JPH1024201A - Solid-liquid separator for waste water of ready-mixed concrete - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separator having a simple and inexpensive mechanism and high in dehydration rate by furnishing a thickener for naturally settling cement sludge by gravity and a dehydration tank having an inner-cylinder filtration part covered with filter cloth and with plural partition filters implanted in the filtration base plate. SOLUTION: When the waste cleaning water of an agitating truck is treated, the waste water is introduced into a trommel 1 through a truck-washing trough, and the sludge with the aggregate removed therein is put into a sludge tank 2 and then supplied to a thickener 4 with a pump 3. The settled concd. sludge is sent to a dehydration tank 7 under pressure through a slurry pump 6, and the supernatant water is introduced into a filtered water tank 15 from an overflow trough 8. In this case, a filtration base plate 10 is fitted at the bottom of the dehydration tank 7, and an inner cylinder 11 is inserted into the inner periphery of the lower part of the dehydration tank 7. Plural partition filters 12 are arranged on the base plate 10, the cake formed in the inner cylinder is dropped by opening the base plate 10, and the cake is carried out by a truck.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for dewatering sludge after collecting aggregate, mainly in a small-scale ready-mixed concrete factory, by separating the sludge into supernatant water and highly concentrated sludge.

[0002]

2. Description of the Related Art As a conventional method, first, raw corn sludge is put into a thickener, and sedimentation of high-concentration sludge that sediments and supernatant water is mixed to a desired concentration and mixed into the mixing water of raw corn. As another method, high-concentration sludge settled by a thickener is stored in a separate tank, air-dried and treated as regulated industrial waste, and the supernatant water is used as kneading water for ready-mixed concrete. Further, in an apparatus for performing solid-liquid separation similar to the preceding two paragraphs,
Immediately before the sludge is dewatered by a dewatering machine, there is a method that enables the same day dewatering by changing the properties of the slurry by interposing a pretreatment tank (Japanese Patent Application No. 5-355200, Japanese Patent Application No. 5-355228). ). In the earlier application, changing the properties of the slurry means that fine air is mixed into the sludge and bubbles are generated, whereby the admixture mixed in the ready-mixed concrete is entrained by the bubbles and floats, and the bubbles are removed. By removing it, the effect of the admixture is eliminated, and the dehydration is facilitated.

[0003]

SUMMARY OF THE INVENTION
In the method described in the section, since the standing time is long and the water content of the concentrated sludge is as high as 60% to 80%, the compressive strength of the cake is low and it is necessary to treat it as a regulated industrial waste as before. In addition, the conventional filter press dehydrator mechanism requires a filter plate and a pressurizing mechanism, so that the equipment value could not be reduced. Therefore, the present invention respects the function of the thickener and develops a dewatering tank having a simple filtration function that does not require a filter plate opening / closing mechanism. According to the invention of item 2 in which a pretreatment tank according to the application of
This is a dewatering method that considers economy. This method is intended to achieve a water content of the dewatered cake of about 40%, thereby improving the cake strength and obtaining a quality equal to or higher than that of the mortar, so that it can be treated at the same level as general building waste. It is an object of the present invention to provide an economical dewatering apparatus with a simple, inexpensive mechanism, particularly in a small-scale factory.

[0004]

According to a first aspect of the present invention, a thickener for subjecting cement sludge to natural sedimentation by gravity is used as a first step, and a filter cloth is stretched by inserting the thickener into a lower body portion of a vertical cylindrical tank. The inner cylindrical filtration unit provided, and a bottom provided with a filtration bottom plate that opens downward on the bottom surface, the dehydration tank having a filtration structure in which a plurality of partition filtration plates are planted on the filtration bottom plate as the second step, The dewatering tank dewaters the concentrated sludge of the thickener by pressurizing a slurry pump, and separates the solid and liquid by interlocking the two steps.

[0005] In the method of claim 2, a thickener for sedimentation of cement sludge is used as a first step, and the filter is detachably provided on a filter plate having a filter cloth stretched on a lower body portion and a bottom surface of a vertical cylindrical tank. A pretreatment tank is interposed between the second step of the cylindrical dehydration tank having a filtration structure having a plate, and three steps are performed. The pretreatment tank has a stirring longitudinal axis at the center, and a plurality of ejection ports provided on a horizontally rotating air pipe at a lower portion, and has a function of changing the properties of sludge by air ejection. The lower end of the stirring longitudinal axis is provided with an upwardly feeding blade.

[0006]

The operation of the present invention will be described. The washing water and the returned concrete of the ready-mixed concrete carrier are separated into solid and liquid by the aggregate separating device 1, the aggregate is transferred to the aggregate storage tank, and the sludge is once sent to the storage tank 2. From here, it flows into the thickener 4 by the pump 3. The sludge settling in this tank is sent to the dewatering tank 7 by the slurry pump 6 with the discharge valve 5 opened. An overflow toy 8 is provided on the upper edge of the thickener, and the supernatant water overflows to the toy on the circumference and is introduced into the filtered water tank. Adjustment of the inflow amount to the thickener and the water supply amount of the slurry pump 6 is performed by valves 9 and 9 'respectively provided in the water distribution pipes. The bottom surface of the dewatering tank 7 is openable and closable by a filter bottom plate 10 so that it can be opened and closed in one side, and an inner cylinder 11 having a filtering function is inserted in a lower portion, and the inner surface of the inner cylinder has a downward slope. The cake is easy to fall down. A plurality of partition filter plates 12 are planted on the filter bottom plate 10 and detachable from the filter bottom plate. When the filter bottom plate is opened, the partition filter plate is integrally formed with a draft so as to be able to be withdrawn downward. And

A discharge valve 13 is provided in the upper direction of the inner cylinder 11 of the dewatering tank.
Is provided. The amount of water drained from the dewatering tank gradually decreases as the cake layer is created.
1 is adjusted in advance, and the dehydration is terminated when the amount of generated filtration water is reduced to a predetermined value. At the same time as the slurry pump 6 is stopped, the discharge valve 13 is opened and the remaining sludge is returned to the sludge tank 2. When the residual sludge has been discharged, the filter bottom plate 10 is opened, and the cake is placed on a lower cake trolley (not shown).
Drop to During dehydration, filtered water is collected by the filtered water tray 14 and introduced into the filtered water tank 15. When the dehydration is completed, the pan is rotated 90 ° in the horizontal direction by the base axis so that the cake does not hinder falling.

[0008] The present invention utilizes the effect of improving the overall efficiency of the dehydration treatment by considering the characteristics of each step and by combining them in a dehydration treatment.
High treatment efficiency for low-concentration mud. On the other hand, in the pretreatment tank, the effect should be good for treating high-concentration sludge. The cylindrical filtration tank is lower in pressure and lower in performance than the conventional filter press dewatering machine, but by combining the above advantages, it exhibits a sufficient function for wastewater treatment in small factories. .

[0009]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows two steps of a thickener and a dewatering tank.
Figure 2 shows a front system diagram of the described embodiment. FIG. 2 shows a plan view. The washing wastewater of the mixer truck enters the trommel 1 via the carwash toy, and the sludge from which the aggregate has been removed by the trommel enters the sludge tank 2. Water is supplied from the sludge tank 2 to the thickener 4 by the pump 3. A discharge valve 5 is provided at the bottom of the thickener 4, and the precipitated high-concentration sludge is pumped to a dewatering tank 7 by a slurry pump 6. On the other hand, the supernatant water of the thickener 4 is formed so as to be introduced into a filtration water tank from an overflow toy 8 provided in an upper circumferential shape.

The bottom surface of the dewatering tank 7 is provided with a downward, one-sided filter bottom plate 10 having a filtering function on the inner periphery of the lower part of the dewatering tank, and having a downward slope so that the deposited cake can be removed. The provided inner cylinder 11 is inserted. The filtration bottom plate 10 is provided with a plurality of partition filtration plates 12 so that the filtration bottom plate 10 can be simultaneously withdrawn downward when the filtration bottom plate 10 is opened downward. When the dehydration is completed, the residual sludge is returned to the sludge tank 2 by opening the discharge valve 13 provided above. The cake created in the inner cylinder falls down by opening the filtration bottom plate 10 and is carried out by a cake cart (not shown). The filtered water during dehydration is received in the filtered water receiving tray 14 below, and the filtered water tank 1
5 so that when the cake falls,
Swivel to escape from the drop position.

FIG. 7 is a front system diagram of an embodiment according to claim 2, which comprises three steps in which a pretreatment tank is interposed between a thickener and a dehydrator. The structures of the thickener 4 and the dewatering tub 7 are the same as in the above embodiment. The pretreatment tank 16 is connected to the discharge valve 5 of the thickener 4. The sludge pretreated by the pretreatment tank 16 is pumped to the dewatering tank 7 by the slurry pump 6. The internal structure of the pretreatment tank is provided with a stirring shaft 17 having a hollow central portion, and the shaft is provided with a blade 18 near a lower end discharge port. The blades are fed upward to prevent clogging of the outlet. A horizontal horizontal pipe 19 is provided in the upper part,
The horizontal tube is provided with a plurality of nosepieces so that an infinite number of air bubbles are ejected on a horizontal plane as the shaft rotates. The air inlet is connected to the air source at the upper end of the vertical axis. The electrode rod 20 is provided in the pretreatment tank, and the amount of water in the pretreatment tank is adjusted by the discharge valve 5. It has the above structure.

[0012]

[Effect] Since the filter plate and the pressurizing mechanism of the filter plate used in the conventional dewatering method are not required, the equipment cost is about 50% of that of the conventional method, and the water content of the cake is 40%. Because the compression strength can be set to the same level as ordinary mortar because it can be set back and forth, the generation of regulated industrial waste is eliminated, and a significant reduction in processing costs and consideration for environmental issues are achieved. It is.

[Brief description of the drawings]

FIG. 1 is a front system diagram of an embodiment according to claim 1 of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a partial view in the vicinity of a dewatering tank filtration bottom plate.

FIG. 4 is a plan view of a dewatering tank filtration bottom plate.

FIG. 5 is a partial front view of a partition filter plate.

FIG. 6 is a side sectional view of a partition filter plate.

FIG. 7 is a front system diagram of an embodiment according to claim 2 of the present invention.

[Explanation of symbols]

 Reference Signs List 1 trommel 2 storage tank 3 pump 4 thickener 5 discharge valve 6 slurry pump 7 dehydration tank 8 overflow toy 9 valve 9 'valve 10 filtration bottom plate 11 inner cylinder 12 partition filtration plate 13 discharge valve 14 filtered water tray 15 filtration water tank 16 pretreatment tank 17 Stirring longitudinal axis 18 Blade 19 Horizontal horizontal tube 20 Electrode rod 21 Valve

Claims (2)

[Claims] 1. A thickener, which naturally setstles cement sludge by gravity as a first step, an inner cylindrical filtering section in which a filter cloth is stretched on a lower body portion of a vertical cylindrical tank, and a lower surface on a bottom surface. A filtration bottom plate to be opened is provided, and the filtration bottom plate has a dehydration tank having a filtration structure in which a plurality of partition filtration plates are planted as a second step, and the two steps are interlocked to separate solid and liquid. Solid-liquid separation equipment for waste concrete. 2. A thickener for sedimenting cement sludge as a first step, and a dewatering tank having a filtering structure in which a filter cloth is stretched on a lower body portion and a bottom surface of a vertical cylindrical tank during a second step. A solid-liquid separation device for ready-mixed concrete wastewater, wherein a solid-liquid separation device is interlocked as a three-step process by interposing a pretreatment tank having a shaving blade and an air blow horizontal axis on a vertical stirring shaft.