Dry separation apparatus and dry separation method

Abstract

To provide a dry-type separation method which can reduce the frequency of maintenance and is friendly to the environment.SOLUTION: A dry-type separation apparatus according to the present invention includes: a body part including a separation tank; a feed part for feeding a separation object into the separation tank; and a discharge part for discharging the separation object after separation from the separation tank. The dry-type separation apparatus further includes: vibration means for vibrating the separation object fed into the separation tank; and transfer means for transferring the separation object after separation by the vibration to the discharge part. The vibration means vibrates the separation object part within a range of ±45 degrees in a horizontal direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a dry separation method and a dry separation apparatus for separating substances by specific gravity without using a liquid. [Background technology]

[0002] Construction waste, industrial waste, and disaster waste contain various different components. Separation of these components is necessary not only for the proper treatment of residues, but also for the recovery of rare metals, the refining of mineral resources, and the recycling of resources.

[0003] More specifically, technologies for separating granular mixtures and other materials based on density differences are needed to extract valuable materials from granular waste generated at manufacturing sites, or for the proper utilization of construction waste residues that are illegally dumped and disaster waste residues that are generated in large quantities due to disasters. Furthermore, in resource utilization, this separation technology is expected to be used to improve the quality of granular minerals such as rare metals, iron ore, copper ore, and coal.

[0004] To date, the main known separation methods are wet separation and dry separation methods based on the buoyancy and sinking phenomena of objects in water. For example, a recovery method is known that incorporates an impact crushing process to obtain two types of single-layer fine fragment aggregates corresponding to different specific gravities with high recovery rate and high purity (Patent Document 1).

[0005] Wet specific gravity separation technology is widely used both domestically and internationally. However, this technology has several drawbacks, including the need for wastewater treatment and drying processes, the high cost of adjusting the specific gravity of the liquid, deterioration of the working environment due to liquid leakage from the equipment, and difficulty of use in countries and regions with limited water resources. Dry specific gravity separation technology does not have these problems.

[0006] In dry gravity separation technology, some methods utilize the phenomenon of object buoyancy and sinking within a solid-gas fluidized bed. A solid-gas fluidized bed is a layer in which powder is fluidized, for example, by air blown from below, and its physical properties, such as density and viscosity, are similar to those of a liquid. When objects are introduced into this layer, relatively lighter objects float and relatively heavier objects sink, resulting in the buoyancy and sinking phenomenon, which allows these objects to be separated into upper and lower layers.

[0007] As an example of such a dry specific gravity separation method, a dry coal separation method is known in which a fluidized bed is formed by blowing gas onto a powder that serves as a fluidizing medium, and coal particles are introduced into the solid-gas fluidized bed to separate coal particles that have a density lower than the apparent density of the fluidized bed by causing them to float and coal particles with a higher density to settle (Patent Document 2). [Prior art documents] [Patent Documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 7-156148 [Patent Document 2] Japanese Patent Publication No. 2000-61398 [Overview of the Initiative] [Problems that the invention aims to solve]

[0009] However, conventional dry separation technologies all have problems such as high equipment costs and low efficiency. In addition, wet separation methods have problems such as environmental pollution from wastewater treatment, inability to be used in areas with limited water resources, and the need for wastewater treatment and drying processes after separation.

[0010] In addition, in the dry separation method using a fluidized bed to separate the object to be separated, depending on the object to be separated, there has been a problem that the pressure sensor of the blower for supplying air detects an abnormally high pressure and the blower stops urgently. When the blower stops abnormally, it is necessary to disassemble the device once to inspect the inside and then reassemble it again, which causes a major problem in practical use. Therefore, it is desired to develop a separation device and a separation method that can reduce the stop of the blower or the like and are maintenance-free for a long period of time.

[0011] Therefore, an object of the present invention is to provide a dry separation method that can reduce the frequency of maintenance and is environmentally friendly.

Means for Solving the Problems

[0012] As a result of investigating and intensively studying the cause of the emergency stop of the blower or the like, the inventor has found the dry separation method and the dry separation device of the present invention.

[0013] That is, the dry separation device of the present invention The materials to be separated are separated using a solid-gas fluidized bed in which the powder has been fluidized. has a main body part including a separation tank, The aforementioned an input part for inputting the object to be separated into the separation tank, and a discharge part for discharging the separated object to be separated from the separation tank, and is a dry separation device having The aforementioned vibration means for vibrating the object to be separated, and moving means for moving the object to be separated separated by the vibration to the discharge part, and the vibration means vibrates the object to be separated within a range where the direction of the added vibration is within ±45 degrees in the horizontal direction, and further has a gas dispersion plate at the bottom and / or the middle part of the separation tank, and the gas dispersion plate has a sandwich structure in which a cloth is sandwiched between perforated metals. The aforementioned [[ID=^]]

[0014] [[ID=^]] In a preferred embodiment of the dry separation device of the present invention, the moving means is an inclination provided at the bottom of the separation tank.

[0017] ​Furthermore, in a preferred embodiment of the dry separation apparatus of the present invention, the air velocity for blowing air to form a solid-gas fluidized bed is, More than 0 It is characterized by a speed of ~55 cm / s.

[0018] Furthermore, in a preferred embodiment of the dry separation apparatus of the present invention, the empty tower velocity is set to u0 and the minimum fluidization tower velocity of the powder is set to u mf In that case, u0 / u mf but More than 0 The airflow is characterized by being performed within the range of ~2.3.

[0019] Furthermore, the present invention provides a dry separation method that separates the material to be separated using a solid-gas fluidized bed in which powder is fluidized, and discharges the separated material to a discharge section. The process involves blowing air through a gas dispersion plate provided at the bottom and / or intermediate part of the separation tank forming the solid-gas fluidized bed, the gas dispersion plate having a sandwich structure in which cloth is sandwiched between perforated metal, The device is characterized by comprising the steps of: separating the object to be separated by vibrating a vibrating means that vibrates within a range of ±45 degrees in the horizontal direction; and discharging the separated object by a moving means that moves it to the discharge section.

[0020] Furthermore, in a preferred embodiment of the dry separation method of the present invention, the wind speed of the air blown to form the solid-gas fluidized bed is, More than 0 It is characterized by a speed of ~55 cm / s.

[0021] Furthermore, in a preferred embodiment of the dry separation method of the present invention, the empty tower velocity is set to u0 and the minimum fluidization tower velocity of the powder is set to u mf In that case, u0 / u mf but More than 0 The airflow is characterized by being performed within the range of ~2.3. [Effects of the Invention]

[0022] Furthermore, because this invention involves so-called dry separation, it can be used even in areas with limited water resources. This invention can also be used for the proper treatment of various mixed wastes and for the separation and recovery of valuable materials, including rare metals. Moreover, this invention offers the advantage of reducing the frequency of maintenance compared to conventional dry separation devices. [Brief explanation of the drawing]

[0023] [Figure 1] Figure 1 shows a schematic diagram of a dry separation apparatus in the first embodiment of the present invention. [Figure 2] Figure 2 shows a schematic diagram of a dry separation apparatus in a second embodiment of the present invention. [Figure 3] Figure 3 shows ΔP2 / ΔP1 for transverse and longitudinal vibrations. [Figure 4] Figure 4 shows the bulk density of each layer under transverse and longitudinal vibrations. [Figure 5] Figure 5 shows the relationship between wind speed and separation efficiency for lateral and longitudinal vibrations. [Figure 6] Figure 6 shows the relationship between the u0 / umf value and separation efficiency for transverse and longitudinal vibrations. [Figure 7] Figure 7 shows experimental results of pressure loss ratio (difference in clogging) for powders with different particle sizes (median diameters). [Modes for carrying out the invention]

[0024] The present invention relates to a dry separation apparatus comprising a main body section equipped with a separation tank, an input section for introducing a material to be separated into the separation tank, and an output section for discharging the separated material from the separation tank, wherein the apparatus further comprises a vibrating means for vibrating the material to be separated introduced into the separation tank, and a moving means for moving the material to be separated by the vibration to the output section, the vibrating means characterized in that it vibrates the material to be separated within a range of ±45 degrees in the horizontal direction.

[0025] First, the separation principle of the present invention will be described. The separation principle is to put the separation target into a solid-gas fluidized bed and use a powder fluidization medium similar to liquid specific gravity separation, that is, a solid-gas fluidized bed, to separate it according to its density (utilizing object floating and sinking), or to fluidize the separation target itself to separate the separation target (utilizing density segregation). The former solid-gas fluidized bed is intended to have properties similar to a liquid by fluidizing powder. First, the case of using the former powder fluidization medium will be described.

[0026] The apparent density ρ of the fluidized bed fb [[ID=?]]is expressed by the following formula. ρ fb =W p / V f =(1 - ε f f)ρ p Here, W p is the particle weight of the fluidization medium, V f is the volume during fluidization, ε f is the porosity during fluidization, and ρ p is the particle density of the fluidization medium.

[0027] When an object with density ρ fb is mixed in a fluidized bed having such an apparent density ρ s , the object component with ρ s < ρ fb will float on the upper part of the fluidized bed, and the object component with ρ s > ρ fb will sink to the lower part of the fluidized bed. And the object component with ρ s = ρ fb will float in the middle part of the fluidized bed. By utilizing this, the specific gravity separation of at least two kinds of objects is carried out.

[0028] On the other hand, in the case of separating the separation target by fluidizing the separation target itself (utilizing density segregation), it is as follows. This is to fluidize the separation target itself as if it were a powder that forms a solid-gas fluidized bed medium to perform separation.

[0029] In other words, conventionally, separation of the target material was performed solely by blowing air, but there were cases where separation of the target material was difficult with air alone. However, in the present invention, even in such cases, the target material can be separated and discharged outside the device.

[0030] Based on this separation principle, the objects that can be separated in the present invention are not particularly limited. Examples of objects that can be separated include various mineral resources, industrial products, and shredder dust. Specifically, examples include waste, minerals, agricultural products, industrial products, metal powders, mineral powders, rubbers, plastics, and glass. Examples of various mineral resources include ores such as silica and pyrophyllite, and raw coal mined from coal mines. Examples of shredder dust include household waste, automobiles, and shredder dust from home appliances. The size of the objects to be separated is not particularly limited, but in the present invention, by optimizing vibration or the vibration recovery mechanism, it is possible to separate granular mixtures and other objects that are easily affected by the movement of the fluidizing medium in the solid-gas fluidized bed. Therefore, the present invention is particularly effective for objects that are unstable in terms of floating and sinking with conventional dry separation techniques, such as objects with a density ratio of less than 2.0 (small density difference) or a particle size of 10 mm or less.

[0031] The separation target may be from any of these sources, but if the separation target is contaminated, it is preferable to wash it before separation. This is because, according to the separation method of the present invention, the components of the separation target are separated mainly by their specific gravity differences, and if the separation target is contaminated, the specific gravity may fluctuate.

[0032] Furthermore, it is necessary to dry the materials to be separated after washing. When separating materials for recycling, it is preferable to use shredded materials (such as those produced by a shredder) after drying, due to the size of the equipment and other factors.

[0033] In the present invention, the separation tank is not particularly limited in shape, etc., as long as it can form the solid-gas fluidized bed or the fluidized bed, whether in the case where the solid-gas fluidized bed is formed using a powder medium or in the case where the material to be separated itself forms the fluidized bed. Furthermore, in the present invention, the separation tank can be at least one of rectangular, cylindrical, or triangular prism shapes.

[0034] If the separation tank is rectangular in shape, the input section for the material to be separated may be located above one horizontal end of the tank, and the discharge section may be located on the opposite side of the horizontal end of the tank.

[0035] If the separation tank is cylindrical or triangular prism-shaped, the input section for the material to be separated may be located in the center of the tank, and the discharge section may be located on the outer side of the tank.

[0036] Furthermore, in the present invention, preferably, the separation tank has one or more partitions. The one or more partitions are preferably installed inside the dispersion tank parallel to the direction in which the object to be separated is to be moved. The partitions are expected to promote the "wall effect" on the object to be separated within the separation tank. The wall effect is the effect that the wider the area in contact with the wall of the object to be separated, the greater the propagation of vibration to the object to be separated. In other words, if the entire fluidized bed or separation tank is vibrated without partitions that allow for the vibration effect in areas where vibration does not propagate, it is difficult to obtain the vibration effect in areas far from the side walls or areas far (high) from the bottom air dispersion plate (gas dispersion plate). From this viewpoint, compared to vibrating only the entire separation tank, it is possible to further enhance the separation effect by vibrating both the entire separation tank and the partitions. It is even more preferable to install the partition members parallel to the direction of movement, and to have these members vibrate in sync with the vibration of the entire fluidized bed. Thus, in the present invention, by installing the component, it becomes possible to implement a method that allows vibration to have an effect even inside the fluidized bed.

[0037] Furthermore, the present invention may have an input unit for introducing the material to be separated into the separation tank, and a discharge unit for discharging the separated material from the separation tank. The input unit is not particularly limited as long as it can accept the material to be separated. In the present invention, the vibration means for vibrating the material to be separated is: The object to be separated The method is not particularly limited as long as it can vibrate the material. For example, a vibration motor can vibrate the material to be separated within a range of ±45 degrees horizontally. In this invention, the vibration was limited to a range of ±45 degrees horizontally because it was predicted that the blower would stop due to clogging of the gas dispersion plate, and it was thought that the cause of clogging was that the filter cloth constituting the gas dispersion plate was being struck against the powder by vertical vibration. By rotating the vibration motor that generates the vibration by 90° from the conventional orientation and changing the direction of the added vibration from the vertical direction to the horizontal range of ±45 degrees relative to the device, it was possible to significantly suppress clogging after the powder has fluidized, as will be clear from the examples described later. Furthermore, it was confirmed that the separation efficiency of granular mixtures was equivalent to that of vertical vibration even with vibration in this range. The amplitude of the horizontal vibration within the range of ±45 degrees horizontally can preferably be 0.25 to 4.00 mm, more preferably 0.50 to 2.00 mm, from the viewpoint of reducing clogging and maintenance.

[0038] Furthermore, the vibration frequency within a range of ±45 degrees horizontally can be appropriately adjusted depending on the type of object to be separated, but from the viewpoint of reducing clogging and maintenance, it is preferably 10 to 30 Hz, more preferably 15 to 25 Hz. Also, from the viewpoint of reducing clogging and maintenance, sinusoidal vibration is preferred as the vibration.

[0039] Furthermore, the vibration intensity G within a range of ±45 degrees in the horizontal direction can be defined as follows. Vibration intensity G = vibration acceleration (amplitude x angular velocity 2 ) / gravitational acceleration In the present invention, from the viewpoint of reducing clogging and maintenance, the vibration intensity G within a range of ±45 degrees in the horizontal direction is preferably 0.25 to 3.00, and more preferably 0.5 to 1.5.

[0040] Furthermore, the present invention includes a moving means for moving the separated object to the discharge section. In the present invention, the moving means can be used to move the separated object in the separation tank toward the discharge section. Examples of the moving means include those based on the structure of the separation tank, those utilizing airflow, and those using movable members installed in the separation tank. However, it is not particularly limited as long as it applies force to the separated object to move it toward the discharge section.

[0041] In the present invention, for example, as a means of movement, a slope provided at the bottom of the separation tank is preferable, from the viewpoint of quickly moving the separated material to the discharge section. Furthermore, the slope can preferably be directed from the input section to the discharge section, from the viewpoint of more efficiently moving the separated material to the discharge section. This allows the material to be moved smoothly from a higher position on the slope to a lower position by its own weight, and consequently, the material to be separated can be continuously separated from the input section to the discharge section.

[0042] Furthermore, in the present invention, the moving means is characterized by moving the object to be separated in the separation tank toward the discharge section. For example, a movable member installed in the separation tank can first discharge the floating material that has floated in the fluidized bed formed by the solid-gas fluidized bed or the object to be separated itself, and then discharge the settled material that has settled in the fluidized bed formed by the solid-gas fluidized bed or the object to be separated itself.

[0043] More preferably, the dry separation apparatus of the present invention may have a gas dispersion plate at the bottom and / or in the middle of the separation tank. For example, the gas dispersion plate may be a woven or nonwoven fabric derived from metal, natural fibers, synthetic fibers such as plastic, a porous metal plate, a porous ceramic plate, or a combination of these with a reinforcing material such as a metal plate, or a combination of two or more of these. From the viewpoint of cost, preferably, the dispersion plate is a combination of cloth and a reinforcing material such as a metal plate. Furthermore, in a preferred embodiment of the dry separation apparatus of the present invention, from the viewpoint of reducing clogging and reducing maintenance, the gas dispersion plate is characterized by a sandwich structure in which cloth is sandwiched between perforated metal.

[0044] Furthermore, in the present invention, the manner of inclination of the gas dispersion plate, such as the bottom of the separation tank or a porous dispersion plate, is not particularly limited. For example, the dispersion plate may be concave or shaped like a mountain to make the height of the container different in the center and outer periphery. By concave or shaped like a mountain, the airflow velocity of the gas introduced in the center and outer periphery of the container can be changed, thereby circulating the material to be separated and making the segregation of the material to be separated more pronounced.

[0045] To further explain circulation, please note the following: Unless otherwise specified, the circulation and circulating flow referred to here do not refer to the circulating flow of the gas itself, but rather to the circulating flow of the material being separated. In other words, when gas is introduced from the bottom of the material being separated, if the gas can pass more easily through the center of the container bottom than near the walls, the rise of gas bubbles in the center will be significant, and this rise of bubbles will cause the material being separated to rise in the center and descend near the walls, forming a circulating flow. Conversely, if the gas can pass more easily near the walls, the rise of bubbles near the walls will be significant, forming a circulating flow where the material being separated rises near the walls and descends in the center. Furthermore, when using a material being separated with certain characteristics, a circulating flow that changes in an S-shape in the height direction may also occur. In this invention, the term refers to a broad concept that includes such circulation.

[0046] Furthermore, if the gas's passability is the same in the cross-sectional direction (between the center and near the walls), the gas will rise uniformly in the cross-sectional direction as bubbles, and the material to be separated will become fluid, but the circulating flow described above will not be formed. Even in the absence of such circulating flow, separation based on differences in specific gravity or size will occur, but the role of circulating flow is to make that separation more pronounced.

[0047] Furthermore, the dry separation apparatus of the present invention may have a blowing means provided at the bottom and / or the intermediate portion. In a preferred embodiment of the dry separation apparatus of the present invention, the air velocity for blowing air to form the solid-gas fluidized bed is characterized by being greater than 0 to 55 cm / s, and more preferably 10 to 30 cm / s, as will be clear from the examples described later, such that the separation efficiency is in the range of 50%.

[0048] Furthermore, in the present invention, with respect to the airflow of the air blowing means, the minimum fluidization air velocity of the powder is set to u0. mf In that case, u0 / u mf However, this is one of the factors that control the separation. Generally, if the empty tower velocity is set to a value equal to or near the minimum fluidization empty tower velocity, the density distribution of dust components present in the fluidized bed formed by the solid-gas fluidized bed or the object to be separated itself becomes narrower, and if the empty tower velocity is further increased, the density distribution of dust components present in the solid-gas fluidized bed becomes wider. Note that the empty tower velocity is the velocity of the airflow generated in the separation tank.

[0049] First, let's explain the case using a solid-gas fluidized bed as an example. When using a solid-gas fluidized bed (utilizing the buoyancy of objects), in a preferred embodiment of the present invention, the value of u0 / umf can be, for example, in the range of 0 to 2.3, and more preferably in the range of 0.4 to 1.3, which results in a separation efficiency of 50%, as will be clear from the examples described later. This is because, within this range, a stable solid-gas fluidized bed can be formed, and clogging and maintenance can be reduced.

[0050] Furthermore, when using a solid-gas fluidized bed (utilizing the buoyancy of objects), if multiple powders are fluidized, it is preferable to perform the process under a u0 / umf value such that the multiple powders are substantially mixed uniformly. This is because if they are not substantially mixed uniformly, the apparent density will decrease towards the top of the solid-gas fluidized bed and increase towards the bottom, resulting in a tendency for the density distribution of components located in the middle layer of the solid-gas fluidized bed to be larger.

[0051] When using a solid-gas fluidized bed (utilizing the buoyancy of objects), the type of powder forming the solid-gas fluidized bed is not particularly limited depending on the type of object to be separated. For example, the powder can be at least one selected from the group consisting of unibeads, glass beads, zircon sand, polystyrene particles, and steel shot.

[0052] On the other hand, when a fluidized bed formed by the object to be separated itself is used (utilizing density segregation), the value of u0 / umf can be, for example, in the range of 0.5 to 1.5, more preferably in the range of 0.75 to 1.25. This is because, within this range, a stable fluidized bed formed by the object to be separated itself can be formed while reducing clogging and maintenance.

[0053] There are no particular limitations on the average particle size of the powder used in the solid-gas fluidized bed, or the material to be separated (in the case of powder) when using a fluidized bed formed by the material to be separated itself. However, from the viewpoint of performing fluidization of the powder at a relatively low empty-stack velocity and suppressing powder aggregation due to adhesion, it is preferably 0.05 to 10.00 mm, and more preferably 0.1 to 1.0 mm.

[0054] Next, an example of the dry separation method of the present invention will be described as follows. The dry separation method of the present invention is a dry separation method that separates a target material using a solid-gas fluidized bed in which powder has been fluidized, and discharges the separated target material to a discharge section, and is characterized by comprising the steps of: separating the target material by vibrating it using a vibrating means that vibrates within a range of ±45 degrees in the horizontal direction; and discharging the separated target material by a moving means that moves it to the discharge section. For the powder, the solid-gas fluidized bed, the target material, the input section, and the discharge section, refer to the description of the dry separation apparatus equipped with a separation tank described above.

[0055] In the present invention, for example, the object to be separated can be vibrated by a vibration motor within a range of ±45 degrees horizontally. As long as the object to be separated can be vibrated within a range of ±45 degrees horizontally, the solid-gas fluidized bed or the fluidized bed formed by the object to be separated itself may be vibrated, or the separation tank may be vibrated. In the present invention, the vibration was set within a range of ±45 degrees horizontally because it was predicted that the blower would stop due to clogging of the gas dispersion plate, and it was thought that the cause of clogging was that the filter cloth constituting the gas dispersion plate was being struck against the powder by vertical vibration. By rotating the vibration motor that generates the vibration by 90° from the conventional orientation and changing the direction of the added vibration from the vertical direction relative to the device to a range of ±45 degrees horizontally, it was possible to significantly suppress clogging after the fluidization of the powder, as will be clear from the examples described later. In addition, the configuration used in the dry separation apparatus of the present invention, including the partitions mentioned above, can be applied to the dry separation method of the present invention when it comes to vibration, etc.

[0056] In the present invention, for example, as a means of movement, a slope provided at the bottom of the separation tank is preferable, from the viewpoint of quickly moving the separated material to the discharge section. For details on the separation tank, please refer to the description of the dry separation apparatus of the present invention above. Furthermore, the slope is preferably directed from the input section to the discharge section, from the viewpoint of more efficiently moving the separated material. This allows the material to be moved smoothly from a higher position on the slope to a lower position by its own weight, and consequently, the material to be separated can be continuously separated from the input section to the discharge section.

[0057] Furthermore, in the present invention, the moving means is characterized by moving the object to be separated in the separation tank toward the discharge section. For example, a movable member installed in the separation tank can be used to first discharge the floating material that has floated in the solid-gas fluidized bed, and then discharge the settled material that has settled in the solid-gas fluidized bed.

[0058] Furthermore, in a preferred embodiment of the dry separation method of the present invention, the wind speed of the air blown to form the solid-gas fluidized bed is characterized by being greater than 0 to 55 cm / s. For the wind speed of the air blown to form the solid-gas fluidized bed, refer to the description of the dry separation apparatus of the present invention described above.

[0059] Furthermore, in a preferred embodiment of the dry separation method of the present invention, the empty tower velocity is set to u0 and the minimum fluidization tower velocity of the powder is set to u mf In that case, u0 / u mf The airflow is performed in a range of greater than 0 to 2.3. The minimum fluidization velocity of the powder is set to the empty tower velocity u0. mf In that case, u0 / u mf For the values, please refer to the description of the dry separation apparatus of the present invention above. [Examples]

[0060] The present invention will be described in more detail below with reference to examples, but it is not intended to be interpreted as being limited to the following examples.

[0061] Example 1 First, a dry separation device was manufactured that utilizes a slope provided at the bottom of the separation tank as a means of movement. Figure 1 shows one embodiment of the dry separation device according to the present invention. In Figure 1, the dry separation device comprises a separation tank 3, an input section 5 for the material to be separated, an output section 7 for the material to be separated, a vibration means (only vibration 20 is shown in the figure. In the device of the present invention, the direction of vibration can be operated within a range of ±45 degrees horizontally), and an air blower 30. In Embodiment 1, the separation tank 3 is rectangular. The device generates a solid-gas fluidized bed 4 formed by the material to be separated or by the material to be separated itself within the separation tank 3, separates low-density and high-density objects of the material to be separated in the solid-gas fluidized bed 4 formed by the material to be separated or by the material to be separated itself, and discharges them outside the device from the output section 7. The vibration means vibrates the fluidized bed 4 and the material to be separated in the separation tank. The movement means facilitates the movement of the material to be separated from the chamber closer to the input section to the chamber closer to the output section.

[0062] The discharge unit 7 is equipped with discharge ports 7a and 7b whose installation positions are set based on the density differences of multiple types of objects contained in the object to be separated. Discharge ports 7a and 7b are, for example, slits. The number of discharge ports can be set to the number of types to be discharged after the object to be separated, instead of a predetermined number of types based on density differences.

[0063] In Example 1, as an example of a means of movement, a bottom 9 is shown with a slope that decreases from the part closest to the input section 5 to the part closest to the discharge section 7.

[0064] Furthermore, the blower unit 30 of the dry separation device can also be considered part of the moving mechanism, as it improves separation efficiency by sending an airflow 33 with a preset wind speed from the air chamber 31 into the separation tank 3 and promotes the movement of the powder to the right.

[0065] The discharge unit 7 includes an outlet 7a for objects with relatively low density and an outlet 7b for objects with relatively high density. Although there are two outlets 7a and 7b, the number and position of the outlets can be changed depending on the number of types of objects to be separated based on the difference in density.

[0066] In the blower unit 30, the air chamber 31 may be divided into multiple sections, and the airflow velocity of the airflow 33 may be set to gradually decrease from the chamber closest to the input to the chamber closest to the discharge.

[0067] Using the above device, u0 / u mf The value of is set to 1, and the vibration intensity G is set to 1.2. The material to be separated is a granular material with a particle size of 10 mm or less, which has been difficult to separate in the past, and is heavy mineral sand (2.5 g / cm³). 3 ) and silica sand (1.5g / cm³) 3 When we attempted to separate substances with small density differences, we found that even those that could not be separated by airflow alone could be separated.

[0068] Example 2 Next, to investigate the effect of vibration direction on clogging of the filter cloth, the following experiment was conducted to examine the clogging suppression effect. A small cylindrical apparatus, as shown in Figure 2, was used as the experimental apparatus. This apparatus consists of a cylindrical column with an inner diameter of 100 mm, two vibration motors on the left and right, and an inverter to control the rotation speed of the motors, and compressed air is supplied from a compressor. First, air was blown into the cylindrical column with an empty column, and the pressure loss ΔP1 of the air dispersion plate in the initial state was measured. Next, fine coal pulverizer with a particle size of 0.05 to 0.5 mm was packed as a sample to a layer height of 100 mm, and after fluidizing it for 2 hours by applying air blowing and vibration, the pressure loss ΔP2 of the air dispersion plate was measured again after removing the sample from the apparatus. Then, the pressure loss ratio ΔP2 / ΔP1 before and after fluidization was calculated. A larger value in this ratio indicates that clogging has progressed. Figure 3 shows ΔP2 / ΔP1 when longitudinal vibration and transverse vibration (vibration within a range of ±45 degrees in the horizontal direction) are applied. In the case of longitudinal vibration, ΔP2 / ΔP1 = 14.4 was observed, indicating a large value, and that clogging progressed as fluidization occurred. On the other hand, in the case of transverse vibration, ΔP2 / ΔP1 = 1.1, and there was almost no increase in the pressure loss of the air dispersion plate after fluidization, demonstrating a significant success in suppressing clogging.

[0069] Example 3 Next, regarding separation efficiency, the following experiment was conducted to investigate whether granular mixtures could be separated by transverse vibration in the same way as by longitudinal vibration. The same apparatus as in Example 2 was used, and construction waste residue with a particle size of 0.1 to 4 mm was used as the sample. It was confirmed that this construction waste residue could not be separated into organic matter and gravel by air blowing alone. The sample was packed into a column to a layer height of approximately 100 mm, treated for 10 minutes with air blowing and vibration, and then collected in 10 layers of 10 mm each from the top using a cyclone, and the bulk density of each layer was measured. Figure 4 shows the bulk density of each layer against wind speed. In the case of longitudinal vibration shown in the upper panel, density segregation occurred at low wind speeds of 10 cm / s, where the bulk density of the upper layer was small and the bulk density of the lower layer was large, and more pronounced segregation was observed at wind speeds of 30 to 60 cm / s. This indicates that organic matter such as wood chips, which has a lower density, moved to the upper layer, and gravel, which has a higher density, moved to the lower layer, and the two were separated. On the other hand, in the case of the lower lateral vibration, density segregation was slow at a moderate wind speed of 30 cm / s, but at high wind speeds of 40 and 60 cm / s, density segregation occurred throughout the entire layer, similar to the longitudinal vibration. This revealed that separation of construction waste residue is possible even when the vibration is changed to the lateral direction.

[0070] Example 4 Next, we investigated the relationship between air velocity and separation efficiency under lateral and longitudinal vibrations. Specifically, we used a mixed powder of glass powder and stainless steel powder to investigate the relationship between air velocity and separation efficiency under lateral and longitudinal vibrations. The experimental apparatus was the same as in Figure 2 of 1). The above mixed powder was packed into a cylindrical column to a layer height of approximately 100 mm, and after processing for 10 minutes with added airflow and vibration, the mixture was collected in 10 layers of 10 mm each from the top using a cyclone. After measuring the bulk density of each layer, the separation efficiency was calculated, with 100% defined as the case where the glass powder completely moved to the upper layer and the stainless steel powder completely moved to the lower layer.

[0071] Figure 5 shows the separation efficiency against wind speed. In the case of longitudinal vibration, the separation efficiency was approximately -70% when the wind speed was zero or extremely low, and reverse density segregation occurred, which is contrary to the density difference, with stainless steel powder moving to the upper layer and glass powder to the lower layer. On the other hand, such reverse density segregation did not occur in the case of transverse vibration. At other wind speeds, density segregation occurred as expected from the density difference, with glass powder moving to the upper layer and stainless steel powder to the lower layer. Therefore, from the perspective of separation technology, reverse density segregation is an unsuitable phenomenon, and transverse vibration is considered to have an advantage over longitudinal vibration in that it can suppress it.

[0072] Example 5 Next, we investigated the relationship between air velocity (u0 / umf) and separation efficiency under lateral and longitudinal vibrations. Specifically, we used a mixed powder of glass powder and stainless steel powder to investigate the relationship between u0 / umf and separation efficiency under lateral and longitudinal vibrations. The experimental apparatus was the same as in Figure 2 of 1). The above mixed powder was packed into a cylindrical column to a layer height of approximately 100 mm, and after processing for 10 minutes with added airflow and vibration, the mixture was collected in 10 layers of 10 mm each from the top using a cyclone. After measuring the bulk density of each layer, the separation efficiency was calculated, with 100% defined as the case where the glass powder completely moved to the upper layer and the stainless steel powder completely moved to the lower layer.

[0073] Figure 6 shows the separation efficiency for u0 / umf. In the case of longitudinal vibration, the separation efficiency was approximately -70% when u0 / umf was zero or extremely small, and reverse density segregation occurred, which is contrary to the density difference, with stainless steel powder moving to the upper layer and glass powder to the lower layer. On the other hand, such reverse density segregation did not occur in the case of transverse vibration. Furthermore, at other wind speeds, density segregation occurred as expected from the density difference, with glass powder moving to the upper layer and stainless steel powder to the lower layer. Therefore, from the perspective of separation technology, reverse density segregation is an unsuitable phenomenon, and transverse vibration is considered to have an advantage over longitudinal vibration in that it can suppress it. Additionally, while separation efficiency was high in longitudinal vibration at u0 / umf = 1 to 2, a difference was also observed in transverse vibration where separation efficiency was high at a smaller u0 / umf of u0 / umf = 0.6 to 1.2 than in longitudinal vibration.

[0074] Example 6 Next, we investigated the differences in clogging with powders of different particle sizes (median diameters). As mentioned above, when longitudinal vibration was applied, it became clear that clogging of the air dispersion plate progressed as the powder fluidized. Here, we used powders of different particle sizes (silica sand with median diameters of 43 μm, 75 μm, 160 μm, and 264 μm) and investigated the differences in clogging when longitudinal vibration was applied. The experimental apparatus was the same as in Figure 2 of 1), and the experimental method was also the same. First, air was blown into the cylindrical column with an empty column, and the pressure loss ΔP1 of the air dispersion plate in the initial state was measured. Next, one of the above types of silica sand was packed to a layer height of 100 mm, and after fluidization for 2 hours with the application of air and vibration, the pressure loss ΔP2 of the air dispersion plate was measured again after the silica sand was removed from the apparatus. Then, the pressure loss ratio ΔP2 / ΔP1 before and after fluidization was calculated. A larger value of this ratio indicates that clogging has progressed. Figure 7 shows the ΔP2 / ΔP1 ratio with respect to the median diameter of the powder. At a median diameter of 43 μm, the ΔP2 / ΔP1 value was approximately 12, and at a median diameter of 75 μm, it was approximately 6, indicating that clogging progressed due to the small powder size. On the other hand, at median diameters of 160 μm and 264 μm, the ΔP2 / ΔP1 value was almost 1, indicating that clogging did not progress due to the large powder size. As a result, it was found that clogging can be suppressed even when fluidization is performed by adding longitudinal vibration for powders with a median diameter of 160 μm or larger.

[0075] As described above, it has been found that maintenance can be reduced by the dry separation apparatus and method of the present invention. [Industrial applicability]

[0076] This invention is applicable to the proper treatment of various types of mixed waste and the separation and recovery of valuable materials, including rare metals. It can be used in fields requiring the separation of granular mixtures based on density differences, such as extracting valuable materials from granular waste generated in manufacturing sites. Furthermore, it is expected to be useful in the proper treatment of construction waste residues, which have recently become a problem due to illegal dumping, and disaster waste residues generated in large quantities by major earthquakes. Looking overseas, this technology is also expected to be used to improve the quality of granular minerals such as rare metals, iron ore, copper ore, and coal. [Explanation of symbols]

[0077] 3 Separation tank 4. A fluidized bed formed by a solid-gas fluidized bed or the object to be separated itself. 5 Input section 7 Discharge section 7a Outlet for separation target with relatively low density 7b Separation targets with relatively high density are discharged at the outlet. 9 Bottom 20 Vibration means 30. Air blower (air blowing means) 31 Air chamber 33. Airflow (ventilation) Z Direction of movement of the object to be separated

Claims

1. A dry separation apparatus comprising a main body having a separation tank for separating a material to be separated using a solid-gas fluidized bed in which powder is fluidized, an input section for introducing the material to be separated into the separation tank, and an output section for discharging the separated material from the separation tank, wherein the apparatus further comprises a vibrating means for vibrating the material to be separated introduced into the separation tank, and a moving means for moving the material to be separated by the vibration to the output section, wherein the vibrating means vibrates the material to be separated within a range of ±45 degrees horizontally, and further comprises a gas dispersion plate at the bottom and / or in the middle of the separation tank, wherein the gas dispersion plate has a sandwich structure in which cloth is sandwiched between perforated metal.

2. The apparatus according to claim 1, wherein the moving means is a slope provided at the bottom of the separation tank.

3. The apparatus according to claim 1 or 2, wherein the wind speed of the air blower for forming the solid-gas fluidized bed is greater than 0 to 55 cm / s.

4. Sky tower velocity u ０ The minimum fluidization velocity of the powder is u ｍｆ In that case, u ０ / u ｍｆ The apparatus according to claim 3, characterized in that the airflow is performed in a range of greater than 0 to 2.

3.

5. A dry separation method comprising separating a material to be separated using a solid-gas fluidized bed formed by fluidizing powder, and discharging the separated material to a discharge section, the dry separation method comprising: a step of blowing air through a gas dispersion plate provided at the bottom and / or in the middle of a separation tank forming the solid-gas fluidized bed, the gas dispersion plate having a sandwich structure in which cloth is sandwiched between perforated metal; a step of vibrating the material to be separated using a vibrating means that vibrates within a range of ±45 degrees in the horizontal direction to separate the material; and a step of discharging the separated material to a discharge section using a moving means.

6. The method according to claim 5, wherein the wind speed of the air blown to form the solid-gas fluidized bed is greater than 0 to 55 cm / s.

7. Sky tower velocity u ０ The minimum fluidization velocity of the powder is u ｍｆ In that case, u ０ / u ｍｆ The method according to claim 6, characterized in that the airflow is performed in a range of greater than 0 to 2.3.

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