JPH04108193A - Nozzle for supplying water suspension - Google Patents

Abstract

PURPOSE:To homogeneously suspend an aqueous suspension in the transverse direction from a nozzle by applying a specific force to the aqueous suspension in a passage between a magnet disposed in the passage and electrodes disposed in a wall member. CONSTITUTION:A pair of electrodes 6 are disposed at positions nipping the magnetic field of a wall member 300Z to flow an electric current so as to intersect with the magnetic field caused by magnets disposed in a passage 3, and an electric voltage is applied to the electrodes. An electric current flows in the passage of a nozzle so as to intersect with the magnetic field, and a force orthogonal to the direction of the electric current and to the direction of the magnetic field, respectively, is generated in the water suspension flowing in the passage.

Description

[Detailed description of the invention]

[0001]

[Industrial application field]

The present invention relates to a novel configuration of a head box nozzle for a paper machine and a liquid supply nozzle for a coating machine. From the outlet at the tip of the head box nozzle of the paper machine, paper material in the form of an aqueous suspension is continuously supplied in the form of a thin film onto a moving supporting band, such as a fourdrinier belt. Also, from the outlet at the tip of the liquid supply nozzle of the coating machine, the coating material, which is an aqueous suspension, is continuously supplied in the form of a thin film onto the paper web or the like that is the supporting band that is being transferred. These nozzles have at least one slit-like rectangular cross-section channel, the channel having a pair of opposing wide walls defining a thickness of the channel;
The flow path is defined by a wall member comprising a pair of opposing narrow walls that define the width of the flow path. [0002] The present invention relates to a nozzle having such a basic configuration and used in the paper manufacturing industry and the coating industry. [0003] Examples of the aqueous suspension to be used by the aqueous suspension supply nozzle according to the present invention include various organic pulp paper materials such as wood pulp, linter pulp, and synthetic pulp, glass fibers, carbon fibers, metal fibers, Various inorganic pulp paper materials such as ceramic fibers, various filled paper materials such as calcium carbonate fine particles, clay, etc. 1
．． There are products in which various paper materials or coating materials such as pigments, various coating material sizing agents such as microcapsules, and dyes are suspended in water and adjusted to a substantially uniform concentration. [0004] Further, examples of the transition support band to be used in the aqueous suspension supply nozzle according to the present invention include, for example, a circular mesh belt that is rotatingly transitioning at the nozzle exit of a head box for a paper machine, and a horizontally transitioning belt. There are fourdrinier belts, twin net belts that move together, or coated paper webs, film webs, etc. that move at high speed at the nozzle outlet of the liquid supply head for coating machines. [0005]

[Prior Art] The water suspension passing through the nozzle as described above can be supplied onto the supporting band in a uniform suspended state in the width direction in order to achieve uniform paper forming or uniform coating. desired. In order to achieve such a uniform suspended state, it is necessary to uniformly disperse suspended substances in the flow path. [0006] In addition, the flow velocity distribution in the width direction of the flow in the flow channel becomes uneven due to the resistance caused by the narrow walls. It is necessary to correct the flow velocity near the width wall to bring the overall flow velocity distribution close to uniform. [0007]Furthermore, such non-uniform flow velocity distribution occurs not only in the vicinity of the narrow wall but also in the intermediate region in the width direction. Nowadays, paper making and coating are carried out at high speeds, so uneven flow velocity in the middle region in the width direction, which was not a problem in the past, has a negative impact on the product, so it is necessary to correct this. Must. [0008] Even in the case of uniformly dispersing the water suspension and in the case of making the flow velocity distribution uniform in the width direction, it is necessary to apply additional force to the water suspension in the flow path. There is. [0009] In conventional paper machine head box nozzles, one method for dispersing an aqueous suspension is to taper the flow path to generate acceleration in the flow. There were some that perturbed the flow due to velocity gradients (shear forces). In addition, as another method, a perforated rotating cylinder (evener roll) or a convex-concave member is provided in the flow path, and the water suspension is dispersed by the force of physical collision. However, in these methods, the dispersion means is fixed, so dispersion in a selected region in the width direction can be promoted or suppressed at any time, or the strength of the force applied to the aqueous suspension can be adjusted as desired. I can't do the dispersion. [0010] In addition, in order to make the flow velocity distribution uniform in the width direction, a method that is used in both the head box nozzle of a paper machine and the coating material supply nozzle of a coating machine is to use an outlet at the tip of the nozzle. A flexible lip is provided, a plurality of mechanical pressing means are arranged close to each other along the width direction of the lip, and the degree of opening of the lip is adjusted by selectively operating the individual pressing means. There are known methods that can cause local changes. However, with such a method that utilizes local deformation of the lip, problems such as hysteresis and permanent deformation of the lip cannot be ignored, and deformation of the lip in a local area also affects adjacent areas. It was not possible to make fine adjustments accurately. [0011] As mentioned above, in recent years, paper making and coating have become faster, and more precise fine adjustment has become necessary than ever before. [0012] As described above, in various conventional devices, efforts have been made to make the aqueous suspension into a somewhat uniform suspension state in the width direction of the flow, but they are lacking in controllability and strictness. This method is insufficient, and is not satisfactory especially in recent years when paper making and coating speeds have increased. [0013]

[Problem to be solved by the invention]

Therefore, an object of the present invention is to enable dispersion in a selected area in the width direction to be promoted or suppressed to a desired degree, and also to finely adjust the flow velocity distribution in the width direction, so that dispersion from a nozzle The objective is to make the aqueous suspension into a uniform suspension state in the width direction, and to prevent non-uniformity in the width direction from occurring in products processed at high speed. [0014]

[Means to solve the problem]

According to the present invention, there is provided a nozzle for continuously supplying a water suspension in a thin film form from a distal end outlet onto a transitional support band, the nozzle having at least one slit-like flow path having a rectangular cross section. a nozzle in which the flow path is defined by a wall member consisting of a pair of opposing wide walls defining a thickness of the flow path and a pair of opposing narrow walls defining a width of the flow path; A magnet arranged in the flow path to generate a magnetic field in the longitudinal direction of the flow path, and a pair of magnets arranged on the wall member at positions sandwiching the magnetic field to cause a current to flow so as to cross the magnetic field. and an electrode arranged in such a manner that a force perpendicular to each of the direction of the current and the direction of the magnetic field can be generated in the water suspension flowing in the flow path.
A nozzle for dispensing a water suspension is provided. [0015]

[Effect]

In the nozzle according to the invention, a magnet generates a magnetic field in the nozzle flow path in the longitudinal direction of the flow path. On the other hand, by applying a voltage between electrodes arranged in pairs at positions on both sides of the magnetic field of the wall member, a current flows in the nozzle flow path so as to cross the magnetic field. As a result, a force in the direction of Fleming's left thumb, which is orthogonal to the direction of the current and the direction of the magnetic field, is generated in the water suspension flowing in the flow path. [0016] In determining the specific arrangement of the magnets and electrodes in the nozzle of the present invention, first, the direction of the force to be generated in the aqueous suspension is selected. Based on the direction of this generated force, the arrangement of the electrodes and magnets is selected from among various aspects,
It is determined. [0017]Although the electrodes may be arranged only at positions in the channel width direction where dispersion of the aqueous suspension or adjustment of the flow rate is required, it is also possible to arrange multiple pairs of electrodes along the width direction. However, these may be used selectively as necessary. For example, in paper-made products or coated products, if unevenness in physical properties occurs in the width direction due to uneven basis weight distribution in the width direction, unevenness in the amount of coating film deposited in the width direction, or poor formation, the location of the occurrence of these unevenness may occur. A current is passed between the selected electrode pair corresponding to the current. [0018] In the present invention, in which the magnet is arranged to generate a magnetic field in the longitudinal direction of the nozzle flow path, current flows in the width direction or thickness direction of the nozzle flow path. As a result, an electromagnetic force perpendicular to the current direction and the magnetic field direction is generated in the water suspension at the selected width direction position, and the electromagnetic force accelerates, decelerates, deflects or vibrates the water suspension. By doing so, the non-uniform suspension state of the aqueous suspension, which was the cause of unevenness on the product, is corrected. [0019] As the magnet, an electromagnet whose magnetic field strength can be adjusted can be used. It is also possible to change the magnitude of the current flowing between the electrodes. [0020] By changing the magnitude of the current and the strength of the magnetic field in this way, the magnitude of the electromagnetic force can be changed. Therefore, the magnitude of the current and the strength of the magnetic field are adjusted depending on how much dispersion is performed and how much the flow is accelerated or decelerated. [0021] By reversing the direction of the current or magnetic field, the force generated on the aqueous suspension can be reversed. For this purpose, alternating current may be used to successively change the direction of electromagnetic force. [0022]

【Example】

An embodiment of the aqueous suspension supply nozzle according to the present invention, indicated by reference numeral 1 in FIG. , a backup roll that rotates in the direction shown by arrow A in Fig. 1 with a substantially uniform flow velocity distribution in the width direction (indicated by arrow X in Fig. 1, hereinafter referred to as the X direction) while leveling it into a thin film. In order to continuously supply the paper over the outer supported surface (coated surface) 22 of the base paper support band 2, which is engaged with the base paper supporting band 2 and moves in an arc shape together with its outer peripheral surface at a speed of about 1500 m/min. , thickness direction (indicated by arrow Z in Figure 1, hereinafter referred to as the X direction)
It is surrounded on all sides by outer walls 3Z and 3X facing each other in the X direction, and has an equal width of approximately 8 m in the elongated direction (indicated by arrow Y in Figure 1, hereinafter referred to as
It is called the Y direction. ), with an equal thickness of 8 mm, and the outlet 30 at the tip is brought close to the supported surface 22 of the support band 2.
A thin and wide channel 3 is formed which has a slit-like opening in the direction, and is surrounded by outer walls 3Z and 3X.
A flow path portion 4 is formed with a substantially rectangular cross section (shown along the line CC in FIG. 1) extending 25 cm in length substantially parallel to the Y force direction. [0023] This water suspension supply nozzle 1 has a structure that surrounds the insulated flow path portion 4H in order to electrically insulate the flow path portion extending over the entire width of the flow path 3 in the X direction over a total length of 20 cm. The liquid contact parts 300Z and 300X of the outer wall parts 30Z and 30X are made of a wear-resistant non-conductive material made of alumina porcelain thin plate (thickness 0
．． In order to form a magnetic field H approximately parallel to the Y direction as shown by the arrow H in FIG. The outer wall portions 30Z and 30X surrounding the road portion 4H are made of stainless steel and non-magnetic material, and a high vacuum chamber 544 containing laminated heat insulating material (not shown) is formed inside. G is immersed in the cooling liquid LN2 surrounded by the wall 540 and injected through the liquid supply insulated pipe, and is emanating from the cooling liquid LN2.
A heat insulated container 54 is formed in which N2 is exhausted and recovered via a degassing and recovery insulated pipe, and then compressed and liquefied again and circulated to keep it at a critical temperature below 77. A multi-core wire 520 made of an oxide-based ceramic ultra-thin film superconducting thin wire is connected to the magnetic field forming channel portion 4.
0H is wound in a direction substantially perpendicular to the Y direction and is brought close to the channel portion 40H via the liquid contact wall portions 300Z and 300X, and the superconducting coil 52 and the permanent current excited by the DC intermittent excitation power source 56. A superconducting magnet 5 composed of a cryostat consisting of a switch (not shown) is provided, and a wear-resistant non-magnetic material ( Thickness 0.
A pair of electrode pairs 6 made of multipolar electrodes each having a plurality of rectangular planar electrode surfaces 620 with a width of 8 m and a length of 7 cm formed by stringing together single electrode surfaces 600 (2 mm) in a strip shape spaced apart from each other by 5 mm. A plurality of electrode surfaces 620 are exposed on the liquid contact wall portions 400Z facing each other in the Z direction that concave the flow path portion 40H, each extending over the entire width in the X direction, and are arranged facing each other in parallel at a distance of 8 mm in the Z direction, Liquid C flowing through the flow path portion 40H
On the other hand, for each facing single electrode surface 600 of the electrode pair 6, in FIG. After the detected pulse is smoothed by the current detector 700, it is compared with the set current value from the current setting device 702, and based on the difference signal value, it is automatically adjusted by the servo motor 706 which is amplified and supplied with power via the servo drive circuit 704. The current value can be adjusted by the variable resistor 70. 708 is a diode.)
(includes a pulse output power source 76 whose frequency can be set variable. In FIG. 1, the other opposing electrode pairs 6
Although the current regulating device connected to the single electrode surface 600 is not shown, it is the same as the current regulating device 7. ) attached,
The flow rate and shaking state of the coating material aqueous suspension C are adjusted locally or throughout the flow path portion 40H so that the liquid can be continuously supplied to the coating material supported surface 22 of the support band 2. . [0024] In the aqueous suspension supply nozzle of the present invention, the length of the magnetic field forming flow path portion must not be longer than the length of the insulated flow path portion, and the length of the magnetic field forming flow path portion must not exceed the length of the insulated flow path portion. The portions are respectively formed within the insulated channel portion. [0025] The electrode pair is composed of a unipolar electrode or a multipolar electrode, or a unipolar electrode and a multipolar electrode. In order to partially adjust the flow state of an aqueous suspension such as a paper material, it is necessary to expose the electrode surface over the entire width of the channel, which includes at least one multipolar electrode in the electrode pair, to cover the entire width of the channel. Either a magnetic field forming channel portion is formed, or a plurality of magnetic field forming channel portions are formed, each having a monopolar electrode arranged in parallel in the longitudinal direction over the entire width of the channel. is preferable. [0026] The electrode surface is integrally formed in the same plane as the liquid contact wall surface of the insulated liquid contact wall portion so as not to form an uneven surface such as a gap or a step, or it may protrude from or fall above the liquid contact wall surface. It may have any shape, such as being recessed into the liquid contacting wall portion and integrally formed in a convex or concave shape. However, while reducing the shear stress received from the liquid contact wall surface and flattening the flow velocity distribution in the thickness direction of the liquid flow, stagnation is formed in the flow path portion and dirt such as the slime is deposited there. It is preferable that it is formed into a flat shape so that it does not peel off and get mixed into the liquid flow. [0027] In addition, each liquid flow portion near both edges in the width direction of the flow path receives resistance from the liquid contact surface of the opposing outer wall, especially in the thickness direction, and shearing stress is generated, resulting in a turbulent flow state, resulting in unstable flow. Therefore, a magnetic field forming flow path portion must be formed over at least a predetermined width of both edges in the width direction of the flow path so that the unstable flow state can be corrected. [0028] As the current regulating device, direct current, alternating current (single phase or polyphase)
It may output any waveform such as pulsating flow or pulse, but for liquid flow that can be sufficiently adjusted only by accelerating, decelerating, and deflecting the liquid flow, a device that can output direct current, accelerating, decelerating,
For liquid flows that require vibration operations in addition to deflection, it must be possible to output the above-mentioned alternating current, pulsating flow, and pulses. [0029] The current regulating device includes a current value regulating device having a well-known configuration such as a variable resistor for continuously increasing and decreasing the output current value, or a tapped transformer for increasing and decreasing the output current value in steps. You must have the means. Further, an on/off means such as a switch must be provided for selectively applying a desired value of current adjusted by the current value adjusting means to each single electrode surface of each electrode of the electrode pair. Sometimes, when exciting the liquid flow (including the above-mentioned shaking), it is preferable that the current adjustment device is equipped with an output frequency and/or waveform adjustment means such as a thyrisk inverter. Various types of frequency and/or waveform adjustment means are known. [00301 Any electrode surface arrangement is acceptable as long as it is 00301]. [0031] It is done. [0032] [0033] When a reaction occurs, bubbles and harmful substances are generated, and the bubbles and the like adhere to paper materials, etc., thereby impairing product quality. [0034] Therefore, in order to prevent this electrolytic reaction from occurring, it is preferable to use an alternating current excitation electromagnet and to apply an alternating current synchronized with the phase of the excitation alternating current to the electrode pair. That is, the operation of speeding up, decelerating, or deflecting the magnetic field-forming current-carrying liquid flow portion can be performed using a current that is synchronized so as to be out of phase by approximately O or π with respect to the excitation alternating current, and the excitation Operations can also be performed at the same time. In this case, a phase difference adjusting means must be provided. Various types of phase difference adjustment devices are known. [0035] The non-magnetized inner and outer wall portions are preferably formed of stainless steel and non-ferrous steel. Various types of non-magnetized wall materials are known, such as strong fiber-reinforced plastic wall materials and ceramic wall materials. [0036] Furthermore, at least the liquid-contact wall portions of the inner and outer walls forming the insulated flow path portion are made of non-conductive materials such as various synthetic rubber sheet covering materials, various synthetic resin sheet covering materials, ceramic film covering materials, etc. Of course, both the inner and outer walls may be made of the non-conductive material. [0037] At least the electrode surface portion of the monopolar electrode and the multipolar electrode of the electrode pair is formed of an electrolytic corrosion-resistant and wear-resistant material such as stainless steel, chromium-plated metal, hard carbon, lead, titanium, tantalum, or platinum. The electrode core material is preferably made of a low electrical resistance material such as copper or aluminum. Various electrode materials are known [0038] In particular, as the electromagnet used in the aqueous suspension supply nozzle of the present invention, ultrafine multifilamentary wires made of niobium-titanium alloy, yttrium-barium-copper-oxygen ceramics, etc. It is preferable that a wire ring formed by winding a superconducting core wire such as a thin strip-shaped core wire to form a hollow magnetic core with a rectangular cross section is housed, and is equipped with an insulated vacuum container in which a refrigerant such as liquid elyram or liquid nitrogen is injected. , various embodiments of superconducting electromagnets are known. [0039] Since a superconducting electromagnet can usually obtain a magnetic flux density of 17 Te or less, it can be arranged so that only one of the air-core magnetic pole surfaces is close to the flow path portion. [0040] The shorter the distance between the electrode surfaces and the higher the liquid electrical conductivity, the higher the current density increases in proportion to the distance and the conductivity. Therefore, it is necessary to provide a pair of electrodes with electrode surfaces facing each other in the thickness direction, or use a material such as a paper material with high electrical conductivity that does not have a negative effect on product quality, for example, a conductivity enhancer such as sulfuric acid. A suspension may also be used. [0041] Normally, in fourdrinier paper machines, double net paper machines, etc., and coating machines such as Fantine blade coaters and Joto dwell coaters, a liquid supply pump called a fan pump or the like is used to supply a water suspension to the nozzle. Aqueous suspensions of paper materials, etc. are fed under pressure. At this time, as the liquid is stirred by the rotary blades in the pump, pulsations of several tens of H2 or more and mainly at a specific frequency are propagated into the liquid. [0042] Further, a screen is used to classify and remove impurities such as pieces of wood bark and pieces of stone masonry that have been suspended in the liquid in advance. A rotary scraper or the like is usually rotating inside the screen, and as the liquid is stirred, pulsations of a specific frequency are mainly propagated into the liquid. Therefore, in order to dampen these pulsations, a pulsation damping device such as a pneumatic damper called an attenuator is usually installed in the water suspension supply nozzle and the main pipe for feeding liquid between the nozzle and the pump or screen. is set up. However, with this type of device, it is not possible to intensively and selectively attenuate only the pulsation components of specific frequencies, and undamped pulsation causes wavy basis weight unevenness and wavy coating film adhesion in the longitudinal direction of the product and across the width. Form unevenness. [0043] In addition, in order to transfer a transfer support such as a paper web band or a paper base material band at a predetermined speed, the support band is engaged with a rotating roll driven by a gear electric motor, and the support band is engaged with a rotating roll driven by a gear electric motor, and The pulsation derived from backlash etc. causes the rotation of the roll to pulsate, and the pulsation forms wavy basis weight unevenness and wavy coating film deposition unevenness in the width direction in the longitudinal direction of the product. These wavy irregularities have been a quality problem, especially in products called ultra-light paper, slightly coated paper, etc., and high-grade printing sheet products. [0044] Now, it has been found that these pulsations can be removed by the aqueous suspension supply nozzle of the present invention. That is, the aqueous suspension supply nozzle of the present invention is called a β-gauge or the like because it can induce waves of a specific frequency in a specific direction and across the width in an aqueous suspension such as paper material. For standing wave components across the width of longitudinal direction basis weight fluctuations detected online by basis weight sensors and coating film adhesion sensors, and output by frequency spectrum analysis calculations of external detection signals by microprocessors. , by inducing a standing wave electromagnetic force to cancel out these fluctuations, it is possible to almost completely cancel out the fluctuations. It can also function as the attenuator. [0045]

【Effect of the invention】

According to the aqueous suspension supply nozzle of the present invention, the dispersion state and flow rate in the width direction of the paper material or coating material aqueous suspension that is continuously supplied onto the transition support band such as a paper screen or a substrate to be coated The distribution value can be finely adjusted by accelerating, decelerating, deflecting, and vibrating the liquid due to electromagnetic force generated in the liquid. [0046] Moreover, the fine adjustment can be carried out in a limited manner with almost no effect on the surrounding unadjusted liquid flow portion. [0047] The finely adjustable width is determined by the distance between the centers of the opposite electrode surfaces in the width direction of the electrode pair, or the distance in the width direction between the centers of adjacent single electrode surfaces of the multipolar electrode, and the distance Since the width can be reduced to a minimum of several millimeters, local fine adjustment over a width of several millimeters is possible. [0048] Furthermore, since the nozzle of the present invention does not require any uneven member in the flow path as described above, it is free from inconveniences such as increased resistance from the liquid-contacted wall surface and adhesion and peeling of dirt such as slime. does not occur at all. [0049]Furthermore, the nozzle of the present invention does not indirectly vibrate or disturb the liquid using a perforated rotating cylinder or the like as described above, but instead vibrates and disturbs the liquid itself by electromagnetic force induced therein. Therefore, the vibration disturbance is carried out extremely efficiently and uniformly. The frequency of the vibration can be set arbitrarily within the range from several Hz to several KHz, and the amplitude can also be finely adjusted, so the vibration can be adjusted according to the particle size and shape of the solid fine particles in the paper material or coating material. By freely finely adjusting the number, amplitude, or direction of electromagnetic force, it is possible to cause the particles suspended in the liquid to resonate or to align them in a desired direction. [00501 Even if the paper material is a highly concentrated aqueous suspension, the paper material can be uniformly dispersed or oriented in a desired direction by strong electromagnetic force. [0051] Furthermore, harmful pulsations of several Hz or more propagated through the liquid caused by the vibrations of the liquid supply pump, drive gear train, etc., as described above, can be prevented.
It is also possible to selectively and effectively attenuate pulsation without a pulsation damping device such as the attenuator. [0052] In the nozzle of the present invention, a strong magnetic field of around ITe or higher can be formed in the liquid flow, and the distance between the opposing electrode surfaces of the electrode pair can be shortened to a few millimeters, so it is possible to Even if the current value passed through the suspension is on the order of several hundred mA, a strong electromagnetic force is induced, and even if the current is direct current,
Changes in water quality due to electric field reactions are extremely small [0053] In addition, an oscillating electromagnetic force is induced near the liquid-contacted wall that forms the concave flow path to destroy the boundary layer near the wall and reduce flow resistance as much as possible. You can also do that. [0054] As described in detail above, the aqueous suspension supply nozzle of the present invention, despite its extremely simple configuration, can produce a wide distribution of paper or coating material in the width direction, Since the orientation in a desired direction can be adjusted, high-quality paper products and coated products with good texture can be manufactured even in high-speed processing.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of a water suspension supply nozzle according to the present invention, (A) is a longitudinal cross-sectional view, and (B) is a C in (A).
-C line sectional view.

[Explanation of symbols]

1: Nozzle, 2: Support band, 22: Supported surface such as paper material, 3: Channel, 3X, 3Z: Outer wall, 30X, 3
0Z: Outer wall part, 300X, 300Z: Wetted part (wall), 30: Tip outlet, 4: Flow path [flow path], 4
00Z: Liquid contact (wall) part, 4H: Insulated flow path part,
40H: Magnetic field forming channel part [channel], 5: Electromagnet, 50: Magnetic core, 52: Wire ring, 6: Electrode pair, 6
00: Single electrode surface, 62: Multipolar electrode, 620:
Multiple electrode surfaces, 7: Current adjustment device, X: (channel) width direction, Y: (channel) longitudinal direction, Z: (channel) thickness direction, C: coating material water suspension, H: magnetic field , ■: Lightning current
F: Electromagnetic force, A: Orthodontic band transition direction.

【Document name】

drawing

Claims (1)

[Claims] 1. A nozzle for continuously supplying a water suspension in a thin film form from a distal end outlet onto a transitional supporting band, the nozzle having at least one slit-shaped channel having a rectangular cross section. and the flow path is defined by a wall member consisting of a pair of opposing wide walls defining the thickness of the flow path and a pair of opposing narrow walls defining the width of the flow path. , a magnet arranged in the flow path to generate a magnetic field in the longitudinal direction of the flow path, and a pair of magnets arranged on the wall member at positions sandwiching the magnetic field so as to cause a current to flow so as to cross the magnetic field. an aqueous suspension, characterized in that the aqueous suspension is equipped with an electrode arranged in the flow path, and is capable of generating a force orthogonal to each of the direction of the current and the direction of the magnetic field in the aqueous suspension flowing in the flow path. Supply nozzle.