JPS59278B2 - flotation separation device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a flotation separation device for separating a specific substance from an aqueous liquid such as wastewater containing suspended or sedimentary substances.

Flotation separation methods used for wastewater treatment include (1)
Two types are known: , bubble contact type, and (2) bubble precipitation type.Furthermore, the former type includes stirring type, air blowing type,
The latter type includes a reduced pressure type and a pressurized type.

However, even when adopting these collapse methods, the most important thing is to form the specific substance into an aggregation flank that is easy to float. (1) In the conventional bubble contact type,
Not only is the floating speed during operation slow, but a large space is required to install the processing equipment, and (2) with the conventional bubble deposition type, the structure of the processing equipment is complicated, resulting in high equipment costs. Both types had many drawbacks.

The present invention has been made to eliminate the above-mentioned drawbacks, and the purpose of the present invention is to eliminate various specific substances that have extremely poor sedimentation properties, such as colloidal iron hydroxide and aluminum hydroxide. It is an object of the present invention to provide a flotation separation device which effectively performs a separation operation even on contained wastewater and which has a simple structure and is inexpensive.

The present invention will be described below based on an illustrated embodiment.

A storage tank 1 for raw water to be treated is installed at the upstream end of the wastewater treatment system, and this tank 1 already contains a foaming agent such as a surfactant, or contains a foaming agent such as a surfactant beforehand. The foaming agent is added and raw water containing the foaming agent is stored.

A small feed tank 2 is attached above this tank 1, and the pump 3 pumps up raw water and the return pipe 4 circulates the overflow.
A constant head H of raw water is always stored inside.

Furthermore, a box-shaped separation tank 5 whose inflow side is partitioned by a partition plate 5a is installed at the downstream end of the treatment system. A lip 5b is formed, and a drain pipe 5C is attached to the floor on the downstream side.

Raw water is fed from the feed tank 2 to the floor on the inflow side of the separation tank 5 via a series of water pipes 6, 7, 8. ,8
This is done by a pump 10 interposed between them.

Incidentally, between the water pipes 6 and 7 and between the water pipes 8 and 9, front and rear intake pipes 11 and 12 each made of a T-tube are covered with valve lids, and the upward passage holes 11a of each intake pipe.

12a opens to the outside air at a height near the fixed head H at a higher position than the pump 10 via a regulating valve 13.14.

In addition, each intake pipe 11.12 has an addition hole 11b through which a polymer flocculant diluted to a low concentration is supplied.

12b is attached, and a control valve 15 for adjusting the water supply flow rate is interposed in the water pipe 6.

Note that the diameter of the water supply pipe 9 on the downstream side of the pump 10 is set to be larger than the diameter of the other pipes 6, 7.8 for the purpose of reducing the flow rate and thereby achieving a flocculating effect of the specific substance.

Next, the operation of the embodiment separator constructed as above will be described.

First, when operating the device, by adjusting the opening degree of the control valve 15 and the opening degree of each of the regulating valves 13 and 14 in conjunction with each other, an appropriate amount of air is supplied from the outside to the regulating valves 13 and 14 of the intake pipe. Operate so that it is mixed into raw water.

Note that such an operation is extremely easy because the water supply head is at a constant H level and the intake pipe is located at a higher position than the pump 10, and the intake flow rate of outside air is maintained accurately.

Due to this suction operation, an appropriate amount of air bubbles and flocculant are mixed into the supplied raw water, and with the help of a decrease in the flow velocity in the water pipe 9, the specific substance is effectively turned into foam in the water pipe 9. Generated by scum**.

Therefore, at the time the raw water flows into the separation tank 5,
Agglomerated scum surfaces almost instantaneously, and after the fact, scum is
The specific substances are compressed and overcrowded as they are swept over the surface layer in the tank 5, and are further drained to the outside beyond the lip 5b, whereby the specific substances are quickly and effectively separated from the raw water.
Exhausted from the system.

In addition, if a part of the treated water is allowed to flow into the suction side of the pump 10 via the return pipe 16, as shown by the chain line in the figure, there is an advantage in contributing to saving on the foaming agent to be added to the raw water.

Here, the test results of the example separation apparatus conducted by the inventor of the present application will be explained.

(Test example, part-) Test raw water...Iron hydroxide 30011+) [11-containing water (
A caustic soda aqueous solution was added to an aqueous solution of ferrous sulfate to adjust the pH to 6 or 8) Added foaming agent: Ripon (trade name) 201) Added flocculant: Bimorok M-366 (trade name) 100p
Water supply flow rate: 1.2rrl'/H (Test example, part 2) Test raw water: First solution with pH 3.3, which is made by adding sulfuric acid to barrel polishing waste water from an operating factory, and aluminum sulfate aqueous solution of 700 pP. Aqueous liquid mixed with second liquid, (pH 6, 8), etc.
...Same results as in Example 1. The effectiveness of the separation device of the example was confirmed by the above results.

As described above, according to the flotation separation device according to the present invention, the treated raw water tank and the flotation separation tank are arranged in series, and the air and flocculant are mixed into the water pipe between the two tanks. Therefore, using a device with a relatively simple and inexpensive structure, it is possible to quickly and effectively generate scum of a specific substance and effectively float and separate it.
This has a great effect on improving the practicality and economic efficiency of the device.

[Brief explanation of drawings]

The figure is a schematic diagram of a flotation separation device showing an embodiment of the present invention. 1...Treatment raw water tank, H...Constant head, 2...Feed tank, 4...Separation tank, 6,7゜8.9...・・・・Water pipe, 10・
...Pump, 11.12...Intake pipe, I
la, 12a...through hole, 11b. 12b... Addition hole.

Claims (1)

[Claims] 1. In a flotation separator that separates specific substances from water such as wastewater containing suspended or sedimentary specific substances, a treated raw water tank and a separation tank that overflows the scum floating on the surface layer, A water pipe installed in the middle of the flow path of the water liquid and equipped with a pump is used to feed the water liquid from the raw water tank to the separation tank, and the water pipe is installed at least in front of the pump. An intake pipe is placed in the middle of the air, and a hole in this intake pipe is opened to the air, and an additive pJL to which a polymer flocculant is supplied is attached to the intake pipe. A flotation separation device characterized in that air bubbles and a flocculant are mixed into the aqueous liquid to promote scum formation of the specific substance, thereby facilitating the floating of the scum in the separation tank.