JPS6242664B2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to a centrifugal concentrator, which improves the recovery rate of solids when separating a raw solution containing solids such as sludge generated from sewage treatment facilities into solids and clear water. The purpose is to improve.

Conventionally, devices used for this purpose include:
The rotating cylinder for centrifugally concentrating solids is a single-stage type with a constant diameter, and the separation of solids is not sufficient, and some of the solids are lost to clear water.

In order to improve the clarity, the present invention uses a two-stage rotary cylinder for centrifugally concentrating solids by connecting a small-diameter cylinder and a large-diameter cylinder. The clarified water, which has been separated and whose clarity is still insufficient, is made to flow into a large-diameter cylindrical body to apply a larger centrifugal force and to obtain sufficient recovery of solids.

Embodiments of the present invention will be described below based on the drawings. In FIG. 1, a first cylindrical body 1 is rotatably provided around its axis, and a wall plate 3 extending radially inward is provided at one end 2, and a wall plate 3 extending radially outward is provided at the other end 4. A facing wall plate 5 is provided. The second cylindrical body 6 is formed to have a larger diameter than the first cylindrical body 1, and one end 7 thereof is connected to the wall plate 5. Further, at the other end 4 of the first cylindrical body 1, a first tube extending inward in the radial direction is provided.
A second overflow weir 8 is provided at the other end 9 of the second cylindrical body 6, and a second overflow weir 10 that extends radially inward and has a larger diameter than the first overflow weir 8 is provided. ing. 1
2 is a stock solution supply pipe inserted near the bottom of the first cylinder 1, 13 is a concentrated solids discharge pipe of the first cylinder 1, and 14 is a concentrated solids discharge pipe of the second cylinder 6. It is a discharge pipe.

The stock solution supplied from the stock solution supply pipe 12 is subjected to centrifugal force by the first cylinder 1, and the solids A are separated and deposited on the wall of the cylinder 1. On the other hand, the clear water B from which the solids have been separated does not completely separate the solids, and flows out of the overflow weir 8 and into the second cylindrical body 6 while still containing some solids. FIG. 3 is a graph showing the relationship between centrifugal force and solid matter recovery rate. Therefore, the solid matter lost in the first cylinder 1 is subjected to a larger centrifugal force by the second cylinder 6 than in the first cylinder 1, since the centrifugal force is proportional to the size of the radius. Further, the solid matter C is separated, a very high solid matter recovery rate is obtained as a whole, and the clarity of the clear water D is improved. The clear water D then flows out of the system from the overflow weir 10. On the other hand, solids A and C are each discharge pipe 1.
3 and 14, and is discharged outside the cylinders 1 and 6. Note that the capacities of the first cylindrical body 1 and the second cylindrical body 6 at this time may be of a size proportional to the amount of solids collected in each of the cylindrical bodies 1 and 6. Therefore, since most of the solids are recovered in the first cylinder 1, the capacity of the second cylinder 6 can be considerably smaller than that of the first cylinder 1, and therefore a reasonable solids Recovery is obtained. Further, the discharge pipe 14 is not necessarily provided, and the solid matter C in the second cylinder body 6 can be discharged by the discharge pipe 13.

FIG. 2 shows another embodiment according to the invention. Compared to the case shown in FIG. 1, the first cylindrical body 1 and the second cylindrical body 6 are installed upside down, and the undiluted solution supplied from the undiluted solution supply pipe 13 is rotated by the rotation of the cylindrical body 16. The solids fall onto a disk 17 attached to the top of the shaft 16 and are transferred to the peripheral wall of the first cylindrical body 1 due to centrifugal force, whereupon the solids are centrifugally concentrated as in the case of FIG. Further, although what is shown in FIGS. 1 and 2 is a vertical type with the axis set in the vertical direction, the same effect can be obtained even if it is a horizontal type with the axis set in the horizontal direction.

As is clear from the above description, the present invention uses a two-stage rotary cylinder for centrifuging the solids contained in the stock solution, in which a small-diameter cylinder and a large-diameter cylinder are connected. By supplying the undiluted solution to the body, the solids that cannot be recovered by the small-diameter cylinder are collected by applying a large centrifugal force to the large-diameter cylinder, so a very high solids recovery rate can be achieved. It will be done.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view showing one embodiment of the centrifugal concentrator of the present invention, Fig. 2 is a longitudinal cross-sectional view of a centrifugal concentrator showing another example of the present invention, and Fig. 3 is a longitudinal cross-sectional view showing centrifugal force and solid matter. It is a graph showing recovery rate. 1... First cylindrical body, 3, 5... Wall plate, 6... Second cylindrical body, 8... First overflow weir, 10... Second overflow weir.

Claims (1)

[Claims] 1. A first cylindrical body rotatable about its axis is provided with a wall plate extending radially inward at one end, and a second cylindrical body having a larger diameter than the cylindrical body is provided at the other end with a wall plate extending radially outward. a first overflow weir extending radially inward at the other end of the first cylindrical body, and a first overflow weir extending radially inward at the other end of the second cylindrical body A second overflow weir having a larger diameter than the overflow weir is provided, and a concentrate supply pipe capable of supplying the concentrate into the first cylinder is inserted into the first cylinder. centrifugal concentrator.