JPH0818324B2 - How to treat residual unfinished concrete - Google Patents

Description

Detailed Description of the Invention

[0001]

[Field of Industrial Application] The present invention relates to a treatment method for separating and recovering residual raw concrete in a raw concrete plant or a raw concrete mixer truck into aggregates and the like.

[0002]

2. Description of the Related Art Conventionally, as a method of treating this residual raw concrete, the residual raw concrete is temporarily stored in a mud collecting tank, and all of the residual raw concrete in this mud collecting tank is directly aggregated by using a sand pump. It was supplied to a separation device to separate coarse aggregate, and then sent to a classifier to separate fine aggregate. In this method, a large amount of water is required to completely convey the residual green concrete from the mud collecting tank by the sand pump, and a high performance pump is required. As a result, a huge amount of energy is required. Moreover, since the residual raw concrete is stored in the mud collecting tank at one time, it has a drawback that it is easily solidified. In order to improve it, Japanese Patent Publication No. 62-27965 discloses that the primary recovery is to discharge the residual raw concrete only to the hopper of the coarse aggregate separating device by dropping energy and to guide it to the coarse aggregate collecting device to separate the coarse aggregate. The residual content is transferred to any desired position via pump means and the secondary aggregate is separated to perform separation of fine aggregate, thereby separating coarse aggregate and fine aggregate from residual raw concrete. A method of collecting is disclosed.

[0003]

In this conventional method, in the primary recovery, the residual raw concrete is dropped directly into the hopper and sent to the coarse aggregate separating and recovering device, so the mesh of the separating and recovering device is clogged and the gravel is drained. The gravel is not sufficiently separated from the mixed water of the sand and the sludge water, and the gravel containing a large amount of the sludge water mixed with the sand is discharged to the belt conveyor for conveying the gravel. Therefore, the collected gravel contains a large amount of sand and sludge and is not suitable for reuse. Further, since the wet gravel is conveyed, sand and sludge cause great wear of the rollers of the belt conveyor. In addition, the amount of sewage increases to clean the clogging of the coarse aggregate separating device. In secondary recovery for separating sand and sludge water, since fine sand is often mixed in sludge water, it is necessary to install a cyclone or the like to separate it from sludge water. The present invention provides a method for eliminating such drawbacks.

[0004]

[Means for Solving the Problems]

The present invention uses residual raw concrete as coarse aggregate,
In the method of separating and collecting fine aggregate, sludge and filtered water, the residual raw concrete is discharged to the car wash chute, at the same time, the sludge water is sent to the car wash chute, and the residual raw concrete is diluted while being washed away by the sludge water. A first step of washing the aggregate and sending it from the chute to the coarse aggregate recovery device to separate the residual raw concrete into coarse aggregate and diluted residual raw concrete (mixed water of fine aggregate and sludge water);
The separated diluted residual raw concrete is sent to a flow rate adjustment tank, and from there it is sent to a sand separator while adjusting the flow rate to separate the diluted residual raw concrete into fine aggregate and sludge water, and the separated sludge water A second step of sending a part of the above to the first step, and a third step of separating the remaining sludge water separated in the second step and not sent to the first step into sludge and filtered water by a dehydrator. It is characterized by.

[0006]

[Action]

The first step is a coarse aggregate separating step. In that process, residual raw concrete is diluted and mixed by sludge water while being washed away in the car wash chute, so coarse aggregate and fine aggregate are well washed with low concentration sludge water, and coarse aggregate, fine aggregate and Separated into diluted sludge water. In that state, the coarse aggregate is separated by the separating device, so that the coarse aggregate separating device can separate clean coarse aggregate with high purity.

The second step is a fine aggregate separating step. The diluted residual ready-mixed concrete separated in the previous step is sent to the flow rate adjusting tank and sent to the sand separator while being adjusted to a constant flow rate. By this adjustment, the flow in the sand separator becomes constant and stable sand sedimentation occurs. At this time, the fine sand also settles with the sand. Since the sand is separated in this state, clean, high-purity sand is recovered. The amount of fine sand in the sludge water separated from the sand is small.

The third step is a step of sending the sludge water separated in the second step to a dehydrator to separate it into sludge and filtered water. The filtered water separated here is water with a very low sludge content. As described above, the present invention collects and reuses the aggregate from the residual fresh concrete, without using the sludge water as the process water and the filtered water as the water for mixing the concrete without discarding the residual raw concrete. Can be reused.

[0010]

EXAMPLE FIG. 1 is a plan view of a plant for separating and collecting clean gravel (coarse aggregate), sand (fine aggregate), sludge, and filtered water from residual raw concrete, which is an embodiment of the present invention. Indicates. In the figure, the alternate long and short dash line indicates the pipeline.

This plant is operated by a general operation panel 1. The car wash chute 3 is installed on the ground surface, has a U-shaped trough shape with a slight downward slope toward the octatron mel 11 (coarse aggregate separating device), and three green concrete cars can work simultaneously. The octatron mel 11 is horizontally installed on a water collecting pit 17 formed below it. The octatron mel 11 is an octagonal tubular body, and a net is stretched on eight side surfaces. Further, a mixer plate is provided on the inner side of the eight side surfaces to perform mixing and feeding of solid matter. Diluted residual fresh concrete is sent into it from the car wash chute 3 side, gravel is discharged from the other side, diluted residual raw concrete (mixed water of sand and sludge water) flows out from the mesh, and water is collected at the bottom. It is structured to be sent to the pit 17. The water collecting pit 17 has a recovery pump 19. The recovery pump 19 is suspended so as to be movable in the pit. Belt conveyor 13 is Octatron Mel 11
The gravel discharged from the gravel is conveyed to the yard space 15.

The screw conveyor 21 (sand separator) has a flow rate adjusting tank 23 at its upper part. The screw conveyor 21 has an ascending inclination of 20 degrees as shown in FIG. 2 described later, and its case forms a storage tank for diluted residual ready-mixed concrete. Sand of diluted residual ready-mixed concrete is deposited in the tank, pushed up by the rotary screw at the bottom, discharged from the top end and dropped into the yard space 27. The separated sludge water overflows and is sent to the raw water tank 5. The flow adjustment tank 23 is located in the water collection pit 17.
The diluted residual ready-mixed concrete from is sent to the screw conveyor 21 while adjusting the flow rate, and the surplus is returned to the car wash chute 3. The raw water tank 5 is a perforated sludge water storage tank having an agitator 30 and a pit 32 at one end. It also has a water pump 7 and a transfer pump 31. Both pumps 7 and 31 are movably suspended on the bottom of the raw water tank 5. The water pump 7 sends the sludge water to the car wash chute 3. The transfer pump 31 sends the sludge water to the intermediate receiving tank 35 provided at the upper end of the raw water tank 5 and sends it to the dehydrator 41 by the pressure sending pump 37.

The dehydrator 41 is installed on the yard space 43. The sludge water is separated into sludge and filtered water by the dehydrator 41, and the sludge falls and is stored in the yard space 43 installed therebelow. The filtered water is sent to the perforated supernatant water tank 47.

The supernatant water tank 47 has a BP pump 49 (batcher plant pump) and a pressurizing pump 55. Both pumps are movably suspended at the bottom of the supernatant water tank 47. The BP pump 49 sends the filtered water to the batcher plant, and the pressurizing pump 55 sends the filtered water to the pressurizing tank 59 installed on the ground surface. This pressurized tank 5
9 is maintained at ^{3.8kg / cm 2 ~2.6kg / cm 2} . This filtered water is sent from the pressure tank 59 to the car wash chute 3, the octatron mel 11, the ready-mixed concrete mixer car, etc. as needed for cleaning.

The present invention will now be described by way of an example of operation of the above apparatus. FIG. 2 is a schematic flow sheet thereof. This plant consists of three steps, and all steps are operated by the general control panel 1. The first step is a step of separating gravel and diluted residual raw concrete from the residual raw concrete.

First, the residual fresh concrete is discharged from the ready-mixed concrete mixer car to the car wash chute 3, and at the same time, sludge water is sent from the raw water tank 5 to the car wash chute 3 through the pipe 9 by the water pump 7. The residual raw concrete discharged by the sludge water is diluted while being washed away, and the mixed gravel, sand, and (aggregate) are washed and separated and supplied to the octatron mel 11. Therefore, since the gravel, the sand, and the sludge water are separated from each other in the diluted residual fresh concrete and are supplied to the octatron mel 11, the gravel is completely separated in the octatron mel 11. Then, the cleanly separated gravel is discharged onto the belt conveyor 13, and the belt conveyor 13 causes the yard space 15
Sent to and stored. The gravel is completely separated and drained sufficiently to dry it, and the belt conveyor 13
Since the roller of the belt conveyor 13 is supplied to the roller, the roller of the belt conveyor 13 is hardly worn by sand, sludge, etc., and the life is extended. The diluted residual fresh concrete that has been filtered and separated from the mesh of the octatrommel 11 gathers in the water collecting pit 17 provided under the trommel 11.

Unlike the conventional machine in which the structure is a cylindrical body, this octatron mel 11 forms an octagonal cylindrical body, and separates the residual fresh concrete in the state of being diluted and separated, so that it does not become clogged. Separation of gravel is completed and clean gravel is obtained. Also, sludge water can be circulated and used as this dilution water, and since the octatron mel 11 does not become clogged, there is no need for cleaning and no makeup water from outside the system is required, thus reducing the generation of waste water. It In the process of this plant, the capacity of the residual fresh concrete is quantified by the capacity of the water pump 7.

The second step is a step of separating the diluted residual fresh concrete into sand and sludge water. The diluted residual raw concrete in the water collecting pit 17 separated in the previous step is sent by the recovery pump 19 to the flow rate adjusting tank 23 provided on the screw conveyor 21 via the pipe 25. The diluted residual ready-mixed concrete is supplied from the flow rate adjusting tank 23 to the screw conveyor 21 inclined upward to separate the sand by adjusting the flow rate to a constant value with a valve installed below the flow rate adjusting tank 23. The case of the screw conveyor 21 forms a storage tank, which has a large overflow surface area and a small flow velocity in the tank to improve sedimentation of fine sand and prevent overflow of fine sand. The diluted residual fresh concrete supplied at a constant flow rate is agitated and separated by the volume and shape of the screw body and the low-concentration sludge water. Therefore, the sand is sufficiently washed so that the sludge does not adhere to it, and clean sand is separated. This sand is collected from the head of the screw conveyor 21 and stored in the yard space 27. Further, for adjusting the flow rate in the flow rate adjusting tank 23, the surplus portion of the diluted residual ready-mixed concrete is again piped to the car wash chute 3.
The water is returned via 8 and serves as a replenishing water for the dilution water, and also prevents the recovery pump 19 from clogging with sand. Further, the sludge water that has been cleared by the screw conveyor 21 to prevent the fine sand from flowing out overflows and is sent to the raw water tank 5 through the pipe 29. The sludge water is sufficiently separated from the sand and does not require a step of removing it with a cyclone or the like. Therefore, the sludge water is directly sent to the car wash chute 3 by the water pump 7 as described above.

The third step is a step of treating excess sludge water. Excess sludge water in the raw water tank 5 is sent to the intermediate receiving tank 35 by the transfer pump 31 via the pipe 33, and from there, the dehydrator 41 is sent by the pressure pump 37 via the pipe 39.
Sent to. In the dehydrator 41, the sludge is separated into sludge and filtered water, and the sludge is stored in a yard space 43 installed below the dehydrator 41. The filtered water is sent to a supernatant water tank 47 via a pipe 45 installed below the dehydrator 41. The filtered water is sent by a BP pump 49 via a pipe 51 to a batcher plant (not shown) and is reused as raw mixed water. Excess water in this batcher plant is returned to the supernatant water tank 47 via the pipe 53.
Further, the filtered water is sent to the pressure tank 59 via the pipe 57 by the pressure pump 55. The pressure tank 59 functions as a buffer tank, and the stored filtered water is sent to the car wash chute 3, the octatron mel 11, the raw concrete mixer car (shown in FIG. 1), etc. through the pipe 61 as necessary, Used for cleaning plants. External purified water is introduced into the pipe 61 through the pipe 63 as needed.

In this plant, sludge water is sent to the car wash chute 3 in the first step, and the residual raw concrete is diluted and washed to separate it into clean gravel and diluted residual raw concrete (mixed water of sand and sludge water). By supplying a fixed amount of the diluted residual fresh concrete from the flow rate adjusting tank 23 in the two steps, the sand is separated well and the sand and the sludge water with high purity are separated. In this way, gravel can be collected in the first step and sand can be collected in the second step in a highly pure and clean state. Also, the sludge water separated in the second step does not contain sand, so a cyclone step is not required. In the third step, sludge water is separated into sludge and filtered water, and the filtered water is reused for mixing fresh concrete. As described above, this plant treats the residual raw concrete and reuses the aggregate and the filtered water, thereby making the industrial waste only sludge and contributing to pollution prevention and resource saving.

[0021]

In the first step of the present invention, the car wash chute is
Due to the provision, the car wash chute remains
Diluted and mixed with sludge water while swept away.
Coarse aggregate and fine aggregate into low concentration sludge water
Well cleaned and coarse aggregate, fine aggregate and diluted sludge
It becomes separated into water. Flow to the separation device in that state
The coarse aggregate separation device will not be clogged.
The coarse aggregate is completely separated and the clean coarse aggregate is rotated.
There is a great effect that can be stored. Also the coarse aggregate
The belt conveyor that conveys
Since this conveys clean aggregate, this conveyor roller
No noticeable wear and long lasting. Separated and collected here
The coarse aggregate can be reused in the same way as the new coarse aggregate.
come. In the second step, the dilution residue supplied to the sand separator
The flow is stabilized by adjusting the flow rate of raw concrete
The fine aggregate and the fine aggregate settle in the sand separator case.
Separated to obtain high-purity fine aggregate (sand)
It On the other hand, the sludge water separated here is fine aggregate (fine
(Sand) is collected without mixing, so it can be cycled during the process.
Does not require Ron Separator. In the third step,
Separating di-water into sludge and filtered water with a dehydrator
Therefore, if sludge hardly accumulates in the treatment process,
This has the effect. Therefore, troubles due to sludge accumulation
The process management becomes easier. The filtered water is sludge
Water with a low content of
It is suitable for reuse as water. As described above, the present invention remains
It greatly improves the treatment method of living concrete.
It It also greatly contributes to pollution prevention and resource saving.
It

[Brief description of drawings]

FIG. 1 is a plan view of a treatment plant for residual fresh concrete.

FIG. 2 is a schematic flow sheet diagram of residual ready-mixed concrete.

[Explanation of symbols]

Car wash chute 11 Octatrommel
21 .. Screw conveyor 23 .. Flow rate adjusting tank 41 .. Dehydrator

Claims (1)

[Claims] 1. A treatment method for separating and recovering residual raw concrete into coarse aggregate, fine aggregate, sludge and filtered water, the residual raw concrete is discharged to a car wash chute, and at the same time, sludge water is sent to the car wash chute, The first step of diluting the residual raw concrete while washing away with the sludge water to wash the aggregate, and sending it from the chute to the coarse aggregate recovery device to separate the residual raw concrete into the coarse aggregate and the diluted residual raw concrete, The separated diluted residual raw concrete is sent to a flow rate adjustment tank, and from there it is sent to a sand separator while adjusting the flow rate to separate the diluted residual raw concrete into fine aggregate and sludge water, and the separated sludge water Part of the sludge is sent to the first step, and the remaining sludge water that is separated in the second step and cannot be sent to the first step is sludge and filtered water in a dehydrator. Third step and the processing method of the residual raw concrete, characterized in that by separating the.