U.S. patent number 3,602,712 [Application Number 04/799,578] was granted by the patent office on 1971-08-31 for fluid irradiating apparatus using gamma rays and helical passageways.
This patent grant is currently assigned to Energy Systems, Inc.. Invention is credited to Leland A. Mann, David D. Woodbridge.
United States Patent |
3,602,712 |
Mann , et al. |
August 31, 1971 |
FLUID IRRADIATING APPARATUS USING GAMMA RAYS AND HELICAL
PASSAGEWAYS
Abstract
A radioactive apparatus is provided for the sterilization and
treatment of liquids and especially for the sterilization and
treatment of liquid waste such as sewage and industrial waste by
the use of gamma radiation sources. A spiraling input chamber
spirals around a center chamber having an elongated core member
with a helical pipe forming a helix or coil around said hollow
member in the center chamber. Liquid waste being received by the
apparatus passes through the spiraling chamber into the center
chamber, into and through the elongated hollow member and then
through the helical pipe to an output. Gamma radiation sources are
located around the helical pipe in such a manner as to provide an
efficient use of the radiation sources.
Inventors: |
Mann; Leland A. (Brevard,
FL), Woodbridge; David D. (Brevard, FL) |
Assignee: |
Energy Systems, Inc.
(Melbourne, FL)
|
Family
ID: |
25176248 |
Appl.
No.: |
04/799,578 |
Filed: |
February 17, 1969 |
Current U.S.
Class: |
378/67; 250/436;
250/438; 250/437; 976/DIG.441 |
Current CPC
Class: |
G21K
5/02 (20130101); C02F 1/30 (20130101) |
Current International
Class: |
C02F
1/30 (20060101); G21K 5/02 (20060101); G21h
005/00 () |
Field of
Search: |
;250/43,48,49,52,106,44 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Borchelt; Archie R.
Claims
We claim:
1. An irradiator apparatus for irradiating fluids comprising in
combination:
a. input and output means for receiving and discharging fluids;
b. a plurality of passageways connected in series between said
input and output means and being adapted for the continuous passage
of fluids from said input means through each said passageway and
out said output means;
c. baffle means located in at least one said passageway for
baffling fluid passing through said passageways;
d. one said passageway being an elongated tubular center core
surrounded by each of said other passageways and having two end
portions, with at least one opening in each said end portion
adapted for receiving fluid in one said end portion and discharging
said fluid from the other said end portion;
e. a plurality of parallel gamma radiation sources surrounding said
center core passageway, said plurality of gamma radiation sources
being surrounded by at least one of said other plurality of
passageways whereby fluids passing through said irradiation
apparatus will be substantially uniformly irradiated.
2. The apparatus according to claim 1 in which a second said
passageway is connected to said center core passageway at one end
portion thereof and to said output means and forming a helix around
said center core.
3. The apparatus according to claim 2 in which a third passageway
is connected to said center core passageway and to said input
means.
4. The apparatus according to claim 3 in which said radiation
sources form two circular parallel rows around said center core,
one said row being located on the outside of the helix formed from
said second helical passageway.
5. The apparatus according to claim 4 in which said center core
passageway has baffles means located therein.
6. The apparatus according to claim 5, in which said third
passageway has baffles therein.
7. The apparatus according to claim 6 in which the baffles in said
center core passageway have plate baffles with openings passing
therethrough alternating with solid plate baffles, said baffles
being fixedly attached to said center core and to each other.
8. The apparatus according to claim 7 in which said radiation
sources are elongated cylindrically shaped.
9. The apparatus according to claim 8 in which said gamma radiation
sources are cobalt 60.
10. The apparatus according to claim 9, in which said third
passageway is a spiralling helical pipe.
11. The apparatus according to claim 10, in which said radiation
sources are contained in radiation-holding means adapted to be hung
on said second helical passageway.
12. The apparatus according to claim 10, in which said radiation
sources are contained in holding means attached to said center
member and to the wall of said center chamber.
13. The apparatus according to claim 7, in which said gamma
radiation sources are cesium 137.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to radioactive devices and
particularly to radioactive devices for sterilizing and treating
liquids and especially liquid waste such as sewage and industrial
waste. The present irradiator provides a relatively high efficiency
utilization of its gamma radiation sources to kill micro-organisms
and to break down the molecular structure of components of the
waste.
2. Description of the Prior Art holding pressure, to for
microbiological
In the past various types of irradiators and sterilizers have been
suggested for liquids and especially for disinfecting water. These
prior art sterilizers frequently involved the use of heat by
holding the temperature, and sometimes the pressure to an elevated
degree for a predetermined length of time to obtain a substantial
kill as desired of the microbiological agents in the liquid.
It has also been suggested in the past to use various types of
radiation for the sterilization of liquids as well as for the
sterilization of foods, drugs and the like.
The treatment of liquids by these prior art radiation means is
frequently carried out by circulating the fluids through tubes
having walls transparent to radiation, through which walls the
radiation will pass, with the radiation source located next to the
wall. Ultraviolet light has been one of the most common types of
radiation use for the sterilization of liquids, and the like, and
in this type of radiation as in many others, the tubes of the
radiation sources may become coated with solid materials such as
contaminations in the liquid, or the transparency of the liquid may
be low, thus reducing the efficiency of the sterilization. This is
particularly true with the use of ultraviolet radiation and the
like. Such coatings and/or suspended materials have negligible
effect on the effectiveness of the present invention.
Finally, it has been suggested to use radioactive isotope sources
for the sterilization of liquids as well as for gases and solids.
This type of sterilizer has proved advantageous over heat
sterilizers because of the time saved in the rapid sterilization by
radiation by avoiding the time lost during the thermodiffusion
period and for other reasons. One such radiation sterilizer
provides two sets of pipes alternately wrapped around a radiation
source and encompassed within a lead shielding contained so that
two separate liquids may be irradiated simultaneously. While this
prior art device has certain advantages, it is not suitable for the
treatment of liquid waste because of the small tubes used without
means for keeping solid particles of contamination intermixed with
the fluid. It also loses a great deal of efficiency by irradiating
on only one side of the source and by useless absorption of large
amounts of radiation in metal walls, and is adapted only for use
with a single source. The present invention, on the other hand,
provides for the irradiation of a very large volume of liquid which
will normally have varying amounts of solids in various forms and
sizes mixed within the liquid. It also provides a relatively high
efficiency for use of the energy of the radiation source and
improved flow control for the liquid passing into and out of the
irradiator.
SUMMARY OF THE INVENTION
The present invention is a liquid irradiator utilizing gamma
radiation sources for the sterilization and treatment of liquids,
especially liquid waste such as sewage and industrial waste in
which large volumes of liquids need to be treated and which liquids
may commonly have various amounts and types of solid matter
therein. The irradiator has a hollow center chamber and a
spiralling input chamber for receiving the entering flow of liquid
to spiral around the center chamber and to flow into the center
chamber from the spiralling input chamber at one end thereof. The
liquid then passes through the center chamber, and into an
elongated core member located in the center chamber, out a pipe
which is helically wrapped around the hollow member, prior to
exiting from the irradiator. Gamma radiation sources are located in
the center chamber and around the elongated core member and may be
desirably placed in two parallel circles, one on each side of the
helical exit pipe. Baffles may be appropriately located throughout
the system for increasing the turbulence in the fluid to improve
uniformity of radiation close to the liquid and prevent settling of
any solids therein. The irradiator is of course enclosed in
shielding sides which may be, for instance, concrete walls of the
appropriate sides. Inlets and outlets through the shielding will be
curved or bent to prevent escape of any significant quantity of the
radiation, which radiation travels in a straight line and would not
therefore be able to escape. For the same reason, the cover for the
shielding chamber would be stepped in the usual manner.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, features, and advantages of this invention will be
apparent from a study of the written description and the drawings
in which:
FIG. 1 is a top plan view with a portion broken away of a preferred
embodiment of the present invention.
FIG. 2 is a view taken along line 2--2 of FIG. 1.
FIG. 3 is a view taken along line 3--3 of FIG. 2.
FIG. 4 shows a broken-away view of the embodiment of FIGS. 1
through 3.
FIG. 5 illustrates a baffle in the elongated core member taken
along line 5--5 of FIG. 4.
FIG. 6 illustrates a second baffle of the elongated core member
taken along line 6--6 of FIG. 4.
FIG. 7 shows a radiation source holder or hanger for the embodiment
of FIGS. 1 through 6.
FIG. 8 is a view taken along line 8--8 of FIG. 7.
FIG. 9 illustrates a second embodiment of the present invention;
and
FIG. 10 illustrates a second embodiment for a radiation-source
holder.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a copy illustrating the location of a loading pool 10
which is not a permanent part of the irradiator but may be used in
loading and unloading the irradiator core. The sterilizer has a
concrete shielding 11, an inlet pipe 12, an exit pipe 13, for the
ingress and egress of liquid respectively. The sterilizer has a
cover 14 which may be a shielding material such as concrete or may
be a heavier material such as lead, or the like. This cover would
normally be stepped, as shown by the dotted lines 15 to prevent the
escape of radiation and will have brackets 16 for placing the cover
on as well as moving it during loading and unloading
operations.
FIG. 2 is taken along lines 1--2 of FIG. 1 and shows a cutaway of
the concrete shielding 11, inlet pipe 12 and exit pipe 13. Step 15
for the cover 14 is more clearly illustrated in this view, as is
bracket 16 and bracket anchors 17 which more readily adapt bracket
16 for lifting the heavy cover.
Referring now to FIG. 3, a cutaway view taken along line 3--3 of
FIG. 2 is shown with the details of the core of the irradiator more
clearly shown. The input 12 and exit 13 pipes can be seen with the
input feeding into an inwardly spiralling chamber 20, having walls
21 and baffles 22. Chamber 20 allows the input liquid to gradually
move in toward the radiation source, with the radiation getting
more intense as the liquid moves through the spiralling chamber.
This chamber is illustrated as circular in cross section, but could
of course be oblong, square or irregular-shaped without departing
from the spirit and scope of the present invention. Baffles 22
provide turbulence to improve the mixing of the liquid, to keep
solid matter mixed within the liquid and to provide better flow
characteristics of the liquid, as well as more uniform irradiation
of the liquid. As the liquid in chamber 20 approaches the end of
the spiralling chamber 23, it is forced through a passage 19 (FIG.
4) into a center chamber 18 and into an elongated member 24. Member
24 has a series of concentric alternating baffles 25 and 26,
baffles 25 being connected to the side of center member 24 with
openings in the center thereof. Baffles 26 on the other hand are
circular members connected to baffles 25 by baffle-holding rod 29.
This baffling system of intermittent baffles not only provides for
turbulence and thorough mixing of solid matter in the liquid, but
also forces the liquid near the walls of center member 24 at
various points as it passes through, as will be described in more
detail later. The liquid exits from core member 24 at 27 into a
helical pipe 28 which wraps in a helix around center member 24 and
exits at exit 13. Helical pipe 28 is illustrated as being circular
in cross section but could, of course, be square, rectangular or
any other shape without departing from the spirit and scope of this
invention. The sources of gamma radiation 30 are placed in a circle
around center member 24 and a second group of sources of gamma
radiation sources 31 may be placed around center member 24, but
further out so that they also encircle the helix formed by pipe 28.
These sources of radiation 30 and 31 may be pencil-shaped, cobalt
60 or cesium 137, but it is to be understood that other shapes and
sources of radiation may be used without departing from the spirit
and scope of the present invention. However, the pencil or
elongated cylinder shape is one form in which cobalt 60 is
commercially available, thus making it a desirable source because
of its availability and reasonable price in this particular shape.
Radiation-source hangers 32 are adapted to have holders attached
thereto which the radiation sources may be placed in. These hangers
are illustrated as being hung on pipe 28, but will be described in
more detail later.
Referring now to FIG. 4--a broken view taken along line 44 of FIG.
1 is shown, having input 12, exit 13, and spiralling chambers 20,
with chamber wall 21. Member 24 and chamber 18 can be more clearly
seen as can baffles 25 and 26, and baffle-holding rods 29. The
liquid leaving chamber 20 through passageway 19 and flowing into
chamber 19 will enter the top portion of member 24 and will flow
therethrough in a turbulent manner because of the baffles 25 and
26, but all of the liquid will be forced near the walls of member
24, very close to radiation sources 30. Upon reaching the bottom of
member 24, the liquid will be forced into pipes 28 at entrance 27
and will be circulated in a helical path between radiation sources
30 and 31, and will flow out exit 13. A set of braces 39 may be
used to maintain pipe 28 at the proper angle of the desired helix.
Source-hanging rods 32 with source holder 33 attached thereto and
holding sources 31 and 30 may also be seen, as can shielding
11.
FIGS. 5 and 6 are taken along lines 5--5 and line 6--6 respectively
of FIG. 4, and illustrate more clearly the baffles in member 24.
FIG. 5 illustrates the center baffle member 26 held by holding rods
29 which are in turn connected to baffle members 25, but do not
directly touch center core member 24, while FIG. 6 shows baffle
plate 25 directly connected to elongated member 24 and also to
baffle-holding rods 29.
FIG. 7 illustrates one type of hanger 32 for holding sources 30 and
31. The rods of hanger 32 have containers 33 connected thereto for
holding the sources while a plate 35 is attached to the rods and
has an aperture 36 whereby a pair of sources may be removed with a
hook or other mechanical means for handling the source in a safe
manner.
FIG. 8 shows a view along line 8--8 of FIG. 7 and shows a source
30, source container 33, rod 32, and shows container 33 connected
to rod 32 by weld 36.
Turning now to FIG. 9, there is shown a second embodiment of the
present invention in which most of the features of the invention
remain the same but in which the spiralling chambers have been
replaced by a large pipe and in which the source holders used are
of a different type. Liquid to be irradiated is received at the
input 12 through shielding 11, which as explained may be concrete
but if the structure is to be beneath the earth, earth embankments
would also provide adequate shielding if sufficiently thick. The
liquid enters relatively large pipe 40 and proceeds in a circular
manner forming first an outer and downwardly proceeding helix and
then an inner upper proceeding helix in an outer section 41
separated from an inner section by wall 42. At the finish of the
double helix the liquid enters an elongated center member 24 at 43.
Center core 24 may be the same as described in the earlier
embodiment. The liquid then proceeds through center member 24 and
exits at 27 into pipe 28 which then encircles center member 24 as
already described, prior to exiting at output 13. Inner source
holders 44 are connected to center member 24 by brackets 45 and
outer source holders 46 are connected to wall members 47 by
brackets 48. They will be described in more detail in connection
with FIG. 10. As can be seen at this point, entering liquid
gradually proceeds towards the center core and then back through
the radiation sources so that the liquid is being continuously
radiated as it passes through the irradiator.
FIG. 10 shows a more detailed view of radiation holder 44 and
bracket 45; radiation source 30 may also be seen, which may be an
elongated cylinder-shaped source of cobalt 60, or the like, and
holder 44 may have funnel-shaped opening 46 to provide for easier
loading of the source 30. Since this type of holder is not readily
adaptable to remove the holder, the source would normally have to
be removed separately if this were required for any reason.
However, it is anticipated in the present invention the entire
irradiator will be loaded prior to having its concrete overhead
shielding top put in place and will require no further entry until
the sources must be replaced at which time the radiation source
containers would be removed, reloaded and replaced.
As will be clear to those skilled in the art, an irradiator or
device has been provided for irradiating liquids, especially liquid
waste such as sewage effluent, and the like, and which acts to kill
micro-organisms and to break down contaminants such as detergents,
herbicides and pesticides. In the case of detergents, it has been
found that they can be broken down whether they are biodegradable
or not in most cases, thus simplifying the overall treatment
process.
It is contemplated that other embodiments are within the scope of
the invention and such embodiment might for instance include a pair
of concentric tubes surrounding and parallel to the center member
and being baffled so that liquid leaving the special chamber will
pass vertically between the baffled tubes up through one and down
the next. This would of course replace the helical pipe means and
would include additional baffles.
This invention is not to be construed as limited to these
particular forms disclosed herein since these are to be regarded as
illustrative rather than restrictive.
* * * * *