JPS591994Y2 - Pump circulating slurry storage tank - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slurry storage tank that maintains a slurry suspended in settleable solids in a homogeneous state.

Conventionally, when transporting coal, iron ore, non-ferrous metals, etc., transportation means such as freight cars, trucks, and belt conveyors have been used.

However, loading and unloading requires a lot of time and manpower, and the above-mentioned materials are suitable for pipeline transportation, so methods of suspending them in water and transporting them through pipes are becoming more popular.

Therefore, it is necessary to store a large amount of these slurries in storage tanks for a considerable period of time at intermediate stations and receiving stations, and the storage tanks used for this purpose range in size from about 1,000 to 50,000.

It is important to maintain a uniform composition of the slurry in these storage tanks.

For example, if suspended solids settle and the slurry cannot be continuously extracted, the continuous supply of raw materials for the process will be interrupted and operations will not be possible, and even if continuous supply is possible, the solids in the slurry will When concentration changes are severe, it becomes very difficult to operate a process that accommodates these changes.

However, in this slurry transportation, when the solids are suspended in water to a predetermined solids concentration with a constant particle size, the particles interfere with each other and the sedimentation rate of the suspended solids becomes very slow.

At this time, it is effective to add a surfactant to prevent the solid matter from settling, but since surfactants are expensive, this is economically disadvantageous.

The settling rate of solids in these slurries is usually 0.1 to 1
．． Since the moving speed is adjusted to 0 m/Hr, the moving speed should be set to 1. It is sufficient to maintain it above Qm/Hr.

In order to maintain this moving speed, methods such as installing a propeller-type stirrer on the side of the storage tank or inserting a stirrer from the top to stir and move the slurry have been used to stir the storage tank.

However, the former has disadvantages such as when the tank becomes large, the stirring power does not reach the center of the tank, and solids accumulate at the bottom of the center.
This tendency is particularly exacerbated when a highly viscous liquid such as heavy oil is used, so there is a limit to the size of the storage tank to which a stirring method with a propeller stirrer on the side can be applied.

Further, in the latter method of introducing an agitator from the top, a power of 1 to 2 KW/m2 is required to agitate the entire thick slurry in the tank using, for example, a turbine type agitator.

However, depending on the type of substance, slurry with a certain particle size and solid concentration can be stored in a large storage tank by moving the liquid slowly at a certain speed or higher without vigorously stirring the entire slurry. It was discovered that the slurry could be kept homogeneous as long as there was no significant drift.

The present invention was completed based on this knowledge, and eliminates the drifting current that tends to occur in large storage tanks, or even if drifting occurs, it quickly removes the sediment that forms at the bottom of the storage tank to the outside. The purpose is to maintain the slurry homogeneously by dispersing it evenly from the top of the storage tank roof to the top surface of the slurry inside the storage tank.
It can be economically applied to large-sized storage tanks.

This invention will be explained in detail below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, in which 1 is a cylindrical, flat-bottomed slurry storage tank with a roof.

A hollow cylindrical tower 1b is installed vertically in the center of the bottom plate 1a of the slurry storage tank 1 in close contact with the tower 1b, and the upper part of the tower 1b penetrates through the roof 1C of the slurry storage tank. A canopy 1d is fixed to the roof 1C by a fastener 1e, covering the upper end opening of the tower 1b.

A drive device 2 is provided on the upper outer periphery of the tower 1b, and the rake arm 2b is driven by the driving force of the drive device 2 via a connecting member 2a.

A rake 2C is attached to the lower part of the rake arm 2b for scraping the thick slurry or solid matter that has settled on the bottom plate 1a around the lower end of the column 1b.

Further, on the bottom plate 1a at the lower end of the column 1b, a slurry circulation system 3 is provided.
A pump 3a is provided as a driving source for the tower, and the slurry or solid matter gathered around the bottom end of the tower is extracted by the pump 3a inside the hollow columnar tower fixed to the slurry storage tank bottom plate 1a, and is pumped through the roof 1C via piping 3b. is introduced into the inside of the pipe cover 30 provided on the top of the pipe.

Inside the pipe cover 30, a guide pipe 3d supported by a support 1f fixed to the side surface of the storage tank 1 is vertically provided.

Note that 3e is a slurry introduction pipe. Figure 2 shows tower 1
2d is a vertical cross-sectional view of the drive device 2 provided on the upper part of the column 1b, and 2d is a metal fitting provided on the circumference of the tower 1b.

For installation, the casing body 2e of the drive device 2 is attached to the metal fitting 2d.
is fixed, a cover 2f is attached thereon, an electric motor 2f with a reduction gear having a pinion gear 2g is provided on the cover 2f, and It meshes with the provided internal gear 2.

A sealing member 21 is provided between the outer periphery of the shaft fixing member 2j and the tank roof IC to isolate the inside of the storage tank from outside air.

Further, a sealing material 2m is provided between the casing 2e and the shaft fixing member 2j to seal the storage tank.

A connecting member 2a is attached to the lower part of the shaft fixing member 2j.

FIG. 3 shows another embodiment of the present invention, in which the circulation system pump 3a is not placed inside the column 1b but outside the storage tank, and the concentrated liquid is collected toward the outer circumference of the lower end of the column 1b. Slurry or solid matter is taken out through the lower piping of the bottom plate 1a provided close to the outer periphery of the hollow columnar column 1b, and is taken out from the ground 4.
It is circulated to the upper part of the storage tank by a pump 3a through piping in a tunnel 5 provided in the tank.

Next, the operation of the slurry storage tank according to the invention constructed in this way will be explained.

In general, the method of supporting the roof 1C of a large storage tank is an important element for economically designing roof members, but in this invention, since the hollow columnar tower 1b exists as a pillar in the center, the roof 1C is One side of the support beam is shortened, allowing for a strong and economical design.

A drive device 2 is provided around the upper part of the tower 1b, and a metal fitting 2d,
The shaft fixing member 2j installed via the casing body 2e and the bearing 21 is rotated.

This shaft fixing member 2j drives the rake arm 2b via the connecting member 2a, and scrapes the thick slurry and solid matter settling at the bottom of the storage tank 1 around the lower end of the tower 1b.

Since the rake arm 2b and the drive device 2 that drives it are all supported by the tower 1b in this way, the weight of the thin tube is not applied to the storage tank roof 1C, so that an economical design is possible.

Furthermore, a sealing member 21. Since 2 m of sealing material is provided, the storage tank is completely sealed.

The thick slurry collected around the lower end of the column 1b is sent to the upper part of the storage tank by the circulation system 3 to keep the slurry in the storage tank 1 homogeneous.

At this time, as mentioned above, the moving speed of the slurry is 1. Qm/
If the slurry is made more than Hr, the homogeneity of the slurry will be maintained.
It is necessary to use the capacity and number of pumps that satisfy this condition.

Further, the pump may be installed anywhere as long as the suction port opens near the lower outer periphery of the tower 1.

The thick slurry being sent by the pump 3a is introduced into a pipe cover 3C provided on the roof 1C, and is dropped onto the liquid level of the storage tank 1 along the guide pipe 3d.

The position and number of the guide pipes 3d are determined by the size and height of the storage tank.
Depending on the position of the average liquid level, it is selected as appropriate so as not to cause a drift in the storage tank 1, but since the present invention is of the central scraping type, it is preferable to arrange the guide pipes to the outside.

With this guide pipe, the slurry reaches the liquid surface quietly and is dispersed. However, if the guide pipe is not installed, the slurry will fall directly from the roof to the liquid surface, causing vibrations to the side panels of the storage tank, producing sound and causing repetitive stress. This is not desirable in terms of noise prevention.

Since the slurry that falls in this way is not stirred throughout the storage tank, it descends almost vertically and reaches the pump suction part through the bottom.
Slurry tends to stay near the bottom, so a rake moves it to the center to keep the slurry concentration supplied by the pump constant, and it is circulated to the storage tank liquid level to maintain homogeneity of the slurry in the storage tank. It is something.

The slurry to be supplied to the storage tank is preferably supplied to the circulation system 3 via the conduit 3e, but it may also be provided on the side surface of the storage tank.

As mentioned above, the present invention is a slurry storage tank that includes a central part, a driving device attached to the central part, a rake driven by the driving device, and a guide pipe in the circulation system, which simplifies the storage tank roof structure. It has many advantages such as being economical and making it possible to manufacture a large storage tank without noise, and the power cost is 0.01~0.02KW per 1 ton of stored material, which is much lower than other slurry storage tanks. It is something that you have.

[Brief explanation of drawings]

Fig. 1 is a vertical sectional view of a storage tank showing one embodiment of the present invention;
The figure is an explanatory view of the drive device, and FIG. 3 is a longitudinal sectional view of a storage tank showing another embodiment of the present invention. 1... Storage tank, 2... Drive device, 3...
...Circulatory system, 1a...Bottom plate, 1b...
...Hollow columnar tower, 1C... Roof, 1d...
・・・Cover, 1e... Stopper, 1f...
...Support body, 2a...Connecting member, 2b...
...Rake arm, 2C...Rake, 2d...
...Mounting with metal fittings, 2e...Casing body, 2f...Cover, 2g...Pinion gear, 2h...Electric motor with reducer, 21. ...
...Bearing, 2j...Shaft fixing member, 2k
...Internal gear, 21...Sealing member, 2m...Sealing material, 3a...Pump, 3b...Piping, 3C... ...Pipe cover, 3d...Guidance pipe, 3e...
·conduit.

Claims (1)

[Scope of utility model registration request] A cylindrical, flat-bottomed slurry storage tank with a roof includes a hollow column-shaped tower whose lower end is fixed to the center of the slurry storage tank bottom plate and whose upper end penetrates the roof, and which is driven by a drive device provided on the outer periphery of the upper part of this tower. a rake arm attached to the lower part of the rake arm to scrape the sedimentary solids on the bottom plate of the slurry storage tank to the outer periphery of the lower part of the tower;
The tower has a pump that circulates the settled solids collected on the outer periphery of the lower part of the tower to the upper surface of the slurry in the slurry storage tank, and a slurry guide pipe that is installed perpendicularly from the roof and guides the circulating slurry to the slurry surface of the storage tank. A pump circulating slurry storage tank featuring: