted. Alternatively, a lamp could be positioned
adjacent a tube, wherein the tube is curved, but only extends in a single plane,
similar to a radiator. When the fluid passes through the tube, the lamp acts on
the fluid throughout the length of the tube. The lamp could be a "flat panel" lamp,
or could be multiple linear lamps positioned in a row.
Although the illustrated water purification apparatus is horizontally oriented,
it can be appreciated that the apparatus can also be mounted vertically, or at
any desired angle, with the input and output ends adjusted accordingly. Additionally,
although the invention has been described as using ultraviolet light to disinfect
a fluid, it can be appreciated that any source of electromagnetic radiation could
also be used in accordance with the invention.
In accordance with the provisions of the patent statutes, the principle and mode
of operation of this invention have been explained and illustrated in its preferred
embodiment. However, it must be understood that this invention may be practiced
otherwise than as specifically explained and illustrated without departing from
its spirit or scope.
*
