JP5619549B2 - Fluidized bed apparatus and filter removal method in fluidized bed apparatus - Google Patents

Description

  The present invention relates to a fluidized bed apparatus used when producing fine granules, granules and the like of pharmaceuticals, agricultural chemicals, foods and the like.

  A fluidized bed apparatus is generally granulated, coated, dried, etc. while forming a fluidized bed by floating and flowing a granular material in a fluidized bed container with a gas (fluidized gas) introduced from the bottom of the fluidized bed container. The process is performed. This type of fluidized bed apparatus includes those that involve rolling, jetting, stirring, and the like of powder particles (referred to as a combined fluidized bed apparatus).

  In this type of fluidized bed apparatus, a filter unit for separating the particulate particles from the solid-gas mixed gas containing the particulate particles is disposed above the processing chamber in the fluidized bed container. As a filter of the filter section, in addition to a woven filter called a bag filter (Patent Documents 1 and 2 below), a cartridge type filter in which a breathable resin filter medium or a metal filter medium is formed in a cylindrical shape and held on a holding member is used. It is used (the following patent documents 3-7).

  When the fluidized bed apparatus is operated for a predetermined time, the granular particles adhere to and stay on the filter medium surface of the filter, and the filtration performance decreases. Therefore, the filter is removed every predetermined time, and the particulate matter adhered to the surface of the filter medium is removed to recover the filtration performance. This removal operation is usually performed by shaking the filter up and down with an actuator such as an air cylinder or hydraulic cylinder in the case of a bag filter (shaking). In the case of a cartridge type filter, compressed air is supplied to the inside of the filter. (Back washing). In addition, there are two types of bug filter payout mechanisms: single shaking method and twin shaking method. The former shakes the fluidized bed device at the time of payment and shakes the entire bug filter. The filter chamber is divided into two, and the filter of the other filter chamber is shaken when exhausting through the filter of one filter chamber without stopping the fluidized bed apparatus.

  Further, in the above fluidized bed apparatus, in order to easily and efficiently produce a granulated product having uniform properties and a small specific volume, a granulation using air pulsation waves as a fluidized gas introduced from the bottom of the fluidized bed container is used. A grain method has been proposed (Patent Documents 8 and 9 below).

Japanese Patent Laid-Open No. 11-223458 JP 7-148410 A JP 2001-817 A JP 2000-42336 A Japanese Patent Laying-Open No. 2005-152883 JP-A-9-187613 JP 2000-185209 A Japanese Patent Laid-Open No. 10-329136 Japanese Unexamined Patent Publication No. 7-19728

  For example, a treatment using fine particles having a small particle diameter as a raw material (for example, a granulation treatment using fine particles of 50 μm or less as a raw material, a coating treatment targeting fine core particles of 150 μm or less), or a high-content oil / fat raw material In granulation processing using high particles as a raw material, in order to ensure good fluidity of the granular particles in the fluidized bed container and to produce a granular product with good processing quality, It is effective to use a gas pulsation wave as the fluidizing gas introduced into the inside. However, in a process using fine particles or highly sticky particles as a raw material, the amount of particles adhering and staying on the filter increases, and the filter medium of the filter may be clogged in a relatively short operation. In such a case, it is necessary to perform a filter drop-out operation every relatively short time, and the processing operation becomes complicated. In particular, in the case of the single shaking method of the bug filter, the fluidized bed apparatus must be stopped for each payout operation. Therefore, if the number of payout operations increases, the processing efficiency decreases accordingly.

  In addition, when the amount of particles staying attached to the filter increases, the content of components in the product varies, and the particles staying attached to the filter are dropped in a aggregated state by the dropping operation and returned to the fluidized bed, Quality uniformity such as product content and particle size distribution may be reduced.

  The problem of the present invention is to suppress the adhesion and retention of the granular particles on the filter during the operation of the fluidized bed apparatus, to reduce the number of shake-off operations by shaking and backwashing in the processing process, and to simplify the processing operation. It is intended to improve the processing efficiency and to improve the uniformity of the quality such as the component content and particle size distribution of the granular product.

In order to solve the above problems, the present invention provides a fluidized bed apparatus in which at least one of granulation, coating, and drying is performed while floating and flowing a granular material with a fluidized gas in a fluidized bed container. A solid-gas separation filter disposed inside a container and supported by a support member, and a pulsation wave generating means for converting a fluidized gas introduced into the fluidized bed container into a gas pulsation wave, the filter being a woven fabric a bag filter made of the filter is displaceably supported in the vertical direction by an elastic means relative to the support member, in a state where external force to the filter is not applied, the resilient means downward from the natural state by the weight of the filter elongation by a predetermined distance, the filter is ready with a slack in the vertical direction, the pulsation of gas pulsating introduced into the fluidized bed vessel, filter pairs to a support member By vertically displaced Te, it provides a configuration in which particulate material adhering to the filter is brushed off. Here, the gas pulsation wave refers to a gas flow in which the wind speed (and pressure) changes at a predetermined cycle. The frequency of the gas pulsation wave is preferably 0.5 to 5 Hz. Further, it is preferable to use an elastic means such as a spring or rubber as a support means for supporting the filter with respect to the support member.

  By using a gas pulsating wave as a fluidizing gas, a process using fine particles having a small particle diameter as a raw material (for example, a granulating process using fine particles of 50 μm or less as a raw material, a coating process targeting fine core particles of 150 μm or less), In the granulation process using highly sticky particles such as high content fats and oils as raw materials, it ensures the good fluidity of the powder particles in the fluidized bed container, and the powders with good processing quality The product can be manufactured.

Also, displaceably supported in the vertical direction by the elastic means with respect to the support member filters, the pulsation of gas pulsating introduced into the fluidized bed vessel, by vertically displaced filter with respect to the support member By adopting a configuration in which the powder particles adhering to the filter are removed, the powder particles adhering to the filter can be continuously removed from the filter and returned to the fluidized bed during operation of the fluidized bed apparatus. Therefore, adhesion and retention of the powder particles on the filter is suppressed. As a result, the number of filter removal operations due to shaking or backwashing in the processing step can be reduced, and the processing operation can be simplified and the processing efficiency can be improved. In addition, by suppressing the accumulation and retention of the granular particles on the filter during operation, the dispersion of the component content in the product is suppressed, and the powder that has adhered and stayed on the filter during the shake-off operation by shaking or backwashing Since the granular particles do not fall in the aggregated state and are not returned to the fluidized bed, the quality uniformity such as the component content of the product and the particle size distribution is improved.

Further, in order to solve the above problems, the present invention provides a fluidized bed apparatus that performs at least one of granulation, coating, and drying while floating and flowing a granular material with a fluidized gas in a fluidized bed container. This is a method to wipe off the powder particles adhering to the solid-gas separation filter placed inside the layer container, using a bag filter made of woven cloth as the filter, and moving the filter up and down with elastic means against the support member In a state where the filter is suspended so as to be displaced in the direction and no external force is applied to the filter, the elastic means extends downward from the natural state by a predetermined dimension due to its own weight, and the filter is in a state of slack in the vertical direction. so as to, a fluidizing gas introduced into the fluidized bed vessel was gas pulsating wave, the pulsation of the gas pulsating wave, the vertical direction relative to the support member filters By displacing the provides methods shake off granular material adhering to the filter.

  According to the present invention, it is possible to suppress adhering and staying of the granular particles on the filter during operation of the fluidized bed apparatus, and to reduce the number of shake-out operations by shaking and backwashing in the processing process, thereby simplifying the processing operation. In addition, the processing efficiency can be improved, and the uniformity of quality such as the component content and particle size distribution of the granular product can be improved.

It is a figure which shows typically the example of 1 structure of the fluidized-bed apparatus which concerns on 1st Embodiment. It is a figure which shows the peripheral part of a pulsation wave generator. It is an enlarged view of the periphery of a filter part. It is a figure which shows typically the example of 1 structure of the fluidized-bed apparatus which concerns on 2nd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 schematically shows a configuration example of a fluidized bed apparatus according to the first embodiment.

  The fluidized bed apparatus according to this embodiment includes a fluidized bed container 1 having a ventilation part 1 a at the bottom, an air supply chamber 2 provided at the lower part of the fluidized bed container 1, and an air supply path 3 connected to the air supply chamber 2. A pulsating wave generator 4 as a pulsating wave generating means interposed in the air supply path 3, an exhaust path 5 connected to the upper part of the fluidized bed container 1, and a gas suction means connected to the exhaust path 5 , A bypass path 7 connecting the pulsating wave generator 4 and the exhaust path 5, and a filter unit 8 installed in the upper space in the fluidized bed container 1.

  The ventilation part 1a at the bottom of the fluidized bed container 1 is composed of a gas dispersion plate made of a perforated plate such as punching metal and a mesh, for example. Further, a spray nozzle 9 for spraying a spray liquid, for example, a binder liquid, is installed in a space below the filter unit 8 in the fluidized bed container 1. The space above the filter unit 8 in the fluidized bed container 1 is an exhaust chamber 15.

  The air supply path 3 includes an upstream air supply path 3a upstream of the pulsation wave generator 4 and a downstream downstream air supply path 3b. An air conditioner 9 that adjusts the temperature of gas, for example, air, and an air flow meter 10 that measures the air volume (flow rate) of air are interposed in the upstream air supply path 3a. One end of the upstream air supply path 3a is connected to the inlet 4a (see FIG. 2) of the pulsating wave generator 4, and the other end communicates with the atmosphere via a filter (not shown). An air supply damper 11 is interposed in the downstream air supply path 3b. One end of the downstream air supply path 3 b is connected to the first discharge port 4 b (see FIG. 2) of the pulsating wave generator 4, and the other end is connected to the air supply chamber 2.

  The exhaust path 5 is connected to the exhaust chamber 15 in the fluidized bed container 1, and is connected to the suction blower 6 via the exhaust damper 12 and the dust collector 13.

  One end of the bypass path 7 is connected to the second discharge port 4 c (see FIG. 2) of the pulsating wave generator 4, and the other end is connected to the exhaust path 5 at a position upstream of the exhaust damper 12.

  As shown in FIG. 2, the pulsating wave generator 4 is in sliding contact with a casing 4d having a circular cross section having an inlet 4a, a first outlet 4b, and a second outlet 4c on a peripheral wall, and an inner surface of the peripheral wall of the casing 4d. And a rotating rotary valve 4e. As described above, the upstream supply path 3a is connected to the inlet 4a, the downstream supply path 3b is connected to the first discharge port 4b, and the bypass path 7 is connected to the second discharge port 4c. The rotary valve 4e is rotationally driven by a driving means (not shown).

  By the rotation of the rotary valve 4e, the upstream air supply path 3a communicates only with the downstream air supply path 3b {state of FIG. 2 (a)}, and the upstream air supply path 3a communicates only with the bypass path 7. The state changes gradually and continuously to the state {state of FIG. 2 (b)}. While gradually changing from the state of FIG. 2A to the state of FIG. 2B, the gas flow from the upstream supply passage 3a is gradually distributed from the downstream supply passage 3b to the bypass passage 7. Go. That is, in the state of FIG. 2A, the entire amount of the gas flow from the upstream air supply path 3a flows to the downstream air supply path 3b, but from this state, the upstream side air supply is performed by the rotation of the rotary valve 4e. In a state where a part of the gas flow from the path 3a is gradually distributed and distributed to the bypass path 7, and the rotary valve 4e reaches the position of FIG. The entire amount of the gas flow flows to the bypass path 7. Further, during the gradual change from the state of FIG. 2B to the state of FIG. 2A, the gas flow from the upstream air supply path 3a is gradually changed from the bypass path 7 to the downstream air supply path 3b. It will be distributed. That is, in the state of FIG. 2B, the entire amount of gas flow from the upstream air supply path 3a flows to the bypass path 7, but from this state, the rotation of the rotary valve 4e causes the upstream air supply path 3a to return. In the state where a part of the gas flow is gradually increased and distributed to the downstream air supply path 3b and the rotary valve 4e reaches the position shown in FIG. 2 (a), the flow from the upstream air supply path 3a is increased. The entire amount of the gas flow flows to the downstream air supply path 3b.

  By the operation of the pulsation wave generator 4 as described above, the gas flow from the upstream air supply path 3a flows into the downstream air supply path 3b as a gas pulsation wave accompanied by a periodic air volume change. That is, the wind speed of the gas flowing through the pulsating wave generator 4 to the downstream air supply path 3b is the highest in the state of FIG. 2 (a) and the lowest in the state of FIG. 2 (b). The minimum wind speed appears continuously in a predetermined cycle according to the rotation of the rotary valve 4e. Further, the flow rate of the gas flowing in the downstream side air supply path 3b changes gradually between the maximum wind speed and the minimum wind speed, and the gas from the upstream side air supply path 3a changes according to the change in the wind speed of the gas pulsation wave. A part or all of the flow flows to the bypass path 7 via the pulsating wave generator 4.

  FIG. 3 shows an enlarged view of the periphery of the filter unit 8 of the fluidized bed container 1. In this embodiment, a bag filter 8 a made of a woven fabric filter is used for the filter unit 8. The bag filter 8a is composed of a plurality of tubular (bag-shaped) filter elements 8a1 and a flat surface portion 8a2 connecting lower end openings of the plurality of filter elements 8a1 in order to increase the filtration area. The peripheral edge portion of the flat surface portion 8a2 is held on the wall portion of the fluidized bed container 1 through a seal 8a3.

  The upper end portion of the filter element 8a1 of the bag filter 8a is supported by a support member, in this embodiment via an elastic means 8b (for example, a spring), and in this embodiment, is supported by a support ring 8c. The support ring 8c is connected to an actuator, for example, a fluid pressure cylinder 8d (air cylinder or the like), and moves up and down by the operation of the fluid pressure cylinder 8d. A normal pay-off operation is performed by operating the fluid pressure cylinder 8d. That is, when the fluid pressure cylinder 8d is operated, the support ring 8c is moved in the vertical direction, whereby a shaking operation is given to the bag filter 8a, and the granular material adhering to the surface of the bag filter 8a is wiped off. In this embodiment, the bag filter 8a has a single shaking method, and the operation of the fluidized bed apparatus is stopped when the bag filter 8a is shaken by the fluid pressure cylinder 8d.

  As described above, in this embodiment, the upper end portion of the bag filter 8a (the upper end portion of the filter element 8a1) is suspended and supported by the support ring 8c via the elastic means 8b. When no external force is applied to the bag filter 8a, the elastic means 8b extends by a predetermined dimension from the natural state due to the weight of the bag filter 8a, and the upper end of the bag filter 8a is at the upper limit position (maintaining the proper shape of the bag filter 8a). However, the upper end portion is positioned below a predetermined dimension from the position where the upper end portion can be suspended upward. For this reason, the bag filter 8a is slightly slackened. The upper end portion of the bag filter 8a can be displaced in the vertical direction with respect to the support ring 8c within the range of expansion and contraction of the elastic means 8b from this position, and along with the vertical displacement of the upper end portion with respect to the support ring 8c, the bug A shaking operation is given to the filter 8a.

  In the above configuration, when the suction blower 6 and the pulsating wave generating device 4 are operated, the gas suction force by the suction blower 6 causes the exhaust path 5, the inside of the fluidized bed container 1, the downstream side air supply path 3 b, and the pulsating wave generating apparatus 4. And the upstream air supply path 3a via the exhaust path 5, the bypass path 7, and the pulsating wave generator 4. The function of the pulsation wave generator 4 supplies the gas pulsation wave to the air supply chamber 2 via the upstream air supply path 3a, the pulsation wave generator 4, and the downstream air supply path 3b. For example, the air pulsation wave supplied to the air supply chamber 2 is adjusted to a temperature of 25 to 200 ° C. by the air conditioner 9, and is adjusted to 0.25 to 1.5 m / sec by the air supply damper 11 and the exhaust damper 12. It is adjusted to the average passing wind speed and adjusted to a frequency of 0.5 to 5 Hz by the pulsating wave generator 4.

  The gas pulsation wave supplied to the air supply chamber 2 is ejected into the fluidized bed container 1 through the ventilation portion 1a, and the granular material is suspended and fluidized in the fluidized bed container 1 by the ejection of the gas pulsation wave. A fluidized bed is formed. And a binder liquid is sprayed from the spray nozzle 9 with respect to the fluidized bed of this granular material raw material. The granular raw material that has been sprayed with the binder liquid has a particle diameter that grows due to the bonding of the particles, and is dried by gas pulsation waves to become a granulated product having a predetermined particle diameter.

  On the other hand, part or all of the gas flow from the upstream air supply path 3 a is transferred to the bypass path 7 via the pulsation wave generator 4 in accordance with the change in the wind speed of the gas pulsation wave introduced into the fluidized bed container 1. Therefore, when the communication state between the upstream supply passage 3a and the lower supply passage 3b is blocked or reduced by the pulsation wave generator 4, the fluidized bed container 1 is caused by the gas suction force of the suction blower 6. It is possible to prevent a phenomenon in which an excessive negative pressure acts on the inside of the.

  The gas pulsation wave introduced into the fluidized bed container 1 contributes to the fluidized bed formation and drying of the granular material, and then passes through the bag filter 8a and flows out to the exhaust path 5. At that time, the fine powder mixed in the upward flow of the gas pulsation wave is captured by the bag filter 8a. Further, the bag filter 8a receives an upward force due to the wind pressure of the gas pulsating wave rising in the fluidized bed container 1, and its upper end is displaced upward within the range of contraction displacement of the elastic means 8b. Thereby, the bag filter 8a suspended and supported with the support ring 8c slightly slackened is pulled upward to be in a tension state. On the other hand, when the wind pressure of the gas pulsation wave acting on the bag filter 8a disappears or becomes smaller than a predetermined value, the upper end of the bag filter 8a is displaced downward, and the bag filter 8a returns to a slightly slack state. In this manner, the bag filter 8a periodically repeats the slack state and the tension state by the pulsation of the gas pulsation wave introduced into the fluidized bed container 1, and adheres to the surface of the bag filter 8a by this periodic repetition operation. The fine powder is removed and returned to the lower fluidized bed.

  FIG. 4 schematically shows a configuration example of the fluidized bed apparatus according to the second embodiment. In this embodiment, the upstream air supply path 3a and the exhaust path 5 are connected by a bypass path 7 '. An exhaust damper 13 is interposed in the bypass path 7 '. Further, the pulsating wave generator 4 ′ includes a casing and a rotary valve similar to the pulsating wave generator 4 in the first embodiment, but unlike the pulsating wave generator 4, the casing has an upstream side. An inlet connected to the air supply path 3a and a discharge port 4b connected to the downstream air supply path 3b are provided. The rotation of the rotary valve 4e causes the upstream air supply path 3a to pass through the downstream air supply path. It operates so as to intermittently communicate with 3b. The bag filter 8a is suspended and supported by the support ring 8c via the elastic means 8bb as in the first embodiment.

  When the suction blower 6 and the pulsating wave generating device 4 ′ are operated, the gas suction force by the suction blower 6 passes through the exhaust path 5, the inside of the fluidized bed container 1, the downstream air supply path 3b, and the pulsating wave generating apparatus 4 ′. And the upstream air supply path 3a via the exhaust path 5 and the bypass path 7 '. And, by the function of the pulsation wave generator 4 ′, a gas pulsation wave is supplied to the air supply chamber 2 via the upstream air supply path 3a, the pulsation wave generator 4 ′, and the downstream air supply path 3b, Part or all of the gas flows from the upstream air supply path 3a to the exhaust path 5 via the bypass path 7 '. When the communication between the upstream air supply path 3a and the downstream air supply path 3b is blocked by the pulsation wave generator 4 ', all of the gas from the upstream air supply path 3a is exhausted via the bypass path 7'. Flows along path 5. Since other matters are the same as those in the first embodiment, a duplicate description is omitted.

  In the above embodiment, the single shaking method is adopted as the bag filter pay-off mechanism, but a twin shaking method may be used.

  In the above embodiment, the elastic means 8b is used as the support means for supporting the bag filter 8a on the support ring 8c. However, the support means is not limited to the elastic means, and the vertical displacement of the upper end portion of the bag filter is predetermined. Any material that is acceptable within the range is acceptable. For example, a telescopic member or a slide member may be used as the support means.

  Furthermore, in the above embodiment, a mechanism for generating a gas pulsation wave by the operation of the pulsation wave generation means 4 and the suction blower 6 is employed. It is good also as a mechanism which supplies the gas flow from an apparatus to the pulsation wave generation means 4, and generates a gas pulsation wave.

DESCRIPTION OF SYMBOLS 1 Fluidized bed container 4, 4 'Pulsating wave generator 8 Filter part 8a Bag filter 8b Elastic means 8c Support ring

Claims (2)

In a fluidized bed apparatus that performs at least one of granulation, coating, and drying while suspending and flowing a granular material with a fluidized gas in a fluidized bed container,
A solid-gas separation filter disposed inside the fluidized bed container and supported by a support member; and a pulsating wave generating means for converting the fluidized gas introduced into the fluidized bed container into a gas pulsating wave,
The filter is a bag filter made of woven cloth, and the filter is suspended and supported by the support member so as to be vertically displaceable by an elastic means , and the elastic means is in a state where no external force is applied to the filter. Is extended by a predetermined dimension downward from the natural state due to the weight of the filter, the filter is slackened in the vertical direction, and the pulsation of the gas pulsation wave introduced into the fluidized bed container causes the filter to A fluidized bed apparatus characterized in that the granular material adhering to the filter is removed by displacing in a vertical direction with respect to the support member. In a fluidized bed apparatus that performs at least one of granulation, coating, and drying while suspending and flowing a granular material with a fluidized gas in a fluidized bed container, the solid-gas separation disposed inside the fluidized bed container A method of removing particles adhering to a filter for use,
A bag filter made of woven cloth is used as the filter , the filter is suspended and supported by an elastic means in a vertical direction with respect to a support member, and in the state where no external force is acting on the filter, the elastic means is Due to the weight of the filter, the filter extends by a predetermined dimension downward from the natural state, the filter is slackened in the vertical direction, the fluidized gas introduced into the fluidized bed container is a gas pulsation wave, A method for removing a filter in a fluidized bed apparatus, wherein the particulate matter adhering to the filter is removed by displacing the filter in a vertical direction with respect to the support member by pulsation of a gas pulsation wave.

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