JPS63256101A - Membrane separation treating device - Google Patents

Abstract

PURPOSE:To prevent the deposition of a gel layer on the surface of a membrane, to miniaturize the title device, and to reduce the cost of the device by connecting the liq. concentrate outlet of the membrane separation unit wherein a membrane surface cleaning body is inserted in an internal pressure-type tubular membrane to the suction port of a reciprocating pump, and connecting a check valve to the inlet for a raw liq. to be treated. CONSTITUTION:The compressed air from a compressor 40 is alternately supplied to air chambers 26 on both sides through an air supply pipe 41 and a supply and discharge unit 31 to operate the reciprocating pump 6, and the raw liq. 36 to be treated in a raw liq. tank 37 is sucked into the internal pressure-type tubular membrane 1 and a pump room 27 from a check valve 8. The inside of the membrane 1 and pump room 27 are depressurized, and the membrane surface cleaning body 2 is pressed by the flow of the raw liq. 36, goes up while cleaning the membrane surface, collides against an upper partition plate 11, and stops. When the pump 6 begins to discharge, the check valve 8 is closed, the insides of the pump room 27 and membrane 1 are pressurized, the raw liq. permeates the membrane 1 from the inside to the outside, the membrane surface cleaning body 2 is pressed down by the back flow of the raw liq., and the membrane surface is again cleaned. The liq. concentrate not permeating the membrane is returned to the raw liq. tank 37 from a discharge port 22.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention is applicable to the separation treatment of highly concentrated liquids 2, such as sewage treatment, food concentration treatment, pulp industry wastewater concentration treatment, etc., and the treatment of low concentration liquids 2, such as seawater desalination treatment, sewage secondary treatment, etc. This invention relates to a simple membrane separation treatment device used for advanced treatment of treated water, pure water production, etc.

[Prior art]

Conventionally, the following devices are known as membrane separation processing devices.

(1) As disclosed in Japanese Patent Application Laid-Open No. 55-145507, one cylinder is divided by a partition wall into a piston chamber and a reverse osmosis chamber containing a semipermeable membrane element, and connected to a piston in the piston chamber. A reverse osmosis membrane separation treatment device in which water to be treated is injected and discharged by reciprocating movement of a rod-shaped piston inside a reverse osmosis chamber.

(2) As disclosed in Japanese Patent Application Laid-Open No. 52-156180, a core having a spiral passage and a cushion body on the outer surface is inserted into a reverse osmosis separation tube, Reverse penetration #l! A device configured to remove deposits by changing the direction of flow of a liquid to be treated flowing into a pipe into a forward or reverse direction and moving the core back and forth.

(3) JP-A-61-82808 and JP-A-61
As disclosed in Publication No. 149206, a membrane surface cleaning body is installed low inside an internal pressure type permeable tubular membrane, and the liquid to be treated is allowed to flow back and forth within the tubular membrane without forming a closed circulation circuit. . An apparatus configured to perform permeation treatment while mechanically cleaning the membrane surface by reciprocating the membrane surface cleaning body by this flow.

[Problem that the invention seeks to solve]

1-However, in the case of the device described in (1) above, there are the following problems.

(1) Since the liquid to be treated cannot be caused to flow back and forth along the membrane surface, glue layer deposition is likely to occur.

(2) If the liquid to be treated contains solid matter with a large particle size, it will clog and requires pretreatment, making it impossible to directly permeate highly concentrated raw water.

(3) A Gouster piston is required for each M separation unit, resulting in high costs in large-capacity plants.

(4) Mechanical cleaning of the membrane surface cannot be combined, so the membrane surface is likely to become clogged.

Furthermore, in the case of the device (2) above, there are the following problems.

(1) Since a closed circulation circuit for the water to be treated is required, there is a lot of piping loss, and it is not possible to make the device more compact and cost-effective.

■ Since pressurization and depressurization cannot be applied alternately to the membrane surface, the membrane surface is easily clogged.

Furthermore, among the devices mentioned in (5) above, Japanese Patent Application Laid-Open No. 61-8280
The device shown in Publication No. 8 has the following problems.

(1) Since two reciprocating pumps are required for one membrane separation unit (membrane separation unit), it is difficult to make the device more compact and cost-effective.

(2) Because the inlet of the liquid to be treated and the outlet of the concentrated liquid in the membrane separation unit are located at the same end of the tubular membrane, the concentrated liquid in the membrane separation unit is not completely replaced, and the concentration inside the unit gradually increases. Franz may accumulate.

Furthermore, among the devices mentioned in (5) above, JP-A-61-1
In the case of the device based on Publication No. 49206, it is necessary to provide large pressure vessels at both ends of the tubular membrane, so there is a problem that the device cannot be made compact and cost-effective.

[Purpose and structure of the invention]

The object of the present invention is to solve the problems of each of the conventional devices, and particularly to provide a membrane separation treatment device that is an improvement over the device disclosed in Japanese Patent Application Laid-Open No. 61-82808. The gist of the present invention is that a membrane surface cleaning body 2 that is pressed and moved by the flow of the stock solution to be treated is fitted into an internal pressure type tubular membrane 1, and the internal pressure type tubular membrane 1 is housed in a casing filter. A membrane separation unit 4 with a cleaning body is constructed, and a concentrated liquid outlet 5 in the membrane separation unit 4 with a cleaning body is connected to a suction port of a reciprocating pump 6 having no suction valve. The membrane separation processing apparatus is characterized in that a check valve 8 is connected to an inlet 7 of a raw liquid to be processed in a separation unit 4.

〔Example〕

Next, the present invention will be explained in detail using illustrated examples.

FIGS. 1 and 2 show a first embodiment of the present invention, in which a vertical outer shell 10 having a permeate outlet 9 on the lower side of the peripheral wall has an upper end and a lower end. The upper partition plate 11 and the lower partition plate 12 are brought into contact with each other, and each upper partition plate 11. A plurality of vertical internal pressure type tubular membranes 1 having liquid permeability are arranged between the lower partition plate 12, and a membrane surface cleaning body 2 which is pressed and moved by the flow of the raw solution to be treated is inside the internal pressure type tubular membranes 1. The upper partition plate 1 is slidably fitted into the upper partition plate 1.
The seal ring 15 and the end of the internal pressure type tubular membrane 1 are sequentially fitted into the recesses provided in the upper partition plate 1 and the lower partition plate 12, and the upper partition plate 11 has a hole 14 having a smaller diameter than the inner diameter of the internal pressure type tubular membrane 1. is provided so as to communicate with the inside of the internal pressure type tubular membrane 1, and the membrane surface cleaning body 2 is further provided with a through hole 15 that penetrates in the vertical direction.

A lower cover 16 having an inlet 7 for the raw solution to be treated is brought into contact with the lower surface of the lower partition plate 12, and the upper partition plate 1
An upper cover 17 equipped with a concentrate outlet 5 is brought into contact with the upper surface of the outer shell 10, and the peripheral flanges at both ends of the outer shell 10 and each of the partition plates 11, 12 and valley covers 16, 17 are connected by a number of bolts. A casing filter is constituted by the casing filter, an internal pressure type tubular membrane 1 accommodated therein, and a membrane surface cleaning body 2 fitted into the internal pressure type tubular membrane 1.
The membrane separation unit 4 is constituted by these.

The concentrate outlet 5 of the membrane separation unit 4 is connected to the suction port 19 provided at the bottom of the left and right sides of the pump house song 18, respectively.
A check valve consisting of a valve seat 20 and a check valve body 21 disposed above the valve seat 20 is provided at the upper part of both the left and right sides of the Bonguno Usong 18. A discharge port 22 is provided at the outlet.

A rubber diaphragm 24 and the center portion of an outer piston 25 are fixed to both ends of a moving shaft 230 extending in the left-right direction, and the peripheral portion of the diaphragm 24 is fixed to the pump housing song 18. An air supply/exhaust unit is provided with an air chamber 26 and a pump chamber 27 on both the left and right sides, and further includes an air switching valve 50 with an air discharge port 28 and an air supply port 29 between the left and right air chambers 26. The air supply/exhaust unit 51 is connected to each air chamber 26, and compressed air is alternately supplied from the supply/exhaust unit 51 into each air chamber 26, and the air to which compressed air is not supplied is By evacuating the chamber 26 and moving each diaphragm 24 and each outer piston 25 alternately in the left and right direction, the pumping action is performed alternately on both the left and right sides, and the supply/exhaust unit filter 1 and the pump The parts housed in the housing 18 constitute a reciprocating pump 6, and the reciprocating pump 6 is not provided with a suction valve.

A flow rate regulating valve 5 is provided at the discharge port 22 of the pump housing song 18.
2, a check valve 8 is connected to the inlet 7 of the raw liquid to be treated in the membrane separation unit 4, and a permeate take-out pipe having a flow rate adjustment valve 34 is connected to the permeate take-out port 9. 35 is connected, and the inlet 7 of the stock solution to be processed, the check valve 8, and the discharge end of the discharge pipe 55 in the membrane separation unit 4 are arranged in the stock solution to be processed 56 in the stock solution tank 57 containing the stock solution to be processed 56. In addition, the discharge end of the permeate extraction pipe 55 is accommodated in the permeate tank filter 9 that accommodates the permeate 38 .

The air supply port of the compressor 40 and the air supply port 29 of the air switching valve 50 are connected via an air supply pipe 41, and the air supply pipe 41 has an air control valve 42 and a pressure regulation valve 45. A device 44 is provided, and the suction end of a suction pipe 46 of a pump 45 for transporting permeate is arranged in the lower part of the permeate tank filter 9 .

Next, the operation of the membrane separation treatment apparatus of the first embodiment will be explained.

The compressor 40 is operated to supply compressed air to the air supply pipe 41.
By alternately supplying air to the left and right air chambers 26 via the air supply and exhaust unit 51, when the left and right pump parts of the reciprocating pump O are operated, the raw liquid filter 6 to be treated in the raw liquid tank filter 7 is prevented from returning. The liquid is sucked in through the valve 8 and flows upward within the internal pressure type tubular membrane 1, and the pressure inside the internal pressure type tubular membrane 1 and the pump chamber 27 is reduced, and the raw solution to be treated is filled therein.

In this process, the membrane surface cleaning body 2 is pressed by the flow of the raw solution to be treated 3B and moves upward toward the outlet side of the internal pressure type tubular membrane 1 while cleaning the membrane surface of the internal pressure type tubular membrane 1, and then moves upward to the outlet side of the internal pressure type tubular membrane 1. It hits the plate 11 and stops. After the membrane surface cleaning body 2 has stopped, the raw liquid to be treated filtrate 6 is sucked into the pump chamber 27 through the through hole 15 of the membrane surface cleaning body 2 until the suction process of the pump is completed.O Reciprocating pump 6 When the liquid enters the discharge process, the check valve 8 automatically closes and the inside of the pump chamber 27 and the internal pressure type tubular membrane 1 are pressurized, so that the raw liquid to be treated is discharged from the inside of the internal pressure type tubular membrane 1 to the outside. The membrane surface cleaning body 2 is pushed down and moved toward the inlet side of the internal pressure type tubular membrane 1 due to the backflow of the raw solution to be treated, and the membrane surface of the internal pressure type tubular membrane 1 is Washed again.

The raw solution to be treated that does not permeate from the inside to the outside of the internal pressure type tubular membrane 1 becomes a concentrated liquid and passes through the valve seat 20 of the reciprocating pump 6.
The liquid then flows into the stock solution tank 57 through the discharge valve consisting of the check valve body 21, the discharge port 22, and the discharge pipe filter 5. Further, the permeated liquid that has permeated the outside of the internal pressure type tubular membrane 1 flows into the permeated liquid tank 59 through the permeated liquid extraction pipe 55 .

The discharge amount of the reciprocating pump B is adjusted by adjusting the compressed air flow rate adjustment valve 42, and by adjusting the flow rate adjustment valve 42, the output amount of the outer piston 2 is adjusted.
5 is adjusted, and the flow rate of the raw solution to be treated in the internal pressure type tubular membrane 1 and the moving speed of the membrane surface cleaning body 2 are set to appropriate values.

Further, by adjusting the pressure regulating valve 46, the pressure during permeation within the internal pressure type tubular membrane 1 is set to an appropriate value.

The reduced pressure in the suction process in the internal pressure type tubular membrane 1 is set by appropriately setting the diameter of the check valve 8 and the diameter of the through hole 15 of the membrane surface cleaning body 2. Furthermore, the ratio between the amount of liquid that permeates through the internal pressure type tubular membrane 1 and the amount that flows out of the pump as a concentrated liquid is set to an appropriate ratio by adjusting the flow rate regulating valve 2 of the discharge pipe 55.

In addition, in the suction process of the reciprocating bonder 6, the amount of backflow liquid when backwashing with permeated liquid by reducing the pressure inside the internal pressure type tubular membrane 1 can be controlled by adjusting the flow rate adjustment valve 54 of the permeated liquid extraction pipe 35. is set to an appropriate value.

FIG. 5 shows a second embodiment in which the present invention is applied to wastewater treatment in a building, in which a branch pipe 49 having a switching valve 48 is connected to a main sewage pipe 47 in a pill led to the public sewer system. The drainage end of the branch pipe 49 is disposed within the stock solution tank 5Z, and the switching valve 48 is half-opened to supply an appropriate amount of the stock solution 56 from the branch pipe 49 into the stock solution tank filter 7.

A check valve 8 is connected to the inlet 7 of the raw liquid to be treated in the plurality of membrane separation units 4 configured in the same manner as in the first embodiment, and the inlet 7 of the raw liquid to be treated and the check valve 8 are connected to the raw liquid tank 5.
The concentrate outlets 5 of the membrane separation unit 4 are all interconnected and connected to the suction port 19 of a reciprocating bonder 6 without a suction valve, Further, one end of a discharge pipe 35 having a flow rate adjustment valve 32 is connected to the discharge port 22 of the reciprocating pump B.
The other end of the discharge pipe 63 is connected to the main sewer pipe 47.

A permeate extraction pipe 55 equipped with a flow rate regulating valve 4 is connected to the permeate extraction port 9 in each membrane separation unit 4, and the discharge end of the permeate extraction pipe 55 is arranged in the permeate tank 39, And the reciprocating type? A piston 50 in the pump 6 is reciprocated by an electric motor 51 via a rotation reciprocating conversion mechanism 52.

A chemical liquid injection pump 55 is disposed in a chemical liquid tank 54 that accommodates a cleaning chemical liquid 5 filter, and a portion between the discharge port of the pump 55 and the flow rate adjustment valve 54 and the permeated liquid extraction port 9 in the permeated liquid extraction pipe 55. The pump chamber 27 of the reciprocating pumper 6 and the chemical tank 54 are connected via a conduit 58 having a gate valve 57.

The second embodiment is also operated in the same manner as the first embodiment. In the case of the second embodiment, chemical cleaning can also be used. When performing chemical cleaning, stop the operation of the reciprocating bonder 6, close the flow rate adjustment valves 2 and 34, and open the gate valve 57, and turn on the chemical injection pump 5.
5 is operated, and the cleaning chemical solution 55 in the chemical solution tank 54 is passed through the permeate extraction pipe filter 5.5. Membrane separation unit 4. Pump chamber 27 and H I
The internal pressure type tubular membrane 1 is cleaned by circulating through the F path 58.

When carrying out this invention, the internal pressure type tubular membrane 1 having liquid permeability is made of a material with high wear resistance.

Preferably, for example, a ceramic membrane is used, and preferably a tubular membrane having a uniform cross-sectional shape over its entire length. Further, any of an ultrafiltration membrane, a reverse osmosis membrane, and a microfiltration membrane may be used.

Materials constituting the membrane surface cleaning body 2 include sponge,
A comb, metal, ceramic, etc. may be used as a single material or a composite material, and the shape of the membrane surface cleaning body 2 may be any shape as long as there is a gap through which liquid can flow.
Cylindrical body 9 The cylindrical body has an external shape that fits into the cross-sectional shape of the internal pressure type tubular membrane 1. When using a hard material such as metal or ceramic for the membrane surface cleaning body 2, it is preferable that it be manufactured with high dimensional accuracy and that the weight of the membrane surface cleaning body 2 has a specific gravity close to the specific gravity of the undiluted solution to be treated.

In each of the above embodiments, the lower part of the membrane separation unit 4 connected to the check valve 8 is immersed in the raw liquid to be treated 3B in the raw liquid tank filter 7, so that the membrane separation treatment apparatus can be made smaller and more compact.・It can be manufactured in bulk at low cost, and the membrane separation processing equipment can be easily transported and relocated. Also, the pressure of the raw solution to be processed.

The flow rate, the stroke of the reciprocating pump 6, etc. can be easily adjusted, and the internal pressure type tubular membrane 1 can be replaced depending on the properties and concentration of the raw solution to be treated, making it possible to apply the membrane separation treatment device. The range can be widened.

〔Effect of the invention〕

According to this invention, the membrane surface cleaning body 2 that is pressed and moved by the flow of the raw solution to be treated is fitted in the internal pressure type tubular membrane 1, and the internal pressure type tubular membrane 1 is housed in the casing 5 and cleaned. A membrane separation unit 4 with a cleaning body is configured, and a concentrate outlet 5 of the membrane separation unit 4 with a cleaning body is connected to a suction port of a reciprocating bonder 6 that is not equipped with a suction valve, and the membrane separation unit with a cleaning body Since the check valve 8 is connected to the inlet 7 of the raw solution to be treated at 4, the membrane surface of the internal pressure type tubular membrane 1 is constantly subjected to mechanical cleaning by reciprocating movement of the membrane surface cleaning body 2 and internal pressure type tubular membrane cleaning. Backwashing by adjusting the pressure inside the membrane 1,
The permeation separation process can be performed while changing the flow direction, which prevents the formation of a r layer on the membrane surface.
As a result, the amount of permeated liquid per membrane area can be increased to improve membrane separation processing efficiency, and permeation can be performed at a low average flow rate, reducing energy consumption and operating costs. Can be cheaper.

Furthermore, the structure is simple, there are few troubles, and maintenance is easy. In addition, mechanical cleaning and backwashing can be performed regularly with the membrane surface cleaning body 2 without using any special accessory equipment, so even high concentration stock solutions can be permeated and separated without pretreatment. In addition, since there is no need to provide large pressure vessels before and after the membrane separation unit 4, the membrane separation treatment device can be manufactured in a small size and at low cost, and the piping length in the membrane separation treatment device can be minimized. Since it can be made short, it is possible to obtain effects such as reducing pipe flow resistance and reducing operating costs.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view showing a membrane separation processing apparatus according to a first embodiment of the present invention, and FIG. 2 is an enlarged longitudinal sectional side view showing a part of FIG. 1. FIG. 5 is a schematic longitudinal sectional side view showing a membrane separation processing apparatus according to a second embodiment of the present invention. In the figure, 1 is an internal pressure type tubular membrane, 2 is a membrane surface washer, a filter casing, 4 is a membrane separation unit, 5 is a concentrate outlet, and 6 is a membrane separation unit.
is a reciprocating pump, 7 is an inlet of the raw liquid to be treated, 8 is a check valve,
9 is a permeated liquid outlet, 10 is an outer shell, 11 is an upper partition plate, 1
2 is a lower partition plate, 14 is a hole, 15 is a through hole, 16 is a lower cover, 17 is an upper cover, 19 is a suction port, 20 is a valve seat,
21 is a check valve body, 22 is a discharge port, 2'5 is a moving shaft, 24
is a diaphragm, 25 is an outer piston, 26 is an air chamber, 27 is a pump chamber, 28 is an air discharge port, filter 0 is an air switching valve, 61 is a supply/exhaust unit, 52 is a flow rate adjustment valve, 55
5 is a discharge pipe, 54 is a flow rate adjustment valve, filtration 5 is a permeate extraction pipe, 5
6 is the raw liquid to be treated, 57 is the raw liquid tank, 38 is the permeated liquid, filtration 9 is the permeated liquid tank, 40 is the compressor, 41 is the air supply pipe, 4
2 is a flow rate adjustment valve, 45 is a pressure adjustment valve, 45 is a permeate transport pump, 47 is a main sewage pipe, 48 is a switching valve, 49 is a branch pipe, 50 is a piston, 55 is a cleaning chemical solution, 54 is a chemical tank, Reference numeral 55 denotes a pump for injecting a chemical liquid, 56 a liquid injection pipe, and 57 a gate valve.

Claims (1)

[Claims] A membrane surface cleaning body 2 that is pressed and moved by the flow of the raw solution to be treated is fitted into an internal pressure type tubular membrane 1, and the internal pressure type tubular membrane 1 is housed in a casing 3 to form a membrane separation unit 4 with a cleaning body.
The membrane separation unit 4 with a cleaning body has a concentrate outlet 5 and a reciprocating pump 6 without a suction valve.
A membrane separation treatment apparatus characterized in that a check valve 8 is connected to an inlet 7 of the raw liquid to be treated in the membrane separation unit 4 with a cleaning body.