Fluid-solids contact device and improved fluid distributor

A fluid-solids contacting device is provided in tanks which can be essentially filled with particulate solids treating medium. An improved fluid distributor element is provided in such vessels including a tube-defining-frame such as a helix which is anchored to a fluid inlet or outlet pipe and which is covered with a fabric sleeve secured annularly to the pipe end. Where the pipe is an inlet pipe, all of the fluid must flow through the sleeve and is distributed over the area of the sleeve within the fluid-solids treating vessel. Where the pipe is an outlet pipe, the fluids leaving the tank must pass through the sleeve before entering into the outlet pipe. In both cases the flow distribution of the fluid within the tank is improved.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to fluid-solids contact devices wherein a fluid (gas 
or solid) is contacted with particulate solids in a tank to effect a 
change in the composition of the fluid. More particularly, the invention 
concerns such fluid-solids contacting devices having an improved fluid 
distributor. 
2. Statement of the Prior Art 
Fluid-solids contacting devices are well known wherein a gas or liquid is 
contacted with particulate solids for the purpose of altering the 
characteristics of the gas or liquid. Typical examples for gas contacting 
include: cleaning exhaust airstreams by removing contaminants; cleaning 
storage tank vent gases; process vents; treating sewage gas vent streams; 
treating laboratory hood exhaust streams; treating the exhaust gases from 
vacuum pumps; dehydrating gaseous streams, particularly airstreams. For 
these gas-solids contact devices, the treatment solids may be particulate 
activated carbon; silica gel; activated alumina; ion exchange resins; 
various coalescing fibrous solids and the like. 
Typical liquid-solids contacting installations include: sewage treatments; 
industrial waste waters; solvent streams; laboratory waste streams; 
separator runoff streams; scrubber wastes; plant and transportation 
spills; electroplating baths; recycled water; potable water; wash water. 
The particulate solids may be activated carbon; silica gel; activated 
alumina; molecular sieves; ion exchange resins; coalescing fibers. 
Disposable or rechargeable devices are known wherein a tank, frequently a 
conventional metal drum (e.g., 55 gallons capacity) is employed as a tank 
for the particulate solids. The fluid (gas or liquid) is introduced and 
required to pass through a bed of the particulate solids for treatment. 
The treated fluid is recovered at the other end of the bed of particulate 
solids as a fluid stream. According to the prior art, such tanks employ a 
distributor plate in some cases to support the particulate solids bed and 
in other cases employ a supporting bed of inert solids such as gravel or 
sand to serve as a fluid distributing member to distribute the impact 
velocity component of the inlet fluid or withdrawn fluid. 
The use of such distributor plates and supporting inert solids beds 
restricts the inventory of particulate solids which can be maintained in 
the tank. Hence such device must be replaced or recharged frequently. The 
recharging of such tanks is a cumbersome operation since the perforated 
membrane must be cleaned and reinstalled; or the inert solids must be 
discarded, or removed, cleaned, recovered and replaced. All of the prior 
art disposable or rechargeable fluids-solids contacting devices would be 
improved by minimizing channeling within the bed of particulate solids. 
Accordingly there is a need for an improved fluid-solids contact device 
which has a longer operating life and hence requires fewer replacements. 
There is a need for a fluid-solids contact device with improved fluid flow 
distribution and accompanying reduction in the fluid pressure drop through 
the solids bed. 
A fluid-solids treatment device which can be easily refilled without 
requiring special treatment of screens or inert solids is desirable. 
STATEMENT OF THE INVENTION 
According to this invention an improved fluid-solids treatment device is 
provided which can be assembled in any convenient tank, preferably a metal 
barrel. The essence of the invention is an improved fluid distributor 
which is fabricated from a helical wire or other tube-forming-frame which 
is anchored to a pipe end and is surrounded by a sleeve of fabric, 
preferably woven metal fabric which is secured annularly to the same pipe 
end. When the pipe end is an inlet pipe end, all of the fluids entering 
the tank through the inlet pipe end must pass through the sleeve of fabric 
which is positioned over the base of the tank. The incoming fluid thereby 
is uniformly dispersed throughout the base of the tank. This type of inlet 
is particularly useful where the fluid undergoing treatment is gas. In 
such installations the tank has an inlet as its bottom end containing the 
described fluid distributor. The fluid outlet is provided at the top of 
the tank above the solids bed. Inasmuch as the tank is completely filled 
with the treating solids except for the modest space taken up by the fluid 
distributor, the solids inventory is increased. 
In another embodiment, the fluid distributor is secured to the outlet of a 
fluid-solids treatment device. Such installations are particularly useful 
when the fluid is a liquid. In such installations, a fluid inlet is 
provided at the top of the tank and the fluid outlet is provided at the 
bottom of the tank. The fluid distributor is secured to the outlet pipe. 
Any fluids leaving the tank must pass through the sleeve and thence into 
the outlet pipe.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIG. 1 there is illustrated a tank 10 which is prefereably a 
metal drum of 55 gallon capacity although other size metal drums may be 
employed. The tank 10 has a bottom inlet pipe 11 and a top outlet pipe 12. 
The inlet pipe 11 is connected to a fluid distributor 13. The tank 10 is 
otherwise filled with a bed 14 of particulate solids which are the 
treatment medium for the fluid which is introduced into the tank through 
the inlet 11. The installation illustrated in FIG. 10 is particularly 
useful for treating gases with solids. A gas to be treated is introduced 
into the inlet 11 and is distributed through the fluid distributor 13 
essentially uniformly across the base of the tank 10 whence it rises 
upwardly through the particle bed 14. In traversing the bed 14, the gas 
loses its contaminants which remain behind in the particle bed 14. A 
cleaned gas stream is recovered through the outlet pipe 12. 
In the alternative embodiment illustrated in FIG. 2, a tank 20 has an inlet 
21 at the top of the tank and an outlet pipe 22 at the bottom of the tank. 
The outlet pipe 22 is connected to a distributor device 23 similar to the 
device 13 of FIG. 1. The remainder of the tank 20 is filled with a bed 24 
of particulate solids which are the treating medium for the fluid which is 
introduced through the inlet 21. In this embodiment, which is particularly 
useful for treating liquid streams, the fluid is introduced through the 
inlet 21 into the tank 20 and descends through the particle bed 24 for 
recovery through the distributor member 23 and ultimate withdrawal from 
the tank through the outlet pipe 22. As illustrated in FIG. 2, the outlet 
pipe 22 is connected to a vertical riser pipe 25. 
While the drums 10, 20 are shown in an upright position in FIGS. 1 and 2, 
horizontal drums also may be employed in the present fluid-solids 
contacting device. 
In similar prior art fluid-solids contact devices, the bottom portion of 
the tank 10, 20 might be filled with inert particles such as gravel to 
provide for the distribution of fluids. The provision of a suitable base 
bed of inert particles reduces the inventory of active treatment solid 
particles in the particle bed 14, 20. In other prior art devices a 
foraminous support such as a screen or perforated plate is provided within 
the tank 10, 20 at a level above the inlet 11 (FIG. 1) or outlet 22 (FIG. 
2) to establish uniform flow patterns and to retard channeling within the 
treatment bed. Those prior art devices similarly had a reduced inventory 
of active solid particles in the treatment beds. Such foraminous supports 
also are relatively costly. 
The fluid distributor according to this invention is assembled as shown in 
FIG. 3. A pipe end 30 has a small detent or hole 31. A wire helix 32 has a 
hook 33 at one end for engagement in the hole 31 to anchor the helix 32 
with respect to the pipe end 30. A wire fabric sleeve 34 is positioned 
outside the wire helix 32 and engages at its open end the outer surface of 
the pipe end 30. An appropriate pipe clamp 35 is applied over the open end 
of the sleeve 34 to clamp the sleeve to the outer surface of the pipe end 
30. The other end of the sleeve 34 is closed. Preferably the wire fabric 
is folded and the folds are fastened with some form of a fastener, 
preferably a penetrating fastener such as a rivet 36, stitches, staples 
and the like. The wire helix 32 has a diameter which corresponds to the 
outer diameter of the pipe end 30. The wire helix 32 functions as a 
tube-defining-frame to support the tubular shape of the fabric sleeve 34. 
Any fluids entering into the inlet pipe 30 will fill the sleeve 34 and 
pass out through the openings in the fabric which forms the sleeve 34. 
The term "fabric" as employed herein comprehends woven wires, filaments and 
threads and also comprehends welded cloth and adherent filament or 
adherent wire cloth as well as extruded plastic mesh, such as Nylon mesh. 
As an alternative tube-defining-frame, a group of wire rings or arcuate 
wires may be secured at spaced locations along longitudinal stringers. 
While the sleeve 34 is illustrated as being closed at one end, it is also 
contemplated that the sleeve might be open at both ends and connected at 
each open end to a pair of pipe ends which are connected to a common 
source. 
Preferably the helix 32 is formed from stiff metal wire although stiff 
plastic wire has been employed with some success. The wire fabric forming 
the sleeve 34 preferably is formed from metal wires such as stainless 
steel wires. Plastic fabrics also may be employed. 
As shown in FIG. 4, an inlet pipe 40 connects to a tee 41 having two pipes 
42, two elbows 43 and two pipe ends 44, each of which receives one of the 
present distributors 45 which provide uniform dispersion across the base 
of a tank 46. 
In FIG. 5, an inlet pipe 50 has a coupling 51 connected to a pipe 52 which 
in turn is connected to a cross 53. Each of the open three arms of the 
cross 53 is connected to a pipe end 54 and in turn to a distributor 55. 
The three distributors and the perforated tube 52 supply uniform 
distribution of a fluid in a tank 56. The pipe 52 may be perforated, if 
additional fluid distribution is desired. The pipe 52 may be replaced by a 
two-ended fluid distributor. The cross 53 thus may be joined to the pipe 
50 by such two-ended fluid distributor which is similar to the 
distributors 55, except that the two-ended fluid distributor will deliver 
fluid between the pipe 50 and the cross 53. 
In FIG. 6 an inlet pipe 60 is connected through a coupling 61 to a pipe end 
62 which in turn is connected to a fluid distributor 63 which is spiraled 
about the base of a tank 64. The tube-forming-frame within the distributor 
63 retains the desired shape of the fluid distributor and provides for 
uniform distribution over the base of the tank 64. 
In FIG. 7 an inlet pipe 70 is connected to a tee 71 having pipe ends 72, 73 
serving as communicating pipe branches. A fluid distributor 74, open at 
both ends, is connected at one end to the pipe end 72 and at the other end 
to the pipe end 73. In this embodiment fluid from the inlet 70 is 
delivered through the pipe end 72, 73 directly into the closed ring-like 
distributor 74 for uniform distribution of fluid throughout the base of a 
tank 75. 
As shown in FIG. 8, the present fluid distributor can be assembled by 
wrappinig a rectangle 80 of woven wire fabric about a preformed helix 81. 
The free end of the wrapped sleeve can be secured by stitching with wire 
or threads. The open end remains available to engage the outer surface of 
a pipe end. The closed end 82 is folded and fastened with a penetrating 
fastener (not shown in FIG. 8) of the type illustrated in FIG. 3. 
Performance 
The use of the present fluid distributors has brought about a surprising 
improvement in the performance of disposable or rechargeable fluid-solids 
contacting devices. A significantly lower pressure drop for the fluid has 
been observed. Improved gas distribution has been observed within the bed 
of solids. The active life of the solids bed inventory has been increased. 
The units are easily emptied and refilled when required. There is an 
overall reduction in the treatment cost for the fluid which employs the 
present invention. 
Best Mode 
A 55-gallon steel drum was fitted with a bottom inlet pipe, two-inch 
diameter, extending through the cylindrical sidewall of the drum and an 
outlet pipe, two-inch diameter, extending through the center of the flat 
drum lid. A fluid distributor secured to the bottom inlet pipe end had a 
metal wire helix, approximately two-inches diameter, and twenty inches 
long. The helix was wrapped with 30-mesh stainless steel fabric formed 
from 0.012 inch diameter wire. The free end of the fabric was stitched 
with stainless steel wire to complete the sleeve. The open end of the 
sleeve was secured to the inlet pipe end by an encircling pipe clamp. The 
closed end of the sleeve was sealed by folding and fastening a metal rivet 
through the folds. 
The drum was filled with activated carbon particles to within 2-3 inches of 
the top. The carbon particles were screened through 4-mesh, on 10-mesh 
(U.S. Sieve). 
The resulting device was capable of treating gas flows up to about 100 
cubic feet per minute at a pressure drop of about 6.5 inches of water. 
A device, as described, was installed to treat the exhaust stream from a 
sewage sludge collector vacuum pump. The principal contaminant of the gas 
stream was hydrogen sulfide. At flow rates of about 100 cubic feet per 
minute, the device was capable of reducing the hydrogen sulfide from a 
non-acceptable level in the inlet gas to an acceptable level in the outlet 
gas for periods exceeding six months without replacement.