JP2015160764A - Heating regeneration treatment apparatus and treatment method for waste gypsum - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heating regeneration treatment apparatus for waste gypsum which is capable of a heating regeneration treatment to obtain both hemihydrate gypsum and II-type anhydrous gypsum appropriately from waste gypsum in a state of dihydrate gypsum state.SOLUTION: In a heating regeneration treatment apparatus for waste gypsum, a kiln 2 for anhydrous gypsum regeneration which heat-treats waste gypsum to regenerate to II-type anhydrous gypsum and a kiln 3 for hemihydrate gypsum regeneration which regenerates to hemihydrate gypsum are arranged in series and connected together. The kiln 2 for anhydrous gypsum regeneration is provided with a burner 12 for supply of hot air and a hemihydrate gypsum charge part 13 in one end part and with an anhydrous gypsum discharge part 14 in the other end part, and the kiln 3 for hemihydrate gypsum regeneration is provided with a waste gypsum charge part 15 in one end part and with the hemihydrate gypsum discharge part 17 in the other end. On the lower side of the hemihydrate gypsum discharge part 17, there are provided dampers 36 and 37 serving as discharge destination switching means capable of switching the discharge destination between a storage bottle and the hemihydrate gypsum charge part 13 of the kiln 2 for anhydrous gypsum generation.

Description

  The present invention is a heat regeneration treatment of waste gypsum which is regenerated as anhydrous gypsum or hemihydrate gypsum by heat treatment of waste gypsum in the state of dihydrate gypsum obtained by crushing and separating waste gypsum board which is building waste material Relates to the device.

  Conventionally, most of the waste gypsum board that is generated in large quantities due to the dismantling of buildings has been disposed of by landfill, etc., but the waste gypsum board is managed from stable industrial waste by the revision of the Waste Disposal Law. From the viewpoints of soaring treatment costs due to the shift to industrial waste, lack of landfill sites, and effective use of resources, it is desirable to separate and recover gypsum from waste gypsum board .

By the way, gypsum is roughly classified into three types, dihydrate gypsum (CaSO ₄ · 2H ₂ O), hemihydrate gypsum (CaSO ₄ · 1 / 2H ₂ O), and anhydrous gypsum (CaSO ₄ ), depending on the difference in crystal water. It has been found that when dihydrate gypsum is heated to about 130 to 180 ° C., it is rearranged to hemihydrate gypsum, and further heated to about 350 to 800 ° C., it is rearranged to type II anhydrous gypsum. In addition, when hydration treatment is performed on hemihydrate gypsum, the hydration reaction proceeds quickly, and it is transferred to dihydrate gypsum and hardens in a short time. Type II anhydrous gypsum that cures slowly has the potential to be reused, for example, as a raw material for cement.

  Gypsum such as gypsum board is in the form of dihydrate gypsum, and even if it is subjected to water treatment, hydration reaction will not occur and it will not harden, but heat treatment will cause hemihydrate gypsum and type II anhydrous gypsum It is considered that the applications of reuse as described above will be expanded if it is rearranged, for example, the present applicant also disclosed in Patent Document 1 (Patent No. 5081379) and Patent Document 2 (Patent No. 5081396). As shown in the figure, the collected waste gypsum is put into a rotary kiln with a plurality of scraping blades around the inner periphery, and exposed to the hot air from the burner while rolling down the kiln. A reprocessing device that regenerates as hemihydrate gypsum is proposed.

Japanese Patent No. 5081379 Japanese Patent No. 5081396

  By the way, each of the above conventional devices is a device that regenerates waste gypsum in the form of dihydrate gypsum exclusively as hemihydrate gypsum, but if it becomes a combined device that can regenerate both hemihydrate gypsum and type II anhydrous gypsum Any one of them can be selectively reproduced according to demand, and the apparatus becomes more convenient. However, there is a big difference between the temperature at which dihydrate gypsum rearranges into hemihydrate gypsum and the temperature at which it rearranges into type II anhydrous gypsum. Necessary. For example, in the above-mentioned conventional apparatus, a number of scraping blades are provided in the kiln in order to increase the heating efficiency, but if it is to be regenerated to type II anhydrous gypsum, a heat treatment at a relatively high temperature is required. Further, protection with a heat-resistant caster or the like is essential instead of the scraping blade, and there is a concern that the heating efficiency is lowered and the energy loss is increased.

  In view of the above points, the present invention is to provide a heat regeneration treatment apparatus for waste gypsum that can appropriately heat and regenerate both hemihydrate gypsum and type II anhydrous gypsum from waste gypsum in the form of dihydrate gypsum. And

  In order to solve the above-mentioned problems, the waste gypsum heat regeneration treatment apparatus according to claim 1 according to the present invention heat-treats waste gypsum in the state of dihydrate gypsum obtained by crushing and separating waste gypsum board. Recycled waste gypsum heat regeneration equipment that regenerates as type II anhydrous gypsum or hemihydrate gypsum, and recycles it into hemihydrate gypsum, which is an anhydrous gypsum regeneration kiln that heats waste gypsum to regenerate into type II anhydrous gypsum. A half-water gypsum recycle kiln is connected in series, and one end of the anhydrous gypsum recycle kiln has a burner for supplying hot air and a half-water gypsum throw-in portion for feeding half-water gypsum at the other end. Each part is equipped with a heat-treated type II anhydrous gypsum discharging gypsum discharging part, while one end of the hemihydrate gypsum recycling kiln has a waste gypsum charging part for the other gypsum, Equipped with a semi-water gypsum discharge section for discharging heat-treated half-water gypsum In addition, at the lower part of the hemihydrate gypsum discharge section, the discharge destination switching that can switch the discharge destination of the hemihydrate gypsum to either a storage bin for storing hemihydrate gypsum or a half water gypsum input section of a kiln for regenerating anhydrous gypsum It is characterized by having means.

  In the heat treatment apparatus for waste gypsum according to claim 2, a heat-resistant caster is provided around the inner periphery of the anhydrous gypsum regeneration kiln, while It is characterized by a plurality of scraping blades.

  The waste gypsum heat regeneration processing apparatus according to claim 3, wherein a discharge destination of gypsum fine particles collected by a dust collector provided downstream of the exhaust duct of the half water gypsum regeneration kiln is used for storing the half water gypsum. Discharge destination switching means that can be switched to either a storage bottle or a half-water gypsum charging part of an anhydrous gypsum regeneration kiln is provided.

  Further, in the method for heat regeneration treatment of waste gypsum according to claim 4, type II anhydrous gypsum or hemihydrate gypsum is obtained by heat treating waste gypsum in the form of dihydrate gypsum obtained by crushing and separating waste gypsum board. A waste gypsum heat regeneration treatment method that recycles waste gypsum into a type II anhydrous gypsum and an anhydrous gypsum recycle kiln that regenerates into half water gypsum in series. In addition, the one end of the anhydrous gypsum regeneration kiln is equipped with a hot air supply burner, and when the waste gypsum is regenerated into semi-water gypsum, the temperature in the semi-water gypsum recycle kiln is While controlling the burner combustion amount so that it is maintained at a temperature at which it is rearranged into hemihydrate gypsum, waste gypsum is put into a hemihydrate gypsum kiln and heat treated to recover it as hemihydrate gypsum. When regenerating to type anhydrous gypsum, While controlling the burner combustion amount so that the temperature in the raw kiln is maintained at the temperature at which the waste gypsum is rearranged into type II anhydrous gypsum, the waste gypsum is put into the semi-water gypsum kiln and preheated, It is characterized by being put into an anhydrous gypsum regeneration kiln and heat treated to recover as type II anhydrous gypsum.

  According to the waste gypsum heat regeneration treatment apparatus according to claim 1 of the present invention, an anhydrous gypsum regeneration kiln that regenerates waste gypsum to regenerate it into type II anhydrous gypsum, and hemihydrate gypsum that regenerates to hemihydrate gypsum. A regeneration kiln is arranged and connected in series, and one end of the anhydrous gypsum regeneration kiln is provided with a hot air supply burner and a half-water gypsum input part, and the other end is provided with an anhydrous gypsum discharge part. On the other hand, one end of the hemihydrate gypsum regeneration kiln is provided with a waste gypsum charging portion, and the other end is provided with a half water gypsum discharge portion. Discharge destination switching means that can be switched to either a storage bottle or a half-water gypsum input part of an anhydrous gypsum-regenerating kiln, so when reusing waste gypsum to semi-water gypsum Where it is recovered by heating in a kiln and reclaimed into type II anhydrous gypsum In this case, the heat treated with a hemihydrate gypsum recycle kiln can be collected in the anhydrous gypsum recycle kiln and reheated to recover as type II anhydrous gypsum. And can be played back, making it easy to use. In addition, when regenerating Type II anhydrous gypsum, high-temperature exhaust gas derived from the anhydrous gypsum recycling kiln can be introduced into the hemihydrate gypsum recycling kiln, which can be used for pre-heat treatment of waste gypsum. It becomes possible.

  According to the waste gypsum heat regeneration treatment apparatus according to claim 2, a heat-resistant caster is provided around the inner peripheral portion of the anhydrous gypsum regeneration kiln, while the inner peripheral portion of the hemihydrate gypsum regeneration kiln. Since there are a number of scraping blades around, it is possible to handle heat treatment at high temperatures when regenerating type II anhydrous gypsum, but in a semi-water gypsum recycling kiln with scraping blades, exhaust gas heat The heat treatment can be efficiently performed while effectively utilizing the energy loss, and the energy loss can be suppressed.

  In addition, according to the waste gypsum heat regeneration processing apparatus according to claim 3, the discharge destination of gypsum fine particles collected by the dust collector downstream of the exhaust duct is used as a storage bin for storing semi-water gypsum, or for regenerating anhydrous gypsum. Because it is equipped with a destination switching means that can be switched to any one of the half water gypsum input parts of the kiln, the gypsum fine particles collected by the dust collector can be appropriately treated and recovered as hemihydrate gypsum or type II anhydrous gypsum, It becomes possible to improve the yield of the gypsum to regenerate.

  Further, according to the method for heat regeneration treatment of waste gypsum according to claim 4, the kiln for reclaiming anhydrous gypsum which heat-treats waste gypsum to regenerate to type II anhydrous gypsum, and the recycle for hemihydrate gypsum regenerated to hemihydrate gypsum. A kiln and a kiln are arranged and connected in series, and one end of the anhydrous gypsum recycling kiln is provided with a hot air supply burner, and when regenerating waste gypsum into semi-water gypsum, While controlling the burner combustion amount so that the temperature is maintained at the temperature at which the waste gypsum is transferred to hemihydrate gypsum, the waste gypsum is put into a hemihydrate gypsum kiln and heat treated to recover it as hemihydrate gypsum, When reclaiming waste gypsum to type II anhydrous gypsum, while controlling the burner combustion amount so that the temperature in the anhydrous gypsum regeneration kiln is maintained at the temperature at which waste gypsum is transferred to type II anhydrous gypsum, Preheated by putting in a water gypsum kiln Since it was put into an anhydrous gypsum recycle kiln and heat treated to recover as type II anhydrous gypsum, waste gypsum can be appropriately recycled into hemihydrate gypsum and type II anhydrous gypsum according to demand, making it easy to use It will be a thing. Further, when regenerating type II anhydrous gypsum, high-temperature exhaust gas derived from the anhydrous gypsum regeneration kiln can be used for pre-heat treatment in the hemihydrate gypsum regeneration kiln, so that energy can be effectively utilized.

It is a schematic explanatory drawing which shows one Example of the heat reproduction processing apparatus and processing method of waste gypsum concerning this invention.

  In the waste gypsum heat regeneration treatment apparatus and treatment method according to the present invention, the anhydrous gypsum regeneration kiln for regenerating waste gypsum by heat treatment to regenerate to type II anhydrous gypsum, and hemihydrate gypsum regeneration for regenerating to half water gypsum The kiln for recycling is connected in series, and heat-resistant casters are provided around the inner circumference of the anhydrous gypsum recycling kiln, while there are several There is a scraping blade around. In addition, one end of the anhydrous gypsum regeneration kiln is equipped with a hot air supply burner and a half-water gypsum charging section, and the other end is equipped with a heat-treated type II anhydrous gypsum discharging gypsum discharging section. On the other hand, one end of the half water gypsum regeneration kiln is provided with a waste gypsum charging portion, and the other end is provided with a heat treated half water gypsum discharge portion.

  In addition, in the lower half of the half-water gypsum discharge section of the hemihydrate gypsum recycle kiln, a storage bottle for storing a half-water gypsum with a discharge destination of the heat-treated half-water gypsum nearby, or a half of the anhydrous gypsum recycle kiln While equipped with a destination switching means that can be switched to any one of the water gypsum input parts, the gypsum fine particles collected by the dust collector are also provided below the dust collector provided downstream of the exhaust duct of the half water gypsum regeneration kiln. A discharge destination switching means capable of switching the discharge destination to either the storage bin for storing hemihydrate gypsum or the half water gypsum charging portion of the anhydrous gypsum regeneration kiln.

  And when the waste gypsum in the state of dihydrate gypsum obtained by crushing and separating waste gypsum board using the apparatus configured as described above is heat-treated and regenerated into semi-water gypsum, the hot air downstream side of the burner While controlling the burner combustion amount so that the temperature in the kiln for reclaiming gypsum located at a temperature where the gypsum is transferred to hemihydrate gypsum, for example, about 130 to 180 ° C., is controlled. It is put into a water plaster recycling kiln. The waste gypsum introduced into the semi-water gypsum kiln is efficiently heated by being exposed to the hot air supplied from the burner while rolling down the kiln while being scraped up by a plurality of scraping blades. Collected as gypsum. The gypsum fine particles collected by the dust collector downstream of the exhaust duct are also heated to a temperature at which they are transferred to hemihydrate gypsum by airflow drying, and can be collected together with the hemihydrate gypsum discharged from the kiln. it can.

  On the other hand, when reclaiming waste gypsum by heat treatment to regenerate type II anhydrous gypsum, the temperature in the anhydrous gypsum regeneration kiln located upstream of the hot air of the burner is the temperature at which the waste gypsum rearranges to type II anhydrous gypsum, for example, about 350 The waste gypsum is first charged into the hemihydrate gypsum kiln on the downstream side of the hot air while controlling the burner combustion amount so as to be maintained at about ˜800 ° C. As described above, the waste gypsum introduced into the hemihydrate gypsum recycle kiln is preheated by hot air from the burner while rolling down in the kiln while being scraped up by a plurality of scraping blades, Discharged in a state. The heat treatment in the kiln for regenerating the gypsum is for the purpose of preheating and drying gypsum, and it is not always necessary to be in the state of gypsum at the time of discharge. Dihydrate gypsum and anhydrous gypsum are mixed. There is no problem even if it is.

  Next, by operating the discharge destination switching means below the half water gypsum discharge part of the half water gypsum regeneration kiln, the half water gypsum discharged from the kiln is transferred to the upstream side of the hot air via a conveying means such as an air pressure feeder. Put in anhydrous gypsum kiln. The hemihydrate gypsum thrown into the anhydrous gypsum recycle kiln flows down without being scraped up on a heat-resistant caster around the inner periphery of the kiln, while being exposed to high-temperature hot air supplied from the nearest burner. It is heat treated and recovered as type II anhydrous gypsum.

  At this time, since the gypsum put into the anhydrous gypsum regeneration kiln has been preheated and dried to some extent in the hemihydrate gypsum regeneration kiln, it is efficient to regenerate to type II anhydrous gypsum requiring heat treatment at a relatively high temperature. Can be done well. In addition, the gypsum fine particles collected by the dust collector downstream of the exhaust duct contain a large amount of gypsum in the form of almost half water gypsum that is scattered by the pre-heat treatment in the kiln for reclaiming gypsum with scraped blades. However, by appropriately operating the discharge destination switching means provided in the lower part of the dust collector, the collected gypsum fine particles are introduced into the anhydrous gypsum recycling kiln via the conveying means such as an air pressure feeding device, etc. It can be recovered as type II anhydrous gypsum by heat treatment with hemihydrate gypsum supplied from the kiln.

  In this way, according to this device, waste gypsum in the form of dihydrate gypsum can be selectively recycled to either hemihydrate gypsum or type II anhydrous gypsum according to demand, making it easy to use It becomes. Also, heat-resistant casters should be installed around the inner periphery of the anhydrous gypsum regeneration kiln on the upstream side of the hot air, and a plurality of scraping blades should be installed around the inner periphery of the half-water gypsum regeneration kiln on the downstream side of the hot air. Therefore, while being able to cope with the regeneration of type II anhydrous gypsum that requires heat treatment at high temperature, the derived high-temperature exhaust gas heat can be effectively and efficiently used for preheating and drying treatment. Furthermore, the gypsum fine particles collected by the dust collector can be appropriately treated and recovered as hemihydrate gypsum or type II anhydrous gypsum, and the yield of reclaimed gypsum can be improved.

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

  In the figure, reference numeral 1 denotes a heat regeneration processing apparatus for heat recycling treatment of waste gypsum in the form of dihydrate gypsum obtained by crushing and separating waste gypsum board. Type II anhydrous gypsum by heat treatment of waste gypsum The anhydrous gypsum recycling kiln 2 to be regenerated and the half water gypsum recycling kiln 3 to be regenerated to half water gypsum are arranged in series and connected via an intermediate hopper 4 as shown in the figure.

  The anhydrous gypsum regeneration kiln 2 is a rotary kiln in which a cylindrical drum 6 inclinedly supported on a machine base 5 is rotationally driven at a predetermined speed by a driving motor (not shown). A heat-resistant caster 7 such as refractory bricks and ceramics is provided around the periphery to protect it, while a semi-water gypsum kiln 3 is similarly supported by a cylindrical drum 9 inclined and supported on a machine base 8. The rotary kiln is driven to rotate at a predetermined speed by a drive motor (not shown), and a number of scraping blades 10 are provided around the inner peripheral portion to increase the heating efficiency.

  The hot hopper 11 disposed at one end (on the upstream side of hot air) of the anhydrous gypsum regeneration kiln 2 is provided with a burner 12 for supplying hot air and a half-water gypsum charging portion 13 for charging half-water gypsum. On the other hand, the lower end portion of the intermediate hopper 4 at the other end portion (on the downstream side of the hot air) is provided with a heat-treated type II anhydrous gypsum discharging portion 14 for discharging anhydrous gypsum. Further, an upper end portion of the intermediate hopper 4 positioned at one end portion (hot air upstream side) of the half water gypsum regeneration kiln 3 is provided with a waste gypsum throwing portion 15 for throwing out waste gypsum, while the other end portion (hot air downstream). At the lower end of the cold hopper 16 disposed on the side), a heat-treated hemihydrate gypsum discharge portion 17 for discharging the hemihydrate gypsum is provided.

  An exhaust duct 18 for exhaust gas exhaust is connected to the upper end portion of the cold hopper 16, and a cooling device 19 for cooling the high temperature exhaust gas derived from the kiln or a bug that is a dust collector is disposed downstream of the exhaust duct 18. A filter 20, a main damper 21 for adjusting the amount of exhaust air, an air exhauster 22, and a chimney 23 are provided. The cooling device 19 may be operated / stopped according to the exhaust gas temperature. For example, as in the exhaust gas temperature (about 130 to 180 ° C.) when regenerating the hemihydrate gypsum, it is directly downstream. While it is stopped to the extent that there is no problem even if it is sent to the bag filter 20, it is sent to the downstream bag filter 20 as it is, such as the exhaust gas temperature (about 350 to 800 ° C.) when regenerating the anhydrous gypsum. When there is a risk of burning, it is recommended to operate and perform the cooling process.

  Further, a temperature sensor 24 for detecting the temperature of the exhaust gas derived from the hemihydrate gypsum regeneration kiln 3 is provided near the base end portion of the exhaust duct 18, and the intermediate hopper 4 is derived from the anhydrous gypsum regeneration kiln 2. A temperature sensor 25 for detecting the temperature of the exhaust gas is provided. Reference numeral 26 denotes a burner combustion controller that takes in the exhaust gas temperatures detected by the temperature sensors 24 and 25, and controls the burner 12 combustion amount based on the difference value amount compared with a preset exhaust gas temperature set value. In the case of reprocessing the hemihydrate gypsum, the exhaust gas temperature is set to a temperature at which the waste gypsum in the dihydrate gypsum state is efficiently transferred to the hemihydrate gypsum, that is, about 130 to 180 ° C. When the burner 12 combustion amount is controlled so that the exhaust gas temperature detected by the temperature sensor 24 provided in the above is maintained at the set temperature, when regenerating the type II anhydrous gypsum, the exhaust gas temperature is changed to hemihydrate gypsum. Is set to about 350 to 800 ° C., and the exhaust gas temperature detected by the temperature sensor 25 provided in the intermediate hopper 4 is maintained at the set temperature. 12 Combustion amount is controlled.

  In the above embodiment, the burner 12 combustion amount is controlled based on the exhaust gas temperature. However, the present invention is not necessarily limited to this. For example, the cold hopper 16 on the downstream side of the hemihydrate gypsum regeneration kiln 3 is used. Temperature of hemihydrate gypsum discharged from the hemihydrate gypsum discharge section 17 at the lower end, and temperature of type II anhydrous gypsum discharged from the anhydrous gypsum discharge section 14 at the lower end of the intermediate hopper 4 downstream of the anhydrous gypsum regeneration kiln 2 May be detected, and the burner 12 combustion amount may be controlled based on these temperatures.

  A static pressure sensor 27 for detecting the static pressure inside the kiln is provided at the corner of the hot hopper 11 at one end of the anhydrous gypsum regeneration kiln 2. 28 is a static pressure / variable control for adjusting the amount of exhaust air by adjusting the opening of the main damper 21 of the exhaust duct 18 (or the rotational speed of the exhaust fan 22) based on the static pressure value detected by the static pressure sensor 27. This is an exhaust air volume controller that controls the exhaust air volume so that the static pressure inside the kiln is almost the same as or slightly negative with respect to the outside air pressure, preventing ejection from the gaps at the ends of each kiln. At the same time, the intrusion of outside air is suppressed to improve energy saving.

  Further, a rotary valve 29 is provided below the anhydrous gypsum discharge portion 14 at the lower end of the intermediate hopper 4, and type II anhydrous gypsum discharged from the rotary valve 29 is supplied to an air pipe 31 by an air pressure feeder 30 below the rotary valve 29. It can be conveyed to a storage bin (not shown) for storing type II anhydrous gypsum provided in the vicinity, while a rotary valve 32 is also provided below the semi-water gypsum discharge part 17 at the lower end of the cold hopper 16. A storage bin (not shown) for storing hemihydrate gypsum provided in the vicinity thereof via an air pipe 34 in the lower air pressure feeding device 33. It can be transported to any one of the half-water gypsum charging portions 13 of the anhydrous gypsum regeneration kiln 2 through an air pipe 35 branched from the air pipe 34.

  Reference numerals 36 and 37 denote the discharge destination of the semi-water gypsum discharged from the semi-water gypsum discharge unit 17 or the air pipe 34 side (half-water gypsum storage bottle side) or the air pipe 35 side (half-water of the anhydrous gypsum regeneration kiln 2). Damper of the discharge destination switching means for switching to the gypsum charging unit 13 side), and the dampers 36 and 37 are provided in the vicinity of the branch portions of the air pipes 34 and 35, respectively. When transporting to the side (half-water gypsum storage bin side), the damper 36 is opened and the damper 37 is closed, and the air-pressure feeding device 33 is used to pump the half-water gypsum, while the half-water gypsum is fed to the air pipe 35 side (anhydrous gypsum). When transporting to the hemihydrate gypsum charging unit 13 side of the regeneration kiln 2, the damper 36 is closed and the damper 37 is opened, and then the air is fed by the air pressure feeding device 33.

  A cyclone-type recovery machine 38 is provided at the terminal end of the air pipe 35, and hemihydrate gypsum is collected from the conveyed product conveyed by air pressure feeding, and the lower rotary valve 39 returns to the hemihydrate gypsum input unit 13. A fixed amount can be supplied. Note that the air after the hemihydrate gypsum has been collected by the collection machine 38 may be merged into the exhaust duct 18 in front of the bag filter 20, for example.

  Further, the gypsum fine particles collected by the bag filter 20 are sequentially sent out by a screw conveyor 40, discharged from a rotary valve 41 provided at the lower part of the terminal portion, and air piping 43 by a lower air pressure feeding device 42. It can be conveyed to either the semi-water gypsum storage bin of the anhydrous gypsum regeneration kiln 2 via the semi-water gypsum storage bin or the air pipe 44 branched from the air pipe 43. The gypsum fine particles collected by the bag filter 20 are mainly fine particles that rise with the scraping blades 10 of the semi-water gypsum regenerating kiln 3, but the gypsum fine particles are collected into the semi-hydrate gypsum by airflow drying. It is heated to the dislocation temperature, and can be handled in substantially the same manner as the half-water gypsum recovered from the half-water gypsum discharge part 17 of the half-water gypsum regeneration kiln 3.

  45 and 46, the discharge destination of the gypsum fine particles (half-water gypsum) discharged from the screw conveyor 40 is the air pipe 43 side (half-water gypsum storage bottle side) or the air pipe 44 side (anhydrous gypsum recycling kiln 2). Damper of the discharge destination switching means for switching to the hemihydrate gypsum charging unit 13 side), and the dampers 45 and 46 are provided in the vicinity of the branch portions of the air pipes 43 and 44, respectively, in the same manner as described above. When the gypsum fine particles (half-water gypsum) are transported to the air pipe 43 side (half-water gypsum storage bottle side), the damper 45 is opened and the damper 46 is closed, and the pressure is fed by the air pressure feeding device 42. When the gypsum fine particles (half water gypsum) are transported to the air pipe 44 side (the half water gypsum charging part 13 side of the anhydrous gypsum regenerating kiln 2), the damper 45 is closed and the damper 46 is opened. Air pressure feeder 2 to be pumped in.

  When the waste gypsum in the dihydrate gypsum state is heat-treated and regenerated into half-water gypsum using the apparatus having the above-described configuration, the waste gypsum efficiently sets the exhaust gas temperature setting value of the burner combustion controller 26 to the half-water gypsum. The temperature is set to, for example, 130 to 180 ° C., which is a temperature at which the gypsum is transferred to the gypsum, and is detected by the temperature sensor 24 provided in the exhaust duct 18 on the downstream side of the half water gypsum regeneration kiln 3 as the control exhaust gas temperature. Take in the exhaust gas temperature. The hot air from the burner 12 passes through the upstream anhydrous gypsum regeneration kiln 2 and is sent to the downstream half water gypsum regeneration kiln 3, while the waste gypsum is supplied from the waste gypsum charging unit 15 provided in the intermediate hopper 4. It puts in the kiln 3 for hemihydrate gypsum regeneration. The waste gypsum introduced into the kiln 3 for regenerating the semi-water gypsum is tumbled down in the kiln while being scooped up by a number of scooping blades 10 provided in the inner periphery of the kiln, and controlled to the above temperature range. It is exposed to hot air from the water and efficiently heat-treated, is regenerated into hemihydrate gypsum, and is sequentially discharged from the hemihydrate gypsum discharge section 17. Then, the damper 36 which is the lower discharge destination switching means of the hemihydrate gypsum discharge section 17 is opened and the damper 37 is closed, and then the air pressure feeding device 33 is operated, and the hemihydrate gypsum discharged from the hemihydrate gypsum discharge section 17. Is transported and stored in a semi-water gypsum storage bottle provided nearby.

  Also, the gypsum fine particles that rise when they are scraped up by the scraping blades 10 flow down to the exhaust duct 18 along with the exhaust gas, and are collected by the bag filter 20 downstream of the exhaust duct 18. At this time, the collected gypsum fine particles are heated to about the temperature at which they are transferred to hemihydrate gypsum by airflow drying, and can be handled almost the same as the hemihydrate gypsum discharged from the kiln 3 for regenerating gypsum, and a screw conveyor. 40. The damper 45, which is a lower discharge destination switching means, is opened and the damper 46 is closed, and then the air pressure feeding device 42 is operated. The collected gypsum fine particles (half-water gypsum) are also collected together with the half-water gypsum storage bottle. To be transported and stored.

  On the other hand, when waste gypsum is heat-treated to regenerate to type II anhydrous gypsum, the exhaust gas temperature set value of the burner combustion controller 26 is a temperature at which the waste gypsum is efficiently transferred to type II anhydrous gypsum, for example, 350 to 800 ° C. In addition, the exhaust gas temperature detected by the temperature sensor 25 provided in the intermediate hopper 4 downstream of the anhydrous gypsum regeneration kiln 2 is taken in as the exhaust gas temperature serving as a reference for control. Then, while the hot air from the burner 12 is sequentially sent to the upstream anhydrous gypsum regeneration kiln 2 and the downstream half water gypsum regeneration kiln 3, the intermediate hopper 4 is first used in the same manner as when regenerating the half water gypsum. Waste gypsum is fed into the kiln 3 for regenerating gypsum from the waste gypsum throwing section 15 provided for the above. The waste gypsum thrown into the kiln 3 for regenerating the half water gypsum is exposed to the hot air from the burner 12 while being tumbled down while being swung up by a large number of scraping blades 10, and is effectively heat-treated. It is regenerated and discharged sequentially from the hemihydrate gypsum discharge part 17.

  At this time, the hot air (exhaust gas) temperature is based on the temperature inside the anhydrous gypsum regeneration kiln 2, and the exhaust gas at a temperature slightly lower than the set temperature is supplied into the downstream half water gypsum regeneration kiln 3. However, it can be used effectively as a preheating / drying treatment when reclaiming waste gypsum to type II anhydrous gypsum. The gypsum discharged from the hemihydrate gypsum discharge unit 17 is processed for the purpose of preheating and drying as described above, and is not necessarily regenerated into hemihydrate gypsum, such as dihydrate gypsum and anhydrous gypsum. There is no problem even if there is a mixed state.

  Next, the damper 36 which is the lower discharge destination switching means of the hemihydrate gypsum discharge part 17 is closed and the damper 37 is opened, and then the air pressure feeding device 33 is operated, and the half water discharged from the hemihydrate gypsum discharge part 17 The gypsum is conveyed to the upstream anhydrous gypsum recycling kiln 2, and the hemihydrate gypsum separated and recovered by the recovery machine 38 is input into the anhydrous gypsum recycling kiln 2 from the lower half water gypsum charging unit 13. The hemihydrate gypsum thrown into the anhydrous gypsum regeneration kiln 2 flows down on the heat-resistant caster 7 provided around the inner periphery of the kiln without being scraped, and the hot hot air supplied from the latest burner 12 The heat-treated caster 7 heat-processes, regenerates to type II anhydrous gypsum, and sequentially discharges from the anhydrous gypsum discharge unit 14. At this time, the gypsum charged into the anhydrous gypsum regeneration kiln 2 has been preheated and dried to some extent in the half water gypsum regeneration kiln 3, so that it can be applied to type II anhydrous gypsum that requires heat treatment at a relatively high temperature. Regeneration can be performed efficiently. Then, the air pressure feeding device 30 is operated, and the type II anhydrous gypsum discharged from the anhydrous gypsum discharging unit 14 is conveyed and stored in a type II anhydrous gypsum storage bottle provided nearby.

  It should be noted that the gypsum fine particles collected by the bag filter 20 downstream of the exhaust duct 18 are semi-water having a scraping blade 10 rather than gypsum scattered from the anhydrous gypsum recycling kiln 2 that does not have a scraping blade. Since a large amount of gypsum in the state of substantially semi-water gypsum that is scattered with the preheating / drying process in the kiln 3 for regenerating gypsum is contained, the damper 45 that is the discharge destination switching means below the screw conveyor 40 is closed and the damper 46 is closed. The air pressure feeding device 42 is operated after being opened, transported to the half-water gypsum charging part 13 of the anhydrous gypsum regeneration kiln 2, and heat-treated again with the half-water gypsum transported from the half-water gypsum regeneration kiln 3. Is regenerated into type II anhydrous gypsum and transported and stored in the type II anhydrous gypsum storage bottle.

  In this embodiment, the anhydrous gypsum regeneration kiln 2 and the semi-water gypsum regeneration kiln 3 employ a cocurrent heating type kiln in which the hot air from the burner 12 and the gypsum supply direction are the same. However, it is also possible to employ a so-called countercurrent heating kiln in which hot air and gypsum supply directions face each other.

1 ... Heat regeneration processing equipment for waste gypsum
2 ... Kiln for regenerating anhydrous gypsum 3 ... Kiln for regenerating semi-water gypsum 4 ... Intermediate hopper 6, 9 ... Drum 7 ... Caster 10 ... Scooping blades 11 ... Hot hopper 12 ... Burner 13 ... Semi-water gypsum charging unit 14 ... Anhydrous gypsum Discharge unit 15 ... Waste gypsum input unit 16 ... Cold hopper 17 ... Semi-water gypsum discharge unit 18 ... Exhaust duct 20 ... Bag filter (dust collector) 24, 25 ... Temperature sensor 26 ... Burner combustion controller 27 ... Static pressure sensor 28 ... Static pressure Pressure / exhaust air volume controller 30, 33, 42 ... Air pressure feeding device 31, 34, 35, 43, 44 ... Air piping 36, 37, 45, 46 ... Damper (discharge destination switching means)

Claims (4)

  A waste gypsum heat regeneration device that regenerates waste gypsum in the form of dihydrate gypsum obtained by crushing and separating waste gypsum board to regenerate it as type II anhydrous gypsum or hemihydrate gypsum. An anhydrous gypsum regeneration kiln that regenerates to type II anhydrous gypsum and a half water gypsum regeneration kiln that regenerates to half water gypsum are arranged in series and connected, and one end of the anhydrous gypsum regeneration kiln Is provided with a burner for supplying hot air and a half-water gypsum charging part for charging hemihydrate gypsum, and at the other end a heat-treated type II anhydrous gypsum discharging part for discharging gypsum, One end of the regeneration kiln is provided with a waste gypsum input portion for inputting waste gypsum, and the other end is provided with a half-water gypsum discharge portion for discharging heat-treated half-water gypsum. In the lower half, the discharge destination of hemihydrate gypsum is the storage bin for storing hemihydrate gypsum. Thermal regeneration treatment apparatus of a waste gypsum, characterized in that a discharge destination switching means capable of switching to either hemihydrate gypsum feeding section of anhydrite reproducing kiln.   A heat-resistant caster is provided around the inner periphery of the anhydrous gypsum regeneration kiln, while a plurality of scraping blades are provided around the inner periphery of the half-water gypsum regeneration kiln. The heat regeneration processing apparatus for waste gypsum according to 1.   The discharge destination of the gypsum fine particles collected by the dust collector provided downstream of the exhaust duct of the hemihydrate gypsum regeneration kiln is a storage bin for storing hemihydrate gypsum, or the half water gypsum input part of the anhydrous gypsum regeneration kiln. 3. The waste gypsum heat regeneration processing apparatus according to claim 1, further comprising a discharge destination switching means that can be switched to either one.   A waste gypsum heat regeneration treatment method in which waste gypsum in the state of dihydrate gypsum obtained by crushing and separating waste gypsum board is heat treated to regenerate as type II anhydrous gypsum or hemihydrate gypsum. An anhydrous gypsum regeneration kiln that regenerates to type II anhydrous gypsum and a half water gypsum regeneration kiln that regenerates to half water gypsum are arranged in series and connected, and one end of the anhydrous gypsum regeneration kiln The unit is equipped with a burner for supplying hot air, and when reclaiming waste gypsum to half-water gypsum, burner combustion is performed so that the temperature in the half-water gypsum regeneration kiln is maintained at the temperature at which waste gypsum is transferred to half-water gypsum. While controlling the amount, throw the waste gypsum into the hemihydrate gypsum kiln and heat it to recover it as hemihydrate gypsum, while reclaiming waste gypsum to type II anhydrous gypsum, the temperature inside the anhydrous gypsum regeneration kiln Waste gypsum translocates to type II anhydrous gypsum While controlling the burner combustion amount so as to maintain the temperature, throw the waste gypsum into the hemihydrate gypsum recycle kiln and preheat it, then put it into the anhydrous gypsum recycle kiln and heat-treat it as type II anhydrous gypsum A method for heating and recycling waste gypsum characterized by being collected.

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