JP2005111424A - Method and apparatus for removing substance to be removed from fluid and sludge separation and recovery apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for removing substances to be removed from fluid and a sludge separation and recovery device which can recover recyclable materials from sludge and reduce the operation costs of the apparatus. <P>SOLUTION: A magnetic material and a coagulant are continuously supplied to raw water 1 to be stirred, thereby generating magnetic flocs 10. The magnetic flocs 10 are collected in a sludge recovery tank 11 by a magnetic separation and purification device having a mesh 6' having an aperture through which the magnetic flocs 10 cannot pass, a magnetic field generation means 8 for magnetically attracting the magnetic flocs 10, and a scraper 9 for recovering the flocs. In a sludge decomposition tank 12, hydrochloric acid 13 is added to the magnetic flocs 10 to be stirred, thereby decomposing the magnetic flocs. The treated liquid containing the decomposed magnetic flocs is subjected to gravity separation in a sedimentation tank 14, and the treated liquid containing magnetic powder and the coagulant is recycled. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method and apparatus for removing an object to be removed from a fluid that decomposes sludge and purifies water, and a sludge separation and recovery apparatus.

  For the purpose of water purification, a thin wire net or a net woven with polymer fibers is used as a separation membrane. A flocculant and magnetic powder are added to raw water with contaminated particles to generate magnetic floc, and the magnetic floc is formed with a membrane. There is a magnetic separation and purification device that collects high-concentration sludge by magnetic separation and removal of magnetic flocs separated and collected by a membrane by a magnetic field generating means. Such a separation and purification device is made of a mesh made of stainless steel fine wires or polyester fibers, and has a membrane separation part having an opening with an opening of several tens of micrometers, for example. In order to separate fine pollutants smaller than the opening, for example, flocculant vanous sulfate, polyaluminum chloride, iron chloride, and magnetic powder are added to the raw water and stirred, and fine solid suspension in the raw water A magnetic floc is formed by binding algae, algae, and microorganisms to a size of about several hundred micrometers using a flocculant. This magnetic floc cannot pass through an opening having an opening of several tens of micrometers, and is collected and separated at a high removal rate. The treated water that has passed through the membrane is further purified.

  Conventionally, the magnetic flocs collected on the membrane are washed away from the membrane with washing water, then stopped near the water surface, separated by the magnetic force of a magnet placed stationary near the water surface, and sludge collected by the sludge transfer means Stored in the tank. The sludge is eventually transported to a disposal site or incinerator by truck or composted.

JP 2002-273261 A

  In the above-described prior art, sludge such as magnetic floc (aggregated material aggregated by a coagulant) is discarded as it is, and no consideration is given to the reuse of resources.

  An object of the present invention is to provide a method and apparatus for removing an object to be removed from a fluid and a sludge separation and recovery apparatus that can recover what can be reused from sludge and reduce the operating cost of the apparatus.

  The purpose is to supply a flocculant made of a plurality of materials to a fluid to be treated containing the material to be removed, and to agglomerate the material to be removed to a predetermined size by the flocculant to form an aggregated material. The agglomerated material is separated and recovered from the product, a decomposing agent is added to the collected agglomerated material to separate the object to be removed and the flocculant, and the separated object to be removed and the flocculant are recovered and recovered respectively. This is achieved by supplying the obtained flocculant to a fluid to be treated containing a new material to be removed while a plurality of materials are mixed.

  In addition, a polymer agent is used as a flocculant to increase the size of the agglomerated material, so that the agglomerated material can be easily separated and recovered, and hydrochloric acid is added to the recovered agglomerated material to break down the bond due to the polymer agent. The flocculant is reused by separating the flocculant from the decomposed flocculant and supplying it to the fluid to be treated.

  According to the present invention, since sludge is decomposed and the flocculant is recovered and reused, there is an effect that the operating cost of the apparatus can be reduced.

  In addition, the polymer agent is increased by using a polymer agent as the aggregating agent, collecting the agglomerated material so that it can be easily separated, and adding a predetermined concentration of hydrochloric acid to the recovered agglomerated material. Thus, the coagulant can be efficiently released, and the coagulant can be efficiently separated and recovered from the decomposed aggregated material, supplied to the fluid to be treated, and the coagulant can be reused.

  The flocculant is added to the fluid to be treated to enlarge the material to be removed (to make the agglomerated material), and the material to be removed is filtered and removed from the fluid to be treated to remove the material to be removed (aggregated material) that is sludge. The decomposition agent is added to decompose the material to be removed and the flocculant without excessive decomposition, and the decomposed flocculant is supplied as it is to a new fluid to be treated.

  An embodiment of the present invention will be described with reference to FIG. FIG. 1 shows a flow of a sludge separation / recovery device combining a magnetic separation / purification device and a sludge recovery device. The raw water 1 having contaminated particles such as oil is preliminarily mixed (not shown) with a coagulant (for example, vanous sulfate, polyaluminum chloride or iron chloride) and magnetic powder, and has a relatively high rotational speed ( The blade was introduced into the agitation tank 3 with a peripheral speed of about 1 m / s to 2 m / s), and then formed with a magnetic micro floc of about several hundred micrometers, while the rotation speed was relatively low (the peripheral speed of the blade was 0). Flowing into the stirring tank 4 and adding the polymer flocculant 2, the magnetic micro flocs form magnetic flocs of the order of several millimeters (the process of forming the magnetic flocs is illustrated). 8). The magnetic floc and pretreatment water generated in this way are introduced into the next tank 5. In the tank 5, a net 6 ′ is formed on the outer peripheral surface of the rotating drum 6. The net 6 ′ is a film having openings of several micrometers to several tens of micrometers, for example, made of stainless steel fine wires or polyester fibers.

  The pretreated water flowing into the tank 5 passes through the net 6 ′ and flows into the rotating drum 6. At this time, the magnetic flocs in the pretreated water are collected by the net 6 ′, and the pretreated water from which the magnetic flocs have been removed by filtration are discharged from the discharge opening in the rotary drum 6 and removed as purified water 17 from the system. It is released.

  On the other hand, the magnetic flocs adhering to the net 6 ′ are washed away from the net 6 ′ by ejecting washing water (not shown) from a nozzle provided inside the rotary drum 6, and then staying near the water surface. The magnetic field generating means 8 built in the rotating body 7 arranged in the vicinity, for example, is attracted to the surface of the rotating body 7 by a superconducting magnet or a permanent magnet, and moves in the direction of the oyster removing plate 9 by the rotation of the rotating body 7. Then, it is peeled off from the surface of the rotating body 7 by the oyster removing plate 9 and naturally falls in the sludge collecting tank 11 and stored.

  The magnetic floc 10 stored to some extent in the sludge recovery tank 11 is transferred to the next sludge decomposition tank 12 and decomposes the polymer flocculant by adding an appropriate amount of hydrochloric acid 13 with stirring, for example, oil, It is decomposed into a flocculant and magnetic powder containing treated water (decomposition process of magnetic floc is shown in FIG. 9). The pH of the hydrochloric acid to be added depends on the state of the magnetic floc 10 but is preferably in the range of 2 to 4. By adding an appropriate amount of hydrochloric acid, the binding of the polymer flocculant is broken and a micro floc state is obtained. Since the micro floc is only stuck by the electric charge of oil or iron chloride, it can be separated by stirring and can be separated. If the concentration of hydrochloric acid is too high, the magnetic powder dissolves in addition to the polymer flocculant, which is inappropriate. The magnetic floc decomposed with an appropriate residence time is further transferred to the settling tank 14.

  Furthermore, in the settling tank 14, by providing an appropriate residence time, oil having a low specific gravity floats above the settling tank 14, and in the lower part thereof is separated into a flocculant containing treated water and a magnetic powder having a high specific gravity. The The mixture 16 of the flocculant and the magnetic powder containing the treated water is returned to the raw water 1 and reused. As the shape of the blade 20, a general paddle blade, a turbine blade, or the like can be used. Reference numeral 21 denotes a pH adjusting agent for adjusting the pH of the mixture 16, for example, caustic soda, and 22 denotes an adjusting means for detecting the pH value of the mixture 16 and adjusting the amount of the pH adjusting agent 21.

  When the raw water is seawater or the like containing crude oil, the oil 15 that is sludge particles is recovered, and the mixture 16 of the flocculant and magnetic powder containing seawater is returned to the raw water 1 and reused. Thereby, by applying it to the accompanying water treatment of the oil field, it is possible to purify seawater, recover oil, reduce consumption of coagulant and magnetic powder.

  As described above, according to this embodiment, the magnetic floc can be decomposed with hydrochloric acid and separated by sedimentation, and the flocculant and the magnetic powder can be recovered and reused, so that the operating cost of the apparatus can be reduced. There is. Furthermore, when the raw water contains valuable crude oil, the amount of recovered crude oil can be increased.

  In addition, according to the present embodiment, the sludge recovery tank 11, the sludge decomposition tank 12, and the settling tank 14 are arranged and combined in the direction of gravity, so that the treated water flows in the direction of gravity and requires little power consumption. Recovery of the flocculant and magnetic powder can be realized.

  In addition, although the present Example demonstrated the case of the treated water containing oil as an example, to-be-removed thing is applicable also to things other than oil.

  FIG. 2 shows another embodiment of the present invention. The sedimentation tank 14 is provided with, for example, a differential pressure type liquid level gauge 32. When the liquid level is higher than the set value, the signal 33 is pumped via an appropriate controller (not shown). The automatic valve 31 provided at the outlet of 30 is opened to keep the liquid level constant. When the liquid level is lower than the set value, the reverse operation is performed.

  According to the present embodiment, since the liquid level of the precipitation tank 14 can be kept constant, even if the processing amount of the magnetic floc 40 decomposed by hydrochloric acid fluctuates, the state of sedimentation separation in the precipitation tank 14 is disturbed. Since the flocculant and the magnetic powder can be recovered and reused, the operation cost of the apparatus can be reduced.

  FIG. 3 shows another embodiment of the present invention. Two sets of perforated plates 42 and 43 are provided in the upper part of the sedimentation tank 14, and a stirring blade 41 is disposed in the lower part in the vicinity of the tank bottom. The magnetic floc 40 decomposed by hydrochloric acid flows down to the upper part of the settling tank 14, and the first perforated plate 42 reduces the kinetic energy of the velocity component in the vertical direction. Further, the vertical kinetic energy is reduced by the second perforated plate 43. Thereby, the separation state of the flocculant and the magnetic powder containing the oil and the treated water separated by specific gravity is not so much affected. On the other hand, in the lower part of the precipitation tank, the stirring blade 41 rotates at a low speed, that is, rotates at a speed that does not disturb the oil layer separated by specific gravity, and the flocculant and the magnetic powder are well mixed. In the present embodiment, a perforated plate is shown as a means for reducing kinetic energy, but an appropriate wire mesh or the like may be used.

  According to the present embodiment, the flocculant and magnetic powder having a more uniform concentration can be recovered and reused, so that the performance of the magnetic separation and purification device can be stabilized, and the operation cost of the device can be reduced. is there. Moreover, since the treated water containing the flocculant and the magnetic powder is stirred by the stirring blade 41, it is possible to prevent the supply line from being clogged with the flocculant and the magnetic powder.

  FIG. 4 shows another embodiment of the present invention. Four baffle plates 50 to 54 are arranged in a staggered pattern in the upper part of the settling tank 14 in the vertical direction of the tank. The magnetic floc 40 decomposed by hydrochloric acid flows down to the upper part of the settling tank 14, reduces the kinetic energy of the velocity component in the vertical direction by the first baffle plate 50, and moves in the horizontal direction along the first baffle plate 50. Converted to flow. Next, the flow is reversed at the inner wall of the settling tank, and a flow along the second baffle plate 51 is generated. The inside of the sedimentation tank 14 flows down through the third baffle plate 52 and the fourth baffle plate 53 while generating such a flow. Thereby, the flow of the vertical direction of the sedimentation tank 14 reduces, and it does not have much influence on the separation state of the flocculant and the magnetic powder containing the oil and the treated water separated by specific gravity.

  According to this embodiment, the flocculant and the magnetic powder can be recovered and reused without disturbing the state of sedimentation separation in the sedimentation tank 14, so that the operation cost of the apparatus can be reduced.

  FIG. 5 shows another embodiment of the present invention. In this figure, the same reference numerals as those in FIG. This figure is different from FIG. 1 in that the tank 3, the tank 4, and the tank 5 are made into independent layers. The oil-containing waste liquid discharged from the oil field is put into the raw water tank 100, and the pH adjuster 61 is added to adjust the pH value to an optimum value. In this case, iron chloride (ferric chloride) is supplied into the tank 3 to prevent acidity, and the tank 3 is adjusted in advance so as to be almost neutral. Here, the pH adjusting agent 61 is supplied to the raw water tank 100, but may be adjusted in the tank 3 or before entering the tank 3. Here, 62 is magnetic powder, and 63 is ferric chloride which is a flocculant. Reference numeral 70 denotes an oil recovery device that recovers oil floating on the upper portion of the settling tank 14. Reference numeral 64 denotes a flocculant solution containing magnetic powder whose acidity is increased by addition of hydrochloric acid 13, in this case, a pH adjuster for adjusting the pH value of the aqueous iron chloride solution to a predetermined value, in this case, caustic soda.

  According to the present embodiment, since the tanks 3, 4, and 5 are independent of each other, it is easy to set conditions optimal for processing.

  FIG. 6 shows another embodiment of the present invention. In this figure, the same reference numerals as those in FIGS. 1 and 5 denote the same members, and a description thereof will be omitted. This figure is different from FIG. 5 in that the magnetic powder 62 is not supplied. In the tank 4, flocs that are aggregated substances having no magnetic powder are formed and supplied to the tank 5 a. In the tank 5a, for example, the floc accumulated in the tank 5a by rotating a spiral net is scooped up from the treated water by the flock recovery machine 7a and stored in the sludge recovery tank 11. An aqueous solution of iron chloride as a flocculant is recovered from the settling tank 14 and reused.

  According to this embodiment, oil can be recovered without using magnetic powder, and the flocculant can be reused.

  FIG. 7 shows another embodiment of the present invention. In this figure, the same reference numerals as those in FIGS. 1 and 5 denote the same members, and a description thereof will be omitted. This figure is different from FIG. 5 in that a plurality of tanks 5, in this case two, are provided and the treated water having magnetic flocs is separated by two filters.

  According to the present embodiment, the separation apparatus can be prevented from being enlarged, and the sludge separation and recovery apparatus can be configured in accordance with the processing capacity.

  It is suitable for removing unnecessary substances in liquids such as water purification of rivers and lakes, associated water treatment of oil fields, ballast treatment of tankers, and can be applied to the recovery and reuse of flocculants used for removing unnecessary substances.

It is the schematic which shows the sludge separation-and-recovery apparatus which is one Example of this invention. It is a block diagram which shows other implementation of the sedimentation tank of FIG. It is a block diagram which shows other implementation of the sedimentation tank of FIG. It is a block diagram which shows other implementation of the sedimentation tank of FIG. It is the schematic which shows the sludge separation-and-recovery apparatus which is the other Example of this invention. It is the schematic which shows the sludge separation-and-recovery apparatus which is the other Example of this invention. It is the schematic which shows the sludge separation-and-recovery apparatus which is the other Example of this invention. It is a figure which shows the formation process of a magnetic floc. It is a figure which shows the decomposition | disassembly process of a magnetic floc.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Raw water, 2 ... Polymer flocculant, 6 ... Rotary drum, 6 '... Net, 7 ... Rotating body, 8 ... Magnetic field generating means, 9 ... Oyster removing plate, 10 ... Magnetic flock, 11 ... Sludge collection tank, 12 ... sludge decomposition tank,
DESCRIPTION OF SYMBOLS 13 ... Hydrochloric acid, 14 ... Precipitation tank, 20 ... Wing | blade, 32 ... Level gauge, 41 ... Stirring blade, 42 ... 1st perforated plate, 50 ... 1st baffle plate.

Claims (12)

  A flocculant made of a plurality of materials is supplied to a fluid to be treated containing the material to be removed, and the material to be removed is agglomerated to a predetermined size by the flocculant to form an agglomerated material. The aggregated material is separated and recovered, a decomposition agent is added to the recovered aggregated material to separate the object to be removed and the flocculant, and the separated object to be removed and the flocculant are separated from each other. And removing the recovered flocculant into a fluid to be treated containing a new material to be removed while mixing a plurality of materials.   A magnetic substance and an aggregating agent are supplied to a fluid to be treated containing a substance to be removed, and the agglomerated substance is formed by aggregating the magnetic substance together with the substance to be removed by the aggregating agent. Separating and recovering, adding a decomposing agent to the recovered aggregated material to separate the object to be removed, the magnetic body and the flocculant, and recovering the separated object to be removed and separating A method for removing an object to be removed from a fluid, wherein the magnetic substance and the flocculant are combined and supplied to a treatment fluid containing a new object to be removed.   3. The method for removing an object to be removed from a fluid according to claim 1, wherein the flocculant contains a polymer agent and hydrochloric acid is used as the decomposing agent.   Means for supplying a flocculant to the fluid to be treated containing the object to be removed, and an agglomerated substance forming tank for aggregating the object to be removed to a predetermined size by the supplied flocculant to form an agglomerated substance, Separating means for separating and collecting the aggregated substance from the fluid to be treated containing the aggregated substance, means for supplying a decomposing agent to the separated and collected aggregated substance, A separation tank that separates the flocculant from each other, a collection unit that collects the separated object to be removed and the flocculant, respectively, and a collected object that contains the collected flocculant as a new object to be removed. An apparatus for removing an object to be removed from a fluid, comprising supply means for supplying the treatment fluid.   Means for supplying a magnetic substance and a flocculant to a fluid to be treated containing a substance to be removed, and an agglomerated substance forming tank for aggregating the magnetic substance together with the substance to be removed by the supplied flocculant to form an agglomerated substance Separating means for separating and collecting the aggregated substance from the fluid to be treated containing the aggregated substance, means for supplying a decomposition agent to the separated and collected aggregated substance, and adding the decomposition agent to the aggregated substance A separation tank for separating the object to be removed, the magnetic body, and the flocculant, a recovery means for recovering the separated object to be removed, the magnetic body, and the flocculant, the recovered magnetic body, and An apparatus for removing an object to be removed from a fluid, comprising supply means for supplying a flocculant together to a fluid to be treated containing a new object to be removed.   Agglomerate generating means for continuously supplying a magnetic substance and an aggregating agent to a fluid to be treated containing the object to be removed, and aggregating the object to be removed with the magnetic substance and the aggregating agent to form an aggregated substance by stirring; Filtration means for filtering the fluid to be treated having an opening through which the aggregated substance cannot pass, magnetic field generating means for magnetically attracting the aggregated substance collected by the filtration means, and the magnetically attracted In a magnetic separation and purification apparatus provided with a sludge collecting means for collecting the agglomerated material and a oyster removing means for removing the agglomerated material in the sludge collecting means, the agglomerated material stored by the oyster removing means A tank in which hydrochloric acid is added and stirred, a settling tank for separating the agglomerated material decomposed by the hydrochloric acid in the tank into a magnetic substance, a coagulant and a material to be removed, and a magnetic substance separated by the settling tank. Yo Sludge separation and recovery apparatus characterized by and a flocculant is recovered together provided a supply means for adding to the treated fluid.   The sludge separation and recovery apparatus according to claim 6, wherein a liquid level gauge is provided in the settling tank to control the liquid level to be constant.   7. The sludge separation and recovery apparatus according to claim 6, wherein at least one perforated plate is provided above the settling tank.   The sludge separation and recovery apparatus according to claim 6, wherein at least one baffle plate is provided on the upper part of the settling tank.   10. The sludge separation and recovery device according to claim 8, wherein a sludge separation and recovery device comprises a stirring blade at a lower portion of the settling tank.   The sludge separation and recovery apparatus according to claim 6, wherein the sludge separation and recovery apparatus performs pH adjustment by measuring the pH of the magnetic substance and the flocculant separated by the settling tank. The sludge separation and recovery apparatus according to claim 6, wherein the flocculant contains a polymer agent and hydrochloric acid is used as the decomposition agent.

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