JPH0132116B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a mixing storage tank for uniformly mixing synthetic resin powder produced in large quantities mainly in petrochemical factories, etc., even if the quality is somewhat uneven from lot to lot. It is related to.

Generally, this type of powder (e.g. polyethylene,
Various brands of polypropylene (such as polypropylene) are produced alternately at intervals of 1 to 2 days. Therefore, even if the products of the previous lot and the products of the next lot are produced in the same manner under standard conditions, it is inevitable that the products will be produced with somewhat different quality. As a result, in chemical factories that produce this type of granular material, the granular material for each lot is temporarily stored in a large mixing storage tank, and after being mixed through various means as shown below, It is shipped as a homogenized powder.

The conventional first mixing means for the above-mentioned powder and granules is, for example, to fluidize the powder and granules by simultaneously blowing air while putting each lot of powder and granules into a storage tank with a predetermined diameter. It is mixed inside. However, although this method is suitable for mixing small volumes, for large volumes, it is necessary to blow a large amount of high-pressure air into the entire tank, resulting in high costs.

In addition, as a second mixing means, a powder or granular material input port for each lot is arranged on the storage tank, and the input pipes from each lot are inserted into this storage tank at different heights, and then the powder is inserted from the above pipe. The powder and granules are taken out, collected, and mixed by circulation in the upper part of the tank. However, this method has the problem of high cost because it is necessary to repeat the circulation of the granular material about 3 to 5 times.

Furthermore, as a third mixing means, there is a method that divides the inside of the storage tank into a plurality of storage chambers, sequentially fills each lot with powder and granular material, and then simultaneously takes out a certain amount from each of the chambers and mixes them. However, this method
The configuration for inputting and discharging powder and granular materials is complicated, which increases equipment costs and costs.
There was a problem that the mixing effect was not always good and the quality was not stable.

Further, as a fourth mixing means which is somewhat improved on the third mixing means, an internal extraction cylinder having a row of extraction openings is provided in the storage tank body, each lot is stacked and housed in sequence, and a damper provided in the extraction cylinder is installed. There are devices that discharge water by opening manually or automatically, but even though this has a simpler structure compared to the third mixing means, it is still insufficient, and furthermore, the operation of opening and closing the damper is not sufficient. It was complicated and could not be mixed sufficiently uniformly.

The present invention was made to solve the above problems, and its purpose is to have a simple structure and operation, and to uniformly mix powder and granular materials from each lot without requiring power. The object of the present invention is to provide a mixing storage tank for powder and granular materials that can reduce equipment costs and operating costs, thereby reducing costs. A single inner cylinder is erected concentrically inside the storage tank body consisting of a conical part having an inclination greater than the angle of repose, and a plurality of passages in the axial direction are formed inside the inner cylinder. The lower end of the cylinder is arranged close to the outlet at the lower end of the storage tank main body, each of the passages is exclusively provided with a single extraction hole of different height, and the outlet has an opening smaller than the opening at the lower end of the inner cylinder. The device is characterized in that it is equipped with a complete dispensing device consisting of a slide gate.

In the mixing device of the present invention, when the opening/closing device is opened after the products of each lot are stacked one after another and the storage tank is full, the products of each lot are delivered to each lot from the corresponding extraction hole in the axial direction of the inner cylinder. They simultaneously flow out along the passage and are discharged in a uniformly mixed state through the opening of the slide gate at the lower end. Finally, the storage tank can be completely emptied by removing the slide gate.

Embodiments of the present invention will be described below with reference to the accompanying drawings. The storage tank main body 1 for mixing powder and granular material of synthetic resin material is a vertical cylindrical body, and at the center position of its upper end, which has a rapidly reduced diameter, there is a single hole for introducing the powder and granular material before mixing. One input port 3 is installed. The lower part of the storage tank body 1 is gradually reduced in diameter from the middle to form a conical part 1a having an inclination larger than the angle of repose, and a single outlet for discharging the powder and granular material is provided at the center of the lower end. 4 is installed. At the center inside the storage tank body 1, there is an inner cylinder 2 shown below.
Its upper end is located a little apart from the input port 3, and its lower end is located close to the discharge port 4 so as to be concentric with and perpendicular to the storage tank body 1. The inner cylinder 2 can be fixed to the storage tank body 1 by appropriate means. It is recommended that the storage tank body and the inner cylinder 2 be made of a smooth and rustless material, such as stainless steel.

The inner cylinder 2 is a cylindrical body with a predetermined diameter, and its upper end is closed to form a conical part 2a having an inclination larger than the angle of repose, which helps in smoothly dispersing the powder and granules. As shown in FIG. 3, a small diameter cylinder 5 is housed concentrically inside the inner cylinder 2.
The annular space formed between the inner cylinder 2 and the cylinder 5 is divided equally by a plurality of partition plates 6, 6, . . . , and passages 7A, 7B, 7C, .
Configure 7N. To assemble the inner cylinder 2, first,
Partition plates 6, 6, . . . are welded to the cylinder 5, and the partition plates 6, 6, . . . are tightly fitted to the inner wall of the inner cylinder 2. Each aisle 7
Single extraction hole 8 for each of A, 7B, 7C, ...
A, 8B, 8C, ... will be provided exclusively. In the embodiment shown in FIGS. 2 and 3, each extraction hole 8A, 8
B, 8C, . . . are provided at lower positions by a vertical height h in the clockwise direction when viewed from above.

FIGS. 4 and 5 show other embodiments, in which the extraction holes 8A face each other (positions with a phase difference of 180°).
An extraction hole 8B' lower by height h is provided in the extraction hole 8B'.
An extraction hole 8C' which is h lower than the extraction hole 8B' is provided at a position having a phase difference approximately between A' and 8B', and an extraction hole 8C' which is h lower than the extraction hole 8B' is provided at a position opposite to the extraction hole 8C'.
D′ is provided. When a powder or granule is discharged from a certain extraction hole, as the discharge progresses, the discharge stops at a position where the powder or granule forms an angle of repose with respect to the extraction hole.
In this embodiment, since the extraction holes are arranged as described above, the half-cone-shaped curved surfaces appear sequentially at positions facing each extraction hole, and a smooth discharge operation proceeds.

FIG. 6 is an enlarged sectional view of the lower part of the storage tank body 1. A cylindrical portion 1b is formed at the lower end of the storage tank body 1,
A slide gate 9 having an opening 10 is provided in the cylindrical portion 1b. The slide gate 9 is operated by a slide gate operating section 11 and moves in a horizontal plane to open and close the discharge port 4. The diameter d of the opening 10 provided in the slide gate 9 is smaller than the inner diameter opening of the cylindrical portion 2b formed at the lower end of the inner cylinder 2. It is also possible to provide an appropriate number of notched holes as necessary for the powder to extract the conical portion 2c formed above the cylindrical portion 2b.

FIG. 7 shows another embodiment of the inner cylinder 2, in which gutter-like members 13, 13, . 7B″,
7C'',... is constructed.

Since the powder and granule mixing storage tank according to the present invention is configured as described above, when mixing synthetic resin powder and granules according to each lot (not shown) in the mixing storage tank, the powder and granule are transferred to the input port 3. The liquid is continuously introduced into the storage tank body 1 from the beginning to the end. Powder and granular materials have non-uniform quality due to subtle differences in operating conditions during the manufacturing process, and quality also differs depending on the height, so each extraction hole 8A, 8B,... 8A', 8B'..., powder and granules of different quality enter the inner cylinder 2 from the above-mentioned extraction holes at each position. The inner cylinder of the inner cylinder 2 has respective extraction holes 8A, 8B,
Since the passages 7A, 7B, etc. are independent for each..., the powder and granules at each height do not flow down preferentially, and the powder and granules at each height are The uniformly mixed powder and granular material can be smoothly and easily discharged from the discharge port 4 where the passages 7A, 7B, . . . communicate with the extraction holes 8A, 8B, . . . at the lower end. .

According to one embodiment, the inner diameter of the storage tank body 1 is 700 mm,
The height is 3300 mm (straight body part 2500 mm, conical part 800 mm), and an inner cylinder 2 with a diameter of 150 mm is provided inside this main body 1. Divided into minutes, each passage 7A, 7
B, . . . and these passages 7A, 7B, .
… 300 extraction holes 8A, 8B, … each with a diameter of 60 mm
They were placed at equal intervals of mm.

FIG. 6 is an enlarged sectional view of the vicinity of the discharge port 4, showing a complete discharging device for powder and granular material. When the slide gate 9 is closed, the opening 1 of the slide gate 9
Since the diameter d of 0 is smaller than the inner diameter D of the inner cylindrical part 2b of the inner cylinder 2, the annular passage between the cylindrical part 1b and the cylindrical part 2b is narrow, and this makes it difficult to support the powder or granular material. Therefore, the powder always flows into the inner cylinder 2 from the extraction hole and then is discharged from the discharge port 4. When the discharging operation of the powder approaches the final stage, operate the slide gate operating section 11 to close the slide gate 9.
When the tank is fully opened, all the powder and granules accumulated in the conical portion 1a are discharged, and no powder remains in the storage tank body.

Figures 8 and 9 show mixing tests according to the invention. When three types of colored blue pellets P ₃ , white pellets P ₂ and red pellets P ₁ (diameter ≒ 4 mm) were sequentially charged into each 150 kg from the input port 3 of the storage tank body 1 (Fig. 8), the bottom end As shown in FIG. 9, mixed pellets of each color were obtained from the discharge port 4 at a good mixing ratio that was approximately proportional to the input amount.

The mixing tank of the present invention provides mixed pellets of uniform quality by performing an effective mixing action without requiring any power. Furthermore, the mixing storage tank of the present invention has a simple structure and operation, and is easy to manufacture, and by providing a single inner cylinder concentrically with the storage tank body, it has no problems compared to a mixing storage tank with multiple inner cylinders. Comparably homogeneous mixed pellets are obtained.

[Brief explanation of drawings]

Fig. 1 is an overall view of the mixing storage tank, Fig. 2 is a partially enlarged view of the inner cylinder, Fig. 3 is a sectional view taken along the - line in Fig. 2, and Fig. 4 is a partially enlarged view of the inner cylinder of another embodiment. Figure 5 is a sectional view taken along line V-V in Figure 4, Figure 6 is an enlarged sectional view of the lower end of the storage tank body, Figure 7 is a sectional view of the inner cylinder of another embodiment, and Figure 8 is An explanatory diagram of the mixing test, FIG. 9 is a graph showing the results of the mixing test.

Claims (1)

[Claims] 1. A single inner cylinder is erected concentrically inside a storage tank body consisting of a cylindrical part and a conical part having an inclination greater than the angle of repose following the cylindrical part, and a plurality of shafts are installed inside the inner cylinder. A central passage is formed, the lower end of the inner cylinder is arranged close to the outlet at the lower end of the storage tank body, each passage is exclusively provided with a single extraction hole of different height, and the outlet is provided with a single extraction hole having a different height. A mixing storage tank for powder and granular material, characterized in that it is provided with a complete dispensing device consisting of a slide gate having an opening smaller than the opening at the lower end of the inner cylinder.