JPS6161877B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pumping device for solids-containing wastewater.

Washing water, cooling water, etc. generated by various industrial facilities are first collected in a pumping pit and sent to wastewater treatment facilities using sand pumps, etc., but solid matter specific to each facility flows into the pumping pit. Even if the sand pump is operated, the suction water flow of the pump is only able to remove the solids around the suction port, so the amount of solids deposited gradually increases and eventually the pump suction port is removed. There is a problem that the water can become clogged, making it impossible to pump water. In order to prevent such a situation from occurring, conventional methods have been to attach a stirring blade below the pump suction port or to inject pressurized water from a separate nozzle for stirring.
In the former case, not only is it not completely effective, but it is also not possible to prevent accumulation in the entire pumping pit, and even in the latter case, a large amount of power and water is required to prevent accumulation in the entire pumping pit. There is a problem that.

Therefore, the present invention aims to provide a pumping device for solids-containing wastewater that can pump up all the solids contained by effectively utilizing the energy of falling water without requiring separate power or water. The gist of this is that a roughly truncated conical protrusion is formed at approximately the center of the inner bottom surface of the pumping pit, and the diameter gradually decreases as it goes upwards, and a low water level is formed directly above the truncated conical protrusion. The suction port of the operable sand pump is opened, and the corner of the inner bottom surface of the pumping pit around the substantially truncated conical projection is made to have a downward slope sufficient to cause the contained solids to flow down by the inflow water force,
There is provided a pumping device for solids-containing wastewater, characterized in that the water level around the sand pump is such that the pump is operated at a low water level near the pump casing of the sand pump. Note that the above-mentioned downward slope of the inner bottom corner of the pumping pit may be a linear slope, a circularly curved slope, or any of the above.

Embodiments of the present invention will be described in detail below based on the drawings.

Figures 1 and 2 show an embodiment of the present invention that utilizes an existing large-scale water pumping pit. A new small-sized pumping pit 1 is formed in the inner bottom surface 3 of the pumping pit 1.
A substantially truncated conical protrusion 4 whose diameter gradually decreases as it goes upward is formed in the substantially central part of the , and a sand pump 5 is provided directly above the substantially truncated conical protrusion 4 .
The suction port 6 is opened, and the substantially truncated conical projection 4 is opened.
The corner portion 7 of the inner bottom surface of the pumping pit 1 around the pumping pit 1 has a downward slope sufficient to cause the contained solids to flow down by the inflow water force.

Since this embodiment has the above configuration, the wastewater containing solids that has flowed into the large pumping pit 1' through the large number of inlets 2 is forced into the pumping pit 1 through the opening edge of the smaller pumping pit 1. As it flows down well, it is guided by the inner bottom corner part 7 of the pumping pit which has a sufficient downward slope, and flows forcefully toward the center of the pumping pit 1, and is guided to the substantially truncated conical protrusion 4 protruding from the center. The water is smoothly sucked into the suction port 6 of the sand pump 5, which opens directly above it, and is pumped up, and this water force prevents the contained solids from accumulating in the pumping pit 1. do not have.

In this case, if the water level in the pumping pit 1 is high, the water force at the inner bottom of the pumping pit 1 will weaken and the solids will accumulate, so a sand pump with a pumping capacity larger than the amount of inflowing wastewater is used to keep the water level low. However, with conventional sand pumps, the air sucked in with the water remains in the impeller, causing an air lock phenomenon, making it impossible to pump water. It is necessary to use a sand pump capable of continuous operation (for example, see patent application (A) ``Vertical shaft type pump for Narumi operation'' = Japanese Patent Application Laid-open No. 1983-32997 filed on the same day).

In addition, it is preferable to make the inner bottom surface of the existing water pumping pit 1' a sloped surface as shown by the dashed line in FIG. 2, in order to effectively utilize the falling energy of the water and to avoid the accumulation of contained solids. be. Although the shape of the pumping pit 1 is preferably circular so that the flow is uniform and smooth, a square shape as shown in the drawings of the embodiment can also be sufficiently effective and advantageous in manufacturing.

As explained in detail above, according to the present invention, the inner bottom corner of the pumping pit has a downward slope that allows solids to flow down sufficiently, and the water level around the pump is low to the vicinity of the pump casing.
In addition, since a roughly truncated conical protrusion is placed directly below the pump, the inflowing solids-containing water, along with the small amount of water stored there, is rapidly reversed and rises, causing constant agitation and solids to accumulate. It can be sucked in efficiently from the pump suction port. Therefore, there is no need for extra power or large amounts of agitating water as in the past, and running costs can be significantly reduced.Especially in the case of new installations, the equipment can be significantly downsized and space can be used more effectively. It has many effects.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view taken along the line of FIG. 1. In the figure, 1...pumping pit, 3...inner bottom surface, 4...
...Approximately truncated conical projection, 5...Sand pump, 6...
Suction port, 7... Inner bottom corner part.

Claims (1)

[Claims] 1. A substantially truncated conical projection whose diameter gradually decreases as it goes upwards is formed at approximately the center of the inner bottom surface of the pumping pit, and a sand pump capable of operating at a low water level is installed directly above the truncated conical projection. At the same time as opening the mouth, the inner bottom corner of the pumping pit around the truncated conical projection is made to have a downward slope sufficient to cause the contained solids to flow down due to the inflow water force, so that the water level around the sand pump is lower than the pump of the sand pump. A pumping device for wastewater containing solids, characterized in that the pump operates at a low water level near the casing.