JP2008307449A - Plant for upgrading excavated soil comprising low-quality surplus soil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the shortage of dumping site for waste soil and environmental problems associated with a prior art method of disposing of soil excavated in a road construction site whereby the excavated soil is dumped into a site designated for waste soil disposal, and to alleviate the seriously worsening problems of destroying the natural environment and of diminishing natural resources necessary for road construction caused by mining road-construction materials, by converting and recycling excavated soil (surplus soil of construction works) and construction waste such as concrete lumps and asphalt lumps into a material useful for roadbed construction or pipe protection. <P>SOLUTION: Disclosed is a method of preparing a material useful for roadbed construction or pipe protection comprising the process of admixing excavated soil with construction waste such as concrete lumps, asphalt lumps, or a mixture thereof, the process of crushing the resulting mixture, the process of adding lime into the crushed mixture, classifying the above mixture using a sifter into groups of crushed particles namely a group of particles having a particle size of 40 to 30 mm, a group of particles having a particle size of 30 to 20 mm, a group of particles having a particle size of 20 to 7 mm, and a group of particles having a particle size of not greater than 7 mm, and the process of mixing the four groups of the crushed particles with each other at a prescribed ratio. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to an excavation residual soil reforming plant for producing materials such as roadbed materials and pipe winding materials by modifying excavation soil containing defective residual soil.
According to the present invention, clay excavated soil or the like containing a large amount of water that has been discarded as defective residual soil can be reclaimed as a material for a roadbed material or a pipe protection material.

Conventional paved roads are constructed in the order of the roadbed and surface layer on the roadbed built by ordinary road earthwork, and the roadbed is the soil part 1m below the roadbed, and the thickness of the pavement. It is the basis to decide. The roadbed is an important part that disperses traffic load and conveys it to the roadbed, and is usually divided into upper and lower roadbeds in order to achieve a mechanically balanced structure according to the weighted load. ing. In addition, as the surface layer resists friction and shear due to traffic load at the top of the pavement, a highly durable asphalt of a heated mixture is often used.
When excavating a paved road by construction work such as gas, water, sewerage, etc., it is excavated from the surface layer to the roadbed.
The remaining soil excavated on the paved road contains sand, clay, gravel, concrete waste, asphalt waste, etc., and even if it is backfilled as it is, it cannot be fully compacted and may cause ground subsidence. However, it could not be used as backfill material for roadbeds.

Construction work such as gas, water and sewerage needs to be promptly and reliably restored in order to minimize traffic problems. For this reason, virgin crushed stone is used as the main material for roads for conventional restoration work, and some of the surface concrete lumps and asphalt lumps are crushed and processed to the specified granularity, respectively. However, pipe materials that protect upper and lower roadbed materials, gas, water, and sewerage were not able to be reused because of their strict quality requirements for compressive strength and granularity. . For this reason, the roadbed and roadbed soil excavated by a series of works is discarded except for good quality, and the roadbed material and pipe protection material is backfilled with virgin crushed stone and sand. It has been performed conventionally.
Recently, various attempts have been made to process these residual soils and use them again as roadbed backfill materials, and high-quality residual soils have been recycled and used as roadbed backfill materials. .
However, some clay soils that contain a lot of water (4 types of soil classification standards and mud soil according to the Ordinance of the Ministry of Land, Infrastructure, Transport and Tourism) are generated in the excavation site. Because it has been destroyed. The rate of occurrence of this poor-quality residual soil varies depending on the construction site, but is a large amount that accounts for 40 to 60% of the entire excavated soil.

Japanese Patent Laid-Open No. 10-224853, JP 2000-50474, JP 2000-358101 A, JP 2001-251440 A

In the case of the conventional construction method for paved road restoration, there are various problems such as the collection of earth and sand for backfilling, mainly the roadbed material, the disposal and disposal of excavated earth and sand, and the transportation cost of excavated earth and sand.
That is, the collection of earth and sand for roadbed materials destroys the natural environment and depletes valuable natural resources, so natural destruction and resource depletion are in a serious state. In addition, the distance to the collection site is long, and the dump outbound route becomes empty, which is not only inefficient, but also increases the carbon dioxide emitted by the transport vehicle, causing environmental damage.
Furthermore, conventional reuse of construction waste alone is not used as a roadbed material, and the waste of clay and poor residual soil containing a large amount of water from excavated soil (construction surplus soil) are industrially discarded. Since the waste is disposed of as a waste at the designated waste disposal site, the number of waste disposal sites has been decreasing year by year, and since it is far away and the return path of the dump is empty, Not only is it inefficient and uneconomical, it also causes environmental destruction.
The object of the present invention is to recycle the excavated soil and concrete lump of construction waste, asphalt lump, etc. as roadbed material, etc., thereby dramatically increasing the reuse rate as a secondary effect as a designated waste disposal site. It is to solve the shortage problem and reduce the cause of environmental destruction.

According to the present invention, an oval disc screen that screens defective soil that needs to be pre-processed into an object of size 70 mm or larger and the following is stored. The first curing stock to be retained for mixing with raw materials such as ascongala hoppers in the excavated soil treatment plant described later, and the improved material to be added as a stable treatment material to defective residual soil of 70 mm or less screened by an elliptical disk screen The improved material silo, the rotary quantitative feeder that adjusts the amount of the improved material sent out from the improved material silo,
A mixer that mixes 70mm or less defective soil that has been screened by an elliptical disc screen with the improved material sent out from the silo, and stores the 70mm or less defective soil that has been improved by mixing the improved material with the mixer. The second curing stock to be stored as excavated soil in the excavated soil treatment plant, concrete lump of construction waste, asphalt lump, and poor residual soil of 70 mm or more stored in the first cured stock Ascongala hoppers, grizzly sieving metering feeders that feed raw materials stored in ascongala hoppers, and sort them into items larger than a certain size and the following: Compression primary crusher that crushes raw materials over a certain size sent out from the machine, high quality excavation residue and the second High quality excavation surplus hopper to which defective surplus soil of 70mm or less stored in raw stock is thrown in, pan conveyor type quantitative supply machine that sends out excavation residual soil of excavation residual soil hopper, excavation soil sent out from bread conveyor type quantitative supply machine Grizzly vibratory sieve that sifts into particles with a particle size of 80 mm or less, lime silo for storing lime, rotary quantitative feeder for feeding lime from lime silo, particle size of 80 mm or less screened by grizzly vibratory sieve Good quality excavated residual soil, raw material of a certain size or less, screened by a grizzly sieving metering feeder, and iron pieces in a crushed material of a primary crusher plus lime silo lime Magnetic separator that removes magnetic metals, and excavated soil, raw materials, and broken raw materials from which metal pieces such as iron pieces sent from the magnetic separator are removed The sieve and the mixture of the lime and the crushed material of the raw material, the raw material, and the lime which is sieved by the vibration sieve An intermediate raw material that holds as a raw material a mixture of excavated soil, raw material, raw material crushed material and lime that is crushed and made into a particle size of 40 mm or less. A hopper, a belt-type quantitative feeder that feeds the intermediate raw material held by the intermediate raw material hopper, has a 30 mm mesh sieve on the top, a 20 mm mesh sieve on the middle, and a 7 mm mesh sieve on the bottom. Multistage vibratory sieve, stockyard for holding intermediate material remaining on 30mm mesh sieve of multistage vibratory sieve, remaining on 20mm mesh sieve of multistage vibratory sieve The first intermediate hopper that holds the intermediate raw material passes through the 7 mm mesh sieve of the second intermediate hopper that holds the intermediate material remaining in the 7 mm mesh sieve of the multistage vibratory sieve. Belt type fixed quantity feeder, multistage vibratory sieving machine, which distributes the intermediate raw material that has passed the 20mm mesh of the multistage vibratory sieving machine to the second intermediate hopper and stockyard The belt-type metering feeder that distributes the intermediate material that has passed through the 7 mm mesh to the third intermediate hopper and the stockyard, the lime silo that stores lime, the rotary metering feeder that sends lime from the lime silo, the first The first belt type fixed-quantity feeder that feeds the intermediate raw material held in the intermediate hopper, the second belt type that sends out the intermediate raw material held in the second intermediate hopper A fixed amount feeder, a third belt type fixed amount feeder that sends out the intermediate material held in the third intermediate hopper, a first belt type fixed amount feeder, a second belt type fixed amount feeder, and a third belt type fixed amount Excavation including poor residual soil that is obtained by recycling excavated soil with intermediate raw material sent from a feeder and a mixer that mixes lime delivered from a rotary metering feeder to obtain roadbed material A soil reforming plant has been realized.
According to the present invention, the excavated soil containing defective residual soil can be improved and reused as a roadbed material or a pipe protection material, so that resources can be effectively used and environmental destruction can be prevented.

According to the present invention, the excavated soil containing defective residual soil that causes environmental destruction has been improved to be a conventional backfill material for roadbed materials such as crushed stones and pipe protective materials, so that the waste can be recycled. Effectively used as a resource, it contributes to natural destruction by collecting aggregates, prevention of resource depletion, and supplements the serious shortage of waste disposal sites. In addition, since the cost of transporting excavated earth and sand is saved, various problems occurring with the current road repair can be solved simultaneously.

FIG. 1 is a diagram showing a configuration of a part of a pretreatment step for defective residual soil in a drilling soil reforming plant including defective residual soil according to the present invention.
In FIG. 1, 2 is a poor-quality residual soil hopper. The defective residual soil hopper 2 is charged with clay-based defective residual soil containing a large amount of water (the fourth type of soil classification criteria and mud soil of the Ordinance of the Ministry of Land, Infrastructure, Transport and Tourism).
Reference numeral 1 denotes an elliptical disk screen. The elliptical disc screen 1 is screened to a size of 70 mm or more and the following, while transporting clay-like defective soil containing a large amount of water mixed with stone.
Reference numeral 2 denotes a hopper into which defective residual soil of 70 mm or less that has been screened by the elliptical disc screen 1 is put.
S1 is a stock yard for temporarily stocking defective soil of 70 mm or more screened by the elliptical disc screen 1.

6 is an agitation tank in which 1 to 15% of the improving material is added to the poor residual soil of 70 mm or more screened by the elliptical disk screen 1 and stirred.
S2 is a stock yard for stocking 70 mm or more of defective soil with an improved material added in the stirring tank 6.
Reference numeral 3 denotes a belt-type quantitative feeder for transporting the poor residual soil of the hopper 2.
4 is an improvement material silo for storing the improvement material.
Reference numeral 41 denotes a rotary quantitative feeder that feeds the improved material from the improved material silo 4. The rotary type quantitative feeder 41 can adjust the amount of the improved material sent out from the improved material silo 4 by changing the rotational speed.
5 is a mixer that mixes the improved material fed from the rotary type quantitative feeder 41 with the defective residual soil of the defective residual hopper 2 delivered from the belt type quantitative feeder 3.
S3 is a stock yard that stocks the defective residual soil of 70 mm or less mixed with the improved material in the mixer 5.

The operation of the pre-processing portion of the defective residual soil having such a configuration will be described as follows.
The clay-like unsatisfactory soil containing a large amount of water mixed with stones is screened by the elliptical disk screen 1 into those having a size of 70 mm or more and the following. The poor residual soil of 70 mm or more screened by the elliptical disk screen 1 is excavated soil mainly composed of stones from which moisture has been removed. Therefore, after the primary storage in the stockyard S1, it is put into the stirring tank 6 and improved. Is stored in the stock yard S2 which stocks defective soil of 70 mm or more, and is processed in addition to raw materials such as concrete lumps and asphalt lumps of the excavated soil treatment plant described later.
The poor residual soil of 70 mm or less sent out from the belt-type quantitative feeder 3 is mainly made of clay soil containing a lot of moisture. Therefore, the improvement material of the silo 4 is added as a stabilizing treatment material and mixed by the mixer 5. The soil quality is improved. The amount of the improved material to be added is adjusted depending on the characteristics of the defective residual soil, but the mixing ratio of the improved material is adjusted by changing the number of rotations of the rotary quantitative feeder 41 from the silo 4. .
Defective soil of 70 mm or less whose quality has been improved by mixing the improved material by the mixer 5 is stored in the curing stock S3 and processed in addition to the raw material of the excavated soil treatment plant described later.

FIG. 2 is a diagram showing a configuration of a processing plant portion that regenerates excavation surplus soil of the excavation surplus soil reforming plant including defective surplus soil according to the present invention into upper-layer roadbed material, lower-layer roadbed material, roadbed material and the like.
In FIG. 2, 7 is an ascongala hopper. Ascongala hopper 7 is filled with concrete lump of construction waste, asphalt lump, and defective soil of 70 mm or more stored in curing stock S2 of FIG.
Reference numeral 8 denotes a grizzly sieving quantitative feeder. Grizzly type sieving and metering feeder 8 transports concrete lump of construction waste, asphalt lump, and waste soil of 70mm or more which is stored in ascongala hopper 7 Sift out.
9 is a jaw crusher of a compression type primary crusher. The compression-type primary crusher 9 crushes the concrete lump, the asphalt lump, and the like of construction waste that is sent out from the grizzly type sieving and metering feeder 8.
Reference numeral 11 denotes a high-quality excavated hopper. The hopper 11 is charged with high-quality excavated residual soil (type 3 or higher of the soil classification standard of the Ministry of Land, Infrastructure, Transport and Tourism) and defective residual soil of 70 mm or less stored in the curing stock S3 of FIG.

Reference numeral 12 denotes a pan conveyor type quantitative feeder for sending out excavation residual soil of the hopper 11.
13 is a grizzly vibratory sieve.
The grizzly vibratory sieve 13 screens the excavated soil fed from the bread conveyor type quantitative feeder 12 into one having a particle size of 80 mm or less and the above. 10 is a lime silo for storing lime.
Reference numeral 101 denotes a rotary quantitative feeder that sends out lime from the lime silo 10. The rotary type quantitative feeder 101 can adjust the amount of lime delivered from the lime silo 10 by changing its rotational speed.
14 is a magnetic separator. The magnetic separator 14 includes a high-quality excavated residual soil having a particle size of 80 mm or less, which has been screened by the grizzly-type vibrating sieve 13, and a concrete lump of construction waste having a certain size or less, which has been screened by the grizzly-type sieve metering feeder 8. Then, the magnetic metal such as the concrete lump of the construction waste crushed by the primary crusher 9 and the iron pieces in the lime silo 10 added with the lime is removed.
Reference numeral 15 denotes a vibration sieve. The vibration sieve machine 15 is a mixture of excavated soil from which metal such as iron pieces sent out from the magnetic separator 14 is removed, a crushed material such as a concrete lump of construction waste, and lime, with a particle size of 40 mm or less and above. Sift.

16 is a super impeller of an impact type secondary crusher. The impact-type secondary crusher 16 crushes again the excavated soil having a particle size of 40 mm or more, the concrete lump of construction waste, etc., screened by the vibration sieve 15 to a particle size of 40 mm or less.
Reference numeral 17 denotes an intermediate raw material hopper. In the intermediate raw material hopper 17, only those having a particle size of 40 mm or less of a mixture of excavated soil screened by the vibration sieve 15 and crushed material such as concrete lump of construction waste are intermediate between the roadbed material and the tubular material described later. Retained as material.
Reference numerals 18 and 19 denote belt-type quantitative feeders for feeding the intermediate raw material held in the intermediate raw material hopper 17, respectively.
Reference numeral 20 denotes a multistage vibrating screen. The multistage vibratory sieve 20 is a multistage vibratory sieve having an upper stage with a 30 mm mesh sieve, a middle stage with a 20 mm mesh sieve, and a lower stage with a 7 mm mesh sieve.
S8 is a stock yard that holds the intermediate material remaining in the 30 mm mesh sieve of the multistage vibratory sieve 20, and 23 is the first that holds the intermediate material remaining in the 20 mm mesh sieve of the multistage vibratory sieve 20. An intermediate hopper 24 is a second intermediate hopper that holds the intermediate material remaining in the 7 mm mesh sieve of the multistage vibratory sieve 20, and 25 is an intermediate material that has passed through the 7 mm mesh sieve of the multistage vibratory sieve 20. A third intermediate hopper that holds

Reference numeral 21 denotes a belt-type quantitative feeder that distributes and feeds the intermediate raw material that has passed through the 20 mm mesh of the multistage vibrating screen 20 to the second intermediate hopper 24 and the stock yard S6.
Reference numeral 22 denotes a belt type quantitative feeder that distributes and feeds the intermediate raw material that has passed through the 7 mm mesh of the multistage vibrating screen 20 to the third intermediate hopper 25 and the stock yard S5.
29 is a lime silo for storing lime.
Reference numeral 291 denotes a rotary quantitative feeder for feeding lime from the lime silo 29. The rotary type quantitative feeder 291 can adjust the amount of lime fed from the lime silo 29 by changing its rotational speed.
Reference numeral 26 denotes a first belt-type quantitative feeder that sends out the intermediate raw material held in the first intermediate hopper 23. Reference numeral 27 denotes a second belt-type quantitative feeder for sending out the intermediate raw material held in the second intermediate hopper 24. Reference numeral 28 denotes a third belt type quantitative feeder for sending out the intermediate raw material held in the third intermediate hopper 25.
Reference numeral 30 denotes an intermediate raw material fed from the first belt-type quantitative feeder 26, the second belt-type quantitative feeder 27, and the third belt-type quantitative feeder 28, and lime sent from the rotary-type quantitative feeder 291. Is a mixing machine.
31 is a moisture adjuster.
S7 is a stock yard that holds the manufactured upper layer roadbed material.

The operation of the excavation residual soil reforming plant including the poor residual soil of the present invention configured as described above will be described as follows.
Ascongala hopper 7 is filled with concrete lump of construction waste, asphalt lump, and defective soil of 70 mm or more stored in curing stock S2 of FIG.
The ratio of the concrete block and the asphalt block of the ascongala hopper 7 is arbitrary, it is not always necessary to add both, and only one of them can be used.
Concrete lumps, asphalt lumps of construction waste stored in the ascongala hopper 7 and unsatisfactory residual soil of 70 mm or more are transported by the grizzly-type sieving meter feeder 8 to a certain size or larger. Those that are sifted and below a certain size are added to the magnetic separator 14.
A concrete lump or asphalt lump of construction waste of a certain size or more sent from the grizzly type sieving quantitative feeder 8 is added to the compression primary crusher 9 and crushed and then added to the magnetic separator 14.
High quality excavated residual soil (type 3 or more of the soil classification standard of the Ministry of Land, Infrastructure and Transport ordinance) fed into the high quality residual hopper 11 is sent out by the bread conveyor type quantitative feeder 12 and the particle size is 80 mm or less. Those having a diameter of 80 mm or less are added to the magnetic separator 8, and those having a diameter of 80 mm or more are stored in the stock S 4 and then put into the ascongaller hopper 7.

The lime of the lime silo 10 is added to the magnetic separator 14 by the rotary quantitative feeder 101.
The amount of lime added to the magnetic separator 14 is adjusted by changing the rotational speed of the rotary metering feeder 101. The amount of lime added is adjusted by the characteristics of the excavated soil, and it is about 3% of the excavated soil and the concrete lump of construction waste, etc. At most, it is adjusted at a mixing ratio of 5% or less.
The magnetic separator 14 includes a high-quality excavated residual soil having a particle size of 80 mm or less, which has been screened by the grizzly-type vibrating sieve 13, and a concrete lump of construction waste having a certain size or less, which has been screened by the grizzly-type sieve metering feeder 8. Then, a concrete lump of construction waste crushed by the primary crusher 9 and magnetic metals such as iron pieces in the lime silo 10 added with lime are removed and added to the vibration sieve 15.
The vibration sieving machine 15 screens a mixture of excavated soil from which metals such as iron pieces have been removed, a crushed material such as a concrete lump of construction waste, and lime into a particle size of 40 mm or more and the following, 40 mm or less Those of 40 mm or more are added to the impact type secondary crusher 16. The impact-type secondary crusher 16 crushes particles having a particle size of 40 mm or more and returns them to the vibration sieve 15 again.
The intermediate raw material having a particle size of 40 mm or less held in the intermediate raw material hopper 17 is sent out to the multistage vibratory sieve machine 20 by the belt type quantitative feeder 18, and the road yard stock yard S5 by the belt type quantitative feeder 19. Sent out.

The multistage vibratory sieve 20 screens an intermediate raw material having a particle diameter of 40 mm or less, which is held by the intermediate raw material hopper 17 sent out by the belt-type constant quantity feeder 18, into four kinds of intermediate raw materials.
The multistage vibratory sieve 20 sends the 40-30 mm particle size intermediate material remaining in the 30 mm mesh sieve to the stockyard S8, and the 30-20 mm particle size intermediate material remaining in the 20 mm mesh sieve is the first. The first intermediate hopper 23 is charged, and the 20-7 mm particle size intermediate material remaining on the 7 mm mesh screen is distributed to the second intermediate hopper 24 and the stock yard S6 and fed to a belt type quantitative feeder. The intermediate raw material having a particle diameter of 7 mm or less that has passed through the 7 mm mesh sieve is distributed to the third intermediate hopper 25 and the road yard stock yard S5 and fed into a belt-type quantitative feeder.
The intermediate raw material intermediate material having a particle size of 30-20 mm held in the first intermediate hopper 23 is added to the mixer 30 by the first belt-type quantitative feeder 26, and 20 held in the second intermediate hopper 24. The intermediate raw material having a particle size of -7 mm is added to the mixer 30 by the second belt-type fixed feeder 27, and the intermediate raw material having a particle diameter of 7 mm or less held in the third intermediate hopper 25 is the third belt type It is added to the mixer 30 by the fixed amount feeder 28.
The intermediate raw materials classified into the above three types are mixed at a predetermined ratio by adjusting the speeds of the first to third belt type constant quantity feeders 26-29.
The lime fed from the lime silo 29 by the rotary quantitative feeder 291 is added to the mixer 30.
The mixture of the intermediate raw material and lime mixed at a predetermined ratio by the mixer 30 is sprayed with water by the moisture adjuster 31 to determine the moisture content of the mixture. The moisture content ratio ω is 5 to 13% and the wet density ρt is 1.8. The upper layer roadbed material is obtained by adjusting to the range of ~ 2.1.

The mixing ratios of the intermediate raw material held in the first intermediate hopper 23, the intermediate raw material held in the second intermediate hopper 24, and the intermediate raw material held in the third intermediate hopper 25 are respectively the first belt. It is adjusted by adjusting the speeds of the formula constant quantity feeder 26, the second belt type constant quantity feeder 27, and the third belt type constant quantity feeder 28. This mixing ratio is controlled so as to fall within the particle size distribution defined by the desirable quality (upper roadbed) of the aggregate used for the lime stabilization treatment defined in the pavement design and construction guidelines established by the Japan Road Association shown below.
The intermediate raw material fed from the first belt type quantitative feeder 26, the second belt type quantitative feeder 27, and the third belt type quantitative feeder 28 and the lime fed from the rotary quantitative feeder 291 are mixed. 30 is mixed and the roadbed material is manufactured and held in the stock S7.
The components of the roadbed material produced by the plant of the present invention are as follows.
Concrete crushed material 0% -25%
Asphalt lump crushed material 0% -25%
Construction soil 70% -97%
Stabilized lime 5% or less Moisture content Moisture content ω 5-13%, wet density ρt 1.8-2.1

Because the roadbed material produced by the roadbed material manufacturing plant of the present invention is added with lime as a stabilizing material,
* Due to the hydration reaction, lime and water react, and the moisture content evaporates due to the heat of the hydration reaction, reducing the moisture content of the improved soil.
* By pozzolanic reaction, lime reacts with alumina and silicon in the earth and sand to form compounds such as calcium aluminate and calcium silicate, and unites the earth and sand.
* Due to the carbonation reaction, part of the lime reacts with carbon dioxide gas to form calcium carbonate, increasing the strength of the soil.
* By ion exchange reaction, fine clay particles are aggregated to make it easier to compact the soil.
Therefore, the characteristics as an upper layer roadbed material are greatly improved.
The upper roadbed material produced by the plant of the present invention has the characteristics that the particle size is uniform and the moisture content is constant, so that it is easy to compact and easy to compact, and has excellent mechanical strength. Therefore, reduction of material cost and construction cost can be realized by using this.

Usually, when the intermediate raw material having a particle size of 40 mm or less, which is accumulated and held in the intermediate raw material hopper 17 as a result of processing the excavated soil, is screened into the above four types of particle sizes, the particle size is 30-20 mm. In comparison, the ratio of intermediate raw materials having a particle size of 20 mm or less increases.
In order to stabilize the quality of the upper layer roadbed material, an intermediate raw material with a particle size of 30-20 mm and an intermediate raw material with a particle size of 20-7 mm and a particle size of 7 mm or less are mixed in a predetermined ratio. In many cases, intermediate raw materials having a particle size of 20 mm or less are collected.
40-30mm intermediate raw materials and 20mm or less intermediate raw materials that are not used in the manufacture of roadbed materials are stored in the stock yards S5, S6, S8 and used for the manufacture of roadbed materials or tube winding materials that have little restrictions on particle size distribution. Is done.
In order to specially manufacture the lower roadbed material, the 30 mm mesh screen of the multistage vibrating screen 20 of the above plant is removed and an intermediate raw material having a particle size of 40-30 mm is also fed into the first intermediate hopper 23. Is implemented.

FIG. 3 is an explanatory diagram showing a configuration of a plant that manufactures a pipe protective material using an intermediate material produced by the plant of FIG. 2 and stored in the stockyard S5.
In FIG. 3, 32, 35, 39 and 41 are first, second, third and fourth material hoppers, respectively. Reference numerals 33 and 36 denote trough type quantitative feeders for feeding the materials of the first and second material hoppers 32 and 35, respectively, and reference numerals 40 and 42 denote belt types for feeding the materials of the third and fourth material hoppers 39 and 41, respectively. It is a fixed quantity feeder.
Reference numerals 34 and 38 denote vibration sieves each having a 7 mm mesh. Vibrating screen machines 34 and 38 and the surface is less structure material adheres to the network employing a web of harp screen not horizontal from entering the flow direction of the sieved material, nets by compressed air operation pressure 5-10Kg / cm ² It is equipped with a cleaning system that relieves tension and removes deposits.
The vibration sieves 34 and 38 screen a mixture of lime having a size of 40 mm or less and excavated soil and a concrete lump of construction waste, etc., stocked in the stock yard S5 into those having a particle size of 7 mm or less.
37 is an impact type high-speed crusher. The impact type high-speed crusher 37 crushes by repeated impact between an impact blade attached to a rotor that rotates at high speed and a repulsion plate, and has a function of crushing to about 7 mm.
The impact type high-speed crusher 37 crushes excavated soil having a particle size of 7 mm or more and a concrete lump of construction waste, etc., screened by the vibration sieve device 34 to reduce the particle size to 7 mm or less.
43 is a mixture that mixes excavated soil having a particle size of 7 mm or less, which is screened by the vibration sieves 34 and 38 held by the third and fourth material hoppers 39 and 41, and a material such as a concrete lump of construction waste. Machine. S9 is a stockyard for storing the manufactured tube protection material, and S10 is a stockyard for storing a third material that is not mixed in the tube protection material.

The operation of the manufacturing plant of the pipe protection material configured as above will be described as follows.
The intermediate material having a particle size of 40 mm or less stored in the stock yard S5 is put into the first material hopper 32 and fed into the vibrating screen machine 34 by the trough-type fixed supply machine 33.
The reason why the mesh of the vibrating screen 34 is set to 7 mm is as follows.
Natural sand used as a conventional pipe protective material has a particle size of about 2.0 to 0.5 mm, and therefore has high water permeability and good workability, but has almost no strength.
On the other hand, most of excavated soil is soil, and its particle size is much finer than sand, but if there is much finer particle, the fluidity increases when it contains water and becomes muddy. Therefore, the workability and water resistance are poor, and the function as a pipe protective material is insufficient. For this reason, in order to include as large a particle as possible in the pipe protective material, concrete lumps and asphalt lumps of construction waste are added to the excavated soil.
In the case of waterworks or the like, a polyethylene sleeve is often wound around the pipe as a protection of the pipe, but it has been found that if the particle size of the pipe protective material is too large, the sleeve is damaged and broken. Furthermore, in construction at the construction site, after pipe laying is completed, pipe protection material is put around the pipe and rolled and compacted, but if the particle size of the pipe protection material is too large, There is a risk that the pipe protective material does not spread sufficiently to the lower surface and the like, and not only does the pipe protective function not perform sufficiently, but also leads to land subsidence at the pipe burial site.

In order to solve such a problem, various tests were conducted by changing the maximum particle size of the tube protective material particles. As a result, it was found that the maximum particle size of the tube protective material particles was 7 mm. The 34 mesh was set to 7 mm.
The mixture having a particle size of 7 mm or less that has been screened by the vibration sieve 34 is stored in a third material hopper 39.
On the other hand, the mixture having a particle size of 7 mm or more, which has been screened by the vibration sieve machine 34, is put into the second material hopper 35, and sent to the crusher 37 by the trough type quantitative feeder 36 to be crushed.
The material crushed by the crusher 37 is added to the vibration sieve 38, and a mixture having a particle size of 7 mm or less is selected.
The mixture having a particle size of 7 mm or less that has been screened by the vibration sieve 38 is held by the fourth material hopper 41. On the other hand, the mixture having a particle size of 7 mm or more screened by the vibration sieve 38 is sent again to the crusher 37 through the second material hopper 35 and the trough-type quantitative feeder 36 and is crushed.
The 7mm mesh screen of the vibrating screens 34 and 38 has a structure with few surfaces on which the raw material adheres to the net using a harp screen mesh, but in order to prevent clogging, it is compressed with an operating air pressure of 5-10Kg / cm2. Air purge with air is performed.

Both the mixture held in the third material hopper 39 and the fourth material hopper 41 are materials having a particle size of 7 mm or less. However, the mixture held in the third material hopper 39 includes a raw excavation soil. And the soil that was mixed in the concrete lumps and asphalt lumps of construction waste. On the other hand, the mixture held in the fourth material hopper 41 is a material obtained by pulverizing the excavated soil from which soil is removed 7 mm or more, the concrete lump of construction waste, and the asphalt lump to 7 mm or less. Has a structure close to natural sand, without soil.
The mixture held in the third material hopper 39 and the fourth material hopper 41 is added to the mixer 43 via the belt type quantitative feeders 40 and 42, respectively, and mixed at a predetermined ratio to produce a tube protective material. And stored in the stockyard S9.
The mixing ratio of the mixture of the third material hopper 39 and the fourth material hopper 41 is such that the soil mixed in the pipe protection material is constant while observing the conditions of the raw material excavated soil, construction waste concrete lumps and asphalt lumps. The weight ratio is set to a ratio of about 1: 1 to 3: 1.
When the ratio of soil contained in the excavated soil of the raw material, the concrete lump of construction waste, and the asphalt lump is large, the material of the third material hopper 39 that is not mixed in the pipe protection material may remain. The material of the third material hopper 39 having a large ratio can be stored in the stock yard S10 and used as culture soil for growing plants by adjusting the pH value.

The components of the pipe protective material produced by the pipe protective material production plant of the present invention are as follows.
Concrete lumps of construction waste 0% to 25% Asphalt lumps 0% to 25% Excavated soil 70% to 97%, lime of stable treatment material 5% or less.
In addition, a mixture of roof tiles or the like can be used for the concrete lump of construction waste.
Since the pipe protective material produced by the pipe protective material production plant of the present invention is added with lime as a stabilizing treatment material, the effect of making fine clay particles agglomerated and making the soil easy to compact is obtained. Therefore, the characteristics as a pipe protective material are greatly improved.
Since the pipe protective material produced by the pipe protective material production plant of the present invention contains soil having a particle size larger than 2.0 mm and a soil particle having a particle size smaller than 0.5 mm, the rolling pressure is reduced. It is easy to compact and easy to compact, and has excellent mechanical strength. Therefore, it is possible to maintain the strength of the roadbed even when the depth of the pipe is about 60cm. Since the polyethylene sleeve used as the protection can be stably protected without being damaged, the use of this can reduce the material cost and the construction cost.
The pipe protection material production plant of the present invention improves the recyclability of excavated soil containing defective residual soil to the same quality as the backfill material of pipe protection materials such as conventional sand, so that the waste is pipe protected. It is effectively used as a material.

According to the present invention, excavated soil containing clay-like defective soil containing a large amount of water that has been discarded in the designated waste disposal site for residual soil, and a concrete lump of construction waste that has been treated as industrial waste, Asphalt blocks can be reprocessed as roadbed materials and the like, and the reuse rate can be dramatically increased.
This eliminates the need to transport the waste to a designated waste disposal site for disposal, and reduces the need to collect crushed stones from distant quarries, etc. Since carbon dioxide is also reduced, the carbon dioxide emitted by the transport vehicle can be reduced.
FIG. 4 shows the carbon dioxide emitted by the transportation vehicle in the conventional road construction material transportation system and the carbon dioxide emitted by the transportation vehicle when the excavation soil reforming plant including the poor residual soil according to the present invention is adopted. This is a comparison of emissions.
In Fig. 4, it is assumed that the distance between the material yard of the road builder and the soil improvement plant of the present invention is 10 km, and the distance between the material yard, the remaining soil disposal site, and the quarry is 10 km, respectively. This is the amount of carbon dioxide emitted.
For this calculation, the formula of the Environmental Performance Evaluation Method Study Committee of the Logistics System Association of Japan and the Logistics Environment Conference was used, and the coefficient of 0.178 was the data of the 2002 National Land Transportation White Paper.
As is clear from FIG. 4, even when the distance between the road yard's material storage, the soil improvement plant of the present invention, the residual soil disposal site and the quarry is assumed to be equal, the soil improvement plant of the present invention is adopted. Shows that it is possible to reduce 33.3% of carbon dioxide emissions from transport vehicles compared to conventional systems.
As is clear from the above explanation, the present invention contributes to the prevention of natural destruction and resource depletion by collecting aggregates for road construction, and also has the effect of making up for a serious shortage of waste disposal sites. In addition to this, since the transportation cost of excavated earth and sand is saved, various causes of environmental destruction caused by the current road repair can be solved simultaneously.

The present invention can be used in construction industries such as roads, water supply construction, and sewerage.

It is a figure which shows the structure of the part of the pre-processing process of the defective residual soil of the excavation soil reforming plant containing the defective residual soil of this invention. It is a figure which shows the structure of the process part which reproduce | regenerates the excavation residual soil of the reforming plant of the excavation residual soil containing the defective residual soil of this invention to a roadbed material. It is explanatory drawing which shows the structure of the plant which manufactures a pipe | tube protective material using the intermediate raw material produced by the plant of FIG. It compares the amount of carbon dioxide emitted by a transport vehicle when the conventional road construction material transport system and the excavated soil reforming plant including defective residual soil according to the present invention are employed.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Elliptical disk screen 2 ... Hopper into which defective soil remains
S1 ... Stockyard for temporarily stocking defective soil over 70mm 6 ... Mixing tank
S2: Stock yard of poor residual soil of 70 mm or more to which improved material is added 3 ... belt type quantitative feeder 4 ... improved material silo 41 ... rotary quantitative feeder 5 for feeding improved material ..Mixers
S3: Stock yard of defective residual soil of 70 mm or less mixed with improved material 7 ... Ascongala hopper 8 ... Grizzly type sieving metering feeder 9 ... Compressive primary crusher 11 ... High quality excavation residual hopper 12 ... Pan conveyor type quantitative feeder 13 ... Grizzly type vibrating sieve 10 ... Lime silo 101 for storing lime ... Rotary type quantitative feeder 14 ... Magnetic separator 15 ... Vibration sieve 16 ... Impact-type secondary crusher 17 ... Intermediate raw material hoppers 18, 19 ... Belt-type quantitative feeder 20 ... Multi-stage vibratory sieve
S8: Stock yard 23 for holding the intermediate raw material remaining on the 30 mm sieve First intermediate hopper 24 for holding the intermediate raw material remaining on the 20 mm sieve The intermediate raw material remaining on the 7 mm sieve Second intermediate hopper to hold 25... Third intermediate hopper 21 to hold intermediate raw material that has passed through a 7 mm sieve, 22... Belt-type metering feeder 29. Lime silo 291 to store lime ..Rotary type quantitative feeders 26, 27, 28 ... Belt type quantitative feeders 30 ... Mixers
31 ... Moisture adjuster
S7... Stockyard 32, 35, 39, 41... Material hopper 33, 36... Trough type metering feeder 40, 42. 38 ... Vibrating sieve 37 ... Shock type high speed crusher 43 ... Mixer
S9: Stock yard for storing manufactured pipe protection materials
S10: Stock yard for storing a third material that is not mixed into the tube protection material

Claims (2)

An elliptical disk screen that screens the bad soil that needs to be pre-processed into 70 mm or larger and the following:
A first curing stock for storing defective soil of 70 mm or more screened by an elliptical disk screen and holding it for mixing with raw materials such as ascongala hoppers of an excavation soil treatment plant described later,
An improvement material silo that holds an improvement material to be added as a stable treatment material to defective soil of 70 mm or less screened by an elliptical disk screen,
A rotary type quantitative feeder that adjusts the amount of improved material sent out from the improved material silo,
A mixer that mixes the poor material of 70mm or less, which has been screened by an elliptical disc screen, with the improved material sent from the silo,
A second curing stock for storing the poor residual soil of 70 mm or less whose soil quality has been improved by mixing the improvement material by the mixer and holding it for mixing as excavated soil in the excavated soil treatment plant described later,
Concrete lumps of construction waste, asphalt lumps, ascongala hoppers that are fed with poor-quality residual soil of 70 mm or more stored in the first curing stock,
A grizzly sieving metering feeder that sifts over a certain size and the following while transporting the raw material stored in the ascongala hopper,
Compression-type primary crusher that crushes raw materials of a certain size or more sent out from a grizzly sieving metering feeder,
A high quality excavation surplus hopper into which the high quality excavation surplus soil and the poor residual soil of 70 mm or less stored in the second curing stock are input,
Pan conveyor type quantitative feeding machine that sends out the excavated residual soil of the excavated residual soil hopper,
A grizzly vibratory sieve that screens excavated soil delivered from a bread conveyor type quantitative feeder into one with a particle size of 80 mm or less and one with the above.
Lime silos that store lime,
Rotary type quantitative feeder that sends out lime from lime silo,
Lime is added to high-quality excavated soil with a particle size of 80 mm or less, which is screened by a grizzly-type vibrating screen, raw materials of a certain size or less, which are screened by a grizzly-type sieve metering feeder, and crushed by a primary crusher. A magnetic separator that removes magnetic metals such as iron pieces in silo lime,
Vibrating sieve machine that screens a mixture of excavated soil, raw material, raw material crushed material, and lime from which metal such as iron pieces sent out from a magnetic separator is removed, to a particle size of 40 mm or less
An impact type secondary crusher that crushes again a mixture of excavated soil having a particle size of 40 mm or more, a raw material, a crushed material of the raw material, and lime, which has been screened by a vibration sieve, to a particle size of 40 mm or less;
An intermediate raw material hopper for holding as an intermediate raw material a particle size of 40 mm or less of a mixture of excavated soil, raw material, raw material crushed material and lime screened by a vibration sieve machine,
A belt-type metering feeder that feeds the intermediate material held in the intermediate material hopper,
A multistage vibratory sieve having a 30 mm mesh sieve on the top, a 20 mm mesh sieve on the middle, and a 7 mm mesh sieve on the bottom,
A stock yard that holds the intermediate raw material remaining in the 30 mm mesh sieve of the multistage vibratory sieve machine,
A first intermediate hopper that holds the intermediate raw material remaining in the 20 mm mesh sieve of the multistage vibratory sieve machine;
A second intermediate hopper that holds the intermediate raw material remaining in the 7 mm mesh sieve of the multistage vibrating screen,
A third intermediate hopper that holds the intermediate raw material that has passed through the 7 mm mesh sieve of the multistage vibratory sieve machine;
A belt-type quantitative feeder that distributes and feeds the intermediate raw material that has passed through the 20 mm mesh of the multistage vibratory sieve machine to the second intermediate hopper and stock yard,
A belt-type quantitative feeder that distributes and feeds the intermediate raw material that has passed through the 7 mm mesh of the multistage vibratory sieve machine to the third intermediate hopper and stock yard,
Lime silos that store lime,
Rotary type quantitative feeder that sends out lime from lime silo,
A first belt-type metering feeder for feeding the intermediate material held in the first intermediate hopper;
A second belt-type metering feeder for feeding the intermediate raw material held in the second intermediate hopper;
A third belt-type metering feeder for feeding the intermediate material held in the third intermediate hopper;
A mixer that mixes the intermediate raw material fed from the first belt-type metering feeder, the second belt-type metering feeder and the third belt-type metering feeder, and the lime fed from the rotary metering feeder;
A drilling soil reforming plant that contains poor-quality residual soil that is obtained by recycling drilling soil equipped with An elliptical disk screen that screens the bad soil that needs to be pre-processed into 70 mm or larger and the following:
A first curing stock for storing defective soil of 70 mm or more screened by an elliptical disk screen and holding it for mixing with raw materials such as ascongala hoppers of an excavation soil treatment plant described later,
An improvement material silo that holds an improvement material to be added as a stable treatment material to defective soil of 70 mm or less screened by an elliptical disk screen,
A rotary type quantitative feeder that adjusts the amount of improved material sent out from the improved material silo,
A mixer that mixes the poor material of 70mm or less, which has been screened by an elliptical disc screen, with the improved material sent from the silo,
A second curing stock for storing the poor residual soil of 70 mm or less whose soil quality has been improved by mixing the improvement material by the mixer and holding it for mixing as excavated soil in the excavated soil treatment plant described later,
Concrete lumps of construction waste, asphalt lumps, ascongala hoppers that are fed with poor-quality residual soil of 70 mm or more stored in the first curing stock,
A grizzly sieving metering feeder that sifts over a certain size and the following while transporting the raw material stored in the ascongala hopper,
Compression-type primary crusher that crushes raw materials of a certain size or more sent out from a grizzly sieving metering feeder,
A high quality excavation surplus hopper into which the high quality excavation surplus soil and the poor residual soil of 70 mm or less stored in the second curing stock are input,
Pan conveyor type quantitative feeding machine that sends out the excavated residual soil of the excavated residual soil hopper,
A grizzly vibratory sieve that screens excavated soil delivered from a bread conveyor type quantitative feeder into one with a particle size of 80 mm or less and one with the above.
Lime silos that store lime,
Rotary type quantitative feeder that sends out lime from lime silo,
Lime is added to high-quality excavated soil with a particle size of 80 mm or less, which is screened by a grizzly-type vibrating screen, raw materials of a certain size or less, which are screened by a grizzly-type sieve metering feeder, and crushed by a primary crusher. A magnetic separator that removes magnetic metals such as iron pieces in silo lime,
Vibrating sieve machine that screens a mixture of excavated soil, raw material, raw material crushed material, and lime from which metal such as iron pieces sent out from a magnetic separator is removed, to a particle size of 40 mm or less
An impact type secondary crusher that crushes again a mixture of excavated soil having a particle size of 40 mm or more, a raw material, a crushed material of the raw material, and lime, which has been screened by a vibration sieve, to a particle size of 40 mm or less;
An intermediate raw material hopper for holding as an intermediate raw material a particle size of 40 mm or less of a mixture of excavated soil, raw material, raw material crushed material and lime screened by a vibration sieve machine,
Vibrating sieve machine with a 7 mm mesh that screens the intermediate raw material of the intermediate raw material hopper and screens it into two types of raw materials with a particle size of 7 mm or more and 7 mm or less.
A third material hopper into which a raw material having a particle size of 7 mm or less screened by a vibration sieve is charged;
A secondary impact crusher that crushes again the raw material of 7 mm or more screened by the vibration sieve machine and adds it to the vibration sieve machine having a 7 mm mesh;
A fourth material hopper into which a raw material obtained by re-smashing a raw material of 7 mm or more is charged;
A belt-type metering feeder that feeds the materials held in the third material hopper and the fourth material hopper at a predetermined ratio, respectively.
A mixer that mixes materials sent by a belt-type metering feeder,
And a drilling soil reforming plant containing defective residual soil in which a raw material having a particle size of 7 mm or less is obtained as a pipe protective material.

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