Note: Descriptions are shown in the official language in which they were submitted.
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SPRAY NOZZLE AND A PROCESS USING THIS NOZZLE
BACKGROUND OF THE INVENTION
The present invention relates to a dual feed injector comprising two
spray nozzles housed concentrically in a compact nozzle body with an inner
spray
nozzle supplying a full divergent cone spray and an outer spray nozzle
supplying a
hollow divergent or convergent cone spray, and, more particularly, to a method
of
contacting materials with a broad flow range of fluid discharged from the dual
feed
injector.
Spray nozzles may be classified as pressure nozzles, rotating nozzles
and gas-atomizing nozzles. Spray nozzles are used for atomizing a liquid into
droplets and are well known in various applications. For example, U.S. Patent
3,717,306 describes a nozzle for mixing and spraying foam resin components and
is
made up of two concentric spray nozzle members defining a central.path and a
cylindrical path concentric to the central path. Communicating passages
therein are
arranged so that material in the nozzle is given a swirling motion for good
mixing
and then the mixture is discharged in a single spray cone.
A single spray nozzle can effectively spray over a limited flow range.
For effective use of sprays in confined spaces, there is a need to spray over
a broad
flow range. The present invention meets this need.
SUMMARY OF THE INVENTION
According to the invention there is provided a dual feed injector
comprising:
(a) an outer spray nozzle having an outer fluid supply line
communicating with a means for determining an angle of a spray from about 10
degrees to about 90 degrees,
said outer nozzle terminating with an annular orifice far supplying a
hollow divergent or convergent cone spray;
(b) an inner spray nozzle having an inner fluid supply line
communicating with a means for determining an angle of a spray from about 10
degrees to about 90 degrees,
said inner nozzle terminating with a central orifice for supplying a full
divergent cone spray; and
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(c) means for atomizing a fluid near a tercTtinal end of the outer and
inner nozzles,
said inner and outer nozzles being disposed concentric to each other
and housed in a compact nozzle body.
~RI,~,~F D~~", .RIPTION OF'1',~F.~RA
Fig. IA and Fig. IC are a side view and top view, respectively, of the
dual feed injector of this invention.
Fig. 1B is an end view of the dual feed injector of this invention.
Fig. 2 is a longitudinal cross sectional view of the dual feed injector of
1S this invention.
DETAILED DESCRIPTI01~1 OF THE INVENTION
The dual feed injector of this invention is uniquely capable of
providing two streams of atomized fluid within a broad flow range for good
contacting between a fluid discharged from the dual feed injector and a fluid
in a
. vessel, pipe or the like. The dual feed injector is especially applicable
for rapidly
cooling an effluent gas stream in a confined space from about
800°C.1500°C down to
about 200°C-550°C. Rapid cooling from about 900°C-
1000°C down to about
450°C-SSa°C is preferred.
Illustrative of such a process is chlorinating ferrotitaniferous materials
and separating titanium tetrachloride as described in greater detail in U.S.
Patent
3,261,664 and U.S. Patent 4,066,424, the teachings of which are incorporated
herein
by reference. Hot chlorination gases produced from the reaction are primarily
titanium tetrachloride, ferric chloride and ferrous chloride. These gases are
passed
to a transfer duct whereby a single spray injection nozzle introduces a liquid
coolant,
e.g., liquid titanium tetrachloride to perform the essential step of
contacting and
cooling the hot chlorination gases to about 450°C to about
550°C. The dual feed
injector of this invention is an improvement over this single spray injection
nozzle.
Referring now to Fig. 1B, the dual feed injector end view shows the
3S tangential entry 30 of the fluid supplying the outer nozzle 10. The
tangential entry
30 contributes to the flow and spray pattern of the fluid. It will be
appreciated by
those skilled in the art chat depending upon the particular application, the
entry can
be tangential or concentric. Referring now to Fig. 2, the inner spray nozzle
20
terminates with a central orifice 8 which discharges a full divergent cone
spray. Full
divergent cone spray is defined herein to refer to small particles or droplets
forming
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a substantially whole conical region fanning outward. The outer spray nozzle
10
terminates with an annular orifice 9 which discharges a hollow divergent or
convergent cone spray. Hollow divergent or convergent cone spray is defined
herein
to refer to small particles or droplets forming a ring shape around a
perimeter of a
circle fanning outward or merging towards the full divergent cone spray. The
inner
nozzle feed 1 and outer nozzle feed 2 are typically fed from different sources
of the
same liquid. The feed can be simultaneous or sequential. In an alternative
embodiment the inner nozzle feed 1 and outer nozzle feed 2 may be fed from the
same source or with different fluids. Further, two liquids may be contacted
with a
third liquid and slurries or pastes can be extruded through the outer spray
nozzle
for contact or tre.atmeni with other fluids. The dual feed injector of this
invention
can be used for many processes or purposes, including but not limited to,
atomizing,
cooling, heating, chemically reacting, mixing, evaporating, spray drying,
contacting
or treatitig. Combinations of the foregoing can be used.
Upstream from a mounting flange 5, the fluid then enters a concentric
or tangential outer fluid supply line 3 supplied from outer nozzle feed 2 and
a
concentric or tangential inner fluid supply line 4 supplied from inner nozzle
feed 1.
For industrial applications or processes, the fluid flow ranges and pressure
ranges
can be readily determined for the desired application or process. For example,
in
cooling an effluent gas stream, the fluid flow range in the inner nozzle can
be a high
flow range, e.g., about 100 to about 600 gallons per minute at a pressure of
about 1
to about 90 psig. The outer nozzle can be a low flow range, e.g., about 20 to
about
200 gallons per minute at a pressure of about 1 to about 60 psig. The outer
fluid
supply line 3 and the inner fluid supply line 4 communicates with a means for
determining an angle of the spray 6a, 6b, 7a and 7b. For example, stationary
turning
vanes 6a and 6b can provide a swirling motion. The swirl of the fluid in turn
and,
in conjunction with a decreased diameter 7a and 7b near the terminating end of
the
inner and outer nozzles, determine the angle of the spray. Spray angle may
range
from about 10 to about 90 degrees but may be selected based on the particular
application with 15, 30 and 60 degrees being common. When the confined space
is a
relatively narrow pipe, the angle of the spray should be minimized if it is
desirable
to virtually avoid the spray impinging on the pipe wall. The direction of the
jet of
fluid can be at any angle relative to the direction of flow of the gaseous
mixture, e.g.,
counter current or corurrent. Counter current flow is preferred in cooling an
effluent gas since it promotes rapid cooling and complete evaporation of the
liquid
coolant. Near the terminating end, the inner nozzle diameter 7a and the outer
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nozzle diameter 7b decrease and the volume available for the fluid l7ow also
decreases. The change in the available volume also provides the energy needed
to
atomize the fluid, or break it up into many small particles or droplets. It
has been
observed that smaller particles or droplets provide better contacting when
cooling
an effluent gas. The dual feed injector can be designed for any given droplet
size.
In a process for cooling an effluent gas stream, it may be desirable for the
mean
liquid spray droplet diameter to be in the range of about 0.2 to 20 mm. It
will be
appreciated by those skilled in the art that depending upon the different
industrial
application or fluid being fed through the dual feed injector that operating
parameters, vane configuration. and dimensions may be readily determined by
constructing a model dual feed injector and testing the operating parameters,
vane
configuration and dimensions for the desired flow range and spray pattern. By
ways
of example and not limitation, the dimensions suitable for cooling an effluent
gas
can be an'overall length of about 2b" long. The overall height can be about
15.25", i
The upstream inner diameter of the outer nozzle can be about 5.75" and the
upstream inner diameter of the inner nozzle can be about 2.9". -The diameter
then
reduces near the terminal end wherein the reduced diameter 7a of the inner
nozzle
can be about 1.5". The reduced diameter 7b of the outer nozzle can be about
2.2"
and the width of the annular orifice can be about 0.3".
The dual feed injector can be constructed of any material that is
suitable for the fluid being fed through it. Typically, a stainless steel
alloy will be
appropriate for most applications but a more corrosion resistant material such
as
Hastelloy~ can be used.
The present invention provides greater efficiency and process
flexibility than found in conventional spray nozzles and has wide
applications. The
dual feed injector combines compactness with the ability to produce an
excellent
spray pattern over a much larger range of flow rates than a conventional
nozzle.
-~ The terms and expressions which have been employed are used as
terms of description and not of limitation, and there is no intention in the
use of
such terms and expressions of excluding any equivalent of the features shown
and
described or any portion thereof, but it is recognized that various
modifications are
possible within the scope of the appended claims.
