Патент USA US2517884

Aug., s, 195o
2,517,883
R. R. KENNEDY
APPARATUS FOR TREATMENT- OF TURBID LIQUIDS
Filed Sept. 7, 1946
2 sheets-sheet 1
vf'
INVENTOR.
@fC-_hard R, /l/e/‘fneo/y
[email protected] Q'
l
ATTORNEY
Aug. 8, 1950
2,51 7,883
R. R. KENNEDY
APPARATUS FoR TREATMENT oF TURBTD LIQuTns
Filed Sept. 7, 1946
2 Sheets-Sheet 2
ÍNVENTOR.
ß/'c?aro/ l?. Kennedy
BY
ATTORNE
2,517,883
Patented Aug. 8, _1950
UNI-TED STATES -PATEIWI‘ OFFICE.
APPARATUS Fon' TREATMENT 0F TURBID
'
l
LIQUIDs
_
.
Richardl aKen'neay, Palo Alto, Calif.
Application September 7, 1946, Serial No. 695,521
6 Claims. (c1. 21o-16)
2
This invention relates to the treatment of
turbid liquids as may be provided by water,
sewage, tradewastes, chemicals and, in` fact,
any liquid from which it is desired to remove
solids.
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'
zone, then the agitation is so vigorous that the
flocs, if formed, are broken with the result that
vthereafter the flocs are only re-formed with difii
culty into those of a settleable size. As a con
sequence, the agitators are operated at a rela
.
-tively slow or reduced speed so that inefficient
More particularly, the present invention re
coagmentation occurs andthe settleable ñocs
lates to an improved apparatus for the purifi
form piles of sludge in or adjacent to the floc
cation of liquids.V This apparatus comprises a
culation zone, Depending upon the quantity of
generally rectangular tank or trough through
which the liquid'to be purified flows from o_ne 10 the sludge and the nature `ofthe sludge, vari
ious difficulties may result from its building up
end to the other. At the inlet end of the tank
into a. pile or piles in the tank; it will be obvious
means are providedfor releasing air in the in
in the case of sewage that such a pile would be
fluent liquid to aerate the liquid, to sweep out
come septic as a result of too long retention or
of the liquid any entrained gases, to satisfy the
,
biological oxygen demand of the liquid yand to 15 stagnation.
In accordance with this invention, air agita
coagment solids in the liquid and to keep solids
tion rather than mechanical agitation is em
in a mobilized suspension by the air agitation
ployed, because of the desirable advantages of
until the solids have collected into settleable ñocs.
sweeping out of the liquids any entrained gases,
Preferably the tank or trough is so arranged
that aeration is effected only in the initial por 20 because the flocs can be coagmented as suc
cessfully with air as by mechanical means, be
tion of the tank, the remainder of the tank be
causeA any biological demand of the liquid can
ing available for sedimentation. In accord
be satisñed by the aeration, because grease, usu
ance with this invention, the sedimentation zone
ally present in sewage, is easily swept out of the
is, in fact, provided by two different regions in
the tank, one region being immediately adjacent 25 water and collected and for other presently de
tothe aeration- zone vwhile theother is provided
by the remainder of the tank; the two sedimenta
tion regions are separated by a dividingor par
tailed reasons.
'
.
By effecting ilocculation, coagmentation and
partial sedimentation on one side of the baiile
Wall, the other sedimentation region can be uti
titioning means which extends transversely 'of
the tank or trough `and’ substantially delìneates
30 lized to effect a more complete clarification of
one region from the other so that only a regu
lated liquid transfer occurs. Insofar as the in
dividually desired operating devices are con
cerned, this dividing or partitioning means can
the effluent liquid. With the liquid circulation
between the two sedimentation regions of onlyr
limited extent, the sedimentation in each region
proven satisfactory, particularly when the agi
tation is effected b'y'Émechanical means, for-the
culation-coagmentation zone.
proceeds under more or less localized conditions;
take vthe form of a baille Wall structure extend 35 in that region in intimate contact with the
aeration-ñocculation zone, coagmentation pro
ing transversely of the tank and so positioned
ceeds fairly rapidly and a large portion of the
that the liquid can .flow through the tank freely
total solids removal is effected in this region;
andfvwithout such restriction'as resultsv in the
the eii‘luent, partially clarified liquid, passing the
breaking up of the fiiocs- present in the water.4
. In prior apparatus1 ofthe same'general _type 40 baffle to the second sedimentation zone, vmoves
very slowly past the baffle, carrying a relatively
and in which a liquid is arranged to flow gener
low solid Icontent per unit of liquid volume; the
ally in a horizontal-direction through a channel
effluent liquid removed from `adjacent the upper
in which initially iiocculation vis attempted, fol
level of-y the liquid so _that >the solids are af
lowed by a later sedimentation, dependence >is
placed upon theffluid currents yestablished in the 45 forded ample opportunity to coagment and settle
in the second region without disturbance from
liquid tolcarry'the >flocs and ¿move these on> into `a
the agitation of the aerating stream in the floc
sedimentation zone.v In zpractice, this has -not
tendency existsyf'for, vthe- settleable _iiocs to vbuild
up into a pile or ypiles in those regionsof the
„
In addition to the advantages recited, 'the
50 present invention also contemplates the utiliza
tion of a rake or conveyor structure for remov
ing yall of the solids which settle to the bottom
of the tank into a sludge collection pocket'for
Obviously, if .the >agitation, is suiiiciently. vigor
eventual removal. In accordance with this in
ous to ensure that lall of the settleable flocs which
Tay form argégovedzlgvsr into‘the vS,@[email protected] 55 vention, the `settled solids are swept along the
'tankA wherein-the agitationis at a minimum.
2,517,883
4
tank bottom from the influent end of the tank
to the eii‘luent end, this type of removal of the
solids possessing the inherent advantage that
thereby the liquid and the separated, settled
air being effective to sweep out any entrained
gases, to coagment floc present in the fluid, and
to sweep out of the water grease and the like to
the tcp of the water or liquid for removal by the
skimming pipe I9. It will be noted that the air
diffusers 23 stop short of the balile wall I8 so that
flocculation and sedimentation can occur in tank
solids move in the same direction so that the
flow of liquid does not tend to break up and de
stroy the settled flocs as is the case when the
settled solids are moved countercurrent to the
portion 2l and so that baffle i3, in effect, divides
the tank into two immediately adjacent sedi
flow of liquid.
One object of the present invention is to prof 10 mentation zones.
vide an improved process and apparatus for the
In the second tank section 22, means are pro
clariñcation of turbid liquids and the removal
of solids from such liquids.
Another object of the present invention is to
provide for the continuous removal of settled 15
vided for withdrawing clarified liquid. This
means comprises the launder 26 which is sup
ported between the opposite side walls and by
solids without interference with the operation
versely of the tank and leads to an effluent oon
duit (not shown). Liquid is admitted to the
launder 23 by »a plurality of feed troughs 21 eX
tending on each side of launder 2G along the run
of the equipment or the flow of ñuid.
A further object of the present invention is to
improve the over-all eñiciency of a combined
20 of the tank and supported between trough 26
flocculation-sedimentation unit.
The invention includes other objects Aand fea->
tures of advantage, some of which, together with
thevforegoing, ’will'be' set forth in the following
description.
--
one or more columns 29 and which extends trans
’
and operator walkèways 2B.
The horizontally
extending troughs 2ï are relatively shalloìw in
depth to ensure that the liquid entering into the
effluent launder [email protected] is moving at a very slow rate
In the drawings accompanying and-forming 25 so that any solids in the liquid in a lower »por
a part hereof, I have illustrated the bestembodi
ment of invention now known to me but such
tion `oi the tank »are not disturbed.
To‘p-rovide lfor removal of settled solids, in ac-r
embodiment is to be regarded as typical only of
cordance with this invention, a movable rake or
many possible embodiments and the invention is
sludge conveyor is provided for moving the set
not limited thereto.
30 tled solids along the tank bottom. This com
In the'drawings accompanying and forming a
prises a ñrst shaft 3| provided at the inlet end
part hereoLFigure 1 is a plan view of the floc
of the tank, a second shaft 32 provided at the
culatlng sedimentation unit of the present in
other end of the tank adjacent to sludge sump
vention.
33 and -a third shaft 34 provided adjacent wall
Figure 2 is a section taken along the 'line 2-2
i5 but toward the top of the tank between shafts
of Figure 1.
»
3l and 32. Suitable sprocketsvSt are provided on
Figure 3 is a section taken along the line 3--3
each shaft on opposite sides of the tank; labout
in Figure 1.
-Figure 4 is a section taken along the line 4_4
in Figure 1.
In the drawings, and referring particularly to
Figure l, I have shown a plurality of units I l in
-a side by side relation, each unit substantially
comprising a tank or horizontal vessel 'through .
which liquid is adapted to flow from one end >of
the tank to the other. Each unit l Ál ’comprises a
bottom l2, suitable vertical side walls 13,- end
walls 14' and i5, and operator walk-ways 23 sup
ported by columns 23. An inlet pipe i6 delivers
the influent liquid to be treated to a common as
Ylaunder l 'i having a wall i 8 over which the liquid
these are trained suitable conveyor chains 31
carrying a plurality of spaced rake arms 38.
'Shaft »3d is driven by suitable means (not shown)
to `move the conveyor'cliains so that the several
rake arms 38 move'across `the bottom of the tank
slowly to sweep solids on toward the sludge sump
33 in the direction of movement of the liquid,
Sludge delivered 'to the sump 33 is moved into
a'pocket 4l by the mechanism shown particularly
in Figures 2 and 4 and which comprises a shaft 42
supported upon a column 43 and having a sprocket
44 provided adjacent each end. Shaft 42 is driven
by a suitable prime mover (not shown) rotating
shaft 4B, a chain >4l being trained about a sprocket
48 on shaft 46 and about a sprocket 129 on shaft
ñows into each unit; to ensure uniform >liquid
release into the end units, a bañle 253 is posi
tioned in the launder to ensure uniform liquid
release. Intermediate walls VHl andl i5’ is pro- >.
vided a balfle wall i6 extending transversely of
vided on Ythese and chains'54 are trained about
vthe tank and spaced from the Vbottom of the
tank to permit the fluid to circulate past the
conveyor chains 54 are `moved to carry arms 55
baffle wall ’at a low velocity. 'The upper end of
the baille wall is positioned below the elevation
of launder wall i8 so that fluids can flow over
the top-ofthe 'balile wall. Along the top of the
b'ailie ‘wall is provided a v'skimming pipe I9 so
that solids floating `on the top of the liquid in
the ‘tank can be removed.
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'152. Shaft 5| is provided at one end of sump33
and shaft 52 at the other end of the sump and
adjacent the pocket 4I. Sprockets 53 are pro
the several sprockets. Upon rotation of shaft 42,
over the bottom of the sludge'pocket 33 and to
sweep any sludge therein on into the sludge
pocket 4I from which it can be suitably removed.
In operation, with the unit I I ñlled with liquid
'to the level indicated and with air released at av
vsuitable rate through the air diffuser 23, the liq
uid is swept free of entrained gases while grease
'The baffle wall serves to >divide the tanks into
and the like is swept to the top of the liquid for
ya ñrstfsec'tio-n 2l and a second section 22. In the
removal by the skimmingrpipe 119. In addition,
any flocs present in the >liquid Aare coagmented
first section of the tank, air is released'from a
plurality “of air diff-users generally indicated by
and caused to form into larger masses which
numeral I23. 'In 'accordance-With this invention,
settle, generally between b_afñe wall I6 and the
air diffusers. The substantially clarified liquid
the -air 'diffusers ‘are positioned immediately ad
jacent to the wall 1'4 at the inlet 'end of the tank
"so that the aeration'of the liquid and any ‘circu
lation `l‘of fluid due to >the `release Uof air takes
flows over or ‘under the bañle vI3 into the larger
sedimentation zone 42 wherein’further oppor
tunity for sedimentation is afforded under nearly
'place 'in 'this portion of the tank, the release of 75 absolutely quiescent vconditions 'and’free `of the
2,517,883
5
disturbing influence oi the ilocculator-aerator.
The finally clariñed liquid is removed as it passes
over the trough 27 to issue into the launder 2B.
In this way, the liquid is treated to remove the
solids causing turbidity, all portions of the tank
being swept by the conveyor structures so that
the formation of septic masses is entirely ob
viated.
l
I claim:
l. Apparatus for the clarification of turbid
liquids having solids therein, consisting of a tank
having a bottom, two parallel side walls, land
inlet and outlet ends, a turbid liquid inlet atk the
6
which comprises an air disperser mounted below
the pool level in the inlet end, a baille disposed
across the tank at a substantial distance from the
air disperser with a substantial open space in the
tank underneath the baille to permit flow of the
liquid and with the top of the baille approximately
at the pool level, there being relatively quiescent
zones in the pool adjacent both sides of the baille,
a conveyor for scraping settled solids along the
bottom of the tank in the direction of the liquid
flow therein and underlying the zone in which
the air disperser is disposed and the two quiescent
zones, the space between the conveyor and all
-three zones being substantially unobstructed so '
inlet end, a clarified liquid outlet at an upper
that settlement of solids to the bottom can occur
portion of the outlet end, a solids outlet at a lower
inall three zones, and means for removing clari
portion of the outlet end of the tank, a baille be
ñed liquid from the pool in the quiescent zone be
tween said side walls and having its lower hori
yond the baille.
n
zontal edge spaced from the bottom of the tank
4. Apparatus according to claim 3 provided
and its upper horizontal edge adjacent the level
of the liquid outlet and spaced from the inlet end 20 with means for removing scum from the pool ad
jacent the top of the baille.
_and the outlet end to divide the tank into (a) an
` agitation and ñrst sedimentation zone and (b) .
a second sedimentation zone, means for agitat
ing liquid and solids in the tank in' a zone imme~
5. Apparatus according to claim 3 provided
with a second conveyor disposed in the tank
transversely to the first adjacent the bottom' in
diately adjacent to the inlet end and spaced from 25 the quiescent zone beyond _the second baille for
moving solids carried by the first conveyor across
the baille to provide said first sedimentation zone
the tank bottom, and a sludge .pit in the bottom
between the baille and the agitating means, con
into which the solids are moved by the second
veyor means for sweeping solids along the bot
conveyor.
torn and means for moving said conveyor means
6. Apparatus according to claim 3 in which the
to move solids on the bottom from the inlet end 30
means for removing clarified liquid from the pool
through both zones to the outlet end.
in the quiescent zone beyond the baille comprises
2. Apparatus for the clarification of turbid >
a main launder running across the tank at ap
liquids having solids therein, consisting of a tank
proximately the level of the pool, and a plurality
having a bottom, two walls, and inlet and outlet
of collection launders discharging into the main
ends, a turbid liquid inlet at -the inlet end, a 35 launder
and running lengthwise of the tank at
solids outlet at a lower portion of the outlet end
approximately
the level of the pool.
of the tank, a substantially vertical baille extend
RICHARD R. KENNEDY.
ing from wall to wall and having its lower hori
zontal edge spaced from the bottom and its upper
REFERENCES CITED ‘
horizontal edge positioned adjacent the level of 40
the liquid outlet and dividing the tank into (a)
an agitation and ñrst sedimentation zone and
The following references are of record in the
ille of this patent:
-
(b) a second sedimentation zone, means for in"
UNITED STATES PATENTS
troducing air to agitate liquid and solids in the
Number
Name
Date
45
tank in a zone immediately adjacent to the inlet
599,957
Curtis _____________ __ Mar. 1, 1898
end and spaced from the baille to provide said
1,714,739
Tark ____________ __ May 28, 1929
first sedimentation zone between the baille and
1,981,310
Currie ___________ __ Nov. 20, 1934
the agitatîng means, a conveyor having operative
2,087,851
Darby ___________ __ July 20, 1937
and return reaches both passing between the
Fischer ___________ __ Mar. 8, 1938
lower horizontal edge of the baille and the tank 50 2,110,721
2,215,185
Lund ____________ __ Sept. 17, 1940
bottom and means for moving said conveyor to
2,272,441
Streander ________ __ Feb. 10, 1942
sweep solids along the bottom from the inlet end
‘2,322,017
Hartman ________ __ June 15, 1943
through both zones to the outlet end.
2,370,974
Langdon __________ __ Mar. 6, 1945
3. In apparatus for clarifying liquid including
an elongated tank containing a pool of the liquid 55
and in which the liquid flows lengthwise from , Number
an inlet end to an outlet end, the combination
27,240
FOREIGN PATENTS
Country
Date
Great Britain ____________ __ 1905