JP2007003024A - Lead bullet recovering system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To recover lead bullets as a contamination source from contaminated earth where lead bullets are scattered, without leading to secondary contamination. <P>SOLUTION: This lead bullet recovering system for recovering the lead bullets scattered in earth and sand, comprises an air supply device, a crushing device 211 having an injection nozzle for injecting the air from the air supply device, a circular pipe conduit 213 forming the air flow circularly flowing along a horizontal face by the air injected from the injection nozzle, an introducing portion 214 for introducing the earth and sand including the scattered lead bullets to the circular pipe conduit 213, and a leading-out portion 216 for leading out the lead bullets circulated in the circular pipe conduit 213 in accompany with the air flow with the earth and sand introduced from the introducing portion 214 and crushed, to an outer peripheral side of a circulating locus, and a classifying device 230 for classifying the earth and sand, and the lead bullets led out from the crushing device 211. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lead bullet collection system that separates and collects lead bullets that are the source of contamination from soil in which lead bullets typified by shooting ranges and the like are scattered.

  Traditionally, lead shots have been used in many shooting ranges in various locations. Lead shots used in shooting contain about 300 to 500 small spherical lead bullets with a diameter of 2 to 4 mm per actual package, and some 20 tons of lead bullets are used every year depending on the shooting range. . In general, the site of the shooting range is vast, and collecting extremely small lead bullets scattered over a wide area may require enormous costs and labor and time. It was left on site.

However, in recent years, soil contamination using abandoned lead bullets as a pollution source has become apparent. As a countermeasure against soil contamination in which lead bullets are scattered, such as shooting ranges where lead bullets are scattered, there is no choice but to remove the lead bullets that are the source of contamination from the soil. Are not necessarily those that remain on the ground surface, but are often hidden by vegetation or accumulated fallen leaves, or buried deep in the ground for many years due to their own weight. .
On the other hand, after excavating contaminated soil and performing wet classification treatment while adding water to the excavated soil, a method of recovering metal pieces by combining specific gravity separation has been proposed (see, for example, Non-patent Document 1). ).

Shigeru Hamada and 4 others, "Metal fragment recovery and purification method from heavy metal-contaminated soil containing metal fragments", 8th meeting on research on groundwater and soil contamination and their prevention measures, 8th groundwater and soil contamination Research Committee Executive Committee on Prevention and its Countermeasures, June 2002, p. 299-300

  However, in the above prior art, wet classification is used in which classification is performed while water is added to the excavated contaminated soil, so that a large amount of treated water is required for classification. When collecting lead bullets scattered in the soil by this method, lead that has eluted in the soil is mixed into the treated water used in large quantities. As a result, the treated water becomes a new source of contamination, and there is a risk of causing secondary contamination due to scattering around the treated water.

  The present invention has been made based on the above-described matters, and its purpose is to recover a lead bullet recovery system that can recover a lead bullet as a pollution source from contaminated soil in which lead bullets are scattered without causing secondary contamination. The purpose is to provide.

  In order to achieve the above object, a first invention provides a lead bullet recovery system for collecting lead bullets scattered in earth and sand, an air supply source, an injection nozzle for injecting air from the air supply source, and the injection nozzle An annular pipe that forms an air flow that flows annularly along a horizontal plane by the air injected from the pipe, an introduction part that introduces earth and sand in which lead bullets are scattered, and an introduction part that is crushed while being introduced from the introduction part A pulverizer having a lead-out portion that leads to the outer circumference side of the circular trajectory along with a certain earth and sand along with an air flow, and classifies the sand and the lead bullet derived from the pulverizer. And a classifying device.

  According to a second invention, in the first invention, the classifier includes a rising pipe connected to a lead-out portion of the pulverizer and a discharge means for discharging lead bullets provided at a lower end of the rising pipe. Then, an upward flow is formed in the rising pipe, the earth and sand are raised using the difference in terminal velocity between the earth and the lead bullet, and the lead bullet contained in the earth and sand is lowered toward the discharge means from the earth and sand. It is characterized by classifying lead bullets.

  According to a third aspect, in the second aspect, the classifier further sends air into the rising pipeline from a lower side than the connecting portion with the lead-out portion to form an upward flow, and from the connecting portion, It further has auxiliary air supply means for raising a part of the rising pipe with accompanying part of earth and sand to be lowered.

  According to the present invention, sand and sand are actively ground while drying the sand and sand by introducing the sand and sand into an air flow that circulates along the horizontal pipe line, thereby improving the efficiency of sand and sand and improving the efficiency of lead bullets. Can be classified from earth and sand. In this way, lead ammunition can be collected efficiently and accurately without adding water in a series of steps, and the lead eluted in the earth and sand will not dissolve into the treated water and become a new source of contamination, and secondary contamination and Accompanying processing can be avoided. At this time, since the annular pipe was installed horizontally so that the air flow circulates along the horizontal plane, the influence of gravity acting on the earth and sand etc. can be made uniform in each place of the orbit, especially when the earth and sand are deposited. It can be avoided that an easy portion is easily formed.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The lead bullet recovery system of the present invention is a system that efficiently collects lead bullets from soil in which lead bullets are scattered, such as an outdoor shooting range. Moreover, since it is assumed that the soil of a vast site is to be treated, it is more effective to investigate the distribution of lead bullets in advance and identify the extent to which the lead bullets are scattered to some extent. However, the lead bullet recovery system according to the following embodiments is not limited to the shooting ground soil in which the lead bullets are scattered, but targets soils of similar environments in which conductors other than the lead bullets are scattered in a solid state. It is also applicable to cases.

FIG. 1 is a schematic diagram of the overall configuration of a lead bullet recovery system according to an embodiment of the present invention.
As shown in FIG. 1, when classified roughly, this system pulverizes contaminated soil contaminated by scattered lead bullets (hereinafter referred to as earth and sand as appropriate) and classifies lead bullets from the earth and sand, and pulverization classification. And a sorting step B for sorting only lead bullets from the earth and sand mixed lead bullets discharged from the step A.

  In the pulverizing and classifying step A, the pre-granulation device 110 that preliminarily granulates the earth and sand supplied by the excavator 100, the air supply device 200 as an air supply source, and the earth and sand refined by the pre-granulation device 110. Is pulverized while being dried by the energy of air from the air supply device 200 to classify lead bullets, and a bag filter 270 to remove dust (residual sediment fine particles etc.) from the exhaust from the pulverization and classification device 210. , And a vacuum pump 295 is used.

  The hydraulic excavator 100 includes a traveling body 101, a revolving body 102 that is turnably provided on the traveling body 101, and an articulated work device 103 that is rotatably connected to the revolving body 102. With such a configuration, the excavator 100 excavates the earth and sand by the working device 103 and inputs it to the pre-fine granulating device 110. Although not particularly illustrated, a belt conveyor or the like may be disposed at the subsequent stage of the hydraulic excavator 100 as needed, and earth and sand may be supplied to the pre-granulating device 110 via the bell and the conveyor.

FIG. 2 is a side view showing the overall configuration of the pre-granulating device 110.
In FIG. 2, reference numeral 1 denotes a frame. The frame 1 forms a gantry with a plurality of support posts and a plurality of support members provided on the plurality of support posts. 2 is a transport conveyor for transporting earth and sand, and the transport conveyor 2 is inclined upward toward the downstream side in the sediment transport direction (right side in FIG. 2) so that the upstream side (left side in FIG. 2) is on the frame 1. The downstream sides are respectively supported by the legs 7. Reference numerals 4 and 5 are driven wheels and drive wheels provided at both ends of the conveyor frame 3 of the conveyor 2, respectively, and are driven between the drive wheels 5 and the driven wheels 4 by rotationally driving the drive wheels 5 with a drive device (not shown). The conveyor belt 6 wound around is circulated.

  Reference numeral 9 denotes a hopper for receiving earth and sand. The hopper 9 is supported by the frame 1 via a support member 10 so as to be positioned on the upstream end of the conveying conveyor 2 in the earth and sand conveying direction. Although not shown in the drawing, a sediment removal outlet (not shown) is provided in the downstream side wall of the hopper 9 so as to face the conveyance belt 6, and the conveyance conveyor 2 is provided via this sediment removal exit. Thus, the earth and sand in the hopper 9 is cut out. The amount of earth and sand conveyed by the conveyor 2 is determined by the opening area of the earth and sand outlet and the conveying speed of the conveying belt 6.

  Reference numeral 11 denotes an additive supply device that supplies additive material to the transport earth and sand on the transport belt 6, and this additive supply device 11 is supported by the frame 1 at a position downstream of the hopper 9 (right side in FIG. 2). Yes. As the additive added to the earth and sand, a material having a property of reducing the plasticity of the earth and sand or a property of enclosing earth and sand particles constituting the earth and sand, such as quick lime and slaked lime, is preferable. The additive supply device 11 stores the additive to be added to the earth and sand, the supply unit 13 for deriving the additive in the storage unit 12 downward, and the additive in the storage unit 12 to the supply unit 13. It is composed of a chute 14 that serves as a funnel for guiding. In the present embodiment, the case where a screw feeder is used for the supply unit 13 has been described as an example, but another feeder such as a rotary feeder may be used.

  Reference numeral 24 denotes a crushing device for mixing the contaminated soil and additive material conveyed on the conveyor 11. Although FIG. 2 illustrates the case where two crushing devices 24 are provided, the number of crushing devices 24 is not limited, and three or more crushing devices 24 may be provided or only one crushing device 24 may be provided. I do not care.

3 is a side view showing the detailed structure of the crushing device 24, FIG. 4 is a cross-sectional view taken along arrows VV in FIG. 3, and FIG. 5 is a cross-sectional view taken along arrows VI-VI in FIG. In these drawings, the same parts as those in the respective drawings are denoted by the same reference numerals, and description thereof is omitted.
3 to 5, reference numeral 151 denotes a support frame. The support frame 151 includes a base frame 151a provided on the conveyor frame 3, a plurality of posts 151b erected on the base frame 151a, and the posts 151b. Bracket 151c. A swing member 152 is swingably supported by the support base 151. The upper end of the swing member 152 is connected to the bracket 151c via a support shaft 153.

  Reference numeral 155 denotes a rotating body for crushing the contaminated soil together with the additive. The rotating body 155 is provided substantially radially with respect to the rotating shaft 156 rotatably held at the tip of the swing member 152 and the rotating shaft 156. And a plurality of blades 157. The rotary shaft 156 includes support portions 156a and 156a at both ends supported by the swing member 152 via bearings 158 and 158, and an intermediate portion 156b interposed between the support portions 156a and 156a.

  The blades 157 are attached to the intermediate portion 156b via the attachment plate 159, and are each curved in the axial direction of the rotation shaft 156. The bending direction is staggered between blades adjacent in the circumferential direction. Further, as shown in FIG. 5, the blades 157 rotate to face the conveying direction of the conveying belt 6, and are curved toward the rear side in the rotational direction toward the radially outer side. The rotation locus of the rotating body 155 is close to the conveyor belt 6.

  Reference numeral 161 denotes a driving device that drives the crushing device 24. The driving device 161 is provided on the bracket 151c on one side (the right side in FIG. 4). 162 is a sprocket provided at the end of the output shaft 161 a of the drive device 161, 163 is a sprocket provided at the end of the support portion 156 a of the rotating shaft 156, and 164 is a chain wound around the sprockets 162 and 163. The driving force of the driving device 161 is transmitted to the rotating body 155 via the chain 164. The rotational speed of the drive device 161 can be adjusted.

  Reference numeral 165 denotes a cover that covers the rotator 155, and this cover 165 prevents scattering of earth and sand and additives that are spun up by the rotator 155. The cover 165 is rotatably supported by a rotation shaft 156 (support portion 156a) and can swing relative to the swing member 152. On the side surface of the cover 165, as shown in FIG. 4, a plurality of plates 166 having grooves 166a formed in an arc shape concentric with the rotating shaft 156 (support portion 156a) (in this example, two on each side, a total of four plates 166). ) Installed. Reference numeral 167 denotes a pin provided inside the swinging member 152, and the pin 167 is loosely fitted in the groove 166 a of the plate 166. As a result, when a large foreign matter is mixed in the transport earth and sand on the transport belt 6, the swinging member 152 is prevented from swinging and the foreign matter is caught between the rotating body 155 and the transport belt 6. At the same time, the gap between the cover 165 and the conveyor belt 6 is made as small as possible even when swinging to prevent scattering of earth and sand.

  Returning to FIG. 1, the air supply device 200 includes a so-called roots type positive displacement blower 201. The blower 201 is driven by a driving force transmitted from the driving device 202 via the transmission belt 203. Reference numeral 206 denotes a drive rotor that is rotationally driven by the drive device 202. Although not shown, the driven rotor meshes with the driven rotor via a transmission gear, and the driven rotor and the driven rotor are oppositely synchronized. Rotate in the direction to compress and discharge the intake air.

  The casing of the blower 201 is provided with a suction port 204 and a discharge port 205, and a silencer 207 is attached to the upper end of the suction port 204. On the other hand, the discharge port 205 protrudes from a lower position of the casing 206 and is connected to the pulverizing and classifying device 210 via the connection pipe 208.

6 is a plan view of the pulverizing and classifying apparatus 210, FIG. 7 is a horizontal sectional view thereof, and FIG. 8 is a partially broken side view thereof.
6 to 8, the pulverizing / classifying device 210 includes a pulverizing device 211 in the former stage for dry pulverization of the input earth and sand, and a classification device 230 (described later) for classifying the earth and sand crushed by the pulverizing device 211. I have.

  The pulverizer 211 includes an injection nozzle 212 that injects air from the air supply device 200, an annular pipe 213 that forms an annular air flow using the air injected from the injection nozzle 212, and earth and sand that are supplied to the annular pipe 213. And a lead-out portion 216 connected to the outer peripheral side of the annular flow path formed by the annular conduit 213.

  The annular pipe line 213 is formed in a ring shape by a plurality of pipes 217 to 219, is supported by a support member (not shown) in a horizontal state, and forms an air flow that flows in a ring shape along a horizontal plane. The pipes 217 to 219 are connected by bolting flanges 223 between adjacent ones. Since the annular pipe 213 can be divided by the flange structure, maintenance, inspection, repair and the like are easy. There is no limitation on the number of divisions of the annular conduit 213. In addition, a sealing material (not shown) is interposed between the opposing flanges 223 and 223 to maintain airtightness.

  The injection nozzle 212 is provided on the outer peripheral side of the pipe 217 constituting the annular conduit 213. In this embodiment, the injection nozzle 212 is provided only in the pipe 217, but the injection nozzle 212 may be provided in any pipe including the other pipes 218 and 219, or may be provided in a plurality of pipes. Further, the air injection direction of the injection nozzle 212 is directed in the inward direction with respect to a line perpendicular to the outer wall surface of the annular conduit 213 so that an annular air flow flowing in one direction is formed in the annular conduit 213. The airflow a is inclined in the circumferential direction (see FIG. 7).

  The above injection nozzle 212 is covered with an air tank 225 connected to the air supply device 200 through a connection pipe 208. The air tank 225 is appropriately composed of a steel plate or the like, and airtightness is ensured by a sealing material (not shown) or the like. When air b (see FIG. 7) from the air supply device 200 is introduced into the air tank 225, the internal pressure of the air tank 225 rises, and high-speed air is ejected from the small-diameter injection nozzle 212 into the annular conduit 213. An annular air flow a is formed.

  The introduction part 214 is provided in any one of the pipes constituting the annular pipe line 213. In the present embodiment, the introduction unit 214 is provided in the pipe 219, and earth and sand are introduced vertically downward through the introduction unit 214 into the air flow a that circulates along the horizontal plane. In addition, the introduction unit 214 is provided with a hopper 220 for receiving the introduced earth and sand and a quantitative supply part 221 for supplying the earth and sand in a fixed amount. Although FIG. 8 illustrates a case where a rotary feeder is used as the fixed amount supply unit 221, it may be replaced with a screw feeder or the like. In FIG. 6, the quantitative supply unit 221 and the hopper 220 are not shown.

  On the other hand, the lead-out part 216 is also provided in any of the pipes that constitute the annular pipe line 213. In the present embodiment, the derivation unit 216 is provided on the outer peripheral side of the air flow circulation locus in the pipe 218, and the sediment discharge direction of the derivation unit 216 is also along the horizontal plane. A suction force by the vacuum pump 295 also acts on the lead-out portion 216, and lead bullets that circulate in the annular conduit 213 along with the air flow together with the earth and sand introduced from the introduction portion 214 are circulated around the circumference of the orbit. Is sucked to the side and led out of the annular conduit 213 through the lead-out portion 216.

  As shown in FIG. 8, the classification device 230 includes a rising pipe 231 configured by vertically setting a cylindrical pipe, a discharge portion 232 provided below the rising pipe 231, and a lower portion than the connection portion 216. An auxiliary air supply device 222 that feeds air into the rising pipe 231 from the side to form an upward flow is provided. A connecting portion 233 connected to the lead-out portion 216 of the crushing device 211 is connected to the startup pipe 231 in a “T” shape.

  The discharge unit 232 is configured by a so-called rotary feeder, and is bolted to the start-up pipe 231 with a seal material (not shown) interposed therebetween. The schematic configuration is such that a rotor 241 having a plurality of partition walls 240 radially provided on a rotating shaft 239 is provided in a casing 238, and a mixture of lead bullets and the like that have fallen after being classified as earth and sand by a rising pipe 231 is provided for each partition wall. When the rotor 241 is rotated by being introduced into the space between 240, it is sequentially discharged downward.

  The auxiliary air supply device 222 includes an air tank 234 interposed between the startup pipe 231 and the discharge unit 232, and a blower 235 that supplies air to the air tank 234. The air tank 234 includes a connection pipe 236 that connects the start-up pipe 231 and the discharge portion casing 238. The connecting pipe 236 is provided with a plurality of slits 237 on the outer periphery thereof, and the air sent from the blower 235 to the air tank 234 flows from the slit 237 of the connecting pipe 236 to form an upward flow in the rising pipe 231. To do. As a result, a part of the earth and sand that is mixed with the lead bullet and is going to descend from the connection portion 216 is caused to accompany the upward flow formed by the auxiliary air supply device 222 and the startup pipe 231 is raised.

  Here, in the case where a substance is caused to ascend with an ascending air current, the difference between the ascending air current velocity and the mass transfer speed when the buoyancy acting on the material and gravity are balanced is called the terminal velocity. The classification device 230 in the present embodiment classifies the earth and sand and the lead ammunition using the difference in terminal velocity between the earth and sand and the lead ammunition. Therefore, the suction force by the vacuum pump 295, the diameter of the pipe 231 of the classifier 230, the driving speed of the air supply device 200 or the blower 235, the number of the injection nozzles 212, the diameter of the injection holes, and the like also take into account the properties of the earth and sand. And the flow velocity of the air flow that has reached the start-up pipe 231 is set to a value between the terminal velocity of earth and sand and the terminal velocity of lead bullets. That is, when the earth and sand from the pulverizer 211 reaches the rising pipe 231, only the earth and sand are raised along with the air flow, and lead bullets contained in the earth and sand are lowered and guided to the discharge unit 232.

FIG. 9 is a cross-sectional view showing the overall configuration of the bag filter 270 constituting the lead bullet recovery system according to the embodiment of the present invention. In this figure, the same parts as those in the previous drawings are given the same reference numerals. Description is omitted.
The bag filter 270 shown in FIG. 9 is a filtration type dust collector having a known configuration, and includes a dust collection chamber 271 that forms a main body, a chute 272 that is connected to the lower portion of the dust collection chamber 271, and a discharge portion 273 that is connected to the lower portion of the chute 272. It is roughly composed.

  The dust collection chamber 271 is formed of a cylindrical body having an open top and bottom section, and flanges 274 and 275 are provided at upper and lower end portions thereof, and the top plate 276 and the chute 272 are interposed via the flanges 274 and 275. And are respectively bolted. The chute 272 is provided with an introduction port 277. A connecting pipe 263 connected to the start-up pipe 231 of the pulverizing / classifying device 210 is connected to the introduction pipe 277 via a flange 279 provided at the end. The top plate 276 is provided with a discharge port 280 connected to a discharge pipe 281. A connection pipe 283 connected to the vacuum pump 295 is connected to the discharge pipe 281 through a flange 282. A plurality of filters 284 are disposed inside the dust collection chamber 271 so as to overlap each other. The filter 284 is formed of a fine filter cloth that collects fine dust (such as fine sediment particles).

  The chute 272 has a substantially quadrangular pyramid shape whose diameter is reduced downward so as to serve as a funnel for guiding the dust separated in the dust collecting chamber 271 to the discharge part 273, and a sealing material ( It is bolted to the dust collection chamber 271 with a not-shown) interposed therebetween.

  The discharge part 273 is constituted by a so-called rotary feeder, similar to the discharge part 232 of the pulverizing and classifying device 210, and is attached to the lower end of the chute 272 by bolting each other's flanges with a seal material (not shown) interposed therebetween. ing. Specifically, a rotor 288 in which a plurality of partition walls 287 are provided radially on a rotating shaft 286 is provided in a casing 285, and the collected dust (sediment fine particles) is a space between the partition walls 287. Then, the rotor 288 is rotated to sequentially discharge downward. The discharge unit 273 is not limited to a rotary feeder, and a so-called screw feeder or the like may be used.

  Returning to FIG. 1, in the sorting step B, a lead bullet collecting device 500 that collects lead bullets from the earth and sand that has been refined through the pulverization and classification step A by using magnetic force is used.

FIG. 10 is a side sectional view showing a schematic configuration of a lead bullet recovery apparatus 500 constituting the lead bullet recovery system according to the embodiment of the present invention. In this figure, the same reference numerals are given to the same parts as in the previous drawings. The description is omitted.
As shown in FIG. 10, the lead bullet recovery device 500 includes a hopper 501 that receives lead bullets (sorted matter) mixed with earth and sand classified by the classification device 230, a conveyor 502 that conveys the sorted matter received by the hopper 501, and a conveyor A sorter 503 provided in the vicinity of the discharge end of 502 is provided, and lead bullets are sorted and collected by the action of an alternating magnetic field generated from the sorter 503 from the sorts conveyed on the conveyor 502. It has become.

  The hopper 501 is a frame-shaped member that expands upward, and is provided on the upstream end (the left side in FIG. 10) of the conveyor 502, and is discharged from the discharge unit 232 of the pulverizing and classifying device 210. It plays a role in accepting selected items such as lead bullets and relatively large earth and sand. Therefore, the lead bullet recovery device 500 is arranged such that the hopper 501 is positioned below the discharge part 232 of the pulverization / classification device 210.

  The conveyor 502 includes a conveyor frame 504, drive wheels 505 and driven wheels 506 that are rotatably provided at both ends of the conveyor frame 504, and a conveyor belt 507 that is wound between the drive wheels 505 and the driven wheels 506. Not supported by a pedestal. As a result, the driving wheel 505 is driven to rotate by a driving device (not shown), and the conveyor belt 507 is driven to circulate between the driven wheel 506 and the driven wheel 506.

  The sorter 503 includes a drum 508 that is slidably brought into contact with the driven wheel 506 in the inner peripheral portion of the driven wheel 506, and a plurality of magnets that are fixedly disposed on the inner peripheral portion of the drum 508 so that the polarity changes alternately. 509, 510. The drum 508 is configured to be rotatable in a direction opposite to the rotation direction of the driven wheel 506 by a driving device (not shown) different from the driving device that rotationally drives the driving wheel 505, and the drum 508 is configured to rotate the conveyor belt 507. By rotating in the opposite direction, an alternating magnetic field is formed on the conveyor belt 507.

  As a result, when the crossing of the alternating magnetic field formed by the sorter 503 is transported by the conveyor belt 507 to the surface of the lead bullet, which is a conductor contained in the sorted matter received by the hopper 501, near its discharge end. An eddy current will be generated. Since the magnetic field generated by this eddy current is always the same polarity as the alternating magnetic field of the sorter 503, the lead bullets are instantaneously blown off from the conveyor belt 507, and the bottomed frame is arranged slightly apart from the discharge end of the conveyor 507. It is recovered in a recovery box 511 in the form of a tube. Since stones, earth and sand, etc. that do not generate eddy currents are dropped from the discharge end of the conveyor 507 without being blown off, the lead bullets are thereby separated from other selected items.

Next, the operation and action of the lead bullet recovery system of the present embodiment having the above configuration will be described.
In the system shown in FIG. 1, first, when excavating the target soil with the hydraulic excavator 100 and putting it into the hopper 9 of the pre-granulating device 110, the soil put into the hopper 9 is sequentially transferred by the conveyor 2 to the hopper 9. It is conveyed outside, and during the conveyance, it is pre-ground (pre-fine-grained) by the crushing device 24 together with the additive such as lime supplied from the additive supply device 11. Thus, when the additive is added and crushed and mixed with the additive, the earth and sand is reduced in plasticity. As a result, the earth and sand are crushed to a particle size of, for example, about 10 mm, and the additive is added to the surface. It is discharged in the attached state.

  However, in the present embodiment, when the earth and sand excavated by the hydraulic excavator 100 forms a large earth lump, or when the earth is highly viscous earth and sand that is difficult to handle, it is supplied directly to the pulverizing and classifying device 210. In this way, pretreatment is performed by using the pre-granulating device 110. For example, when the earth and sand do not form a large earth lump, specifically, the particle diameter of the earth lump is already about 10 mm or In the case of less than that, it is not always necessary to use the pre-granulating device 110, and the earth and sand may be directly supplied to the pulverizing and classifying device 210. It is also conceivable that earth and sand having a size of about 10 mm or less are preliminarily sorted using a sieve in front of the pulverizing and classifying device 210 and put into the pulverizing and classifying device 210. When a sieve is used, foreign matters such as large stones are removed in advance, so that biting into the pulverizing and classifying device 210 is prevented in advance.

  The earth and sand which has been crushed in advance by the pre-fine graining device 110 and whose particle size has become relatively small is put into the pulverization and classification device 210. At this time, a conveyor or the like may be disposed after the pre-granulating device 110, and earth and sand may be supplied to the pulverizing and classifying device 210 by this conveyor. Further, even if the earth and sand are not continuously supplied from the pre-granulating device 110 to the pulverizing and classifying device 210, for example, the earth and sand discharged from the pre-granulating device 110 is temporarily used for curing and drying. It may be stocked elsewhere.

  In the pulverizer 211, the supply air from the blower 201 is pressurized in the air tank 225 and discharged from the injection nozzle 212 into the annular pipe 213 at a high speed. When earth and sand are supplied into the annular pipe 213, the earth and sand circulates along with the air flow in the annular pipe 213 and is dried by being exposed to the air flow to reduce its plasticity (brittle state) In addition, it is pulverized and further refined by colliding with the inner wall of the pipeline, the injection air from the injection nozzle 213, or other earth and sand particles in the middle of the process. The pulverized earth and sand are sucked by the vacuum pump 295 and discharged from the pulverizer 211 via the outlet unit 216. The earth and sand that are not discharged from the lead-out part 216 continuously circulates in the annular pipe 213, and is then crushed and discharged.

  When the earth and sand discharged from the pulverizer 211 are introduced into the classifier 230, components having large specific gravity including lead bullets are separated from the earth and sand fine particles from the difference in the terminal velocity in the start-up pipe 231 and located at the most downstream side. It is discharged from the discharge unit 232 and guided to the lead bullet recovery device 500. On the other hand, fine sediment particles discharged from the classifier 230 are introduced into the bag filter 270 through the connecting pipe 263 along with the air flow, collected by the filter 284, and released to the atmosphere as clean air. The collected earth and sand are discharged from the discharge unit 272, and are separately transferred to a step of performing a countermeasure against contamination such as insolubilization using a conveyor or the like (not shown).

  Lead bullets and the like introduced into the lead bullet collecting device 500 are received by the hopper 501 and conveyed by the conveyor belt 507. Then, when crossing the alternating magnetic field generated from the sorter 503, only lead bullets are blown off from the conveyor belt 507, separated from other foreign matters such as stones, and collected in the collection box 511.

  In the present embodiment, the sand and sand is actively pulverized while being dried by introducing the earth and sand into an air flow that circulates around the annular pipe line 213 along the horizontal plane. Can be efficiently classified from earth and sand. In this way, lead ammunition can be recovered efficiently and with high accuracy without adding water in a series of steps. Therefore, the lead eluted in the earth and sand does not dissolve in the treated water and become a new source of contamination. Can be avoided. At this time, in the present embodiment, since the annular conduit 213 is horizontally installed so that the air flow circulates along the horizontal plane, the influence of gravity is applied to various places of the circulatory trajectory as compared with the case where it is placed vertically. It can be made uniform, and in particular, it is difficult to make a place where earth and sand are easily deposited.

  Further, the lead-out portion 216 of the crushing device 211 is provided on the outer peripheral side of the annular conduit 213, and the classification efficiency is better than sucking lead bullets from the inner peripheral side of the annular conduit 213. Since lead bullets or the like circulate, they are subjected to the action of centrifugal force and pass through the outer peripheral side of the annular conduit 213. Therefore, as shown in this example, the lead 216 is provided on the outer peripheral side to pass through the vicinity. By sucking bullets, the lead bullet discharge rate is increased and classification accuracy is improved. In addition, since a large unground soil mass is heavy and has a large inertia to circulate, it is not sucked out from the outlet 216 during unground.

  Further, in the present embodiment, since the annular pipe 213 is installed horizontally, the suction air speed at the outlet 216 of the annular pipe 213 is set to be equal to or less than the terminal velocity of the lead bullet from the viewpoint of ensuring the crushing accuracy suitable for classification. It is preferable to set so that In the horizontal plane, it is only necessary to ensure the wind speed at which the object flows in the pipe, so even if the suction wind speed is less than the terminal velocity of the lead bullet, the lead bullet is discharged from the discharge port without staying in the crusher. . The fact that the output of the vacuum pump 295 and the like can be kept low in this way is also an advantage of the annular pipe line 213 being installed horizontally.

  Further, on-site processing becomes possible due to the fact that no new object to be processed due to secondary contamination is generated, and that each device is composed of compact equipment that can be transported by trailer. In addition, this eliminates the need to take the soil to be treated to a plant or the like outside the venue, and can suppress the generation of sediment transport costs. Furthermore, the entire processing cost can be reduced and effective purification can be realized by giving priority to pollution prevention measures such as insolubilization treatment and washing treatment on the earth and sand from which lead bullets have been removed. Further, since the pulverization is accompanied by drying, it is difficult for the crushed earth and sand to adhere to and grow on the tube wall, for example. Furthermore, since the classification device 230 classifies lead bullets and earth and sand using the difference in terminal velocity between earth and sand and lead bullets, the use of the classification device 230 causes problems such as clogging that occurs when a screen is used. Can be avoided. This can also improve the lead bullet recovery efficiency.

  Further, since the earth and sand can be dried and pulverized without using a heat source such as a heater, the input energy can be suppressed. As a result, operation costs can be reduced, and processing costs can be reduced. Moreover, since the portability as a system is high as mentioned above, the system can be operated in general according to the processing site, and the construction period can be shortened. This also makes it possible to keep processing costs low.

  In the above, for the purpose of lowering the plasticity of the earth and sand, the earth and sand were crushed and mixed together with the additive using the pre-fine graining device 110, for example, A so-called soil improvement machine can be used in place of the pre-granulating device 110. Generally, a soil improvement machine is agitated and mixed with a hopper that receives earth and sand, a conveyor that conveys earth and sand outside the hopper, an additive supply device that supplies additive, and an additive that has been added with earth and sand from a conveyor. And a discharge conveyor that discharges the mixture of earth and sand discharged from the mixing device and the additive to the outside of the machine. Further, usually, the soil conditioner is often provided with a sieve above the hopper, which is also suitable when it is necessary to remove large foreign matters in advance. In addition, the soil improvement machines include a stationary type and a self-propelled type, but any of them can be applied. However, even in the pre-granulating device 110 described above, a traveling body can be provided at the lower part of the frame 1 so as to be capable of self-running, and a fixed or vibrating sieve is provided above the hopper 9. It can also be set as the structure provided.

  Further, as shown in FIG. 11, by adding a heating means 600 such as a heater to a connecting pipe 208 connecting the air supply device 200 and the pulverizing / classifying device 210, the air supplied to the pulverizing / classifying device 210 is supplied. If the temperature can be adjusted, the air that has been heated by the heating means 600 is supplied to the pulverizing and classifying device 210, whereby the earth and sand can be dried more efficiently. Thereby, even if earth and sand having a relatively high water content ratio are supplied to the pulverizing and classifying apparatus 210, the pulverizing and classifying lead can be efficiently crushed.

  Further, although the rotary feeder is used in various places such as the pulverizing and classifying device 210, a discharge device other than the rotary feeder may be used as long as the airtightness in the air pipe can be maintained. For example, a screw feeder or a double damper can be applied. The double damper is intermittently discharged due to its structure, but can be applied by setting the opening and closing speed within a range that does not hinder the discharge.

It is the schematic of the whole structure of the lead bullet recovery system which concerns on one embodiment of this invention. It is a side view which shows the whole structure of the pre-granulation apparatus which comprises the lead bullet recovery system which concerns on one embodiment of this invention. It is a side view showing the detailed structure of the crushing apparatus with which the pre-granulation apparatus which comprises the lead bullet recovery system which concerns on one embodiment of this invention was equipped. It is a VV arrow sectional view in Drawing 3 showing the detailed structure of the crushing device with which the pre-granulation device which constitutes the lead bullet recovery system concerning one embodiment of the present invention was equipped. It is VI-VI arrow sectional drawing in FIG. 4 showing the detailed structure of the crushing apparatus with which the pre-granulation apparatus which comprises the lead bullet recovery system which concerns on one embodiment of this invention was equipped. It is a top view of the crushing and classifying device constituting the lead bullet recovery system according to the embodiment of the present invention. It is a horizontal sectional view of the crushing and classifying device constituting the lead bullet recovery system according to one embodiment of the present invention. It is a partially broken side view of the crushing and classifying device constituting the lead bullet recovery system according to the embodiment of the present invention. It is sectional drawing showing the whole bag filter structure which comprises the lead bullet recovery system which concerns on one embodiment of this invention. It is a sectional side view showing a schematic structure of a lead bullet recovery device which constitutes a lead bullet recovery system concerning one embodiment of the present invention. It is the schematic of the whole structure of the lead bullet recovery system of this invention which added the heating means.

Explanation of symbols

200 Air supply device 211 Crushing device 212 Injection nozzle 213 Annular pipe 214 Introducing section 216 Deriving section 222 Auxiliary air supply apparatus 230 Classifying apparatus 231 Rising pipe 232 Discharging section

Claims (3)

In the lead bullet recovery system that collects lead bullets scattered in the earth and sand,
An air supply,
An injection nozzle that injects air from the air supply source, an annular pipe that forms an air flow that flows annularly along a horizontal plane by the air that is jetted from the injection nozzle, and earth and sand in which lead bullets are scattered in the annular pipe A pulverization apparatus having an introduction part to be introduced, and a lead-out part for deriving lead bullets circulating around the annular pipe along with the air flow along with the earth and sand introduced and crushed from the introduction part, to the outer peripheral side of the circular trajectory When,
A lead bullet recovery system comprising a classification device for classifying earth and sand derived from the pulverizer and lead bullets.   The classifier includes a rising pipe connected to the pulverizer outlet and a discharge means for discharging lead bullets provided at the lower end of the rising pipe, and forms an upward flow in the rising pipe. The lead ammunition is classified from the earth and sand by raising the earth and sand using the difference in terminal velocity between the earth and sand and lowering the lead bullet contained in the earth and sand toward the discharge means. The lead bullet recovery system according to 1.   The classifier forms an upward flow by sending air into the rising pipeline further from the lower side than the connection part with the outlet part, and entrains some earth and sand to be lowered from the connection part. The lead bullet recovery system according to claim 2, further comprising auxiliary air supply means for raising the rising pipeline.

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