Note: Descriptions are shown in the official language in which they were submitted.
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Apparels Brie ~LEC'~ROCHE~ICAL
PYRE I CONTAMINATED LIQUIDS
D I rye ~VE~IrTI~M
he invention relates generally to the art of liquid
purification, and more particularly to apparatus or eye-
ctrochemical purification ox r30ntaminated liquids
INDUSTRIAL PACKABLE
Roy device according to the inventiQ~ can wind up-
placation for purifying liquids contaminated by various
impurities soluble in water, suck as organic mutters-
lid Suspensors, and the like.
Roy apparatus owe toe invention may be utilized wit
the utmost advantage for purifying liquids polluted by pew
trillium products and polymer, such as industrial sewage
containing oils and polym~thyl me~hacrylates.
BACKGROUND OF TOE INVENTION
Among thy presently kiwi devices or purifying
contaminated liquids an ever increasing use have found lay
tell apparatuses or electrochemical purification of it-
rids due to their high process eschews particularly
apparatuses capable ox e~ec~i~g electrocoagulation and
electro~lotatio~ waste water treatment processes.
There are kiwi apparatuses for carrying out electron
chemical purification ox contaml~a~ed liquid in inter-
mitten or in continuous modes ox opera, the latter
appearing to be more promising.
23~
Owe such apparatus comprises a settling chamber wit
arranged Cole inside this chamber an electrocoagula-
lion chamber, a system OX consumable electrodes, pipe o'er
weeding a contaminated liquid and discharging the purified
liquid, and a means or removing Wright prom the apparatus
I US. Pat. No ~505,188; Of. 204~149~ published 1970
he Wright removing Mooney it this apparatus has the
or ox a rotating scraper arranged in the top part of the
settling chamber
This structural arrangement of' the means or remove
in froth wastes provides or part ox such wastes to be
forced by the scraper into the liquid occupying the settle
in chamber Jo be enwind by the flow of purified liquid
and thus carried away prom the apparatus, which, of course
affects the quality ox purification and consequently the
efficiency ox the apparatus
Also known is an apparatus for electrochemical treat-
mint recontaminated Lockwood (¢~/ e.g., USSR Inventor's
Certificate No 914,506; IPC C 02 7/46, published 1982)
comprising a settling chamber with pipes for discharging
the purified liquid and wastes, the settling chamber be-
in communicable with an electrocoagula~ion chamber en-
ranged Cole wherein and hazing in the bottom part
thereon a system ox consumable electrodes and a pipe for
weeding a contaminated liquid to this chamber at a toga-
lion substantially above the consumable electrodes, and
a pipe for feeding an electrolyte, eye apparatus further
comprises a mean or evacuating froth waste having a
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froth collector and a rotatable tube disposed above the
settling chamber and provided with an air injector and
a unwell at one end thereof.
he apparatus a en continuous evacuation from
the settling clamber of Roth wastes venerated during co-
adulation of contaminants by metal hydroxides in toe eye-
ctrocoagulation chamber.
However, the means or evacuating froth wastes from
the Ahab known apparatus is disadvantageous because of its
operating complete? and the need or a drive to rotate
the froth collector, which puts limitations on the effi-
Chinese of the apparatus. In addition, Jo provision is en-
visage or repeated use ox the Roth wastes or preclean-
in ox the contaminated liquid Burr it is Ted to the
apparatus.
SUGARY Ox THE I~V~TION
It it therefore a object of the present invention
to provide an apparatus for electrochemical treatment of
contaminated liquids of such a construction as to prevent
the compaction ox contaminants and sedimentation of their
fractions in the liquid being purred
Another object is to provide for the reuse ox us-
reacted metal hydroxide present it the waste to thereby
make the purification process more stable, increase the
efficiency ox the apparatus, and bring down expenditures
associated with operation of the apparatus.
These objects and other attending advantages are ox-
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twined by that ill an apparatus for electrochemical puff-
ficatio~ of co~tamiLlated liquids comprising a settling
chamber having pipes or discharging the purified liquid
and wastes disposed at the top and bottom portion err,
respectively, a froth collects all art air in Hector over-
lying this chamber, an electrocoagulation chamfer arranged
inside the settling chamber Cole therewith and sepal
rated there~xom by an anrLular partition, toe lower part
ox the electrocoagulation chamber accommodating consumable
electrodes resting substantially above a pipe for feediLlg
an electrolyte, a header connected to a line for weeding
the contaminated liquid being disposed over these elect-
nodes, according to the invention the apparatus is pro-
voided with a mixing tall communicable by a Roth duct
with the froth collector which is hermetically connected
Jo the annular partition.
This arrangement assure continuous removal prom
the settling chamber of wastes wormed during coagulation
ox contami~atiLl~ particles by electrochemically obtained
metal hydroxides taking place in the elactrocoagulation
chamber.
A a result, these wastes fail to accumulate it
the settling chamber and are removed through the Roth
duct to the mixing tank receiving continuously the con-
laminated liquid. Therewith, the wastes are utilized in
the mixing tank a a jilter bed through which the conic-
minuted liquid is caused to pass, whereas part of the us-
reacted metal hydroxides present in the wastes act to
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additionally coagulate contaminating particles of toe
liquid supplied for treatment which enables to pretreat
the contaminated liquid prior to conveying it to the eye-
ctrocoagulation chamber to improve the efficiency ox the
apparatus by up to 16%, seduce the amount ox electric
power expended or the process and slow down the rate
of dissolution ox the metal of the consumable electrodes.
Prefer Al the Roth collector is provided wit air
vets having valves, and the top part of the annular par-
tuition is disposed in said Roth collector with a clearance
relative to its inside surface defining therewith a annular
cavity, this top part of the annular partition also pie-
drably having a tapered shoulder conforming in shape to
the shape of the froth collector.
he provision ox the valved air vents in the froth
collector makes it possible to save on the energy required
for operation of the apparatus thanks to injection of we-
sues from the upper part of the settling chamber by the
atmospheric air.
he tapered guiding shoulder ox the -top of the annul-
en partition serves to reduce the likelihood of waste de-
position on the idea surface ox the Roth collector and
prevent fouling of the surface ox the no consumable elect-
nodes it the settling chamber, whereby a waving of prom
8 to 12 I in operating cysts can be attained,
Advisably, the interior ox the froth duct is pro-
voided with a insert in the Norm of an Archimedean screw
to facilitate the travel of wastes prom the settling champ
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bier to the mixing tank, the outside ox this froth duct being preferably enclosed by a steam jacket having a pipe
for weeding a mineral acid.
Toe Archimedes screw envi~5orates the process ox
separation ox froth wastes into components, such as oil,
water and air 9 and consequently enables to make these
wastes lest voluminous.
The separation ox Roth wastes inside the froth
duct proceeds most ~avourably at a temperature ox between
35 and 80C, depending on the type ox contaminants and
physical structure ox the wastes wormed during the puff-
cation process. treating the wastes thermally speeds
up such separation and enables to use the Roth duct ox
a shorter length to make the apparatus more efficient.
For correcting acidic or alkaline properties ox the
contaminated liquid prior to the electrochemical treat-
met, a mineral acid is added through the pipe mounted on
the Roy duct until a required pi value ox the liquid
it attained. this also provides a beneficial elf cat or
the coagulation process where electrochemically induced
metal hydroxides act on the disperse system,
Prey drably 9 the bottom ox toe Meg tank commune-
cater through a pipe with a recirculation live for feed-
in the contaminated Lowe to thy electrocoagulation
Camaro. It is also advisable to provide this mixing tank
in i is upper part with pipes f or f ceding the contaminated
liquid and discharging the wastes.
'the implement of the mixing tank allows a repeated
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use ox toe Roth wastes accumulating at the top of the
settling chamber and containing aggregates of co~tami-
wants coagulated with the me tat hydroxides and some us-
reacted metal hydroxides in the course ox the initial put
rakish to use the hydroxides or preliminary cogwheel-
Shea ox the contaminant. side eject ox the wastes
supplied to the Meg tank is that they are used as a
jilter bed where through the incoming contaminated Liquid
is sprayed while the reacted metal hydroxides keg-
late the impurities contained in the liquid to thus assure
precleaning ox the liquid prior to it being supplied to
the electrocoagulatio~ chamber, which results in a still
better efficiency of the apparatus and higher degree ox
purification
BRIEF DESCRIPTION I THE ACCOMPA~YI~
DRAWINGS
he invention will now be described in greater de-
jail with reverence to various pesky embodiments the-
Roy taken in conjunction with the accompanying drawings
the sole figure ox which represents a general sectional
view ox an apparatus or electroc~emical pyrrhic
ox contaminated liquids.
BEST My I CARRYING OUT THE INV~TIOW
A apparatus or electrochemical purification ox
contaminated liquids comprises disposed coccal a sell-
lint chamber 1 and an electrocoagulation chamber 2 muds
up of two detachable sectioQsO
;;L2;~Z~3
he lower section ox the electrocoagulatio~ clamber
2 project from the settling chamber 1 and accommodate
consumable electrode 3. The two section of the electron
coagulation chamber 2 are spaced prom each other to pro
vise for an annular clearance 4 there between, these two
section being interconnected by a common header 5 the
interior ox which communicate with a pipe 6 or weeding
the contaminated liquid.
Arranged between toe settling cna~ber 1 and electron
coagulation chamber 2 is an annular separating partition
7 intended to extend the -travel path of the liquid being
purified in Ike settling chamber 1. Perforate nonconsum-
able electrodes 8 are imposed below the level ox rid
substantially horizontally in a space defined by the walls
of the electrocoagulation chamber 2 and annular partition
7-
Overlying the electrocoagulation chamber 2 is Roth collector 9 defined by a tapered insert 10 Hermes
tidally connected to the annular partition 7. the Roth
collector 9 has air vents 11 with valves 12 disposed above
thy level of liquid it the settling chamber I
e upper part ox the annular partition 7 is mounted
in the Roth collector 9 with a clearance 13 relative
to its inside Ursa to Norm an annular cavity 14 con-
netted by a pipeline 15 waving a valve 16 to the pipe 17
or weeding electrolyte to the lower section of the eye-
ctrocoag~lation chamfer Z. A tapered guide shoulder I
conforming in shape to the shape of the froth collector
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_ 9
9 it provided in the upper part of the annular partition
7-
he top ox the froth collector 9 is communicated with a Meg tan 21 through a Roth duct 20~ The froth
duct 20 it arranged above the Roth collector and include
an injector 22 facing by its nozzle toward the mixing
tank 21~ as well as an insert I it the form ox an urchin
median scrod, and a pipe 24 or feeding a mineral acid.
The Roth duct 20 it enclosed on the outside by a steam
jacket 25 having pipe 26 and 27 or weeding a heat-trans-
for agent and discharging a condensate, respectively.
Disposed inside the mixing tank 21 above the toga-
lion where the Roth duct 20 is convected thereto is a
pipe 28 or supplying the contaminated liquid terminating
in a liquid spray meats 29. The interior ox the mixing
tank 21 accommodates a horizontal perorated partition
30 to separate wastes from the liquid, whereas overlying
this partition 30 is a pipe 31 or removing the wastes
from the Meg tank 21, the bottom part of the mixing
tank 21 being convected by way Of a pipe 32 and a line 33
to the pipe 6 for weeding the contaminated liquid to the
electrocoa~ulatio~ chamber 2.
The settling clamber 1 is-also provided with pipes
34 and 35 or discharge the purified Lowe and sludge,
respectively
The apparatus for electrochemical purification of
contaminated liquid operates in the following manner
Error to starting the purification process the in-
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tenor ox the electrocoagula-tion chamber 2 and settling
chamber l axe willed with an electrolyte (such as technic-
ally pure water or water containing small amounts ox awl
thereafter a voltage is applied to -toe electrodes and
or the electric current passing through electrolyte Jo.
cause anodic dissolution of the electrodes and appearance
thereon and on the nonco~sumable electrodes 8 ox gas buy-
blest
In the course ox anodic dissolution ox the electrodes
3 metal hydroxides, such as Lowe or Foe, tend to
Norm in the pure electrolyte, which hydroxides are carried
by the bubbles ox gas to the surface ox -the electrolyte
inside the Ruth collector 9 to accumulate therein and be
forced away prom the Roth layer by compressed air escape
in from the injector 22 through the Roth duct 20 to the
mixing tank 21~
Aster a while, toe supply to the apparatus ox a con-
laminated liquid through the spray 29 is initiated. When
it is necessary to correct the pi value ox the contaminate
Ed liquid, a predetermined amount ox mineral acid, such
as HC19 is added through the pipe 24.
Interaction in the mixing tank 21 ox contaminant
particles with metal hordes leads to the ~ormatiou ox
sizable aggregates of such particles tending to accumulate
above the perorated partition I to be thereafter removed
through the pipe lo this results in the growth in the
mixing tank 21 ox an additional inter Ted composed ox
coagulated aggregates the contaminated liquid partially
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cleaned ox conta~llinants in the mixing tank 21 is convey-
Ed along the line I and pipe 6 Jo thy annular clearance
4 and thereafter to the interior ox the elec-trocoagula-
lion chamber 2 immediately above the system of consume
able electrodes at a certain distance therefrom.
Contaminants which are still present in the liquid
now occupying the electrocoagulation clamber 2 interact
with particles of metal hydroxide capable ox active sorb-
lion capacity and carried by the ascending slow of the
electrolyte awry aggregates produced by coagulation are
gloated toward the surface of toe liquid in the settling
chamber l. This action is greatly facilitated by the gas
bubbles produced by the electrodes I.
oh containing aggregates ox coagulated impure-
ties and some metal hydroxides which failed to interact
are conveyed by compressed air escaping prom the injector
I prom the froth collector 9 along the froth duct 20
to the mixing tank 21~
When the Roth wastes are conveyer along the Roth
duct 20 provided with the ionizer 23 in the Norm of Arch-
median screw, they are vigorously separated into gas an
liquid containing water, contaminants 5 and metal hydra-
tides. For Easter and more e~iclent separation of wastes
it is preferable to treat the thermally by supplying a
heat transfer agent to the jacket 25 enclosing the froth
duct 20 trough the pipe 26 and discharging the condensate
through the pipe 27. 'wherewith, thermal conditions for
treating the wastes are determined by the type ox contamina-
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Zion (oil, polymers, etc.) and is maintained accordingly within a range ox prom 35 to 90C~
he purified liquid passes through the perorated
nv~corlsumable electrodes 8 and is discharged prom the
settling chamber 1 through the pipe OWE Some contaminants
are additionally carried upwards with the gas emitted
by the non consumable electrodes 8 toward the surface ox
the liquid to further enhance purification. Sludge accv.~
mutated in the Seattle chamber 1 is periodically discharge
Ed through the pipe 35.
he kowtows removal ox froth wastes prom the
froth collector 9 along the Roth dust 20 to the mixing
tank 21 enables to e~ecb precleaning ox the contaminated
liquid Ted whereinto through the spray 29, which provides
more favorable operating conditions
In vie ox the arguing, the apparatus or eye-
ctrochemical purification of contaminated liquids provides
for e~icien-t separation ox contaminants during coagulation
by metal hydroxides produced electrochemically.
Concurrently 9 the reuse ox Roth wastes containing
a certain percentage ox unrequited metal hydroxides for
precleaning the contaminated liquid enables to reduce
the amount ox impurities therein prior lo -the treatment.
this affords to still further increase the eschews of
the apparatus and reduce opera in costs.
Also, no substances are deposited on toe consumable
electrodes due to their dissolution it the pure electrolyte,
which promotes high rate of anodic dissolution ox the
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electrodes Another advantage includes substantially no-
duped deposition of froth waste on the inside surface
of the froth collector thank to their continuous removal
by the air injector producing a certain amount of under-
pressure inside the froth collector to result in a hither
degree ox purification.
urethra the use of Wastes in -the Mecca task for
the purpose ox liquid purification it greatly enhanced
by virtue of their separation into liquid and gaseous phase
en during their passage through the froth duct, the liquid
phase being utilized in the mixing tank as a filter bed
as this bed is sprayed by the contaminated liquid. In ad-
diction, the unrequited metal hydroxides act to coagulate
toe contaminating particles.
he processes may be still further invigorated by
treating the wastes thermally in the froth duct and add-
in a mineral acid to maintain an optimum pi value of
the liquid being purified.
he proposed apparatus provides a 12 to 16 % in-
crease in the efficiency ox liquid puxi~ication processes
due to precleaning, requires less electric power and disk
solvable metal of the consumable electrodes for the pro-
cuss, increases the degree of purification to between
99.3 % and 99.8%~ and requires smaller amount of metal
to be expended for this manufacture