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Patent 2825752 Summary

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(12) Patent: (11) CA 2825752
(54) English Title: FLOCCULATION MAGNETIC SEPARATOR
(54) French Title: DISPOSITIF DE SEPARATION MAGNETIQUE PAR FLOCULATION
Status: Deemed expired
Bibliographic Data
(51) International Patent Classification (IPC):
  • C02F 1/56 (2006.01)
  • B03C 1/00 (2006.01)
  • B03C 1/12 (2006.01)
  • B63B 13/00 (2006.01)
  • C02F 1/52 (2006.01)
(72) Inventors :
  • TERUI, SHIGEKI (Japan)
  • YAMADA, MANABU (Japan)
(73) Owners :
  • HITACHI, LTD. (Japan)
(71) Applicants :
  • HITACHI, LTD. (Japan)
(74) Agent: NA
(74) Associate agent: NA
(45) Issued: 2016-01-12
(86) PCT Filing Date: 2012-01-26
(87) Open to Public Inspection: 2012-08-02
Examination requested: 2013-07-24
Availability of licence: N/A
(25) Language of filing: English

Patent Cooperation Treaty (PCT): Yes
(86) PCT Filing Number: PCT/JP2012/051612
(87) International Publication Number: WO2012/102324
(85) National Entry: 2013-07-24

(30) Application Priority Data:
Application No. Country/Territory Date
2011-015362 Japan 2011-01-27

Abstracts

English Abstract



Provided is a flocculation magnetic separator which reduces
the used amounts of magnetic powder as well as the collected flocs
thus recovered, without using a chemical such as hydrochloric acid.
The flocculation magnetic separator comprises a return and
addition unit (18) which returns the collected flocs discharged
from a magnetic separation unit (16) to a raw water supply pipe
(12) at an upstream position of a rapid stirring tank (26) and
at an upstream position where a flocculant is added. This process
for returning the collected flocs to the raw water supply pipe
(12) enables the collected flocs to be recycled without using a
chemical such as hydrochloric acid. Further, this process also
enables the magnetic powder contained in the collected flocs to
be recycled, resulting in the reduction of the used amounts of
brand-new magnetic powder.


French Abstract

La présente invention concerne un dispositif de séparation magnétique par floculation qui est apte à réduire le floc récupéré et la quantité de poudre magnétique utilisée sans recourir à aucun produit chimique, tel que l'acide chlorhydrique. Ledit dispositif de séparation magnétique par floculation possède un dispositif d'addition et de renvoi (18), qui renvoie le floc récupéré - évacué depuis un dispositif de séparation magnétique (16) - dans un tube d'alimentation en eau non traitée (12), à une position en amont d'un réservoir à agitation rapide (26) avant l'ajout d'un floculant. Grâce au renvoi du floc récupéré dans le tube d'alimentation en eau non traitée (12), il est possible de réutiliser le floc récupéré sans recourir à un produit chimique tel que l'acide chlorhydrique. En outre, il est possible de réutiliser la poudre magnétique contenue dans le floc récupéré, et de réduire la quantité de nouvelle poudre magnétique utilisée.

Claims

Note: Claims are shown in the official language in which they were submitted.



41

CLAIMS

1. A flocculation magnetic separator comprising:
a first stirring tank connected with a raw water supply pipe
which supplies raw water, for stirring at a first stirring rate
the raw water added with a flocculant and magnetic powder which
is supplied from a magnetic powder supply device, thereby to form
magnetic microflocs containing the magnetic powder;
a second stirring tank for stirring, at a second stirring
rate slower than the first stirring rate, treated water to which
a polymer flocculant is added, thereby flocculating the magnetic
microflocs, the treated water containing the magnetic microflocs
and being discharged from the first stirring tank;
a magnetic separation device for separating the flocculated
magnetic microflocs by a magnetic filter from the treated water
discharged from the second stirring tank to collect the
flocculated magnetic microflocs on the magnetic filter, and
scraping the collected flocculated magnetic microflocs off the
magnetic filter by a scraper;
a collected floc receiver tank storing the flocculated
magnetic microflocs scraped by the scraper; and
a return and addition device for recycling magnetic powder
contained in the flocculated magnetic microflocs by returning by
a pump the flocculated magnetic microflocs stored in the
collected floc receiver tank to the raw water supply pipe


42

upstream of the first stirring tank and at a first position
upstream of where the flocculant is added, thereby to add the
collected microflocs to the raw water.
2. The flocculation magnetic separator as described in claim 1,
further comprising:
a concentration detection device detecting suspended solids
concentration in the raw water, at a second position upstream of
where the magnetic powder, the flocculant and the collected
microflocs are added; and
a control device controlling return amounts of the collected
microflocs conducted by the return and addition device, and
addition amounts of the magnetic powder conducted by the magnetic
powder supply device, based on both the suspended solids
concentration detected by the concentration detection device and
maximum suspended solids concentration in raw water set in
advance.
3. The flocculation magnetic separator as described in claim 2,
wherein the control device stops a process of returning the
collected microflocs conducted by the return and addition device,
when the suspended solids concentration detected by the
concentration detection device is equal to the maximum suspended
solids concentration in raw water, and simultaneously the control

43
device controls addition amounts of the magnetic powder conducted
by the magnetic powder supply device; and
the control device increases return amounts of the collected
microflocs conducted by the return and addition device, as the
suspended solids concentration becomes lower than the maximum
suspended solids concentration in raw water, and simultaneously
the control unit decreases addition amounts of the magnetic
powder conducted by the magnetic powder supply device.
4. The flocculation magnetic separator as described in claim 1,
further comprising:
a magnetic powder extraction device which is arranged at a
return pipeline located between the return and addition device
and the raw water supply pipe;
the magnetic powder extraction device comprising:
a crush device crushing the collected microflocs by shearing
force;
an extraction device selectively extracting only a magnetic
powder component from the collected microflocs thus crushed by
using magnetic force; and
a return device returning the magnetic powder component thus
extracted to the raw water supply pipe.
5. The flocculation magnetic separator as described in claim 1,
further comprising a sterilization device sterilizing plankton

44/
and bacteria contained in the collected microflocs, arranged in a
return pipeline of the collected microflocs conducted by the
return and addition device.

Description

Note: Descriptions are shown in the official language in which they were submitted.


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FLOCCULATION MAGNETIC SEPARATOR
BACKGROUND OF THE INVENTIION
FIELD OF THE INVENTION
[0001]
The present invention relates to a flocculation magnetic
separator of flocculating plankton and bacteria contained in
ballast water and separating the flocs thus collected by magnetic
force.
DESCRIPTION OF THE RELATED ART
[0002]
According to the International Convention for the Control
and Management of Ship's Ballast Water adopted by the
International Maritime Organization (IMO) in 2004, the ships are
demanded to be equipped with a system of removing or sterilizing
plankton and bacteria contained in ballast water. This
convention was adopted aiming to prevent microorganisms from
moving through ballast water (or sea water), the ecosystem from
being destructed via the diffusion of the microorganisms, and a
health hazard from being caused by the microorganisms.
At present, technologies for treating ballast water are
actively developed by combining a variety of water treatment
technologies, including a chemical treatment using sodium
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hypochlorite or the like, an ozonation, ultra-violet irradiation,
heat treatment, and magnetic separation or the like.
[0003]
Here, a flocculation magnetic separator disclosed in Patent
Document 1 is operated by the steps of: adding magnetic powder
and a flocculant to ballast water (or raw water); stirring the
resulting mixture to form magnetic flocs containing
microorganisms and bacteria mixed in the ballast water;
separating the magnetic flocs from the ballast water by a magnetic
separation device; and collecting relatively large solid
materials unable to be flocculated by themselves (for example,
small fishes each with a several millimeters size, and seaweeds)
by a dram type filter.
When the flocculation magnetic separator is operated, the
used flocculant is highly safety agent that is also used for the
treatment of tap water. Further, such a water treatment using
a flocculant is less risky than a treatment using chemicals such
as chlorine. In other words, the flocculation treatment has less
liability to secondarily contaminate the environment by the
chemicals remained in the ballast water at the discharging time
and related by-products.
Moreover, the flocculation magnetic separator flocculates
not only microorganisms and bacteria but also sand and sludge
included in the ballast water, thereby to simultaneously separate
and remove all the materials. This allows the flocculation
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magnetic separator to have a secondary effect of preventing the
sand and sludge from being accumulated on a bottom of a ballast
tank.
[0004]
However, there are the following issues arising in the
flocculation magnetic separator disclosed in Patent Document 1.
One issue is that the used amounts of the expensive magnetic powder
should be reduced, with keeping the cleaning performance of
ballast water. The other issue is that the total amounts of the
collected flocs should be reduced.
[0005]
Namely, with respect to a flocculation magnetic separator,
magnetic powder thus added should become uniformly contained in
all the flocs as much as possible, when the magnetic flocs are
formed. Hereby, should be used the magnetic powder composed of
the particles each having an extremely small particle size in
several microns as well as an equal particle size.
[0006]
However, it should be noted that such magnetic powder is
very expensive, resulting in the increase in the running costs
of a flocculation magnetic separator. Therefore, it is demanded
to reduce the used amounts of magnetic powder as much as possible.
Further, assuming a flocculation magnetic separator is installed
in a ship, reduced amounts of the magnetic powder allows a storage
tank of the magnetic powder to be downsized.
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This advantage provides a great merit with the installation
of the flocculation magnetic separator into the inside of the ship
having a limited space for arranging various devices.
Simultaneously, this advantage allows a frequency of the
operations for supplying the magnetic powder into the inside of
the ship to be reduced, resulting in the reduction of the burden
of sailors.
[0007]
In the meantime, the collected flocs discharged from the
magnetic separator have to be stored in a tank and treated as an
industrial waste. Thus, it is strongly demanded that the
collected flocs should be recycled as much as possible to reduce
the total amounts thereof, thereby to downsize a storage tank
thereof, achieve space saving, and reduce the costs of treating
industrial wastes.
[0008]
From the viewpoints as mentioned above, it is noted that
Patent Document 2 discloses a magnetic separation cleaner having
the following feature. That is, the magnetic separation cleaner
is operated in the steps of: adding hydrochloric acid to collected
flocs with stirring the mixture; decomposing a polymer flocculant
thereby to be separated into a decomposed flocculant which
contains an oil and treated water, and a magnetic powder
component; and returning the decomposed flocculant and magnetic
powder into raw water so as to recycle those materials.
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PRIOR ART DOCUMENTS
PATENT DOCUMENTS
[0009]
Patent Document 1: JP H09-117618
Patent Document 2: JP 2006-718
DISCLOSURE OF INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0010]
In Patent Document 2, hydrochloric acid is used for
recycling magnetic powder. Herein, it should be noted that the
use of hydrochloric acid in a ship needs to file proof documents
with the IMO; the documents demonstrating the safety of installing
a treatment system using hydrochloric acid, that is, a strong acid.
Further, needed are additional proof documents to be filed with
the IMO; the documents demonstrating the reliability in the
process of neutralizing treated materials.
Accordingly, such extremely complicated procedures are
required to use such a treatment system in which hydrochloric acid
is used.
[0011]
From the circumstance as described hereinbefore, it has
been demanded to develop a flocculation magnetic separator which
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is capable of reducing the amounts of the collected flocs as well
as the used amounts of the magnetic powder; the flocculation
magnetic separator being capable of physically removing
microorganisms and bacteria included in ballast water as
described in Patent Document 1.
[0012]
Here, a problem caused by a process of reducing the used
amounts of the magnetic powder and the amounts of the collected
flocs without using a chemical such as hydrochloric acid for
treating raw water, is not limited to only the treatment case of
ballast water. The same problem is raised in the case of raw
water which is treated onshore.
[0013]
The present invention has been developed in the light of the
problems as described above. Therefore, an object of the present
invention is to provide a flocculation magnetic separator capable
of reducing the used amounts of magnetic powder without using a
chemical such as hydrochloric acid, as well as the amounts of the
collected flocs, so as to treat raw water.
MEANS FOR SOLVING THE PROBLEMS
[0014]
Accordingly, the present invention has been made in order to
achieve the above mentioned object. In accordance with an aspect
there is provided a flocculation magnetic separator comprising:
a first stirring tank connected with a raw water supply pipe
which supplies raw water, for stirring at a first stirring rate
the raw water added with a flocculant and magnetic powder which

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6a/45
is supplied from a magnetic powder supply device, thereby to form
magnetic microflocs containing the magnetic powder;
a second stirring tank for stirring, at a second stirring
rate slower than the first stirring rate, treated water to which
a polymer flocculant is added, thereby flocculating the magnetic
microflocs, the treated water containing the magnetic microflocs
and being discharged from the first stirring tank;
a magnetic separation device for separating the flocculated
magnetic microflocs by a magnetic filter from the treated water
discharged from the second stirring tank to collect the
flocculated magnetic microflocs on the magnetic filter, and
scraping the collected flocculated magnetic microflocs off the
magnetic filter by a scraper;
a collected floc receiver tank storing the flocculated
magnetic microflocs scraped by the scraper; and
a return and addition device for recycling magnetic powder
contained in the flocculated magnetic microflocs by returning by
a pump the flocculated magnetic microflocs stored in the
collected floc receiver tank to the raw water supply pipe
upstream of the first stirring tank and at a first position
upstream of where the flocculant is added, thereby to add the
collected microflocs to the raw water.
That is, provided is a flocculation magnetic separator
including: a first stirring tank _________________________________

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of forming magnetic microflocs containing magnetic powder; and
a second stirring tank of enlarging the magnetic microflocs via
stirring the water to be treated to which a polymer flocculant
has been added.
Herein, the first stirring tank is connected with a raw water
supply pipe of supplying raw water, and the magnetic microflocs
are formed by rapidly stirring the raw water to which magnetic
powder and a flocculant have been added. Such magnetic powder
is supplied from a magnetic powder supply device. Further, the
raw water to be treated in the second stirring tank contains the
magnetic microflocs discharged from the first stirring tank. The
second tank is stirred at a lower rotational rate than the first
tank.
Further, the flocculation magnetic separator including: a
magnetic separation device of collecting the enlarged flocks by
magnetic force; and a return and addition device of returning the
flocs thus collected by the magnetic separation device to the raw
water supply pipe located at an upstream position of the first
stirring tank and at an upstream position where the flocculant
is added to the raw water. Then, the return and addition device
adds the collected flocs to the raw water.
[0015]
Here, the flocculation magnetic separator of the present
invention includes the return and addition device of returning
the flocs discharged from the magnetic separation device to the
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raw water supply pipe at the upstream position of the first
stirring tank and at the upstream position where the flocculant
is added. The collected flocs discharged from the magnetic
separation device are once stored in a collected floc receiver
tank. Then, the collected flocs are returned to the raw water
supply pipe by the return and addition device.
Accordingly, the magnetic powder contained in the collected
flocs is recycled in the present invention. This recycling
process allows the used amounts of the magnetic powder to be
reduced without using a chemical such as hydrochloric acid or the
like, and further the amounts of the collected flocs to be reduced.
Moreover, this recycling process allows a complicated separation
and extraction treatment of the magnetic powder to be unnecessary.
Note the collected flocs which are not returned are allowed to
overflow from the collected floc receiver tank as excess of the
collected flocs, thereby to be separately stored in a collected
floc storage tank.
[0016]
The flocculation magnetic separator of the present
invention preferably includes a concentration detection device
of detecting concentration of suspended solids in the raw water
at the upstream position where the magnetic powder, the flocculant
and the collected flocs are added.
Further, the flocculation magnetic separator preferably
includes a control device of controlling the return amounts of
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the collected flocs conducted by the return and addition device
together with the addition amounts of the magnetic powder
conducted by the magnetic powder supply device.
Herein, the control device performs the above described
operation based on both the concentration of suspended solids
detected by the concentration detection device and the maximum
suspended solids concentration in raw water set in advance.
[0017]
The control device of the present invention controls the
return amounts of the collected flocs conducted by the return and
addition device and the addition amounts of the magnetic powder
conducted by the magnetic supply device.
Herein, the control unit performs the operation based on
both the concentration of suspended solids detected by the
concentration detection device and the maximum suspended solids
concentration in raw water set in advance (or designed value of
the flocculation magnetic separator).
According to the present invention, the concentration of
suspended solids in raw water is detected, and subsequently it
is confirmed that the detected concentration is lower than the
maximum suspended solids concentration in raw water. This
procedure allows a complicated separation and extraction
treatment to be unnecessary, and therefore the collected flocs
to be recycled by a simple and low cost system structure.
Moreover, the recycling process of the magnetic powder contained
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in the collected flocs enables the used amounts of brand-new
magnetic powder to be reduced. Hereby, this also allows the
generated amounts of the collected flocs derived from the
brand-new magnetic powder to be further reduced.
[0018]
Further, according to the present invention, if the
concentration of suspended solids detected by the concentration
detection device is determined to be equal to the maximum
suspended solids concentration in raw water, preferably the
control device stops the returning process of the collected flocs
conducted by the return and addition device. Simultaneously,
preferably the control device controls the addition amounts of
the magnetic powder conducted by the magnetic powder supply device,
thereby to increase the returning amounts of the collected flocs
conducted by the return and addition device, as the concentration
of suspended solids becomes lower than the maximum suspended
solids concentration in raw water. Further, preferably the
control device controls the addition amounts of the magnetic
powder conducted by the magnetic powder supply device such that
the addition amounts thereof are to be decreased.
Accordingly, the above mentioned procedure of the present
invention enables treatment performance of the flocculation
magnetic separator to be more stabilized, regardless of the
concentration of suspended solids in the raw water.
[0019]
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In the meantime, according to the present invention, if the
concentration of suspended solids in the raw water becomes higher
than the maximum suspended solids concentration in raw water, the
collected flocs cannot be returned to the raw water supply pipe.
However, in order to return the collected flocs so as to recycle
the magnetic powder included in the collected flocs even in the
above mentioned case, the returning process needs to extract only
the magnetic powder component from the collected flocs and remove
other suspended solid components.
[0020]
From the viewpoints as described hereinbefore, in the
present invention, a magnetic powder extraction device is
provided with a return pipeline located between the return and
addition device and the raw water supply pipe.
The magnetic
powder extraction device includes: a crush device of crushing the
collected flocs by shearing force; an extraction device of
selectively extracting only the magnetic powder from the
collected flocs thus crushed by magnetic force; and a return
device of returning the extracted magnetic powder to the raw
water supply pipe.
[0021]
The magnetic powder extraction device of the present
invention conducts the steps of: extracting the magnetic powder
component from the collected flocs; and removing other suspended
solid components, through the steps in two stages as mentioned

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below.
[0022]
In the steps of the first stage, the collected flocs are
crushed by applying physical force thereto. Note the collected
flocs are formed by tight flocculation of magnetic powder and
other suspended solid components via the aid of an inorganic
flocculant and a polymer flocculant. Therefore, the crushing
step of the tight flocculation is conducted by a supersonic wave
crusher, a line mill or a ball mill in order to crush the tight
flocculation.
That is, the collected flocs are crushed by only physical
force without using a chemical such as hydrochloric acid. This
allows risk in the step caused by leakage of a chemical to be lower,
providing a highly safety feature with the step. As a result,
when the magnetic powder extraction unit is installed in a ship,
this safety feature facilitates the approval proceedings of the
installation by the IMO to be conducted more simply.
[0023]
Next, in the steps of the second stage, the crushed flocs
comprised of magnetic powder are extracted from the original
collected flocs by an extraction device using magnetic force.
Other suspended solid components are thus removed from the
extracted flocs. Then, the extracted collected flocs are
returned to the raw water supply pipe by a return device.
Note the suspended solid components other than magnetic
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powder have been removed from the collected flocs which are to
be returned. Hereby, the collected flocs comprised of magnetic
powder which are to be returned are highly pure. Accordingly,
the collected flocs can be returned to the raw water supply pipe,
even though the suspended solids concentration in raw water is
high.
[0024]
In the present invention, it is preferable to arrange a
sterilization device of sterilizing plankton and bacteria
contained in the collected flocs, in a return passage of the
collected flocs. Herein, the returning process is conducted by
the return and addition device.
[0025]
When the flocculation magnetic separator of the present
invention is applied to a ballast water treating system installed
in a ship, plankton and bacteria contained in the collected flocs
are sterilized by a sterilization device. Then, the collected
flocs thus sterilized are returned to a raw water supply pipe.
This procedure can suppress another burden, loaded on the raw
water by the collected flocs.
EFFECT OF THE INVENTION
[0026]
The flocculation magnetic separator of the present
invention enables the used amounts of magnetic powder to be
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reduced without using a chemical such as hydrochloric acid, and
further the used amounts of the collected flocs to be reduced.
BRIEF DESCRIPTION OF DRAWINGS
[0027]
FIG.1 is a diagram showing a whole construction of a
flocculation magnetic separator in an embodiment.
FIG. 2 is a schematic block diagram showing a base body of
the flocculation magnetic separator including no magnetic powder
extraction unit. Note FIG. 1 shows the separator equipped with
the magnetic powder extraction unit.
FIG. 3 is a schematic block diagram of the flocculation
magnetic separator in FIG. 1.
FIG. 41s a graphic diagram showing return rates of collected
flocs in the flocculation magnetic separator in FIG. 2.
FIG. 5 is a graphic diagram showing return rates of collected
flocs in the flocculation magnetic separator in FIG. 3.
FIG. 6 is a graphic diagram showing a relationship between
concentration of added magnetic powder and a removal rate of
flocs.
FIG. 7 is a graphic diagram showing a relationship between
SS (suspended solids) concentration in raw water and a return rate
of flocs.
EMBODIMENTS FOR CARRING OUT THE INVENTION
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[0028]
Hereinafter, preferable embodiments of the flocculation
magnetic separator in the present invention will be explained in
detail referring to the attached drawings.
[0029]
FIG. 1 is a diagram showing a whole construction of the
flocculation magnetic separator 10 in an embodiment. The
flocculation magnetic separator 10 includes: a raw water supply
pipe 12; a flocculation unit 14; a magnetic separation unit (or
magnetic separation device) 16; a return and addition unit (or
returning and adding device) 18; a magnetic powder extraction unit
(or magnetic powder extraction device) 20; a heat sterilization
unit (or sterilization device) 22; and a control unit (or control
device) 24.
[0030]
Note the flocculation magnetic separator 10 in the present
embodiment is applied to a ballast water treating system installed
in a ship. Hereby, the separator 10 is equipped with a heat
sterilization unit 22. However, when such a flocculation
magnetic separator is arranged on shore, the heat sterilization
unit 22 is not an essential component of the separator 10.
Further, if the flocs collected by the magnetic separation
unit 16 are directly returned to the raw water supply pipe 12
through the return and addition unit 18, the magnetic powder
extraction unit 20 also is not an essential component of the
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separator 10.
[0031]
The flocculation unit 14 includes a high speed stirring tank
(or first stirring tank) 26 and a low speed stirring tank (or
second stirring tank) 28. The
flocculation unit 14 produces
magnetic microflocs from water to be treated (or sea water) which
has been supplied through the raw water supply pipe 12. For this
operation, the raw water supply pipe 12 is equipped with a
magnetic powder supply unit (or magnetic powder supplier) 30 and
a flocculant addition unit 32.
Further, a polymer flocculant
addition unit 36 is arranged at a pipeline 34 through which the
water to be treated is supplied from the high speed stirring tank
26 to the low speed stirring tank 28.
[0032]
The magnetic powder supply unit 30 has a magnetic powder
injection pump 38.
A rotational rate of the magnetic powder
injection pump 38 is controlled by the control unit 24.
This
mechanism controls the addition amounts of brand-new magnetic
powder added to the raw water supply pipe 12.
[0033]
Further, an SS (Suspended Solids: hereinafter referred to as
SS) concentration meter 40 (or turbidimeter) which detects
concentration of suspended solids is attached to an upstream
position of the raw water supply pipe 12. The SS concentration
data detected by the SS concentration meter 40 are outputted to

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the control unit 24. Then, based on the SS concentration data,
the control unit 24 controls a rotational rate of the magnetic
powder injection pump 38 as well as a rotational rate of a collected
floc return pump 42 which is a component of the return and addition
unit 18.
Based on the above mentioned mechanism, brand-new magnetic
powder and collected flocs are added to raw water which flows
through the raw water supply pipe 12. Herein, note the attachment
position of the SS concentration meter 40 is not limited to the
raw water supply pipe 12. In this regard, any attachment position
may be preferable as long as the attachment position is located
at the upstream region to which the magnetic powder, the
flocculant and the collected flocs are added.
For example, the
SS concentration meter 40 may be attached to a tank of temporarily
storing the raw water.
[0034]
Here, as magnetic powder, triion tetraoxide powder may be
preferably used. As a flocculant, a water soluble inorganic
flocculant such as poly aluminum chloride, iron (III) chloride,
and iron (III) sulfate may be preferably used. Further, as a
polymer flocculant, an anionic flocculant and a non-ionic
flocculant may be preferably used.
[0035]
The high speed stirring tank 26 has a stirring blade (not
shown in FIG. 1) which rapidly rotates so as to stir a mixture
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of raw water, magnetic powder, a flocculant and the collected
flocs which have been added to the raw water. The raw water to
which magnetic powder, a flocculant and the collected flocs have
been added is rapidly stirred by the stirring blade. This
operation allows extremely small magnetic microflocs each having
a several tens m size to be formed in the high speed stirring
tank 26. When the magnetic microflocs are formed, microorganisms
and bacteria in the raw water are adsorbed on the magnetic powder
which works as an adsorption core since the microorganisms and
bacteria are electrically charged, thereby to be taken in the
magnetic microflocs.
[0036]
The low speed stirring tank 28 is constructed as a multistage
stirring tank comprised of a series of multiple tanks. A stirring
tank at each stage is equipped with a stirring blade (not shown
in FIG. 1). As to the stirring tank 28 constructed in a multistage
form, a stirring speed at each tank is set so that the stirring
speed is stepwise decreased from an upstream stirring tank to a
downstream stirring tank. Hereby, water to be treated of
containing the magnetic microflocs and the polymer flocculant
which has been added to the water to be treated are supplied to
the slow speed stirring tank 28 from the high speed stirring tank
26. As a result, the stirring speed is stepwise lowered along
with from the upstream stirring tank to the downstream tank.
This mechanism facilitates the magnetic microflocs to be
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grown up, thereby to become enlarged flocs. Further, since the
stirring speed at each tank is stepwise lowered, there is little
chance that the enlarged flocs are broken by the respective
stirring blades.
[0037]
The magnetic separation unit 16 collects the enlarged flocs
from the water to be treated, comprising: a magnetic separation
tank 44, a magnetic filter 46, a scraper (not shown in FIG. 1)
and a conveyer system 48. Water to be treated containing
enlarged flocs is supplied from the low speed stirring tank 28
to the magnetic separation tank 44. The magnetic filter 46 has,
for example, a shape of a rotational drum, and at least a part
of the filter 46 is immersed in the water to be treated in the
magnetic separation tank 44. Hereby, the magnetic separation
filter 46 collects enlarged flocs which drift in the magnetic
separation tank 44 filled with the water to be treated.
Then, the enlarged flocs thus collected (or collected
flocs) are lifted up from the magnetic separation tank 44
associated with the rotational movement of the magnetic filter
46. The lifted enlarged flocs are scraped from the magnetic
filter 46 by the scraper. After that, the collected flocs thus
scraped are conveyed to a collected floc receiver tank 50 by the
conveyer system 48 such as a screw conveyer. The collected flocs
thus conveyed are temporarily stored in the tank 50.
[0038]
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The collected flocs stored in the collected floc receiver
tank 50 are sent to a heat sterilization unit 22 by a collected
floc return pump 42. The heat sterilization unit 22 sterilizes
microorganisms and bacteria contained inside the collected flocs
by the heat treatment of the collected flocs.
Note the collected flocs are in a slurry form. Therefore,
it is preferable to use a positive displacement pump such as a
tube pump or a single axis screw type pump, as a collected floc
return pump 42. A heating temperature for sterilizing bacteria
or the like is set in the range from 75 to 80 C, and a heating
time is set in about three minutes.
[0039]
In the meantime, the magnetic powder extraction unit 20
includes: crush units (or crush devices) 52 and 54 of crushing
the collected flocs by shearing force; an extraction unit (or
extraction device) 56 of selectively extracting a magnetic powder
component from the crushed collected flocs by magnetic force; and
a pump (or return device) 58 of returning the extracted magnetic
powder component to the raw water supply pipe 12.
[0040]
As mentioned hereinbefore, the flocculation magnetic
separator 10 shown in FIG. 1 represents an embodiment in which
the heat sterilization unit 22 is arranged at the upstream
position of the collected floc return passage which is included
in the return and addition unit 18. Further, in the embodiment,
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the magnetic powder extraction unit 20 is arranged at the
downstream position of the return passage.
[0041]
A crush unit 52 is a line mill which generates strong
shearing force by rapidly rotating the stirring blade 60 having
a special shape. In contrast, another crush unit 54 is a
supersonic wave crusher (frequency= about 20 kHz) which generates
shearing force with a liquid 64 by immersing a rod shaped vibrator
62 vibrating at the frequency of the supersonic wave, in the liquid
64.
Note in the present embodiment, two crush units 52 and 54
are arranged, while either of the units may be arranged.
Alternatively, a ball mill 65 may be used as a crush unit (or crush
device).
[0042]
Then, the collected flocs crushed by the crush units 52 and
54 are supplied to an extraction unit 56. The extraction unit
56 extracts a magnetic powder component from the crushed collected
flocs by magnetic force. To such an extraction unit 56, applied
is a system using a magnetic disk or a magnetic drum, permanent
magnets being embedded in the disk and the drum.
This construction enables the magnetic powder component to
be extracted from the collected flocs, and SS substances other
than the magnetic powder component to be discharged.
[0043]
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Here, a discharged content of the SS substances other than
the magnetic powder component is about 0.2% of the throughput of
the flocculant magnetic separator 10. Accordingly, the
extraction unit 56 in the present embodiment may be smaller than
the magnetic separation unit 16 which is a main component.
The collected flocs, of which extraction treatment for
extracting the magnetic powder component has been finished, are
stored in a collected floc storage tank (not shown in FIG. 1) as .
separated and collected flocs. This process is similar to the
process conducted for an excess of the collected flocs which are
generated in the collected floc receiver tank 50. Note the
magnetic powder component extracted by magnetic force has a low
water content, resulting in a low flowability. Hereby, the
magnetic powder component is supplied to a tank 68 of storing clear
water 66, thereby to be diluted therein. After that, the magnetic
powder component thus diluted with clear water 66 is returned to
the raw water supply pipe 12 by a pump 58. This process enables
magnetic powder in a high purity to be added to the water to be
treated which flows through the raw water supply pipe 12.
Herein, in the raw water supply pipe 12, a return position
of the collected flocs and an addition position of the magnetic
powder are located at a downstream region of the SS concentration
meter 40, at an upstream region of the high speed stirring tank
26, and at an upstream region of the place where a flocculant is
added. Note the rotational rate of the pump 58 is controlled by
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the control unit 24 based on the SS concentration date measured
by the SS concentration meter 40.
[0044]
Next, the effects of the flocculation magnetic separator
10 constructed as mentioned hereinbefore will be explained in
detail.
[0045]
FIG. 2 is a schematic block diagram showing a base body of
a flocculation magnetic separator 10. This base body of a
flocculation magnetic separator 10 represents a separator
constructed by removing the magnetic powder extraction unit 20
from the flocculation magnetic separator 10 shown in FIG. 1.
That is, the flocculation magnetic separator 10 in FIG. 2
represents an embodiment in which only the heat sterilization unit
22 is arranged in the return passage of the collected flocs.
Herein, the return process is conducted by the return and addition
unit 18.
[0046]
In the flocculation magnetic separator 10 in FIG. 2,
arranged is the return and addition unit 18 which returns and
adds the collected flocs discharged from the magnetic separation
unit 16 to an upstream region of the position where a flocculant
is added, in the raw water supply pipe 12. The collected flocs
discharged from the magnetic separation unit 16 are temporally
stored in a collected floc receiver tank 50 (see FIG. 1). Then,
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the resulting collected flocs are returned to the raw water supply
pipe 12 by a collected floc return pump 42 included in the return
and addition unit 18.
In contrast, the non-returned collected flocs are
separately stored in a collected flock storage tank (not shown
in FIG. 2) by overflowing the flocs from the collected floc
receiver tank 50 as an excess of the flocs.
[0047]
As mentioned above, the returning procedure of the
collected flocs to the raw water supply pipe 12 allows the
collected flocs to be recycled without using a chemical such as
hydrochloric acid. As a result, the magnetic powder component
contained in the collected flocs, allowing the used amounts of
brand-new magnetic powder to be reduced. Further, this also
allows the total amounts of the collected flocs thus generated
due to the addition of the brand-new magnetic powder to be reduced.
[0048]
Meanwhile, the control unit 24 controls return amounts of
collected flocks conducted by the return and addition unit 18 and
addition amounts of brand¨new magnetic powder conducted by the
magnetic powder supply unit 30. Herein, this controlling
operation is conducted based on the SS concentration detected by
the SS concentration meter 40 and the maximum SS concentration
in raw water, the maximum SS concentration in raw water having
been set in advance.
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[0049]
That is, when the SS concentration detected by the SS
concentration meter 40 is equal to the maximum SS concentration
in raw water, the control unit 24 stops the returning operation
of the collected flocs conducted by the return and addition unit
18. Simultaneously, the control unit 24 controls the addition
amounts of brand-new magnetic powder conducted by the magnetic
powder supply unit 30.
At that time, as the SS concentration becomes lower than
the maximum SS concentration in raw water, the control unit 24
increases the return amounts of the collected flocs conducted by
the return and addition unit 18. Simultaneously, the control unit
24 reduces the addition amounts of brand-new magnetic powder
conducted by the magnetic powder supply unit 30.
[0050]
The above mentioned procedure allows the treatment
performance of the flocculation magnetic separator 10 in FIG. 2
to be stabilized without being influenced by the SS concentration
in raw water. Note a unit with the reference numeral 70 represents
a filter. The filter 70 separates treated water and washing water
from the water to be treated which has been separated by the
magnetic separation unit 16. Then, the washing water is returned
to the raw water supply pipe 12 through the pipeline 72.
[0051]
Next, more specifically, a control method conducted by the
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control unit 24 will be explained in detail.
[0052]
First, note the return amounts of the collected flocs are
controlled by the rotational rate of the collected floc return
pump 40, which is controlled by the control unit 24. Herein, the
rate in the return amounts of the collected flocs are adjusted
in the range from 0 to 100% of the total discharged amounts of
the collected flocs.
[0053]
Secondly, note the return amounts of the collected flocs
are controlled by the control unit 24 based on the SS concentration
in raw water detected by the SS concentration meter 40 together
with the maximum SS concentration in raw water set in advance.
[0054]
For example, it is premised that the flocculation magnetic
separator 10 is designed to have the maximum SS concentration in
raw water of 50 mg/L. In that case, it is assumed that the raw
water having the SS concentration of 50 mg/L flows into the raw
water supply pipe 12. If 100% of the collected flocs return to
the raw water, this means that the SS in the amounts corresponding
to the SS concentration of 50 mg/L is returned to the raw water.
Accordingly, the SS concentration in the raw water flowing into
the high speed stirring tank 26 is represented by the following
formula: 50 + 50 - 100 mg/L. Hereby, the SS concentration in the
raw water having a value of 100 mg/L is higher than the maximum
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SS concentration in raw water which represents the marginal
ability performed by the flocculation magnetic separator 10.
[0055]
On the other hand, when the raw water having the SS
concentration of 10 mg/L flows into the raw water supply pipe 12,
the flocculation magnetic separator 10 has enough treatment
ability for treating the raw water by room of the ability of
treating the raw water with the SS concentration of 40 mg/L
compared to the raw water with the maximum SS concentration of
50 mg/L.
As a result, it is no problem to return the amount of the
collected flocs corresponding to the remaining room of the
treating ability of the flocculation magnetic separator 10.
[0056]
In a trial calculation, when the flocculation magnetic
separator 10 in FIG. 2 is used for the treatment of raw water,
the relationship among the SS concentration in raw water (A)
(mg/L), the returnable amount of the collected flocs (B) (return
rate (%) of the collected floc amount per the discharged floc
amount), and the addition amount of the brand-new magnetic powder
(C) (mg/L) is shown in a graphic diagram of FIG. 4, and in Table
1 listed below.
Herein, the graphic diagram in FIG. 4 and Table 1 show a
returnable amount of the collected flocs when the maximum designed
SS concentration in raw water is 50 mg/L.
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[0057]
In the graphic diagram of FIG. 4, the vertical axis
represents a rate of the magnetic powder contained in the flocs
at the just prior time to be returned to the magnetic separator
unit 16. The horizontal axis represents a return rate of the
collected flocs per the discharged amount.
Further, the lowest limited value of the magnetic powder rate
in the flocs is set in 31.4%. Here, the return rate of the flocs
and the addition amount of the brand-new magnetic powder are set
so that the magnetic powder rate becomes 31.4% or more in order
to effectively perform the magnetic separation by the magnetic
separation unit 16.
[0058]
Note the return rate of the flocs and the addition amount
of the brand-new magnetic powder are set in 31.4% in the present
embodiment. More specifically, as shown in Table 1, when the SS
concentration in raw water is 50 mg/L, the flocculation magnetic
separator 10 does not return the collected flocs, while the
separator 10 adds only brand-new magnetic powder by the
concentration of 30 mg/L. The SS concentration in raw water is
detected by the SS concentration meter 40, and the flocculation
magnetic separator 10 controls the return rate of the collected
flocs and the addition amount of the brand-new magnetic powder
corresponding to the detected data thus measured as shown in Table
1.
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[0059]
Further, when the flocculation magnetic separator 10 is
applied to a treatment of ballast water, the maximum SS
concentration in raw water is designed to have a value of 50 mg/L,
following the regulations of the IMO. However, since the actual
SS concentration in seawater often has a value less than 10 mg/L,
the return process of the collected flocs to the raw water supply
pipe 12 as set as mentioned above allows the used amounts of the
brand-new magnetic powder to be reduced.
This also enables the storage amounts necessary for the
brand-new magnetic powder to be reduced, resulting in greatly
advantageous merits to a ship of which inside space for arranging
multiple devices is significantly limited. Note plankton and
bacteria (viable individual) are set for a removal target in a
treatment of ballast water. Therefore, when the collected flocs
are returned to the raw water supply pipe 12, a heat sterilization
unit 22 is arranged in a return pipeline, thereby to return the
collected flocs as sterilizing the plankton and bacteria.
[0060]
Table 1.
A
50 0 (NOT RETURNABLE) 30
40 16 26
31 21
20 47 16
10 62 12
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[0061]
On the other hand, the injection amounts of the brand-new
magnetic powder are controlled by the control unit 24 through
adjusting the rotational rate of the magnetic powder injection
pump 38. Herein, the control operation is conducted in the range
from 0 to 100%, in which a rate of 100% (that is, 30 mg/L) calculated
by the injection amount of the brand-new magnetic powder
represents a case that no collected flocs are returned to the raw
water supply pipe 12. The injection amounts of the brand-new
magnetic powder are determined by the return amounts of the
collected flocs. For example, when the return amount of the
collected flocs per discharged amount is 47%, the magnetic powder
which flows into the high speed stirring tank 26 is to be returned
in 47% thereof. Hereby, the injection amounts of the brand-new
magnetic powder may be set in about 53% (or 16 mg/L).
The return amounts of the collected flocs are detected by
a flowmeter 74 which is arranged in the return pipeline for the
collected flocs. Based on the measurement results of the
flowmeter 74, the control unit 24 adjusts the rotational rate of
the pump 38, thereby to adjust the injection amounts of the
brand-new magnetic powder.
[0062]
Here, the flocculation magnetic separator 10 in FIG. 2
cannot return the collected flocs, if the SS concentration in raw
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water is larger than the maximum designed SS concentration in raw
water. Therefore, even in such a case, in order to return the
collected flocs thereby to recycle the magnetic powder component
in the collected flocs, it is needed to extract only a magnetic
powder component from the collected flocs and remove other SS
components, in the return process.
[0063]
Next, the flocculation magnetic separator 10 in FIG. 3 shows
an arrangement of the units. Herein, a magnetic powder extraction
unit 20 is arranged at a downstream position of a magnetic
separation unit 16 and a heat sterilization unit 22 is arranged
at a downstream position of the magnetic powder extraction unit
20.
[0064]
That is, the flocculation magnetic separator 10 in FIG. 3
represents an embodiment in which the magnetic powder extraction
unit 20 is arranged at an upstream position in a return passage
of the magnetic flocs; the return process being conducted by the
return and addition unit 18, while the heat sterilization unit
22 is arranged at a downstream position in the return passage.
[0065]
The magnetic powder extraction unit 20 separately performs
the treatment of the collected flocs which have been discharged
from the magnetic separation unit 16 through the following two
stages of the steps of: extracting the magnetic powder component
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contained in the collected flocs, and removing other SS components,
from the collected flocs.
[0066]
The first stage includes the steps of: crushing collected
flocs by applying physical force to the collected flocs. In the
collected flocs, a magnetic powder component and other SS
components are tightly agglomerated by an inorganic flocculant
and a polymer flocculant. Accordingly, a line mill 52 and/or a
supersonic wave crusher 54 are/is used so as to crush such tightly
agglomerated flocs.
Note it is experimentally determined that collected flocs
thus tightly agglomerated are decomposed to be almost crushed,
via a crushing treatment thereof for several 10 seconds to several
minutes conducted by the lime mill 52 and/or the supersonic wave
crusher 54.
[0067]
Here, a method for adjusting a pH value using a chemical
as described in the patent document 2 may be conducted so as to
facilitate the collected flocs to be decomposed. However, when
the treatment is conducted in a ship, it is preferable to decompose
the collected flocs via only a physical method, taking the IMO
regulations or the like in consideration.
[0068]
The second stage includes the steps of: extracting only a
magnetic powder component from the collected flocs thus crushed
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by magnetic force. As an extracting unit 56 (see FIG. 1), a unit
using a magnetic disk or a magnetic drum both in which permanent
magnets are embedded. Then, the second stage further includes
the steps of: diluting the extracted magnetic powder component
with clear water 66 (see FIG. 1); and returning the magnetic powder
component to the raw water supply pipe 12 (see FIG. 1) by the pump
58 (see FIG. 1).
[0069]
Though the two stages of the steps, the purity of the
magnetic powder component to be returned is increased. This
increase in the purity allows the collected flocs mainly
containing the magnetic powder component to be returned even
though the SS concentration in raw water becomes higher.
[0070]
Here, a trial calculation is conducted assuming the case
that the SS components other than the magnetic powder component
are separated from 30% of the collected flocs. Accordingly, in
the case of the flocculation magnetic separator 10 of FIG. 3, the
relationships among SS concentration in raw water (A) (mg/L),
returnable amounts of the collected flocs (B) (this is represented
by the return rate % of the collected flocs per discharged amounts
of collected flocs) , and addition amounts of the brand-new
magnetic powder (C) (mg/L) , are represented by the graphic diagram
in FIG. 5 and Table 2.
[0071]
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The above mentioned results demonstrate that the
flocculation magnetic separator 10 of FIG. 3 can more increase
the return rate of the collected flocs corresponding to the SS
concentration in raw water and reduce the addition amounts of
the bran-new magnetic powder than the flocculation magnetic
separator 10 having no magnetic powder extraction unit 20 of FIG.
2.
[0072]
Table 2.
A
50 0 (NOT RETURNABLE) 30
40 19 25
30 42 18
65 11
10 87 4
[ 0073]
Further, if 30% of the SS components other than the magnetic
powder component contained in the collected flocs are separated
and removed from collected flocs by the magnetic powder extraction
unit 20, this results in the condition that the collected flocs
originally contain the SS concentration in raw water of 30 mg/L.
Hereby, this SS concentration allows 42% of the discharged
collected flocs to be returned.
Accordingly, it is preferable to arrange the magnetic
powder extraction unit 20 in the flocculation magnetic separator
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10, if the SS concentration in raw water is often higher than the
maximum designed SS concentration in raw water, or if more amounts
of the collected flocs are returned so as to reduce the used amounts
of the brand-new magnetic powder to be also reduced.
[0074]
[Additional Remarks]
[Explanation on Optimal Value of Magnetic Powder Rate in
Magnetic Flocs]
Here, it is noted that treatment targets for treating
ballast water include plankton and bacteria. In addition to this,
if a ballast water treatment system is installed in a ship, it
is needed to pass a test for checking the treatment performance
of the system or regulations, as defined by the regulatory agency.
According to the regulations, the treatment system is demanded
to have the performance enough to treat the ballast water
containing the suspended solids (SS) such as sand in the ballast
water with the maximum concentration of 50 mg/L, with satisfying
the discharging criteria on ballast water.
[0075]
In this regard, the present inventors adopt a method for
adding mineral based micro particles called kaolin as a simulant
of sand or the like in the test for determining conditions in the
flocculation magnetic separation of plankton and bacteria.
Hereinafter, more specifically will be explained the test
method in detail.
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[0076]
First, to sea water containing plankton and bacteria, is
added the above mentioned kaolin in the concentration of 50 mg/L.
Then, a flocculation test of the seawater is conducted by setting
parameters (or variables) to include the addition rates of
magnetic powder, an inorganic flocculant and a polymer flocculant.
After that, formation state of the magnetic flocs is evaluated
by visual observation. Next, the seawater containing the
magnetic flocs is introduced into a channel in which permanent
magnets are placed in order. The sea water was subjected by a
contact treatment and an adsorption treatment with the magnets
for a predetermined time (or several seconds). Then, the
concentration of the magnetic flocs in the sea water discharged
from the channel is measured, whereas the removal rate of the
magnetic flocs is determined.
[0077]
The results in the evaluation test as mentioned above
clearly indicate that plankton and bacteria are sufficiently
flocculated under the condition of the addition rates: poly
aluminum chloride used as an inorganic flocculant = 5 mg Al/L;
and polymer flocculant = 1 mg/L.
[0078]
Further, as shown in FIG. 6, the removal rate of the magnetic
flocs is likely to increase, as the addition rate of the magnetic
powder increases. When the addition rate of the magnetic powder
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becomes 30 mg/L or more, the removal rate is likely to reach a
peak. From the viewpoint of costs, it is desirable to decrease
the addition rate of the magnetic powder as many as possible.
Hereby, the addition rate of the magnetic powder is determined
to be 30 mg/L.
[0079]
If the addition rates of the magnetic powder, the inorganic
flocculant and the polymer flocculant are set in the values as
mentioned above, the content of the magnetic powder per magnetic
flocs may be calculated by the following formula.
[0080]
Content of Magnetic Powder in Magnetic Flocs (%) =
(Addition Rate of Magnetic Powder) / (Addition Rate of Kaolin
+ Addition Rate of Magnetic Powder + Addition Rate of Inorganic
Flocculant + Addition Rate of Polymer Flocculant) x 100 ---
(Formula 1)
Here, each value is listed as follows. Addition Rate of
Magnetic Powder - 30 mg/L; Addition Rate of Kaolin = 50 mg/L;
Addition Rate of Inorganic Flocculant = 5 x (78/27) = 14.4 mg/L;
Addition Rate of Polymer Flocculant = 1 mg/L.
Note poly aluminum chloride added as an inorganic
flocculant exists in the form of aluminum hydroxide (Al(OH)3) in
the magnetic flocs. Therefore, the addition rate of the poly
aluminum chloride is calculated by the formula of: 5 mg Al/L
(addition rate) x 78 (MW of Al(OH)3)/ 27 (AW of Al).
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If the respective values are substituted in Formula 1, the
formula is represented as:
Content of Magnetic Powder in Magnetic Flocs (%) =
30 / (50 + 30 + 14.4 + 1) x 100 = 31.4 (%)
The present inventors determine that this calculated rate
of the magnetic powder is the optimal value which allows the
removal rate of the magnetic flocs to be secured and the treatment
costs to be minimized.
[0081]
As mentioned hereinbefore, it should be noted that a recycle
method of magnetic powder needs to construct a treatment flow of
magnetic powder so as to secure the removal rate of magnetic flocs
and maintain the treatment performance thereof, without lowering
the content of the magnetic powder less than the value as
calculated above.
[0082]
Further, a graphic diagram in FIG. 7 shows a return rate
of the collected flocs per SS in raw water (mg/L). A return rate
of the collected flocs is set based on the graph.
DESCRIPTION OF REFERENCE NUMERALS
[0083]
10: Flocculation Magnetic Separator
12: Raw Water Supply Pipe
14: Flocculation Unit
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16: Magnetic Separation Unit (or Magnetic Separation
Device)
18: Return and Addition Unit (or Return and Addition
Device)
20: Magnetic Powder Extraction Unit (or Magnetic Powder
Extraction Device)
22: Heat Sterilization Unit (or Heat Sterilization
Device)
24: Control Unit (or Control Device)
26: High Speed Stirring Tank (or First Stirring Tank)
28 Low Speed Stirring Tank (or Second Stirring Tank)
30: Magnetic Powder Supply Unit (or Magnetic Powder
Supply Device)
32: Flocculant Addition Unit
34: Pipeline
36: Polymer Flocculant Addition Unit
38: Magnetic Powder Injection Pump
40: SS Concentration meter (or Concentration Detection
Device)
42: Collected Flocs Return Pump
44: Magnetic Separation Tank
46: Magnetic Filter
48: Conveyer
50: Collected Floc Receiver Tank
52: Crush unit (or Crush device: Line Mill)
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54 Crush unit (or Crush Device: Supersonic Wave Crusher)
56: Extraction Unit (or Extraction Device)
58: Pump (or Return Device)
60: Stirring Blade
62: Vibrator
64: Liquid
65: Ball Mill (Crush Unit)
66: Clear Water
68: Tank
70: Filter
72: Pipeline
74: Flowmeter
20
P35025

Representative Drawing
A single figure which represents the drawing illustrating the invention.
Administrative Status

For a clearer understanding of the status of the application/patent presented on this page, the site Disclaimer , as well as the definitions for Patent , Administrative Status , Maintenance Fee  and Payment History  should be consulted.

Administrative Status

Title Date
Forecasted Issue Date 2016-01-12
(86) PCT Filing Date 2012-01-26
(87) PCT Publication Date 2012-08-02
(85) National Entry 2013-07-24
Examination Requested 2013-07-24
(45) Issued 2016-01-12
Deemed Expired 2018-01-26

Abandonment History

There is no abandonment history.

Payment History

Fee Type Anniversary Year Due Date Amount Paid Paid Date
Request for Examination $800.00 2013-07-24
Application Fee $400.00 2013-07-24
Maintenance Fee - Application - New Act 2 2014-01-27 $100.00 2014-01-27
Maintenance Fee - Application - New Act 3 2015-01-26 $100.00 2015-01-05
Final Fee $300.00 2015-10-29
Maintenance Fee - Application - New Act 4 2016-01-26 $100.00 2016-01-05
Owners on Record

Note: Records showing the ownership history in alphabetical order.

Current Owners on Record
HITACHI, LTD.
Past Owners on Record
None
Past Owners that do not appear in the "Owners on Record" listing will appear in other documentation within the application.
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Document
Description 
Date
(yyyy-mm-dd) 
Number of pages   Size of Image (KB) 
Abstract 2013-07-24 1 22
Claims 2013-07-24 4 90
Drawings 2013-07-24 7 102
Description 2013-07-24 40 1,221
Representative Drawing 2013-10-08 1 13
Cover Page 2013-10-08 2 50
Description 2015-07-03 41 1,267
Claims 2015-07-03 4 102
Abstract 2015-12-17 1 22
Representative Drawing 2015-12-24 1 11
Cover Page 2015-12-24 1 47
Change of Agent 2017-10-11 1 36
Office Letter 2017-10-18 1 23
Office Letter 2017-10-18 1 31
PCT 2013-07-24 18 704
Assignment 2013-07-24 5 132
Fees 2014-01-27 1 56
Prosecution-Amendment 2015-01-14 3 235
Fees 2015-01-05 1 58
Amendment 2015-07-03 21 749
Final Fee 2015-10-29 2 56