JP2008018319A - Attraction and removal method of suspended particle, and attraction and removal apparatus therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an attraction and removal method of suspended particles by which the suspended particles incorporated in the treating liquid can efficiently be separated and removed and magnetic particles used for separating and removing the suspended particles can easily be removed separately from the suspended particles, and to provide an attraction and removal apparatus for the suspended particles used for the method. <P>SOLUTION: The attraction and removal method of suspended particles comprises processes for: forming flock by charging magnetic particles and a flocculant into a liquid containing suspended particles and including the suspended particles and magnetic particles therein; attracting the flock to a rotary drum by magnetism while rotating the magnetized rotary drum with part of which dipped in the flock mixed liquid obtained in the flock forming process; and removing the flock attracted on the rotary drum from the rotary drum at a part above the draft level at the rear side in the rotation direction from the highest point of the rotary drum. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a method for adsorbing and removing suspended particles that can efficiently remove suspended particles from a liquid to be treated containing suspended particles such as hardly settled particles such as red soil, and an adsorbing and removing apparatus used for the adsorption and removal method.

For example, in the case of a soil with a fine particle size such as red soil on the main island of Okinawa, it is eroded by rainfall and often flows into a sedimentation basin at a concentration of 2000 ppm or more, but a component with a particle size of 20 μm or less occupies 50% or more. Because of its fine particle size, natural sedimentation does not sufficiently settle for several hours, and it cannot stop the outflow to rivers and oceans.
In addition, the red soil called Kunigami Marge, which is often found in the northern part of the main island of Okinawa, is strongly acidic, so when the red soil enters the seawater, the pH of the seawater is lowered, the sea becomes acidic and aluminum ions are leached, which causes coral to dissolve. There is a risk that sea creatures such as will be sustained.

On the other hand, there is a method of coagulating and precipitating the hardly sedimentable fine particles using a flocculant as a method for purifying the suspended water containing the hardly sedimentable fine particles at an early stage.
However, when PAC (polyaluminum chloride), which is generally used as a flocculant, is used, a large amount of PAC is required because of the small PAC cohesive force, and fine pH adjustment is also required. Etc., which are cumbersome and inefficient.

  Therefore, the inventor of the present invention puts magnetic particles together with an aggregating agent, aggregates the magnetic particles together with floating particles such as hard-to-set particles, and covers a floc containing the formed floating particles and magnetic particles. It was thought that the suspension water could be efficiently purified by using a small amount of flocculant if it was adsorbed and removed from the treatment liquid with a magnet.

  By the way, as an apparatus for adsorbing and removing magnetic particles from a liquid to be treated, a rotating drum containing a permanent magnet is arranged in a processing tank in which a liquid to be treated containing magnetic particles is accommodated, and the surface of the rotating drum is arranged. The part is rotated while being immersed in the liquid to be treated, and the sludge containing magnetic particles is adsorbed on the surface of the rotating drum, and then this sludge is pressed and dehydrated by a squeezing roller contacting the surface of the rotating drum. Disclosed is a method for separating and removing magnetic particles from a liquid to be treated by scraping a dewatered sludge containing magnetic particles remaining adsorbed on the surface with a sludge stripping plate in contact with the surface of the rotating drum. (For example, refer to Patent Document 1).

  In addition, a processing tank for storing the liquid to be processed, a cylinder having a tip disposed in the processing tank and provided to be inclined with respect to the processing tank, and a magnet that reciprocally moves inside the cylinder, After adsorbing and collecting the harmful substances in the liquid to be treated, the granulated particles containing zeolite particles and magnetic particles are adsorbed on the magnet, An apparatus for separating and removing harmful substances from a liquid to be treated is disclosed. (For example, refer to Patent Document 2).

  However, in the former suction removing device, the squeezing roller is disposed on the front side in the rotational direction of the rotating drum from the highest position on the surface of the rotating drum, so that the waste water generated by the dewatering treatment by the squeezing roller is again, It will be returned to the processing tank. Therefore, although it is suitable for separating and removing magnetic particles, floating particles other than magnetic particles cannot be separated and removed from the liquid to be treated.

In addition, the latter device adsorbs the granulated particles collecting harmful substances to the magnet and moves them outside the processing tank, and then separates and removes the granulated particles collected harmful substances. Not only the magnetic particles are separated and removed together. Therefore, although it is suitable for the separation and removal of harmful substances, there is a drawback that it is difficult to separate and recover the magnetic particles and it is difficult to reuse the magnetic particles.
Japanese Patent Laid-Open No. 10-24249 JP 2005-177709 A

  The present invention has been made in view of the above problems, and can efficiently separate and remove suspended particles contained in a liquid to be treated, and easily separate magnetic particles used for separating and removing suspended particles separately from suspended particles. It is an object of the present invention to provide a method for adsorbing and removing suspended particles that can be separated and recovered and a device for adsorbing and removing suspended particles used in this method.

  In order to achieve the above object, the method for adsorbing and removing suspended particles according to claim 1 of the present invention (hereinafter referred to as the “adsorbing and removing method of claim 1”) comprises aggregating magnetic particles and liquid particles in a liquid containing suspended particles. A floc forming process in which an agent is added to form a floc formed by entraining suspended particles and magnetic particles, and a magnetized rotating drum is partially immersed in the floc mixture obtained in the floc forming process. A suction step in which the floc is attracted to the rotating drum by a magnetic force while rotating in a rotating state, and the floc adsorbed on the rotating drum is removed from the rotating drum at a position above the draft surface behind the highest point of the rotating drum in the rotational direction. And a floc removing process.

  In the method for adsorbing and removing suspended particles according to claim 2 of the present invention (hereinafter referred to as “adsorption and removing method of claim 2”), the floc removing step pushes a portion other than the magnetic particles contained in the floc to the rotating drum. It is characterized by comprising a step of squeezing with a squeezing roller applied and a step of removing magnetic particles remaining on the surface of the rotating drum from the surface of the rotating drum.

  The adsorbing and removing method for suspended particles according to claim 3 of the present invention (hereinafter referred to as “adsorbing and removing method of claim 3”) recycles the magnetic particles removed and collected from the rotating drum in the flock formation step. It is a feature.

  The method for adsorbing and removing suspended particles according to claim 4 of the present invention (hereinafter referred to as “adsorption and removing method of claim 4”) is characterized in that the suspended particles are soil particles.

  The adsorbing and removing apparatus for suspended particles according to claim 5 of the present invention (hereinafter referred to as "adsorbing and removing apparatus according to claim 5") is an apparatus used for the adsorbing and removing method according to any one of claims 1 to 4. A part of the surface of the rotating drum is covered with a processing tank for containing a floc mixed liquid containing flocks in which suspended particles and magnetic particles are entrained, and a rotating shaft in a horizontal direction above the processing tank. A rotating drum disposed so as to be immersed in the processing liquid, and a squeezing roller that contacts the surface of the rotating drum at a position rearward in the rotational direction from the highest point of the rotating drum and above the draft surface of the rotating drum; Of the surface of the rotating drum, at least the portion behind the squeezing roller in the rotational direction and excluding the position above the draft surface of the rotating drum is magnetized so that at least the flock can be attracted by magnetic force. It is characterized in.

  The adsorbing / removing device for suspended particles according to claim 6 of the present invention (hereinafter referred to as “adsorbing / removing device according to claim 6”) is the adsorbing / removing device according to claim 5, wherein the squeezing roller of the surface of the rotating drum The portion further in the rotational direction and excluding the position above the draft surface of the rotating drum is in a weakly magnetized state or a non-magnetized state in which the magnetic particles are not attracted. The tip of the removal blade for removing the adsorbate on the surface of the rotating drum is in contact with the surface of the rotating drum in the state.

  The suspended particle adsorption / removal device according to claim 7 of the present invention (hereinafter referred to as "adsorption / removal device according to claim 7") is the adsorption removal device according to claim 5 or 6, wherein the highest point of the squeeze roller is rotated. It is characterized by being placed at a position lower than the highest point of the drum.

  In the present invention, the magnetic particles are not particularly limited, and examples thereof include particles of Fe, Co, Ni, and the like. Although it does not specifically limit as a particle size of a magnetic body particle, About 0.2-0.6 micrometer is preferable.

  The flocculant is not particularly limited, and examples thereof include inorganic flocculants and organic polymer flocculants. The organic polymer flocculant may be any of cationic, anionic and nonionic. However, if the cohesive force is too strong, the flocculant and the magnetic particles / soil particles cannot be separated later.

  In addition, the highest point of the rotating drum is a point on the surface of the rotating drum that is the highest position from the ground. Similarly, the highest point of the squeezing roller is the point on the surface of the squeezing roller that is the highest position from the ground.

  According to the adsorption removal method of claim 1, the magnetic particle and the flocculant are added to the liquid containing the suspended particles, and the floc forming step of forming the floc formed by entraining the suspended particles and the magnetic particles is magnetized. Rotating the rotating drum from the highest point of the rotating drum, while rotating the rotating drum in a state where a part of the rotating drum is immersed in the floc mixture obtained in the floc forming process, The floc removal process removes the floc adsorbed on the rotating drum from the rotating drum at a position above the draft surface at the rear of the direction, so that the floc in the flock mixed liquid returns to the flock mixed liquid side from the rotating drum. Can be removed efficiently without any problems.

  According to the adsorption removal method of claim 2, the floc removal step includes a step of squeezing with a squeezing roller that presses a portion other than the magnetic particles contained in the flock against the rotating drum, and the magnetic particles remaining on the surface of the rotating drum. And removing the floc from the surface of the rotating drum, when removing the floc from the floc mixture, it is possible to individually remove portions other than the magnetic particles contained in the floc and the magnetic particles. That is, suspended particles and magnetic particles can be removed individually.

  According to the adsorption removal method of the third aspect, since the magnetic particles removed and collected from the rotating drum are reused in the flock forming step, the magnetic particles can be repeatedly and semi-permanently used in the flock forming step. Therefore, it is possible to effectively use limited resources and reduce running costs.

  According to the adsorption removal method of the fourth aspect, since the suspended particles are soil particles, the soil particles can be separated and removed from the suspended water of the soil particles. Therefore, for example, before the fine-grained soil that does not naturally settle out flows into rivers and oceans due to heavy rain, etc., these soil particles are adsorbed and removed by the adsorption removal method of the present invention, causing damage such as marine pollution. Can be effectively prevented. In addition, by removing and removing soil particles contained in rainwater stored in the water storage facility, the rainwater can be purified and used as intermediate water such as industrial water.

  According to the adsorption removal apparatus of claim 5, a processing tank for containing a floc mixed liquid containing a floc formed by entraining suspended particles and magnetic particles, and a rotating shaft in a horizontal direction above the processing tank, A rotating drum arranged so that a part of the surface of the rotating drum is immersed in the floc mixture, and on the surface of the rotating drum at a position rearward in the rotational direction from the highest point of the rotating drum and above the draft surface of the rotating drum. A portion of the surface of the rotating drum excluding the position behind the squeezing roller and in the rotational direction and above the draft surface of the rotating drum so that at least the floc can be attracted by a magnetic force. Therefore, when the floc contained in the floc mixture is adsorbed on the surface of the rotating drum, the rotating drum rotates more than the highest point of the rotating drum. After transporting to the contact portion with the squeezing roller provided at the rear, the part other than the magnetic particles contained in the flock can be squeezed out by the squeezing roller, and the magnetic particles are rotated while adsorbed on the surface of the rotating drum. The contact portion between the drum and the squeezing roller can be passed. Therefore, the floc can be reliably removed from the floc mixture, and the suspended particles and the magnetic particles contained in the floc can be separately separated and removed.

  According to the adsorption removal apparatus of claim 6, a portion of the surface of the rotating drum that is behind the squeezing roller in the rotation direction and excluding the position above the draft surface of the rotating drum is weakly magnetized so as not to adsorb magnetic particles. Since the tip of the removal blade that removes the adsorbate on the surface of the rotating drum is in contact with the surface of the rotating drum in the weakly magnetized state or the non-magnetized state, After being conveyed to the rear in the rotational direction from the roller, the magnetic particles that have become non-adsorbed with respect to the rotating drum can be easily and reliably scraped off by the blade edge of the removal blade along the surface of the rotating drum.

  Further, when the highest point of the squeeze roller is arranged at a position lower than the highest point of the rotating drum, a portion other than the magnetic particles contained in the flock accumulates to some extent on the contact portion between the rotating drum and the squeezing roller. Since the highest point of the squeezing roller is naturally overcome, if it is received by a tray or the like, it is possible to recover the portion other than the magnetic particles contained in the flock, that is, suspended particles without using a special removing means. .

  An embodiment of the method for adsorbing and removing suspended particles according to the present invention will be described in detail with reference to the drawings.

In the adsorption removal method of the present embodiment, as shown in FIG. 1, first, suspended water 100 containing fine grained soil such as red soil flowing out from a mountain or the like is stored in a sand basin 101 and easily settled in the suspended water 100. Large foreign matter 102 such as rough sand or crushed stone is settled in the sand basin 101, and the suspended water 103 containing only the fine particle size soil as floating particles remaining as the supernatant is transferred to the pretreatment tank 104.
Although it does not specifically limit as a sand basin, For example, the product name rain made by Sekisui Chemical Co., Ltd. which can be formed by combining a plurality of synthetic resin inclined plates disclosed in JP-A-2005-179919 in multiple stages. It is preferable to form using a station.
Then, the magnetic particles M and the flocculant N1 are added to the suspended water 103 transferred to the pretreatment tank 104, and after stirring once, the pH adjuster R is charged as necessary, and then the flocculant N2 is further charged. And agitation is performed to form a floc F comprising finely sized soil and magnetic particles.

Next, the floc mixture W obtained in the flock formation step is put into the adsorption removal device 1, and the magnetized rotating drum 3 is rotated while being partially immersed in the floc mixture W. The flock F is attracted to the rotating drum 3 by a magnetic force. Thereafter, by the squeezing roller 4 arranged so as to be pressed against the rotating drum 3, the portion other than the magnetic particles M included in the flock F, that is, the deposit T made of fine-grained soil containing moisture is separated, The magnetic particles M remaining on the surface of the rotating drum are removed from the surface of the rotating drum 3. The collected magnetic particles M are reused in the floc forming step as necessary.
In addition, specific embodiment of the adsorption removal apparatus 1 and its effect are mentioned later.

  For example, as shown in FIG. 1, as a disposal method of the deposit T composed of water-containing fine particle size soil, it is sucked and collected by a vacuum suction device V and dehydrated by a dehydrator or a cyclone separator, The dehydrated cake C is further formed by a press or the like, transported to a disposal site such as a landfill, and discarded.

Next, a specific embodiment of the adsorption removal apparatus 1 used in the adsorption removal method of the present invention will be described in detail with reference to the drawings.
As shown in FIG. 2, the adsorption removal apparatus 1 a of the present embodiment is disposed above the processing tank 2 for containing the flock mixed solution W and a rotating shaft (not shown) in the horizontal direction above the processing tank 2. The rotating drum 3, a squeezing roller 4 a that contacts the surface of the rotating drum 3, and a removal blade 5 disposed behind the squeezing roller 4 a in the rotation direction of the rotating drum 3 are provided.

  The processing tank 2 includes a mixed solution storage unit 21 for storing the flock mixed solution W, and a drainage storage unit for temporarily storing waste water after the floc F contained in the flock mixed solution W is adsorbed to the rotary drum 3. 22 and a drain outlet 23 for appropriately draining the drainage accommodated in the drainage accommodating part 22. The mixed liquid storage unit 21 and the drainage storage unit 22 are partitioned by a partition plate 24 installed perpendicular to the bottom surface of the processing tank 2. A curved plate 25 is provided at the upper end of the partition plate 24. The curved plate 25 is curved concentrically with the same radius of curvature as the rotating drum 3, and is disposed on the mixed liquid container 21 side as shown in FIG.

As shown in FIG. 2, the rotary drum 3 is provided above the curved plate 25 of the processing tank 2 with a predetermined interval so that a flow path is formed between the rotary drum 3 and the curved plate 25.
The rotating drum 3 incorporates a magnet 6 fixed to the processing tank 2 and can be rotated around the magnet 6 in the arrow X direction by a driving device (not shown).
The magnet 6 is substantially C-shaped in cross section, and is disposed between the draft surface A behind the drum in the rotation direction and the contact portion B with the squeezing roller 4a in the rotation direction of the rotary drum 3. Of the surface, the portion behind the squeezing roller 4a in the rotation direction and excluding the position above the draft surface A of the rotary drum 3 is magnetized so that the flock F can be attracted by a magnetic force.

  The squeezing roller 4 has a surface made of an elastic material such as rubber, and is behind the highest point P of the surface of the rotating drum 3 in the rotational direction of the rotating drum 3 and above the draft surface A of the rotating drum 3. Further, they are arranged in a state of being pressed against the surface of the rotary drum 3.

  The removal blade 5 is made of a nonmagnetic material, and is inclined so that the blade tip 51 side is high and the root side is low with the blade tip 51 being along the surface of the rotary drum 3.

  The flock liquid mixture W is formed in advance by introducing the magnetic particles M and the flocculants N1 and N2 into a liquid containing soil particles L such as red soil and other fine-grained soil. A floc F containing M is contained, and a part of the surface of the rotary drum 3 is introduced into the processing tank 2 up to a water level at which the floc mixture W is immersed.

Next, a procedure for removing the soil particles L and the magnetic particles M from the floc mixture W using the apparatus of the present embodiment will be described.
First, the rotating drum 3 is continuously rotated in the rotation direction shown in FIG. 2, and the flock F contained in the flock mixed solution W is adsorbed to the portion of the surface of the rotating drum 3 immersed in the flock mixed solution W.
The flock F adsorbed on the surface of the rotating drum 3 is conveyed while adsorbed to the rotating drum 3 as the rotating drum 3 rotates, and after reaching the highest point P of the rotating drum 3, it is pressed against the rotating drum 3. However, a portion other than the magnetic particles M included in the flock F, that is, the deposit T containing moisture and soil particles L is squeezed out by the squeezing roller 4a that rotates.
On the other hand, the magnetic particles M contained in the flock F remain on the surface of the rotating drum 3 and pass through the contact portion B with the squeezing roller 4a, and then are scraped and collected from the surface of the rotating drum 3 by the removing blade 5. The
The recovered magnetic particles M are reused in the process of forming the floc F. Further, the deposit T squeezed out before the contact portion B between the rotary drum 3 and the squeezing roller 4a is removed and collected by, for example, a vacuum suction device V or a brush (not shown).

As described above in detail, according to the apparatus 1a according to the present embodiment, the soil particles L and the magnetic particles M can be easily and reliably separated and removed from the floc F in the floc mixed liquid W.
Further, by arranging the magnet 6 having a substantially C shape in cross section in the rotation direction of the rotary drum 3 between the draft surface A at the rear of the drum rotation direction and the contact portion B with the squeezing roller 4a, the squeezing roller The part behind the rotational direction 4a and excluding the position above the draft surface A of the rotating drum 3 is in a weakly magnetized state or a non-magnetized state in which the magnetic particles M are not attracted. Can be easily and reliably scraped.
Further, since the removal blade 5 is disposed so as to be inclined so that the cutting edge 51 is high and the root portion is low, the magnetic particles M deposited on the cutting edge 51 of the removal blade 5 are slid on the blade by its own weight. It can be easily recovered.

Next, a second embodiment of the adsorption removal apparatus 1 used in the adsorption removal method of the present invention will be described in detail with reference to the drawings.
Since the suspended particle adsorption / removal device 1b according to the present embodiment has basically the same configuration as the device 1a according to the first embodiment, the same parts as those in the first embodiment are denoted by the same reference numerals. Detailed description is omitted.

As shown in FIG. 3, the apparatus 1 b of the present embodiment is provided such that the highest point Q of the squeezing roller 4 b is disposed at a position lower than the highest point P of the rotary drum 3.
Further, behind the squeezing roller 4b, a collection blade 7 that collects the deposit T deposited before the contact portion B between the rotary drum 3 and the squeezing roller 4b brings the cutting edge 71 along the surface of the squeezing roller 4b. It is provided in the state.
The collection blade 7 is made of a non-magnetic material, and is inclined so that the cutting edge 71 side is high and the root side is low, with the cutting edge 71 being along the surface of the rotary drum 3.

Therefore, according to the apparatus 1b of the present embodiment, in addition to the effects of the present invention, the deposit T deposited before the contact portion B between the rotating drum 3 and the squeezing roller 4b is used as the highest point of the squeezing roller 4b. It is possible to get over and guide to the cutting edge 71 side of the collection blade 7. Therefore, a portion other than the magnetic particles M included in the floc F, that is, the deposit T including the suspended particles F can be recovered without using any special removing means.
Further, the deposit T deposited on the cutting edge 71 of the recovery blade 7 can be easily recovered by sliding on the blade by its own weight.

  In the embodiment described above, soil particles L having a fine particle size such as red soil are taken as an example of suspended particles. However, this is an example of suspended particles and is not limited thereto. Therefore, for example, fine particles included when rainwater is collected may be used.

  Further, the magnet 6 used may be a permanent magnet such as ferrite (Ba, Sr), rare earth neodymium (Ne-Fe-B), rare earth samarium-cobalt (Sm-Co), or an electromagnet. I do not care.

  In the second embodiment, the collection blade 7 is not always necessary. When the deposit T deposited before the contact portion B between the rotating drum 3 and the squeezing roller 4b exceeds a predetermined amount and climbs over the highest point of the squeezing roller 4b, the deposit T that falls over and falls is received. As long as it can be collected.

    Next, specific examples of the present invention will be described.

(Example)
The floc mixture W was obtained by the following procedure.
1) 20 g of magnetite (product name: iron black pigment SL, manufactured by Mitsui Kinzoku Mining Co., Ltd.) was added and stirred as a magnetic particle to 10 liter of soil particle turbid liquid (containing 200 mg of soil particles / liter).
2) 100 ml of polyferric sulfate (product name: Danpower) manufactured by Taki Chemical Co., Ltd. was added as a flocculant and stirred.
3) About 100 milliliters of an 8 molar potassium hydroxide solution was added to adjust the pH of the solution to around 7.
4) A cationic polymer flocculant (manufactured by Sanyo Kasei Kogyo Co., Ltd., product name: Sanfloc) 0.1% solution 100 ml as a coagulant aid was added and stirred.
5) The liquid after stirring was allowed to stand for several minutes to obtain a floc mixed liquid W in which a block F in which soil particles L and magnetic particles M were involved was formed.
And the floc liquid mixture W obtained by the said procedure was thrown into the adsorption removal apparatus 1a which is the 1st Embodiment of this invention. The rotating drum 3 has an outer diameter of 102 mm, a width of 315 mm, and is operated at a rotational speed of 6 times / minute in a state where it is immersed in the flock mixed solution W at a depth of 25 mm. And recovered.
The solid content weight of the waste water from the drain pipe 23 was measured and found to be 30 mg / liter.

It is a schematic diagram which illustrates typically an example of the adsorption removal method of the floating particle concerning this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which illustrates typically the adsorption removal apparatus 1a of the suspended particle which is 1st Embodiment concerning this invention. It is the schematic diagram which expands and principally demonstrates the principal part of the adsorption removal apparatus 1b of the suspended particle which is 2nd Embodiment concerning this invention.

Explanation of symbols

1 (1a, 1b) Suspended particle adsorption / removal device 2 Processing tank 3 Rotating drum 4 (4a, 4b) Squeezing roller 5 Removal blade 7 Recovery blade W Flock mixture L Soil particles (floating particles)
M Magnetic particle F Flock A Draft surface B Abutting part of rotating drum and squeezing roller P Maximum point of rotating drum Q Maximum point of squeezing roller

Claims (7)

A flock formation step of forming a flock formed by introducing magnetic particles and a coagulant into a liquid containing floating particles and entraining the floating particles and the magnetic particles;
An adsorption step of adsorbing the floc to the rotating drum by a magnetic force while rotating the magnetized rotating drum in a state where a part of the rotating drum is immersed in the floc mixture obtained in the floc forming step;
A method for adsorbing and removing suspended particles, comprising: a floc removing step for removing from the rotating drum the floc adsorbed on the rotating drum at a position above the draft surface in the rotational direction behind the highest point of the rotating drum.   The floc removing step comprises a step of squeezing with a squeezing roller that presses a portion other than the magnetic particles contained in the floc against the rotating drum, and a step of removing magnetic particles remaining on the surface of the rotating drum from the surface of the rotating drum. The method for adsorbing and removing suspended particles according to claim 1.   The method for adsorbing and removing suspended particles according to claim 1 or 2, wherein the magnetic particles removed and collected from the rotating drum are reused in the flock formation step.   The method for adsorbing and removing suspended particles according to any one of claims 1 to 3, wherein the suspended particles are soil particles. A treatment tank for containing a floc mixture containing flocs comprising suspended particles and magnetic particles;
A rotating drum disposed above the processing tank so that a part of the surface of the rotating drum is immersed in the floc mixed liquid with the rotating shaft in the horizontal direction.
A squeezing roller that comes into contact with the surface of the rotating drum at a position rearward in the rotational direction from the highest point of the rotating drum and above the draft surface of the rotating drum;
The part of the surface of the rotating drum, which is behind the squeezing roller in the rotation direction and excluding the position above the draft surface of the rotating drum, is magnetized so that at least the flock can be attracted by a magnetic force. 5. An apparatus for adsorbing and removing suspended particles used in the method for adsorbing and removing suspended particles according to any one of 4   Of the surface of the rotating drum, the portion behind the squeezing roller in the rotational direction and excluding the position above the draft surface of the rotating drum is in a weakly magnetized state or a non-magnetized state in which the magnetic particles are not attracted. The suspended particle adsorption / removal device according to claim 5, wherein a tip of a removal blade for removing adsorbate on the surface of the rotating drum is in contact with the surface of the weakly magnetized or non-magnetized rotating drum.   The suspended particle adsorption / removal device according to claim 5 or 6, wherein the highest point of the squeezing roller is disposed at a position lower than the highest point of the rotating drum.

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