JPH0116524B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an ultrasonic filter, and further relates to another method for removing solid foreign matter from slurry using this filter. It is generally known that it is very difficult to separate a slurry containing cohesive fine particles, and no effective method has yet been found. For example, carbon black is a highly cohesive substance in water and aqueous solutions, and the apparent particle size after agglomeration ranges from several 100 μm to several mm. When attempting to remove solid foreign matter (hereinafter referred to as "foreign matter") mixed in carbon black water slurry (hereinafter referred to as "carbon slurry"), if the opening of the material is smaller than the particle size of carbon black after agglomeration, the material may Carbon black, which is originally intended to pass through the material layer, is captured on the surface. For this reason, with the currently commonly used filtration methods such as vibration methods and pressurization methods, it is difficult to remove from the slurry foreign matter that is smaller than the particle size after carbon black agglomeration among the foreign matter mixed in the slurry liquid. Very difficult. The inventor has discovered that the elementary particles of carbon black are 1 μm in size.
Focusing on the following, it was discovered that if the dispersion operation and over-operation of carbon black were performed at the same time, only foreign matter larger than the opening of the material could be captured in the material from the carbon slurry. In other words, by applying ultrasonic waves to the carbon slurry that passes or accumulates between the material and the ultrasonic oscillation surface using an ultrasonic oscillation chip that has an ultrasonic oscillation surface that is parallel or close to parallel to the material, the carbon slurry can be The carbon black agglomerated particles inside are dispersed down to particles smaller than the opening of the material,
The carbon black is passed along with the liquid, and only foreign matter that is larger than the opening of the material contained in the carbon slurry is captured by the material. However, although such alternative methods can be used in the laboratory, there are still problems to be solved in terms of equipment scale, efficiency of ultrasonic oscillation energy, durability, etc. for industrial implementation. As a result of further studies, the inventors of the present invention have conducted further studies in order to develop a filtering device and another method that overcome these problems and can withstand industrial implementation.
If the material layer is rotated and only the lower end of the ultrasonic oscillation chip is immersed in the slurry,
The present invention was achieved based on the discovery that it is possible to prevent energy loss, make the equipment large-scale, and endure long-term continuous operation. It is an object of the present invention to generally provide a filter for removing solid foreign matter from a slurry containing ultrasonic waves, and in particular for removing solid foreign matter from a slurry containing solid foreign matter and cohesive fine particles. Another object is to provide an effective alternative method for removing solid foreign matter from a slurry of cohesive fine particles containing solid foreign matter. Accordingly, the object of the present invention is to provide a filtration machine body having a supply port and a discharge port for the treated material, a filtration chamber provided in the filtration machine body and equipped with a discharge pipe for the filtrate, and a filtration chamber provided in the filtration machine body and equipped with a discharge pipe for the filtrate. A cylindrical or disk-shaped material layer that constitutes a part of the surface of the material layer and is rotatably supported; An ultrasonic oscillation chip configured to face the entire surface of the material layer by rotation of the ultrasonic oscillator chip, and a holding chamber for penetrating the ultrasonic oscillation chip into the main body of the machine at the upper part of the machine body. This is achieved by an ultrasonic filter characterized in that the holding chamber is a gas chamber filled with gas except for the lower part of the ultrasonic oscillation chip. Therefore, the ultrasonic generator of the present invention has a liquid that adjusts the liquid level in the gas chamber so that at least the lower end of the ultrasonic oscillation chip is immersed in the material. The provision of a surface adjustment mechanism makes it even more useful. In addition, the purpose of the separate law in the present invention is to
The main body of the filter has a supply port and a discharge port for waste material,
A sieve chamber provided in the sieve body and equipped with a discharge pipe for the overtreated material; a cylindrical or disk-shaped material layer forming a part of the surface of the sieve chamber and rotatably supported; an ultrasonic oscillation chip configured to face only a part of the surface of the material layer at rest on the surface side of the material layer, and to face the entire surface of the material layer when the material layer rotates; and the ultrasonic oscillation chip is inserted into the main body of the ultrasonic machine through a gas chamber in the upper part of the main body of the ultrasonic machine so that at least the tip of the tip of the ultrasonic oscillator chip is immersed in the material to be covered. A slurry of cohesive fine particles containing solid foreign matter is supplied to the sonicator from the feed port of the material to be treated, and the material layer is rotated to oscillate ultrasonic waves, so that the ultrasonic oscillation chips face each other. Separately storing a slurry of cohesive fine particles from which solid foreign matter has been removed while dispersing cohesive particles on the surface of the material layer, and taking out the separately housed slurry through the overtreated material extraction pipe. The above object of the present invention can be easily achieved by adjusting the liquid level of the slurry in the gas chamber so that the liquid level of the slurry is below the ultrasonic oscillation chip. effectively achieved. The present invention will be explained in more detail below. The objects to be treated to which the present invention can be applied are generally various slurries, but in particular slurries containing larger solid foreign substances that should be removed with a slurry of fine particles, more specifically carbon black, dyes and pigments, fine particles, etc. A water slurry of cohesive fine particles such as silica contains solid foreign matter. The following is carbon black water slurry (hereinafter referred to as
It's called carbon slurry. ). In this case, the minimum particle diameter that can be captured is generally about 15 to 30 μm. The oscillation frequency of the ultrasonic waves used in the present invention is generally preferably in the low frequency range, but if the frequency is too low, it will fall into the audible range.
Approximately 25KHz is adopted. Next, the oscillation power per ultrasonic oscillation surface area is preferably about 10 to 55 watt/cm ² . The processing capacity tends to increase as this value increases, but if it becomes too large, the influence of the ultrasonic force on the material layer will be excessive, which may shorten the life of the material layer, so set an appropriate value depending on the situation. should be adopted. The amount of carbon black contained in the carbon slurry (hereinafter referred to as "slurry concentration") is determined by Since the amount of liquid passing through the material is small, carbon black with the same amount of foreign matter removed can be obtained. However, as the slurry concentration increases, the degree of influence of the ultrasonic force on the carbon black in the vicinity of the material layer decreases, making it difficult for the carbon black to be dispersed, and the carbon black that has aggregated on the surface of the material layer is captured and There may be cases where it does not pass through the layer. Therefore, it has been found that the most suitable range is usually 0.1 to 10%, preferably 1 to 5% by weight in the slurry. Regarding the pressure difference between the front side and the back side (inside the overpressure chamber) of the material layer (hereinafter referred to as "overpressure"), as the overpressure increases, the force that tries to pass through the material layer increases, but As the amount of carbon black that is pressed increases, the dispersion of carbon black in the vicinity of the material layer tends to be inhibited. The optimum value varies depending on the material layer thickness, material layer diameter, material layer rotation speed, oscillation power, etc., but in general, in the case of continuous operation, it is 0.1 to 5 Kg/cm ³ ·G, preferably 0.1 Kg/cm ³ to
Selected from a range of approximately 1.5Kg/ ^cm3 . What is important in the present invention is to rotate the material layers. The carbon black in the carbon slurry is dispersed by ultrasonic irradiation, but at the same time the material layer is also affected by the ultrasonic waves, wears out due to the erosion phenomenon, and eventually breaks. The degree of wear of the material due to the erosion phenomenon varies depending on various factors, but it also depends on the total ultrasonic irradiation time irradiated to the same location on the material layer. In other words, the lifespan of a material layer is determined by the total ultrasonic irradiation time irradiated to the same location.If the total ultrasound irradiation time is the same for the same location of the material layer, If the illuminated area (hereinafter referred to as "effective illuminated area") is large,
The lifespan of the material will be extended. For this purpose, it is possible to widen the material area and move the ultrasonic oscillation surface, but since the structure is complicated and there are many disadvantages, it is more advantageous to move the material layer. There is also a method of plane movement, but the best method for this method is to rotate the material layer around the central axis and move the effective receiving surface of the material layer relative to the ultrasonic oscillation chip surface. It's an easy method. The shape of the material layer, which rotates around the central axis and receives ultrasonic waves almost uniformly, is preferably cylindrical, polygonal, or disc-shaped. In this way, when the ultrasonic radiation of the material layer becomes discontinuous and the material receives ultrasonic waves continuously, the ultrasonic radiation receiving part of the material becomes hot and becomes more prone to rupture. Since this can be prevented, it is expected that the lifespan will be further extended than simply calculating the irradiation time. From this, it is better to increase the rotation speed as much as possible in terms of the lifespan of the material layer, but on the other hand, the minimum required speed is required to disperse the carbon black that is crimped onto the material by ultrasonic irradiation. A limited continuous ultrasound reception time is required. According to the study by the present inventors, the continuous ultrasonic irradiation time of the material layer is determined by the balance of processing capacity and material life, etc.
It is particularly preferable to select from the range of 0.02 seconds to 2 seconds. Therefore, the rotation speed of the material layer is calculated and selected based on the continuous ultrasonic irradiation time according to the shape of the material layer. The over-treated material such as carbon slurry passing through this material layer enters the pass chamber and is taken out of the system through the over-treated material extraction pipe that opens into the pass chamber. Therefore, part of the surface of the overchamber is made of a material layer, and the other surface is constructed to be liquid-tight, and is separated from the to-be-covered zone within the overflow machine. The most preferable overchamber is a cylindrical rotating body in which the cylindrical part is made of a material layer, both end surfaces of which are made of a material that does not allow liquid to pass through, and the central axis of rotation or the double inner tube inside the overchamber is made of a material that does not allow liquid to pass through. One example is one configured as an extraction pipe for the processed material. Furthermore, the present inventors have focused on the fact that the load resistance is smaller when the medium in contact with the ultrasonic oscillation chip is a gaseous body compared to when the medium in contact with the ultrasonic oscillation chip is a liquid. In order to prevent parts that are not involved in the dispersion of carbon black from coming into contact with the liquid, a holding chamber is provided at the top of the machine body to allow the ultrasonic oscillation chip to penetrate into the machine.
It is proposed to provide a gas chamber that holds the gas up to the upper part of this holding chamber, that is, to the lower part of the oscillation chip as far as possible. Furthermore, in the present invention, since the gas body is a compressible gas, the liquid level in the filter machine changes depending on the upstream pressure in the filter machine, etc.; It is even more preferable to employ a liquid level adjustment mechanism so that the liquid level, especially the liquid level in the gas chamber, does not change even if a factor that changes the liquid level in the gas chamber occurs. The most convenient adjustment mechanism is to open a water slurry discharge pipe at a height desired to set the liquid level in the filter, and provide a gas supply pipe for supplying and discharging gas to the gas chamber. In this case, in order to change the liquid level adjustment position within the apparatus main body, it is sufficient to change the insertion length of the water slurry discharge pipe into the apparatus main body, that is, the opening position.
Various other types of liquid level adjustment mechanisms may be used as appropriate, as long as they do not interfere with the present invention or other operations. Next, regarding the ultrasonic oscillation chip, due to the characteristics of ultrasonic waves, the length of one side of the ultrasonic oscillation chip is 1/4 of the wavelength of vibration in the material of the ultrasonic oscillation chip.
If it exceeds twice that, it is preferable to provide a slit in the ultrasonic oscillation chip in order to prevent foreign object vibration from occurring in the ultrasonic oscillation chip. Since the upper and lower surfaces of the slit provided in this ultrasonic oscillation chip also serve as ultrasonic oscillation surfaces, the longer the length of one side of the ultrasonic oscillation chip, the more ultrasonic energy is not effectively utilized for overaction. I will do it. When a slit is provided in the ultrasonic oscillation chip, if the liquid level is adjusted between the lower end surface of the ultrasonic oscillation chip and the lower end surface of the slit provided in the ultrasonic oscillation chip, the ultrasonic waves will not be effectively used for overaction. Energy can be minimized. Until now, it has been difficult to increase the size of ultrasonic generators because the ultrasonic generation energy in ultrasonic generators has a limit due to the performance of the ultrasonic oscillator. It is noteworthy that machines began to be made. In addition, in the present invention, a machine equipped with a rectangular ultrasonic oscillation chip has been described, but in a machine equipped with a cylindrical oscillation chip, the height of the ultrasonic oscillation chip is larger than the diameter of the lower end surface of the ultrasonic oscillation horn. The present invention is also effective when the end face diameter is larger. The present invention will be explained in more detail below based on the drawings. FIG. 1 is a schematic longitudinal cross-sectional view of one example of a filter according to the present invention. In the figure, reference numeral 1 denotes an ultrasonic generator driven by an ultrasonic oscillator 2. As shown in FIG. The vibrations generated in the ultrasonic generator 1 are transmitted to the oscillating chip 4 having an ultrasonic oscillating surface via the oscillating horn 3, and the oscillating horn 3 passes through the upper flange 5 of the machine. It is sealed with an "O" ring so that the distance between the surface (lower end surface) and the material layer 6 can be adjusted. The overtreatment chamber 7 is composed of a cylindrical material layer 6 and material side plates 9 and 11 that are made of a liquid-tight material and constitute both end surfaces thereof. is rotatably supported.
One of the side plates 9 is loosely connected to the waste discharge pipe 8 by means of an "O" ring 10. The other side plate 11 has bolts 1 fixed to the end face of the extraction pipe 8.
2 and a tightening nut 13. An appropriate number of through holes are provided in the area sandwiched between the material side plates 9 and 11 of the extraction tube 8, and their role is to guide the overtreated carbon slurry that has passed through the material layer 6 into the extraction tube 8. to play. The carbon slurry to be treated is supplied into the filter machine through the supply pipe 14. The over-treated material that has passed through the material layer 6 is discharged to the outside of the machine through an over-treated material extraction pipe 8, and the to-be-treated slurry that has not passed through the material layer 6 is discharged out of the machine through a to-be-treated material discharge pipe 15. This discharge pipe 15 is preferably inserted and fixed into an opening 16 fixedly provided in the main body of the filter. By changing the insertion length, that is, the opening position, the liquid level inside the filter can be changed.
Reference numeral 17 is a holding chamber in the upper part of the machine body for allowing the ultrasonic oscillation chip 4 to penetrate into the machine, and this holding chamber is preferably a gas chamber filled with gas. Gas is supplied into the filter machine from the gas supply pipe 18. Surplus gas out of the gas supplied into the filter machine is discharged from the machine through the waste discharge pipe 15 together with the waste slurry. Note that the ultrasonic oscillation chip 4 is provided with a slit 20, and the lower end of the slit 20 and the oscillation chip 4 are connected to each other.
It is particularly preferable to set the opening position of the waste material discharge pipe 15 such that the liquid level of the waste material is set between the lower end surface of the waste material and the lower end surface of the waste material. As detailed above, according to the present invention, damage to the material layer due to ultrasonic irradiation is suppressed as much as possible by rotating the material layer, and stable over-operation is possible over a long period of time. It is possible to stably and highly efficiently perform a passing operation in which the slurry itself is passed, such as when removing foreign substances from the slurry containing cohesive fine particles. Furthermore, in addition to the above, by making the holding chamber of the ultrasonic oscillation chip into a gas chamber and also providing a mechanism for adjusting the liquid level of the target material, we have created a large-scale industrial ultrasonic and ultrasonic device that efficiently utilizes ultrasonic energy. As a result, according to the present invention, it is possible to realize an extremely industrially advantageous diaphragm apparatus and diaphragm method using ultrasonic waves. Hereinafter, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to the following Examples unless it exceeds the gist thereof. Example In an ultrasonic device such as the device shown in FIG. 1 (ultrasonic frequency: 19.5 KHz, ultrasonic oscillation width: 20 μm,
Ultrasonic oscillation area: 20cm ² , Oscillation power per ultrasonic oscillation area: 30watt/cm ² , Cylinder diameter of material layer: φ150mm,
Material layer circumferential speed: 10cm/sec, material layer opening: 10μm
The slurry concentration and overpressure were adjusted as shown in Table 1 while supplying approximately 5 m ³ /hr of carbon slurry in which carbon black was suspended in water from the permeate supply pipe 14 using the holding chamber as a gas chamber. ,
The distance between the lower end surface of the ultrasonic oscillation chip and the material layer was varied, and the carbon slurry extracted from the over-processed material extraction tube 8 was collected and its amount was measured. The measurement results are shown in Table 1. In addition, experiments were conducted on cases in which ultrasonic waves were irradiated while rotating the material layer at a speed of 10 rpm, and cases in which the rotation of the material layer was stopped and only a portion of the layer was continuously irradiated with ultrasonic waves. The results are shown in Table-2.

【table】

【table】 [Brief explanation of drawings]

FIG. 1 is a schematic diagram of a longitudinal cross-section of an example of the filter machine of the present invention taken along a vertical plane including the material layer rotation axis. 1: Ultrasonic generator, 4: Ultrasonic oscillation chip,
6: Material, 7: Overchamber, 8: Overtreated material extraction pipe,
14: Toxic material supply pipe, 15: Toxic material discharge pipe,
17: Holding chamber, 19: Transmission machine body.

Claims (1)

[Scope of Claims] 1. A filtration machine body having a supply pipe and a discharge pipe for the treated material, a filtration chamber provided in the filtration machine body and equipped with a discharge pipe for the filtrate, and a part of the filtration chamber. A material layer that constitutes the surface of the material layer and is rotatably supported, the surface side of the material layer faces only a part of the surface of the material layer when it is at rest, and as the material layer rotates, the entire surface of the material layer 1. An ultrasonic transducer comprising: an ultrasonic oscillation chip configured to face the ultrasonic transducer; and a holding chamber in an upper part of the ultrasonic transducer body for penetrating the ultrasonic oscillation chip into the ultrasonic transducer main body. 2. The ultrasonic filter according to claim 1, wherein the holding chamber is a gas chamber filled with gas except for the lower part of the ultrasonic oscillation chip. 3. Claims characterized in that the main body of the ultrasonic generator is equipped with a liquid level adjustment mechanism that adjusts the liquid level in the gas chamber so that at least the lower end of the ultrasonic oscillation chip is immersed in the object. The ultrasonic filter according to item 2. 4. The ultrasonic wave according to claim 3, wherein the gas chamber has a gas supply pipe, and the waste material discharge pipe opens at a set liquid level of the gas chamber. Overtime. 5. The ultrasonic transducer according to any one of claims 1 to 4, wherein the lower end surface of the ultrasonic oscillation chip is rectangular. 6. A filtration machine body having a supply pipe and a discharge pipe for the treated material, a filtration chamber provided within the filtration machine body and equipped with a discharge pipe for the filtrate, and forming a part of the surface of the filtration chamber, A rotatably supported material layer, the surface side of the material layer facing only a part of the surface of the material layer when it is at rest, and being configured such that when the material layer rotates, it faces the entire surface of the material layer. The ultrasonic oscillating chip is placed in the upper part of the ultrasonic device body through a gas chamber so that at least the tip of the ultrasonic oscillating chip is immersed in the material to be treated. A slurry of cohesive fine particles containing solid foreign matter is supplied from the supply pipe of the material to be passed through the ultrasonic filter, and ultrasonic waves are oscillated while the material layer is rotated. While dispersing the cohesive fine particles on the surface of the material layer facing the oscillation chip, a slurry of the cohesive fine particles from which solid foreign matter has been removed is separately accommodated in the overflow chamber, and the separately housed slurry is removed from the overtreated material. A method for separating a slurry of cohesive fine particles containing solid foreign matter, characterized in that the slurry is taken out through an exit pipe. 7. An agglomerate containing solid foreign matter according to claim 6, characterized in that the liquid level of the slurry is adjusted in the gas chamber so that the liquid level of the slurry is below the ultrasonic oscillation chip. A method of separating slurry of fine particles.