JPH04215887A - Flocculation and separation apparatus - Google Patents

Abstract

PURPOSE:To provide the title apparatus capable of reducing an installation space and energy consumption. CONSTITUTION:A plurality of chambers 3 are formed in a water treatment tank 1 and allowed to communicate with each other to form a circulating flow path in series. A supply pipe 17 for water to be treated and a flocculant supply pipe 18 are provided to one chamber 3 and a submerged stirring blade 16 is also provided to form a mixing tank while a membrane module 6 is arranged to the other proper chamber 3 so that the membrane surface thereof is provided along the flow direction of water 24 to be treated. The water stream generated by the submerged stirring blade for stirring and mixing a flocculant and water to be treated can be utilized in the washing of a separation membrane and it is unnecessary to separately use power in order to wash the membrane surface and energy consumption can be reduced.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coagulation separation apparatus for treating sewage water such as highly concentrated organic waste liquid.

0002

[Prior Art] Conventionally, in treatment facilities that biologically digest sewage water containing a high concentration of organic matter and further separate solid-liquid, the water to be treated is first supplied to a mixing tank, and the water is mixed in the mixing tank. The treated water is stirred while adding a flocculant, and is then pressure-fed from a pump tank connected to the mixing tank to a cross-flow internal pressure membrane separator using a circulation pump, where it is separated into solids and liquids. was. This cross-flow internal pressure type membrane separator has a narrow flow path, resulting in a large pressure loss, and uses a pump with a high head and small flow rate to pump the water to be treated at a high membrane surface flow rate and high pressure.

0003

[Problems to be Solved by the Invention] However, according to the above-mentioned conventional configuration, the mixing tank, the pump tank, and the membrane separation device are each provided separately, so the installation space becomes large, and the stirring device in the mixing tank is This method requires a circulation pump for supplying water to be treated to the cross-flow internal pressure type membrane separation device, and there is a problem in that it is not possible to use the drive device for both purposes, and it is not possible to save energy consumption.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a coagulation separation device that can reduce installation space and energy consumption.

[0005]

[Means for Solving the Problems] In order to solve the above problems, the coagulation separation device of the present invention has a plurality of chambers formed in a treated water tank, and a flow path that communicates each adjacent chamber and circulates in series. A water supply pipe and a flocculant supply pipe are installed in one chamber, and an underwater stirring blade is installed to form a mixing tank, and a membrane module is installed in another appropriate chamber so that the membrane surface is in the flow direction of the water to be treated. The structure is arranged along the following lines.

[0006]

[Operation] With the above configuration, the water to be treated is supplied from the water supply pipe to one chamber, the flocculant is added to the water from the flocculant supply pipe, and the water to be treated and the flocculant are added by the underwater stirring blade. Stir to mix. At this time, the water flow generated by the underwater stirring blade circulates through each chamber in the treated water tank, flows parallel to the membrane surface of the membrane module in each chamber, and is separated into solid and liquid through the separation membrane. A shearing force is applied to the adhering cake layer to remove it from the membrane surface. Further, the water flow becomes uniform at each position in the cross section of the flow path, and the membrane surface of the membrane module is uniformly cleaned. Therefore, the water flow generated by the underwater stirring blade for stirring and mixing can be used for cleaning the separation membrane, and there is no need to use additional power for cleaning the membrane surface.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 4, the inside of the treated water tank 1 is divided into a plurality of chambers 3 by a partition wall 2, and each adjacent chamber 3 is opened alternately through an upper opening 4 or a lower opening 5 formed in the partition wall 2. A flow path is formed that communicates with each other and circulates through each chamber 3 in series.

A membrane module 6 is immersed in each chamber 3, and the membrane module 6 is formed by arranging a plurality of membrane elements 7 in parallel inside a framework 8 at an appropriate interval α. The membrane surface of the element 7 is arranged along the flow direction of the water flow (vertical direction in this embodiment). This membrane element 7 is formed by pasting a separation membrane 10 on the front and back sides of a flat filter plate 9 and interposing a gap forming member 11 between the filter plate 9 and the separation membrane 10. A permeate flow path 12 is formed. Furthermore, each membrane element 7
A liquid collection pipe 13 is provided in communication with the permeate flow path 12, and a suction pump 14 is interposed in the middle of the liquid collection pipe 13.

In one room 3 where the membrane module 6 is not placed, an underwater stirring blade 16 connected in conjunction with a drive motor 15 is placed, and a water supply pipe 17 to be treated, a flocculant supply pipe 18 and The pH adjuster supply pipe 19 is open. In addition, the chamber 3 includes a pH meter 20 and a water level meter 2.
1 is provided. Furthermore, a sludge drawing pipe 22 is connected to the chamber 3 at the most downstream position, and a sludge pump 23 is interposed in the sludge drawing pipe 22.

[0010] The operation of the above configuration will be explained below. The water to be treated 24 is supplied from the water to be treated supply pipe 17 to the chamber 3 at the most upstream position, that is, the mixing tank. At this time, the water level is measured by the water level gauge 21 to maintain the water level at which the membrane module 6 is immersed and the water to be treated 24 can flow through the upper opening 4. Then, the flocculant is added to the water to be treated 24 from the flocculant supply pipe 18, and p
After adding the H regulator, the underwater stirring blade 1 is driven by the drive motor 15.
6 is rotated to stir and mix the water to be treated 24 and the flocculant. At this time, the water flow generated by the underwater stirring blade 16 flows into the adjacent chamber 3 through the lower opening 5, and thereafter circulates through each chamber 3 of the treated water tank 1 by overflowing the upper opening 4 and the lower opening 5. do.

[0011] Then, while the water to be treated 24 flows parallel to the membrane surface of the separation membrane 10 of the membrane module 6 in each chamber 3, the suction pump 14 is driven to separate the water to be treated 24 into solid and liquid. At this time, the permeated liquid that has passed through the separation membrane 10 is taken out from the liquid collection tube 13 through the permeated liquid channel 12, and suspended matter adheres to the membrane surface in the form of a cake tank. However, when the water stream flows parallel to the membrane surface, a shearing force is applied to the cake layer and the cake layer is removed from the membrane surface. Further, the water flow becomes uniform at each position in the cross section of the flow path, and the membrane surface of the membrane module 6 is uniformly cleaned. Therefore, the water flow generated by the underwater stirring blade 16 for stirring and mixing is transferred to the separation membrane 1.
0 cleaning, and there is no need to use separate power for cleaning the membrane surface.

The water flow generated by the underwater stirring blades 16 may be either an upward flow or a downward flow.

[0013]

As described above, according to the present invention, the water flow generated by the underwater stirring blade circulates through each chamber in the treated water tank, applies shear force to the cake layer adhering to the membrane surface, and improves the membrane surface. Since the cake layer is removed from the membrane, the water flow generated by the underwater stirring blade for stirring and mixing can be used to clean the separation membrane, and there is no need to use separate power to clean the membrane surface, reducing energy consumption. can be achieved. Further, by forming the mixing tank in one room of the treated water tank, the installation space can be reduced.

[Brief explanation of the drawing]

FIG. 1 is an overall vertical cross-sectional view of a coagulation separation apparatus of the present invention.

FIG. 2 is an overall plan view of the coagulation separation device in the same embodiment.

FIG. 3 is an overall vertical cross-sectional view of the membrane module in the same example.

FIG. 4 is a longitudinal cross-sectional view of the membrane element in the same example.

[Explanation of symbols]

1　　　　　　　　treatment water tank 3 Room 6 Membrane module 16 Underwater stirring blade

Claims (1)

[Claims] Claim 1: A plurality of chambers are formed in the treated water tank, and each adjacent chamber is connected to form a flow path that circulates in series, and one chamber is provided with a water supply pipe and a flocculant supply pipe. A coagulation separation apparatus characterized in that an underwater stirring blade is provided to form a mixing tank, and a membrane module is arranged in another appropriate chamber so that the membrane surface is along the flow direction of the water to be treated.