JP6166801B2 - Method for assembling surplus kon, method for producing recycled material thereby, and device for assembling the same - Google Patents

Description

  The present invention relates to a method for aggregating surplus kon, a method for producing a recycled material thereby, and an aggregating apparatus used therefor.

  Most of the ready-mixed concrete is manufactured with a specific composition according to the application, and those that are judged to affect the hardened concrete according to the fresh property test results of the ready-mixed ready-to-place are rejected and not used at that time. . The fresh property of ready-mixed concrete refers to the state of concrete that is in the state from immediately after mixing ready-mixed to the setting and hardening, but it is mainly used as a term to evaluate workability on site. In many cases, the tests performed in the field are determined by a slump test or an air amount test.

  The ready-mixed concrete used at the construction site is manufactured at the ready-mixed factory and delivered to the site using a ready-mixed car. Generally, it is processed back to the ready-mix factory.

  Such surplus cooked corn is generated not only in the ready-mixed concrete factory but also in the concrete product factory, and is rarely used as it is, and is generally processed after being brought back to the ready-mixed factory.

  When processing surplus ready-mixed concrete that has been brought back to the ready-mixed factory (remaining ready-mixed or unneeded ready-mixed concrete at construction sites or concrete product factories, etc.), it is added to the surplus ready-mixed concrete, solids, slurry, and solids (gravel, Crushed stone, sand, etc.), the slurry is treated with water, the solid content that can be used is used, and the rest is industrial waste. Moreover, after surplus raw concrete is hardened, it may be crushed and disposed of as concrete trash, or may be disposed of by other contractors.

Uncured surplus waste (fluidized state) is treated as inorganic sludge in industrial waste, but when it is cured, it is treated as concrete waste (concrete with a strength of 8 N / mm ² or more). Yes.

An example of effective use of surplus raw concrete is to aggregate the residual concrete and use it as roadbed material, soil improvement material, etc., for example, in Patent Document 1 below, it is put into the remaining ready-mixed concrete A residual con treatment material, comprising: a package formed in a bag shape with water-soluble paper; and a powdery or granular water-absorbing polymer encapsulated in the package The remaining control material is disclosed.
Utility Model Registration No. 3147832

  In this patent document 1, when the remaining raw material processing material is thrown into the surplus raw material, and then the surplus raw material is stirred by rotating the drum of the concrete mixer of the agitator car, cement and water-absorbing material are used around the aggregate as a core. A layer of a mixture with the polymer is formed to form a dumpling-shaped granulated body. This granulated body is then hardened by hardening of the cement with moisture. The cured granule thus obtained can be used as a roadbed material as it is.

  As the water-absorbing polymer in Patent Document 1, for example, one kind of polymer such as acrylic acid, acrylate, methacrylate, acrylamide, vinyl alcohol, vinyl pyrrolidone, styrene sulfonate, and maleic anhydride, or Two or more types of copolymers are used.

  In Patent Document 1, when a residual component treatment material is introduced into the residual component, the package formed of water-soluble paper dissolves or disperses in water in the residual component, and the water-absorbing polymer enclosed in the package becomes the residual component. Contact with. When the remaining container is stirred, the water-absorbing polymer mixed with the remaining container absorbs the water in the remaining container and swells to form a gel having a three-dimensional network structure. The cement paste is entangled, and the aggregate is taken into the network structure of the water-absorbing polymer and cement.

  When the remaining components are put into the remaining components in the drum of the agitator car that has been brought back to the concrete manufacturing site, and the remaining components are mixed by stirring, a mixture layer of gel and cement of the water-absorbing polymer Is grown and granulated with an aggregate as a core, and is described as an approximately spherical dumpling-shaped granulated body.

The following Patent Document 2 has been proposed as a fresh concrete flocculant and a fresh concrete treatment method for aggregating surplus fresh concrete in a drum and suppressing a decrease in fluidity of fresh concrete newly put into the drum. A polymer absorber capable of absorbing water selected from the group consisting of polyacrylic, polyvinyl alcohol, polysaccharides, and proteins, as a dispersoid, for example, a polymer absorber such as an organic solvent or an aqueous salt solution Mix the ready-mixed flocculant with surplus ready-mixed concrete and discharge it.
JP 2009-126761 A

  In this Patent Document 2, as the ready-mixed concrete flocculant, a ready-mixed concrete flocculant (trade name: Tunnel A3-L, manufactured by Sumitomo Osaka Cement Co., Ltd.) having a polyacrylamide polymer absorbent as a dispersoid in a dispersion medium is used. .

The following Patent Document 3 was proposed as a new method for reusing residual fresh concrete that converts uncured residual concrete into granular material in a short time without generating waste. It is intended to add an absorbent polymer to an uncured fresh cement composition.
Japanese Patent No. 5813131

  In Patent Document 3, the quick setting accelerator is selected from substances that form sodium silicate or calcium aluminate hydrate, and the superabsorbent polymer is ionic SAP, which is particularly modified with acrylic acid and linear. And based on polyacrylamide having both crosslinked structures.

Dose of quick-promoter, concrete 1m ³ 0.3~50kg / m ³ as the dose per, preferably in the range of 0.6~20kg / m ^3, more preferably 0.8~15kg / m ^3.

Dose of superabsorbent polymer concrete 1m ³ 0.05~10kg / m ³ as the dose per, and preferably from 0.1 to 5 kg / m ^3, more preferably 0.15~2kg / m ^3.

The following Patent Document 4 was proposed as a raw concrete agglomerated material capable of agglomerating uncured concrete composition and cement composition such as surplus raw concrete (residual concrete), and has a weight average molecular weight of 1,100. Ten to twenty-two million anionic polyacrylamide polymer (formula I) is used as a fresh concrete flocculant.
JP 2014-181147 A

  Although Patent Documents 1 to 4 are based on the principle of using an agitator vehicle, there are the following problems.

  Since the surplus cooker has a smaller volume than that at the time of shipment due to remaining use, as shown in FIG. 21, the position of the surface of the surplus cooker inside the agitator mounted with the live cooker is below the position at the time of shipment. When the surplus kon is put into the agitator and agitated, the agitator is rotated.

  However, since the spiral blades are partly attached to the side wall of the drum, the agitator is agitated while keeping the surface position as shown in FIG. The

  And by adding the aggregating agent, the surplus corn loses the fluidity around the part where the aggregating agent touches and the adhesive force increases, so that it remains attached to the drum side wall as shown in FIG. 22B. May be rotated.

This varies the rotation speed of the drum, generally the drum rotation speed at the time of post-added concrete admixture is ready for about 10min ^-1 ~18min ^-1, centrifugal force acts.

  Further, the drum side is made of steel and has an infinite number of fine scratches due to agitation with the raw material aggregate and the surface area is increased, so that the aggregate is easily attached.

  Such deposits can form large, hard blocks, require effort to drain and dispose, and are time consuming and costly.

  In Patent Document 3, in order to make up for such a drawback, it is necessary to use a quick setting accelerator together.

  Moreover, in patent document 4, when an anionic polyacrylamide type polymer compound is used as an aggregating agent for aggregating the ready-mixed concrete, if the molecular weight is too large, the agglomeration is not achieved and it is too small. When the mortar flow of the next batch is reduced, and when there is no ionicity, that is, when there is no anion part, it is said that no agglomeration is achieved. In particular, when the ionic strength (ratio of the anion portion) is too large, aggregation is not achieved, and when it is too small, the flow of the mortar of the next batch is lowered.

  Patent Document 4 shows that in Comparative Examples 1 and 2 in Table 2, the ionic strength (mol%) 26 or 23, the average molecular weight (× 10,000) 1,600, or 2,300 is “×” in the aggregated form. Thus, the ionic strength (mol%) is limited.

  Moreover, although patent document 1 and patent document 2 use what is used for the superabsorbent polymer granulated, workability | operativity is bad.

  An object of the present invention is to eliminate the inconvenience of the conventional example, and to agitate the surplus raw concrete that is fluidized in the agitator mounted on the raw concrete car without agitation with the agitator, and by applying it to the agitator after discharging. Troubles using the car can be avoided, and the surplus kon fluidized by systemization can be easily moved, transported, unloaded, loaded, crushed, classified, etc., and anionic When using polyacrylamide polymer compounds, it is possible to form agglomerates even if they have strong ionic properties, improve the aggregate classification process and workability that have been implemented, and water treatment An object of the present invention is to provide a method for aggregating surplus kon which can contribute to downsizing of facilities and the like, a method for producing reclaimed material thereby, and an aggregating apparatus used therefor.

The invention of claim 1, wherein for achieving the object, the excess raw configuration that fluidized within agitator mounted fresh concrete vehicles 1-shaft or two-shaft after discharged from the agitator, the rotational speed of the stirring device 100 min ^- An anionic polyacrylamide system (A-PAM) having a weight average molecular weight of 10 to 25 million and an anionic monomer of 25 to 100 mol%, which was emulsified in advance by applying to a continuous stirring apparatus of ¹ or more ) Is added as a main component and the amount of air gap is increased by the stirring device.

According to claim 1 Symbol placement of the present invention, without directly stirred agitator to the crumb of the excess raw configuration that fluidized within agitator mounted mixed concrete vehicles, the agitator by applying the stirring device after ejection Therefore, it is necessary to make efforts to form a large hard block as an adhering matter and to discharge and dispose of the block, and it is possible to avoid the trouble of using an agitator vehicle, which is a waste of time and an additional cost.

In addition, the rotation speed of the stirrer is 100 min. ^-1 By setting it as the above, it will consider the clogging phenomenon and shortening of stirring time.

  In addition, even if the anionic monomer has a strong ionicity such as 25 to 100 mol% anionic polyacrylamide (A-PAM) polymer aggregating agent, the amount of air gap can be increased by a stirrer. As it is possible, agglomeration can be realized reliably.

  Moreover, the anionic polyacrylamide-based (A-PAM) polymer aggregating agent is preliminarily emulsified, whereby the stirring time can be shortened and the working efficiency can be increased.

  The surplus kon immediately after agglomeration is in a state where it can be piled up with little drainage of moisture. Also, it is solidified by cement hydration over time (aggregation solidification), but because the gaps during aggregation remain, it is weak in strength and compared to the fracture strength of hardened concrete. Will be destroyed with much less strength.

  At the initial stage of aggregate formation, cement particles are also condensed by the aggregate formation agent. Cement has a different coagulation effect and takes in bound water. However, since the amount of the gap is large, part of the restraint water and free water remain as the pore water. With time, the water in the gap is vaporized and the air gap amount increases. In other words, the cement paste shows stronger adhesive strength with less moisture, but the unit volume mass becomes smaller because the air gap amount increases than the original surplus corn due to agglomeration, and the cement mass mixed per unit volume is It is running low.

  In other words, the concentration of cement paste is higher than the original surplus kon, but the total cement amount is reduced in wet density, so the cement mass per unit volume is small and the amount of air is large. I can say that.

  In the case of recovering aggregate from surplus raw concrete, the crushing strength after hardening becomes small, so the crushing work (reduction of equipment and energy costs) is facilitated by the amount of energy for destruction. In addition, it can be used as a roadbed material even in a state in which the aggregate is unclassified without classification.

In the present invention according to claim 2 , the anionic polyacrylamide type (A-PAM) polymer aggregating agent is added at a unit addition amount of 0.5 kg / m ³ to 5 kg / m per 1 m ³ of surplus kon. ^The gist is to be within the range of ³ .

According to the second aspect of the present invention, an appropriate amount of the polymer aggregating agent for providing the aggregated state is presented.

The present invention according to claim 3 is the volume of the surplus kon with a fine particle content of 0.15 mm or less selected from pulverized mineral, industrial bentonite, slag, clay mineral, etc. The present invention according to claim 4, wherein the unit addition amount per 1 m ³ is 0.5kg / m ³ or more, and the unit addition amount per 1 m ³ volume of surplus kon is added to the reclaimed sand in which particles of 1 mm or less are 40% or more in particle size distribution. The main point is to add 15 kg / m ³ or more.

According to the present invention described in claim 3 or claim 4 , the binder ability (adhesion performance) of the aggregating agent can be enhanced by adding fine particles, fine particles or regenerated sand.

The gist of the present invention described in claim 5 is that the stirring device for increasing the air gap amount of the surplus raw concrete is a continuous stirring device having paddle type blades.

According to the fifth aspect of the present invention, the stirring device for increasing the air gap amount of the surplus raw concrete is not a tilting type of gravity agitation like an agitator mounted on a raw concrete car, and the agitation entrains air. In order to make it easy, a continuous stirring device is used. By making the blade shape into a paddle type, reflowing can be suppressed by re-kneading and the stirring time can be shortened. The merits of using a continuous stirring device are as follows.
(1) Since there is continuity, it is a continuous operation even if there are a large number of agitator vehicles equipped with surplus kon, and it is suitable not only for the kon factory but also for processing surplus kon by intermediate processing. Since batch work is a single work, it is not suitable for such continuous work.
(2) By increasing the capacity of the raw-container quantitative feeder of the apparatus, it becomes possible to simultaneously process several surplus raw-containers equipped with several agitators.
(3) By automating the control described above, it is possible to consolidate surplus raw concrete and operate in a state close to unmanned operation.
(4) Since it becomes a continuous work, the processing work of the discharged aggregated raw concrete becomes easy.

The present invention according to claim 6 is a method for producing a recycled material by agglomeration of surplus kon, and the aggregated surplus kon produced according to claim 1 is selected from a trommel or a vibrating sieve immediately after the agglomeration. The gist is that the classification device of the classification device is divided into coarse particles and fine particles to obtain aggregates.

According to this invention of Claim 6, it can manufacture rapidly, without passing through the process of solidification of the aggregate as a recycled material by aggregation of surplus raw concrete.

The present invention according to claim 7 is a method for producing a recycled material by agglomeration of surplus kon, and the aggregated surplus kon produced according to claim 1 is solidified by hydration by cement and moisture in the surplus kon. Crush the solidified material and classify it into coarse particles and fine particles with a classifier such as a vibrating sieve to make a part of aggregate or backfill material or roadbed material (RC material). It is a summary.

According to this invention of Claim 7 , it solidifies by the hydration effect | action by the cement and water | moisture content in the surplus kon which aggregated the timing of making it a part of aggregate, a backfill material, or a roadbed material (RC material). After the solidified material is crushed and divided into coarse and fine particles through a classifier, the pre-solidification (immediate) and post-solidification processes are performed according to the timing over time. Is possible.

The present invention according to claim 8 is an agglomeration device used in the agglomeration method of surplus kon, the surplus kon fluidized in the agitator mounted on the unction car is discharged to a stirrer and emulsified in advance. In addition, an anionic polyacrylamide (A-PAM) polymer aggregating agent having a weight average molecular weight of 10 to 25 million and an anionic monomer of 25 to 100 mol% is added, and the stirring device is used. It is an agitation device used for a surplus kon aggregate agglomeration treatment method characterized by increasing the air gap amount, and is equipped with a surplus kon quantification feeder and a polymer aggregating agent addition device. To do.

According to the eighth aspect of the present invention, when surplus raw concrete is brought in with a raw concrete car, the discharge amount when discharging the raw concrete from the raw concrete car is not stable, and the amount of surplus raw food supplied is unstable. However, it is possible to stabilize the amount to be added to the continuous agitation device by equipping the surplus raw material quantification feeder and polymer aggregate agent addition device, and also adding the amount of aggregate agent and aggregation It becomes possible to stabilize the addition amount of fine particles and fine particles for improving the binder ability (adsorbability) of the agent, thereby realizing systemization.

The gist of the present invention described in claim 9 is that it is further equipped with an auxiliary material addition feeder.

According to the ninth aspect of the present invention, even when adding fine particles, fine particles or regenerated sand to increase the binder ability (adhesion performance) of the aggregating agent, it is added by equipping the auxiliary material addition feeder. The amount can be stabilized and systematization can be realized.

  As described above, the surplus kon agglomeration method of the present invention, the method for producing reclaimed material thereby, and the agglomeration apparatus used therefor easily move, transport, unravel, load, and load surplus corn. It is possible to facilitate operations such as crushing and classification, and in particular, it is possible to improve workability in the case of producing recycled aggregates by classifying surplus raw concrete.

  The present invention can avoid the trouble of using the agitator vehicle by aggregating the surplus raw concrete that is fluidized in the agitator mounted on the raw concrete vehicle without using the agitator and applying it to the stirring device after discharging. In addition, it is possible to easily move, transport, unravel, load, crush, classify, etc. surplus kon fluidized by systemization, and use anionic polyacrylamide polymer compounds In this case, agglomeration can be realized even with strong ionicity.

By combining several techniques of the present invention, the following advantages can be obtained.
(1) When surplus kon is processed, fluidity is lost by agglomeration, so loading with an excavator such as a backhoe, transportation by a dump truck, and transfer of a belt conveyor can be performed immediately.
(2) From the method of collecting and classifying surplus raw concrete in a raw concrete factory, etc., reducing the amount of slurry by applying a part of the agglomeration technology to RC production This makes it possible to reduce the size of water treatment and dehydration equipment. Profits from RC sales can also be expected.
(3) In a method in which surplus raw concrete is hardened into concrete and subjected to crushing, classification, and collecting aggregates, this technology is applied to solidify the surplus raw concrete so that the amount of fracture energy It becomes possible to suppress crushing work and downsizing of equipment.
(4) Furthermore, it is possible to classify immediately without waiting for the time until it hardens. Thereby, a crushing operation process is omitted.
(5) When surplus raw concrete is used for roadbed materials, etc., it can be used simply by solving the aggregated surplus raw concrete without the work of crushing after curing.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a flowchart showing the method for agglomerating surplus kon of the present invention. In the present invention, the agglomerated state is obtained by adding an aggregating agent to surplus kon and increasing the air gap amount by the stirring device 4. To get surplus kon.

  As shown in FIGS. 4 to 6, the agitation device 4 adds an aggregating agent to the surplus kon, and increases the air gap amount by the agitation device 4 to obtain the surplus kon in the aggregated state. The surplus raw concrete from the raw concrete vehicle 6 is stored in a hopper and supplied with a screw, and a quantification feeder 5 is provided to stabilize the supply amount by making it variable.

  At the subsequent stage of the quantification feeder 5, a stirring device 4 is provided to increase the air gap amount by stirring the surplus raw concrete.

  Moreover, the stirring apparatus 4 which is a grouping apparatus has the grouping agent addition apparatus 9 which can add a grouping agent continuously with the supply apparatus (pump) which can variably add the amount of grouping agents. Although not shown in FIG. 4, a pipe for supplying the aggregating agent is provided from the aggregating agent addition device 9 in the vicinity of the screw 1 (described later) of the stirring device 4.

  Furthermore, the aggregating agent addition device is equipped with an auxiliary material addition feeder 7 for adding reclaimed sand as an auxiliary material for increasing the binder ability of the aggregating agent to the surplus kon. Moreover, the fine particle part and the fine particle molecule | numerator for improving the binder ability of an aggregating agent may be added to surplus raw | mixed_stock by the feeder provided separately. In the figure, reference numeral 8 denotes a control panel for setting the operation and interlocking with the surplus raw material quantification feeder 5, the aggregating agent addition device 9, and the auxiliary material addition feeder 7 in the stirring device 4.

  First, the aggregating agent used in the present invention will be described. The aggregating agent used in the present invention is a polymer aggregating agent mainly composed of an anionic polyacrylamide (A-PAM). As used herein, the term “main component” means that an emulsified product is used as will be described later, and an emulsifier is added in advance to emulsification, which means that it is not purely A-PAM.

  The weight average molecular weight of A-PAM is in the range of 10 million to 25 million. Preferably it is 12 million-20 million, More preferably, it is 12 million-18 million. If it is lower than 10 million, the aggregate effect of the present invention cannot be obtained. If it is higher than 25 million, an appropriate aggregated state cannot be obtained.

  As an anionic monomer, it is the range of 25-100 mol%, Preferably it is 27-100 mol%, More preferably, it is 30-100 mol%. An anionic polyacrylamide polymer (A-PAM) polymer was obtained by hydrolyzing polyacrylamide with an alkali or the like, or obtained by copolymerizing an acrylamide monomer and an acrylic acid monomer. Is. As an anionic monomer used when producing A-PAM, in addition to acrylic acid, methacrylic acid, itaconic acid, maleic acid, p-carboxystyrene, acrylamide 2-methylpropane sulfonic acid, styrene sulfonic acid, etc. You may use together. The number of moles of the anionic monomer is in the range of 25 to 100 mol%, preferably 27 to 100 mol%, more preferably 30 to 100 mol%. In addition to acrylamide, copolymerizable nonionic monomers include N, N-dimethylacrylamide, vinyl acetate, acrylonitrile, methyl acrylate, 2-hydroxyethyl (meth) acrylate, diacetone acrylamide, N -Vinylpyrrolidone, N-vinylformamide, N-vinylacetamide, acryloylmorpholine and the like may be used in combination.

  As the anionic polyacrylamide (A-PAM) polymer aggregating agent, a pre-emulsified (liquefied) one is used. Since the emulsion is easy to adjust the molecular weight and the dispersibility of the aqueous solution is high, the form of a water-in-oil emulsion is adopted. Production of the water-in-oil emulsion is in accordance with conventional methods. That is, as described in JP-A-2014-117625, an ionic monomer or a nonionic monomer, or a mixture of an ionic monomer and a nonionic monomer is immiscible with water. An oily substance consisting of a hydrocarbon, an amount effective to form a water-in-oil emulsion, and at least one surfactant having HLB are mixed and stirred vigorously to form a water-in-oil emulsion, followed by polymerization. To manufacture.

The polymer aggregating agent mainly composed of an anionic polyacrylamide type (A-PAM) is added to surplus kon 0.5 to 5-5 kg / m ³ per 1 m ^{3 of} surplus kon.

As the agitation device 4 for increasing the air gap amount of the surplus raw concrete, as much as possible, avoid the one that is mainly a kneading and kneading type, such as a mixer for the production of raw concrete. A device that efficiently entrains air by stirring for a second is suitable, and a continuous stirring device is used.

The mixer (kneading equipment), which is called a forced twin-shaft type used in the production of ready-mixed concrete, has a rotating speed of 25 min ^-1 as know-how of mixer manufacturers in order to minimize air entrainment due to the rotation of the kneading blades. There are many cases where it is set to about 50 min ⁻¹ , but it is not suitable because rotation control is difficult and re-kneading fluidization is likely to occur.

  An example is shown in FIG. This is the B type of the uniaxial continuous stirring apparatus shown in Table 1 described later. The stirring device 4 includes a screw 1, a paddle 2, and a screw 3, and the screw 1 in the front stage supplies surplus raw material to the paddle 2, and the paddle 2 performs stirring. The paddle 2 has an angle for reducing the clogging phenomenon, and is discharged by the screw 3 after the paddle 2 is stirred.

  The length is 2 m, and the uniaxial continuous mixer A type shown in Table 1 is 2.4 m.

  FIG. 3 shows a deformation pattern of the arrangement of the uniaxial continuous mixer A type paddle 2 and the screws 1 and 3. In the example shown in the figure, the supply screw 1 for the surplus kon is commonly located at the front position of the paddle 2, but the discharge screw 3 is provided at the rear position of the paddle 2 (middle figure), A combination between the paddles 2 is also possible.

  The arrangement of the paddle 2 and the screws 1 and 3 varies depending on the properties of the agitated material and the agitation time. However, in the case of agglomeration, the paddle shape (for example, four blades or Two blades) are preferred. However, the angle and position of the paddle 2 are a factor that causes clogging of the surplus cooker that is continuously fed in, and thus the shape is taken into consideration. The casing diameter of the stirrer 4 is made not to be so large. For example, in the case of the uniaxial continuous stirrer B type, the casing diameter is within 550 mm.

In addition, the rotation speed is preferably set to 100 min ^-1 rpm or more from the clogging phenomenon and shortening of the stirring time. Preferably, it is 130 min ^{−1 to} 180 min ⁻¹ .

  The present invention improves the workability such as transfer and crushing of surplus raw-comb processing by forming agglomerates with a large amount of air (open cells) that are not fluid and poor in quality Is something that can be done.

  In the present invention, an anionic polyacrylamide-based (A-PAM) polymer having a coagulation action of polyacrylic acid as a main component, a weight average molecular weight of 10 million or more, and an anionic monomer of 25 mol% or more is used as surplus kon. Used as an aggregating agent to lose fluidity.

  FIG. 20 shows the amount of the aggregating agent added and the change in the slump value in the slump test for evaluating the workability of the ready-mixed rice.

  The slump value shown in FIG. 20 is indicated by an upper limit of 25 cm and a lower limit of 0 cm. The larger the fluidity, the closer to the upper limit value, and the smaller the value, the closer to the lower limit value. The same value as the upper limit. On the contrary, it becomes 0 cm in a state where there is no fluidity, and this is also not compared with the magnitude of the deformation amount, and is compared as a reference value.

According to this example, it can be seen that the fluidity is lost by increasing the addition amount of the aggregating agent. In Example (1), the aggregating agent addition amount is 1.5 kg / m ³ , and in Example (2), the slump value is zero at 2.5 kg / m ³ , indicating that the fluidity is low. .

  FIG. 7 shows an example in which when the sample is packed in the flow cone of the slump test and the flow cone is pulled out to the upper part, the state where the raw corn flows out and spreads from the bottom is measured as the flow value.

In this case, the lower limit of the test value is 20 cm in diameter at the bottom of the flow cone. That is, the slump flow value of 20 cm is not flowing. In this example, it can be determined that the sample (1) is 1 kg / m ³ and the sample (2) is 2.5 kg / m ³ and has no fluidity. The same raw concrete as the sample shown in FIG. 20 is used.

  In this way, it is possible to suppress the flow state of surplus raw kon with the aggregating agent. In addition, the state in which the slump value in the slump test in FIG. 20 is zero (0) is a state in which the shape is maintained even when the slump cone is pulled out, and can be transported by a belt conveyor, and can be easily loaded. Can be done.

  In general, raw kon used a surfactant such as an AE water reducing agent so as to maintain fluidity, and even if the amount of water is small, it is easy to knead and separates independent bubbles to improve the operability of the raw kon. It is made to form like this. Further, during kneading with a mixer at the time of production of the ready-mixed product, the design is made in consideration of the blade shape of the mixer, the number of revolutions, the kneading time, the kneaded amount, etc. that suppress the entrainment of the continuous air amount in the ready-mixed product.

  Thus, the raw kon is mixed with the AE water reducing agent and is in a dispersed state. The high molecular weight exhibiting the surface activity is, for example, about several tens of thousands if the molecular weight is polycarboxylic acid, and the molecular weight in the high molecular weight agent is never high. In order to bring this dispersed state into an agglomerated state, an anionic polyacrylamide (A-PAM) polymer agent having a high molecular weight close to 10,000 times the molecular weight is used to cause an aggregating action. However, if the flocculant is not formed by stirring the surplus kon, the aggregated state is not obtained. The stirring device 4 is an essential condition for bringing the agglomerated state.

  In addition, the amount of addition varies depending on the state of surplus corn. The condition here is that raw concrete is composed of aggregate, cement, water, and admixture. Of these, sand, gravel, crushed stone, etc. in aggregates with a particle size of approximately 1 mm or more are solid. What is considered to be agglomerated is a cement slurry in which cement, water and an admixture are mixed.

  This cement slurry contains cement particles and fine particles, and when the aggregating agent is added, strong agglomeration occurs instantaneously and fluidity is lost. As a result, the cement slurry enters the gaps between the aggregates in a state where the adhesive strength is increased, so that the air gaps are also increased and become aggregated.

  However, when there is a lot of moisture, the adhesive strength is weak, so the amount of gap generated by the agglomeration becomes small. In other words, the contact area between the fine aggregate and the coarse aggregate existing in the cement slurry is reduced to be aggregated, air gaps are generated, and there is an effect of increased adhesive force, which is less than that between aggregates. Adsorbed at the contact area.

  The mechanism by which the aggregating agent and surplus kon used in the present invention are aggregated will be described with reference to FIG. 8, but the mechanism of the aggregation according to the present invention is different from the aggregation of water treatment.

  In the field of water treatment, the particle size of the suspension in the waste water of polymer flocculant (used in a different meaning from wastewater) is generally said to be less than 100μm (0.1mm) ( Japanese Science Information, “Latest Technical Trends and Industrial Applications of Water-soluble, Water-dispersible Polymer Materials” 2001). The use of a flocculant in the case of water treatment is mainly to agglomerate suspended matters in water to increase the precipitation rate.

  The present invention is not improvement of sedimentation / sedimentation as in water treatment, but is agglomeration of surplus kon which has an extremely small amount of water. The moisture content of surplus raw kon is about 15% at most in terms of mass ratio (water content), and the proportion of raw kon at the time of shipment is about 10% or less, and it is assumed that it is about 10-12% even in the future. Many. Therefore, the water content is overwhelmingly smaller than in the case of suspended water for water treatment, and the proportion of fine particles is also smaller than the overall particle size distribution. That is, it is different from the applicable range of the polymer flocculant that is said to be used in water treatment.

  The fine aggregates of ready-mixed concrete are targeted for particle sizes of coarse particles less than 10mm in the soil classification. Cement slurry and fine particles are attached around the sand particles.

  The soil classification based on the Japan unified soil classification method shown in Fig. 11 shows the particle sizes of fine and coarse aggregates used in ready-mixed concrete. The applicable range of the particle diameter of the suspension of the polymer flocculant in the water treatment corresponds to the fine particles contained in the fine aggregate referred to as raw concrete. The cement particles are fine powder of 10 μm or less, but are made into a paste by agglomeration due to cement hydration.

  The mixture of ready-mixed food is designed from the mass ratio W / C of water and cement. However, surplus cooked corn is considered to be unnecessary corn on the construction site, and is hydrated as waste kon, and may be in a state of more moisture than designed. Due to the addition of water, the density is lower than that of the original raw concrete.

  That is, since the volume of surplus raw concrete is larger than the original raw concrete, the ratio of the amount of fine particles and cement in the unit volume of surplus raw concrete is smaller than the blending ratio at the time of shipment. Therefore, since the water content increases, the fluidity also increases, so the state of agglomeration worsens as the water content increases. However, since the fluidization is maintained at a level where the total moisture content is increased by about 2 to 3% at most, the water content of raw corn is different from the moisture content and water content of water treatment.

  In the case of the agglomeration of the present invention, the adhesive force generated by the expansion of flocs due to the aggregation of fine particles or less including cement particles in surplus kon increases rather than precipitation / sedimentation as in water treatment. Adheres to the sand, and aggregates formed on the sand also form aggregates.

  This increase in adhesion is thought to be due to the increased cohesive force because excessive moisture is not taken in due to strong agglomeration with the hydrated cement particles in the cement slurry.

  The reason why the adhesive strength increases due to moisture is only the fine particles with relatively excellent water absorption ability and the cement with excellent water absorption ability and good hydration property, which are contained in fine aggregates which have poor water absorption ability in raw concrete raw materials. Therefore, the cohesive action is strong and the adhesive force is increased. At this time, the free water in the surplus kon is also drained and remains in the gap. This moisture is later vaporized.

  As shown in FIG. 8, the agglomeration of surplus kon increases the agglomeration effect by the aggregating agent and the cement concentration, and increases the adhesive force with the passage of time and the synergistic effect of the adhesive force of the fine molecules. Minute particles adhere to fine particles, and the chain of adhesion affects the coarse particles.

  In the initial agglomeration in the action of agglomeration, a certain amount of particles below the fines is necessary. In order to reduce the unit water amount of surplus kon with a high amount of water, and those with a particle size distribution from fine particles to coarse particles, such as reclaimed sand, which adhere to the aggregates, they tend to adhere to the coarse aggregate. A gap amount can be secured.

  Aggregation by adding aggregate agent to mortar (sand + cement + water), considering aggregates (crushed stone and gravel) in concrete as solids, assuming no effect on volume change during aggregation. FIG. 9 shows the change in the cement water ratio W / C based on the amount of air gap and vaporized water in the initial stage of the mortar until the age of 4 days. In the figure, P is the value of mortar, and G is the value of aggregated mortar.

  According to this, W / C is smaller in the agglomerated mortar, the amount of water per unit volume hydrated is reduced, and the moisture concentration of the cement hydrate itself is increased. . In general, the higher the cement paste concentration, the greater the strength. However, in this case, the unit cement amount is reduced by agglomeration, and the entrained air amount is increased, so that it becomes a solidified product in a porous state and the strength is reduced.

  Aggregation of surplus kon increases the agglomeration effect by the aggregating agent and the cement concentration, and the finer particles become finer particles due to the synergistic effect of the increase in adhesion and the adhesion of fine molecules over time. Adhesion and the chain of adhesion affect the coarse particles.

  Among these, excess water other than the water confined by cement hydration or agglomeration due to the action of agglomeration adheres to the surface of the agglomerated material or stays in the gap, and the rest is vaporized. Since the interstitial water and adhering water are also vaporized over time, the water in the interstices in the aggregate is replaced with air, and the air gap amount increases.

  Since the coarse aggregate in the ready-mixed corn has a large particle size and is a solid, FIG. 10 shows the situation when the aggregated state is examined using mortar.

  The photograph on the left side of FIG. 10 shows the situation when the aggregate aggregated using mortar is examined because the coarse aggregate in the ready-mixed corn has a large particle size and is a solid matter. The photograph on the right is a photograph of the volume change when the same amount of mortar is agglomerated.

  Even when visually compared with the mortar on the right side when aggregated in the photograph on the left side, it can be clearly seen that the voids are increased compared to the normal mortar. Since the volume increased about 1.4 times as shown in the right photograph, it can be judged that the gap increased by about 40%. In the case of surplus raw concrete, coarse aggregate as solid matter is contained in this, so if this volume is converted as a fixed value, the gap will be about 15 to 17% even if estimated to be small. However, this is a numerical value assuming a state in which the surplus kon and the aggregating agent are well stirred and the gap is not broken.

Next, a description will be given of fine particles or regenerated sand as an auxiliary material added by the auxiliary material addition feeder 5. These fine particles and reclaimed sand improve the binder ability (adhesion performance) of the aggregating agent, and the fine particles with a particle size of 0.15 mm or less are unit per 1 m ³ of surplus corn volume. Add 0.5kg / m ³ or more of the added amount, or in the case of reclaimed sand, add regenerated sand with particles of 1mm or less in particle size distribution of 40% or more and unit addition amount of 15kg / m ³ or more per 1m ³ of surplus kon volume.

  In order to maintain fluidity, the blended water of ready-mixed food is blended in an amount greater than the amount of water theoretically required for cement hydration. However, in addition to the water required for hydration, there is some water that is not drained.

  In the ground improvement, etc., there is an example in which quick lime is used for the muddy soil, but in the present invention, dehydration and solidification are considered in consideration of collecting and regenerating aggregate from surplus raw concrete. In order to give surplus kon an environment in which the flocculating agent easily aggregates with particles of fine particles or less and the flocs due to the chain are easy to expand without using quick lime etc. In order to improve the binder ability (adsorptivity) of the agent, the fine particles and fine particles are added to promote aggregation.

  The fine particles and fine particles to be added may be slag as well as the silt / clay shown in FIG. 11, but are obtained from raw raw material in consideration of the work process of collecting aggregate from surplus raw raw material. By using the reclaimed sand, it can be easily prepared in the ready-mixed concrete factory, and it is not a new purchase, so there is a great economic merit, and no new waste is generated in the aggregate regeneration process.

As an example, FIG. 12 shows the change in the flow value of slump cones of aggregated products according to the added amount of regenerated sand with the addition amount of the aggregating agent fixed. According to this, it can be seen that by adding 15 kg / m ³ or more of surplus kon per unit volume, the lower limit is 20 cm, that is, 0 (zero) when converted to a slump value.

  FIG. 13 shows the particle size and the passing mass percentage (particle size distribution) of the recycled sand used. In the example shown in FIG. 12, the factory B recycled sand of FIG. 13 is used.

When the applicable range of the particle diameter of the suspension in the waste water of the polymer flocculant described above in the water treatment field is 0.1 mm, the passing mass percentage is in the range of 5 to 9% in the case of reclaimed sand. From these, it can be seen that the amount of addition of particles of 0.1 mm or less was converted to about 1 kg / m ^{3 when} the addition amount of 15 kg / m ³ was converted to the surplus kon volume.

  In general, in the screening test for quality control of fine aggregate of raw concrete, the minimum diameter of the sieve is 0.15mm, and it can be grasped only by the distribution amount of 0.15mm in daily management. Usually, since the distribution amount of the particle size smaller than this is not examined, on the basis of the distribution amount of this particle size of 0.15 mm, in the example of the reclaimed sand, particles of 0.15 mm or less are contained by 10% or more. When using reclaimed sand, the particle size distribution of 0.15 mm may be used as a guide. Further, since fine aggregate is 0.075 mm or less in fine aggregate, this may be used as a guide.

In the present invention, not only the effect of the aggregating agent but also the stirring method is devised to increase the gap amount. The stirring device 4 is as described above, but the stirring device shown in Table 1 below. The example which measured the air gap | interval amount of the surplus kon using this will be described. The following knowledge was obtained from the test shown in this example.

  The aggregated state varies depending on the state of surplus kon, but in the case of using surplus kon with a moisture content of about 10%, the air gap amount in the aggregated state is used as a guide and converted from the wet density of the aggregate. If it asks for it, compared with a batch type, the amount of air gaps can be enlarged in a continuous mixer. The functionality was as follows.

Raw corn agitator: unsuitable for agglomeration and deposits of 100 kg / m ³ remain in the drum.
Forced twin-shaft mixer: Although it was judged by the stirring time because rotation control is difficult, there is a high possibility that re-kneading fluidization will occur. Reflow can be suppressed by setting the surplus raw-condensation amount to 70% or less of the mixer specifications, but it is inferior in processing capacity because it becomes a batch operation. (1 batch: 2m ³ )
Two-shaft continuous mixer: There are two stirring shafts to create a dead zone between the shafts. Since the cleaning operation takes time, it is necessary to pay attention to the casing structure. (Processing capacity: 15m ³ / hr)
Uniaxial continuous mixer A type: By controlling the number of rotations of the existing mixer for remixing raw concrete, the aggregated state is improved. However, depending on the casing structure, it takes time to clean the work after completion. (Processing capacity: 30m ³ / hr)
Single-shaft type continuous mixer B type: Manufactured in consideration of agglomeration, the casing has a liner-tex structure with high purity of natural rubber, and has more paddle parts than the specifications in (4). (Processing capacity: 35m ³ / hr)

  As a result, the continuous mixer has little reworking, and since it takes a few seconds from the supply of surplus raw material to the discharge, the result is that workability is high.

  The air gap amount of the specimen solidified in the aggregated state is much larger than that in the surplus raw concrete. FIG. 14 shows the results of measuring the compressive strength and fracture energy of the specimens solidified after being aggregated.

  In addition, the same mixture was used for the surplus kon used in the test. According to this, it turns out that the compressive strength of the specimen solidified after the aggregation is about 1/3 to 1/4 compared with the surplus kon after curing. On the other hand, as for the breaking energy, it can be seen that the agglomerated and solidified material is 1/10 or less compared to the raw raw concrete after hardening. Although the fracture energy value is a converted value, since the aggregated solidified product has a more porous structure, the density is smaller than that of the cured surplus kon. Although the state of specific destruction differs depending on the age of the material, in the case of 4 days after the age of the material, it was destroyed at a height of about 12 m after the surplus raw concrete after curing.

  On the other hand, what solidified after agglomeration was broken at a height of 0.5 m. The compression test is a method in which the pressurized surface is pressed against the specimen, and compared to this, the dropped test is dynamic. Is good. That is, in the operation of classifying surplus raw kon and collecting aggregates, it can be determined that a light crushing process is better if solidified after agglomeration.

  An example of the destruction state is shown in FIG. In the broken state, the agglomerated one is a cross-section in the case of surplus raw concrete that has been hardened and crushed well. There is a high possibility that the temporary crushing work of the aggregate collection method can be omitted.

  A histogram of the air gap amount of the specimen used in this test is shown in FIG. The specimen used for this test used what was implemented with the uniaxial continuous mixer A type shown in Table 1, and the air gap amount of the formed specimen was about 11% on the average. As shown in Table 1, the B type has a larger air gap amount than the A type.

  Also, when the amount of gap including moisture content is converted from wet density, etc., it is difficult to handle the specimen when it is carried out with a mechanical device, and it is 21% on average when it is solved, and average when packed in the specimen. 14%. This is shown in FIG.

  From these examples (test results), the solidified state after agglomeration remarkably reduces the amount of energy at the time of destruction compared to the cured surplus kon. Even considering the increase in volume due to the increase in the gap, the amount of work in the process of manufacturing recycled aggregate is reduced and the crushing work is facilitated.

  In addition, the work / equipment associated with the reuse of surplus raw concrete can be reduced, for example, it can be reused as roadbed material and backfill material without classification.

  The regenerated aggregate obtained in this manner is equivalent to the quality that is obtained by crushing the hardened concrete, and it is possible not only to use recycled products in the ready-mix factory but also to commercialize them. (See Table 2)

  Next, the manufacturing method of the recycled material by aggregation of surplus kon is described as subsequent processing when surplus kon is aggregated in the present invention.

  As shown in FIG. 18, it is divided into the case of solidifying and implementing the aggregate formation in the classification of surplus kon related to the present invention, and the flow executed immediately (immediately) as shown in FIG.

  In the case of FIG. 18, the solidified state is measured by the hydration action of cement and moisture in the ready-mixed concrete, and the solidified state is crushed.

  In the former, surplus raw kon is agglomerated, crushed after a few days, and the coarse particles are divided into fine particles by gravity decoration, and the fine particles attached to the coarse particles are removed with a vibrating sieve and coarsened. Classify aggregate (gravel). It should be noted that the crushing equipment can be efficiently put into a predetermined size with an excavator or the like.

  In the latter, after surplus kon is agglomerated, coarse particles are divided into fine particles by gravity decoration, and fine aggregates attached to the coarse particles are eliminated by vibration decoration to remove coarse aggregate (gravel). Classify. In addition, since vibration decoration is used in order to improve the quality of coarse aggregate, when performing only classification, only a gravity type may be used.

  When surplus kon shown in FIG. 18 is agglomerated and classified after solidification, a slight crushing operation is required. On the other hand, in the case of immediate classification shown in FIG. 19, there is no crushing work, and the aggregated product is directly fed into the classifier, so that the aggregated product that has not yet solidified on the screen (net) of the classifier. Since there is a high possibility that the part will adhere, a rotary sieve is preferable to sieving at high speed vibration such as a vibrating sieve.

  It is no longer a device with a mechanism that enables classification by managing the state of the aggregates on the premise of immediate classification. In other words, it is possible to classify immediately by determining the amount of an appropriate aggregating agent and auxiliary material such as reclaimed sand added from the state of surplus raw concrete and monitoring the screen of the sieve device. In the case of classification after aggregation, it is easier to manage than immediate because the solidification action is cement hydration only by securing a certain amount of air voids (10% or more).

  In addition, the generated aggregated surplus kon is solidified by the hydration action of cement and moisture in the raw kon, and the solidified material is crushed and used as part of the backfill material. It can also be a roadbed material (RC material).

Table 2 below shows the test results of the recycled aggregate obtained by classifying surplus kon after aggregation.

  From the quality evaluation test examples shown in Table 2, it was proved that evaluation as a recycled aggregate can be obtained although the quality varies depending on the classification method. The immediate classification case 1 and the case 2 are based on the model of the sorting device. H, M, and L in each quality evaluation are evaluations determined by JIS, and the test results in Table 2 are those that have been implemented and evaluated by specialized institutions.

It is a flowchart which shows the aggregation method of the surplus kon of this invention. It is explanatory drawing of the stirring apparatus used with the agglomeration method of the surplus kon of this invention. It is explanatory drawing which shows each example of the stirring apparatus used with the agglomeration method of the surplus kon of this invention. It is a top view which shows the example of installation of the stirring apparatus used with the agglomeration method of surplus kon of this invention. It is a side view which shows the example of installation of the stirring apparatus used with the method of aggregating the surplus kon of this invention. It is a front view which shows the example of installation of the stirring apparatus used with the method for aggregating the surplus kon of the present invention. It is a graph which shows the result of having measured as a flow value the state which the raw concrete flows out from the bottom and spreads, when the flow cone is pulled out to the upper part in the state which packed the sample in the flow cone of the slump test. It is the conceptual diagram explaining the mechanism in which an aggregating agent and surplus kon are aggregated. Aggregation by adding aggregate agent to mortar (sand + cement + water), considering aggregates (crushed stone and gravel) in concrete as solids, assuming no effect on volume change during aggregation. It is a graph which shows the change of the cement water ratio W / C from the air gap | interval amount and the water | moisture content which vaporized in the initial stage by the age of the mortar 4th. Since the coarse aggregate in the ready-mixed corn has a large particle size and is a solid matter, the volume change when the same amount of mortar was aggregated as the state of aggregation using mortar was investigated. It is a state figure by the photograph at the time. It is explanatory drawing which showed the particle size of the fine aggregate and coarse aggregate used for raw concrete for the soil classification by the Japan unified soil classification method. It is the graph which showed the change of the flow value by the slump cone of the aggregated material by fixing the addition amount of an aggregating agent, and the addition amount of regenerated sand. It is the graph which showed the particle size and passage mass percentage (particle size distribution) of the used reproduction | regeneration sand. It is a graph of the result of having measured the compressive strength and the fracture energy of the specimen solidified after aggregated. It is a state figure by the photograph which shows the example of a destruction state. It is a histogram figure of the air gap | interval amount of the test body used for the test. It is a graph of the result of having converted the gap | interval amount including even the moisture content from the wet density etc. FIG. It is explanatory drawing of the method of aggregating surplus kon and classifying after solidification. It is explanatory drawing of the method of classifying a surplus raw kon immediately after agglomeration. It is a graph which shows the addition amount of an aggregating agent, and the change of a slump value in the slump test for evaluating the workability-ability of raw concrete. It is an internal conceptual diagram of an agitator mounted on a raw concrete vehicle. It is explanatory drawing which shows the fluidization state of the agitator mounted in a raw concrete vehicle.

DESCRIPTION OF SYMBOLS 1,3 ... Screw 2 ... Paddle 4 ... Stirring device 5 ... Quantification feeder 6 ... Raw concrete car 7 ... Auxiliary material addition feeder 8 ... Control panel 9 ... Aggregating agent addition device

Claims (9)

The fresh concrete Retained surplus you are fluidized in agitator mounted fresh concrete vehicles 1-shaft or two-shaft from A Jiteta after discharge, the rotational speed of the stirring device is subjected to a continuous stirrer to 100 min ^-1 or more in advance Emulsified polymer aggregating agent based on an anionic polyacrylamide (A-PAM) having a weight average molecular weight of 10 to 25 million and 25 to 100 mol% as an anionic monomer Is added, and the amount of air gaps is increased by the stirring device. Anionic polyacrylamide (A-PAM) polymer group grain agent composed mainly of has a range of units amount to be added to the volume 1 m ³ per excess raw Con 0.5kg / m ³ ~5kg / m ³ The method for assembling surplus raw kon as claimed in claim 1. Fine fraction below has been crushed minerals, industrial bentonite, slag, clay minerals or we selected particle size 0.15mm The following fine fraction below a particle fraction of surplus raw Con volume 1 m ³ per unit amount 0.5kg The method for agglomerating surplus kon as claimed in claim 1 or 2, wherein / m ³ or more is added. 4. The surplus surplus kon group according to any one of claims 1 to 3, wherein a unit addition amount of 15 kg / m ³ or more per 1 m ³ of surplus con is added to regenerated sand having a particle size distribution of 40% or more in a particle size distribution of 1 mm or less. Granulation method.   The method for agglomerating surplus corn according to any one of claims 1 to 4, wherein the agitation device for increasing the air gap amount of the surplus corn is a continuous agitation device having paddle type blades. The aggregated surplus kon produced according to claim 1 is divided into a coarse part and a fine part by a classifier of a classifier selected from a trommel or a vibrating sieve immediately after the aggregate is formed into an aggregate. A method for producing recycled material by agglomeration of surplus kon which is a feature. The aggregated surplus kon produced according to claim 1 is solidified by the hydration action of the cement and water in the surplus kon, and the solidified state is crushed, and the coarse particle fraction is obtained by a classifier that is a vibrating sieve. A method for producing recycled material by agglomeration of surplus kon, characterized in that it is divided into fine particles and used as a part of aggregate or backfill material or roadbed material . Excess raw concrete that is fluidized in an agitator mounted on a raw concrete vehicle is discharged into a stirrer and pre-emulsified. be of the anionic polyacrylamide high molecular group grain agent was added, agglomerates apparatus for use in Dan granulation processing method excess raw con which is characterized by increasing the air gap volume by the stirrer Characterized in that it is equipped with a quantification feeder for quantifying the amount of surplus kon supplied to the stirrer and a polymer aggregating agent addition device for adding the polymer aggregating agent to the surplus kon Aggregation device used for the agglomeration method of surplus kon. Furthermore, the aggregate formation apparatus used for the aggregate formation method of the surplus raw concrete of Claim 8 equipped with an auxiliary material addition feeder.