JPH0647690U - Scum removal device in a dirty water tank - Google Patents

Abstract

(57) [Summary] [Purpose] Scum generated is crushed and removed in the pits where submersible pumps are installed in sewage treatment plants and sewage relay stations to prevent sewage in the pits from spoiling. [Structure] In the pit, install a draft tube whose upper end opens in the lower part near the pumping surface of the submersible pump in the pit and whose lower end opens in the vicinity of the suction port of the submersible pump. A branch pipe of the pumping pipe was inserted downward, and an opening / closing valve was provided in this branch pipe. When scum occurs in the pit, part of the pumped water falls by opening the on-off valve and flows in the draft tube, causing the scum near the top opening of the draft tube to be drawn and broken by the blades in the submersible pump. It is discharged and removed together with pumping. No special crushing device is required, and the amount of water flowing down from the pumping pipe is small and it can be operated at low cost.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an improvement of a scum removing device that is generated in a sewage treatment tank in a sewage treatment plant, a relay sewage tank provided in a sewage water passage, and the like.

[0002]

[Prior art]

 Conventionally, as a device for removing scum generated in this type of wastewater tank, there is, for example, Japanese Patent Publication No. 4-56680. In this invention, a draft tube is provided by submerging it in the waste water tank, and the stirring blade is rotated in this draft tube, and the negative pressure generated as a result is used to aspirate the scum on the surface layer of the waste water and at the same time crush and remove it. I am trying to do it.

[0003]

[Problems to be solved by the device]

 However, in the conventional technology, a device for crushing the generated scum and a device for guiding the crushed scum are required, which is difficult to install in a small wastewater tank or the like, and the cost of the device is expensive.

[0004]

[Means for Solving the Problems]

 This invention is characterized by removing the generated scum by utilizing a part of the power of the submersible pump. The gist of the idea is that the submersible tank with the submersible pump is installed. Provide a draft tube for scum suction in the vicinity of the submersible pump, open the upper end of the draft tube near the bottom of the bottom of the bottom of the inflow pipe of the sewage into the sewage tank, and the lower end of the suction tube of the submersible pump. On the other hand, the submersible pump pumping pipe is provided with a branch pipe so that the tip of the branch pipe is opened in the upper end of the draft tube, and an on-off valve is attached to the branch pipe. It was done.

[0005]

The device according to the present invention is configured as described above, and when the valve of the branch pipe is opened and the submersible pump is operated with the water level in the waste water tank lowered to the vicinity of the upper end of the draft tube, the pumped waste water is discharged. A part of it flows through the branch pipe and flows into the draft tube. The inflowing sewage draws the upper layer water of the sewage tank into the draft tube, and the scum generated on the upper layer surface at the same time is drawn into the draft tube. Then, the wastewater containing this scum is crushed by the blades of the submersible pump and discharged to the outside of the tank. In other words, a part of the drainage power of the submersible pump can be used to draw in the scum and discharge it. The drawn scum flows through the branch pipe as well, but since it is crushed by the blades of the submersible pump, the branch pipe will not be blocked. The present invention will be specifically described below with reference to the drawings.

[0006]

【Example】

 In FIG. 1, reference numeral 1 is a sewage tank, 2 is a submersible pump, 3 is a pumping pipe, 4 is a draft tube, and its upper end is located below the water level H1 at the bottom of the sewage inflow pipe 5 into the sewage tank 1. It is opened, and its lower end is opened near the suction port 2 a of the submersible pump 2. The tip end of the branch pipe 3a is inserted into the draft tube 4 for insertion. In the figure, reference numeral 6 is a mount for installing a submersible pump device, and 7 is a mount for installing a draft tube.

The device according to the present invention is configured as described above, and when scum occurs in the waste water tank 1, as shown in the figure, when the water level falls near the bottom of the waste water inflow pipe 5, By opening the on-off valve 3b, part of the pumped water flows down into the draft tube 4. The scum in the vicinity of the upper end opening of the draft tube 4 is drawn into the draft tube 4 by the pressurized flowing water. Then, the scum is sucked by the submersible pump 2, crushed by the blades, and discharged to the outside of the dirty water tank 1.

That is, in this invention, the scum generated in the wastewater tank 1 can be removed by utilizing the submersible pump 2 provided in the wastewater tank 1 and a part of the pumped water. It is possible to prevent spoilage from spoiling and the generation of odor. The device can be manufactured at low cost by only adding the draft tube 4 and the branch pipe 3a without requiring a crushing device. In the case of a large sewage tank, in addition to forming the injector with the branch pipe 3a, a part of the pumped water may be used to push the surface scum toward the draft tube.

[0009]

[Effect of device]

 As described above, the device according to the present invention is a simple device that only adds a draft tube and a branch pipe, and is capable of crushing and removing the scum of a wastewater tank, which has been a problem in the past. However, it is cheap, and the profit that can be obtained in practice is enormous.

[Brief description of drawings]

FIG. 1 is a schematic vertical sectional side view of a scum removing device according to the present invention.

[Explanation of symbols]

 1 Sewage tank 2 Submersible pump 2a Suction port 3 Pumping pipe 3a Branch pipe 3b Open / close valve 4 Draft tube

Claims (1)

[Scope of utility model registration request] 1. A sewage tank 1 in which a submersible pump 2 is installed is provided with a draft tube 4 for sucking scum located near the submersible pump 2, and the upper end of the draft tube 4 is
The inflow pipe of the submersible pump 1 is opened below the bottom water level H1 of the inflow pipe and its lower end is opened near the suction port 2a of the submersible pump 2, while the pump pipe 3 of the submersible pump 2 is opened.
Is provided with a branch pipe 3a, the tip of the branch pipe 3a is opened in the upper end portion of the draft tube 4, and the branch pipe 3 is further provided with an opening / closing valve 3b.