KR20140117945A - Dissolved Air Flotation Facility Coupled with Membrane Filtration System - Google Patents

Abstract

The present invention relates to a dissolved air flotation (DAF) water processing apparatus coupled with a membrane, and, more specifically, to a DAF water processing apparatus, which is arranged with an aggregation tub for aggregating particulate matters in water into particulates; a floc formation tub for growing the aggregated particulates into flocs having a fixed size; a contact tub for contacting the flocs with microbubbles formed by supplying dissolved air saturated water from an air saturation device; a DAF tub for floating sludge formed by contacting in the contact tub; and a discharge tub connected to the DAF tub, and wherein the aggregation tub, the floc formation tub, the contact tub, the DAF tub and the discharge tub are arranged side by side, and installed together with the air saturation device for supplying dissolved air. The DAF water processing apparatus comprises vessels installed at a low part within the DAF tub, and having a treated water inlet open/closed by an opening/closing device; immersion type membranes installed within the vessels; a filtered water transport pipe connected toward the outside of the DAF tub from the immersion type membranes and having a suction pump connected with an opening/closing valve on the pipe; and a membrane washing means installed to be connected to the filtered water transport pipe and the immersion type membrane vessels to wash the immersion type membranes. The DAF water processing apparatus coupled with a membrane allows the selective back-washing operation of the immersion type membranes by the vessels, and has an effect of performing continuous operation without shutdown of the DAF water processing apparatus.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a dissolved water flotation system,

The present invention relates to a dissolved pressurized floating (DAF) water treatment apparatus incorporating a membrane, and more particularly, to a device for removing particulate matter in water using a dissolved pressurized floating (DAF) water treatment apparatus including an immersion membrane , A vessel containing the immersion membrane is installed in the lower part of the floating tank (DAF) of the water treatment apparatus to smoothly advance the backwashing of the immersion membrane and to remove the substance which can not be removed by the pressurization (UF / MF) to improve the effluent quality of the filtered water.

Dissolved Air Flotation (DAF), which is used for various water treatments, injects pressurized water in which air is dissolved at high pressure into raw water to be treated, So that the sludge floats on the surface, thereby performing solid-liquid separation. This method is applied for the purpose of water treatment for the production of drinking water, industrial and living wastewater treatment, pretreatment of seawater desalination, precipitation and removal of algae.

Membrane-based water treatment technology is a technique of physically separating solid and liquid, and is a water treatment technique using a pressure difference as a driving force without phase change. It is widely applied in various fields depending on the type and performance of the membrane. Materials larger than the nominal pore size of the membrane can be removed and the low molecular weight particles can be removed by the membrane due to the continuous development and development of the membrane.

Recently, as the price competitiveness of membranes has increased, there has been an increasing interest in water treatment techniques using UF (Ultra Filter) or MF (Micro Filter) capable of filtering particles of 0.01-0.1 μm by pretreatment process of RO (reverse osmosis) membrane (UF or MF) for the pretreatment of these RO or NF (Nanofiltration) processes, and dissolved pressurized floating (DAF) devices for algae and oil.

Related prior arts are disclosed in Korean Patent Laid-Open Patent '' Fusion type water treatment apparatus using immersion type membrane and dissolved air floating method '' described in the patent documents of prior art documents, 'Water clarifying apparatus and implementing method' and 'Integrated dissolved air flotation and immersed membrane filtration apparatus and method for using same '.

In the general case of a treatment device combining a dissolved pressurized flotation (DAF) process with a submerged membrane process, if the raw water and the submerged membrane coexist in the DAF flotation tank and the backwashing of the submerged membrane is carried out, The disturbance of the raw water is caused and the upper sludge layer is broken in the disturbed DAF flotation tank to lower the treatment efficiency of the DAF flotation tank and the DAF operation must be stopped during backwashing.

Korean Patent Registration No. 10-1048623 United States Patent Application Publication No. 2009/0211974 A1 U.S. Published Patent Application 2004/0217058 A1

SUMMARY OF THE INVENTION The present invention has been made in order to solve the problems described above, and it is an object of the present invention to provide an immersion membrane in a lower portion of a dissolved pressurized floating (DAF) tank, vessel to allow the sludge fine particles falling off the membrane to be completely discharged into the sludge discharge channel when the backwashing of the submerged membrane is performed in a vessel to prevent leakage of sludge fine particles in the DAF floating sludge (DAF) water treatment device incorporating a membrane configured to prevent water from leaking out of the water.

Another object of the present invention is to provide a method of operating a dissolved pressurized floating water treatment apparatus capable of continuously operating a dissolved pressurized floating water treatment apparatus by selectively installing a plurality of submerged membranes in the lower portion of the DAF flotation tank, And to provide a pressurized floating (DAF) water treatment device.

In order to accomplish the above object, the present invention provides a water treatment apparatus for a dissolved pressurized floating (DAF) water which comprises a membrane, comprising: a flocculation tank for flocculating particulate matter in water into fine particles; A DAF floating tank for floating the sludge generated by the contact of the contact tank, and a DAF treated water discharge tank connected to the DAF floating tank arranged side by side And a transfer pipe for transferring the air to the air saturator for producing fine bubbles in the contact tank by using water in the discharge tank. The sludge discharge unit is installed on one side of the DAF flotation tank for discharging sludge floating in the DAF flotation tank And a treatment water inlet which is installed in the lower part of the DAF flotation tank and is opened / A vessel; An immersion membrane disposed in the vessel; A filtered water delivery pipe connected to the outside of the DAF flotage tank in the immersion membrane, the suction pump connected with the on-off valve on the pipe; And a membrane cleaning means connected to the filtration water transfer pipe and the immersion membrane vessel for membrane cleaning of the immersion membrane.

The membrane cleaning means may include a reverse osmosis tank, a chemical enhanced backwash (CEB) tank, a cleaning in place (CIP) tank, a backwash piping connecting the respective tanks to the filtrate transfer piping and the immersion membrane vessel, It is preferable to perform the reverse washing or chemical washing for membrane cleaning of the immersion membrane by the supply of reverse water or chemical, including the respective opening and closing valves and the transfer pump provided on each of the backwash pipings.

In addition, the apparatus may further include an air pipe including a nozzle below the immersion membrane in the vessel, and an opening / closing valve and an air blower connected to the air pipe, wherein the supply of air by the air blower Further comprising a backwash water discharge pipe connecting the vessel and the sludge discharge channel and an on-off valve disposed on the backwash water discharge pipe for performing air cleaning for cleaning, To discharge the backwash water discharged by the sludge discharge channel to the sludge discharge channel.

In addition, the apparatus may further include a movable discharge water weir installed to be able to move up and down on the upper part of the partition wall in the discharge tank for controlling the sludge discharge of the DAF flotation tank and the DAF floatation level control according to the flow rate variation of the membrane, Are arranged side by side on a single DAF flotation tank and each of the submerged membranes is connected to the sludge discharge channel and the filtrate transfer piping at the same time so that sequential backwash operation of each submerged membrane can be performed, It is preferable to enable treatment by a pressurized floating water treatment apparatus.

According to the present invention, there is provided a dewatering apparatus for a dewatering and dewatering (DAF) process, comprising a vessel for separating a DAF flotation tank and a dipping membrane, wherein the dewatering membrane comprises a sludge fine particle Is discharged smoothly through the sludge discharge pipe without flowing into the DAF floating tank.

In addition, selective backwash operation of the submerged membrane is possible by the vessel, and continuous operation is possible without stopping the operation of the dissolved pressurized floating (DAF) water treatment system.

In addition, when the RO or NF membrane process is present at the downstream of the dissolved pressurized floating (DAF) water treatment unit with the membranes, the frequency of chemical cleaning is reduced by supplying stable and high-quality influent water by filtration of the membrane, It has the effect of extending the extension and running duration.

Also, there is an effect that backwashing can be performed at the installed position without separating or transferring the immersion membrane by the vessel.

Furthermore, compared with the sand filtration process, which is a conventional pretreatment process, there is an effect of reducing the area occupied by the apparatus and improving the production water quality.

FIG. 1 is a view showing a state of installation of the membrane of the present invention in a dissolved pressurized levitation (DAF) treatment and a membrane filtration operation of a dissolved pressurized floating (DAF)
FIG. 2 is a plan view of a state of installation of a dissolved pressurized levitation (DAF) treatment and a membrane filtration operation of a dissolved pressurized floating (DAF) water treatment apparatus incorporating a membrane according to the present invention
FIG. 3 is a diagram showing the state of installation of the membrane of the present invention in a dissolved pressurized levitation (DAF) treatment of a dissolved pressurized floating (DAF) water treatment apparatus and a membrane backwashing operation
FIG. 4 is a view showing a state of installation of the membrane of a dissolved pressurized levitation (DAF) treatment of a dissolved pressurized floating (DAF) water treatment device incorporating a membrane according to the present invention and CEB operation of the membrane
FIG. 5 is a view showing a state of installation of the membrane of the present invention in a dissolved pressurized levitation (DAF) treatment of a dissolved pressurized floating (DAF) water treatment apparatus combined with a membrane and a CIP operation of the membrane

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, preferred embodiments of a dissolved pressurized floating (DAF) water treatment apparatus incorporating membranes according to the present invention will be described in detail with reference to the accompanying drawings. It is to be understood that the present invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, It is provided to inform.

FIG. 1 shows an installation state diagram of a dissolved pressurized floating (DAF) treatment and a membrane filtration operation of a dissolved pressurized floating (DAF) water treatment apparatus incorporating a membrane according to the present invention.

1, a dissolved pressurized floating (DAF) water treatment apparatus incorporating a membrane according to the present invention comprises a flocculation tank 1, a flocculation tank 2, a contact tank 4, a DAF floating tank 5, A DAF treated water discharge tank 6 is arranged side by side with the air saturation device 3 and a vessel 7 and an immersion membrane 8 are installed in the DAF floating tank 5, A filtered water transfer pipe 9 connected to the immersion membrane 8 and a membrane cleaning means 10 are provided.

The flocculation tank 1, the flocculation tank 2, the air saturation device 3, the contact tank 4 and the DAF treated water discharge tank 6 are basically the same as those used in the water treatment process by the dissolved pressurized floating (DAF) As a configuration, each configuration has the following functions. The flocculating tank 1 agglomerates the particulate matter contained in the raw water to be treated with fine particles and the flocculating tank 2 receives the raw water containing the agglomerated fine particles from the flocculating tank 1, Size flock and the air saturator 3 supplies dissolved air to the contact tank 4. The contact tank 4 receives the raw water containing flocs from the floc forming tank 2, And contacts the micro-bubble generated by the air supplied from the saturation device 3 with the flocs. The DAF flotation tank 5 receives the raw water containing the sludge generated by the contact between the microfibers of the contact tank 4 and the flocs from the contact tank 4 to float the sludge, Overflows the sludge floating in the DAF float tank (5).

(DAF) water treatment device incorporating the membrane of the present invention has a vessel 7, a submerged membrane 8, a filtered water transfer pipe 9, And a membrane cleaning means (10).

The vessel 7 is installed in a lower portion of the DAF flotation tank 5 and is formed with a treated water inlet 7g opened and closed by an opening and closing device 7f, the number of the vessels 7 may be increased.

The immersion membrane 8 is composed of a UF (Ultra Filter) or a MF (Micro Filter) and is installed in a vessel.

The filtered water transfer pipe 9 is connected to the outside of the DAF flotation tank 5 at the upper part of the immersion membrane 8 and is connected to a suction pump for sucking the DAF treated water in the vessel on the filtered water transfer pipe 9. [ (11) is connected together with the on-off valve (11a).

The raw water passing through the flocculation tank 1, the flocculation tank 2 and the contact tank 4 is floated in the DAF flotation tank 5 so that the particulate matters contained in the raw water are floated and treated first, The small particles remaining in the water are introduced into the vessel 7 in which the treatment water inlet 7g is opened together with the DAF treatment water by the suction by the suction pump 11 and are separated by the submerged membrane 8 inside Only the filtered particulate matter is discharged to the outside through the filtrate transfer piping 9.

The membrane cleaning means 10 is provided with a filtration water delivery line 9 and an immersion membrane vessel 7 for membrane cleaning of the submerged membrane 8 in which fine particles adhere to the membrane surface in a sludge- ), And a physical membrane cleaning by reverse osmosis or a chemical membrane cleaning by a chemical enhanced backwash (CEB) or a cleaning in place (CIP) is performed.

The sludge is discharged to the outside through a sludge discharge channel (12) for discharging sludge formed on the DAF float tank (5) by floating on the upper side of one side of the DAF floating tank (5).

A specific example of the membrane cleaning means 10 is provided outside the DAF flotation tank 5, and includes a reverse osmotic water tank 13 for physically cleaning the membrane by supplying reverse osmosis water, a chemical membrane A chemical enhanced backwash (CEB) tank 14, a cleaning in place (CIP) tank 15 for cleaning, the respective tanks 13, 14 and 15, a filtered water transfer pipe 9 and an immersion membrane 17b and 17c provided on the respective backwash piping 16 and the backwash piping 16a and 16b and the CIP piping 16c for connecting the piping 16 and the vessel 7 to each other, There are pumps 186a, 18b and 18c. The backwash piping can be supplied to the vessel 7 by any one of the transfer pumps 186a, 18b and 18c to return water or chemical to the physical or chemical properties of the immersion membrane 8, A chemical film cleaning is performed.

On the other hand, in addition to the membrane cleaning of the immersion membrane 8 by the backwash water or the chemical, the air cleaning by the air blower 19 is performed, An air pipe 20 located below the membrane 8 and connected with a nozzle 20b on a pipe under the immersion membrane 8, an opening / closing valve 20a connected to the air pipe 20 and an air blower 19 so that air is supplied to the immersion membrane 8 through the air pipe 20 and the nozzle 20b by the air blower 19 to induce turbulence to remove the sludge sticking to the surface of the membrane, .

As described above, the physical or chemical membrane cleaning by the membrane cleaning means 10 or the cleaning by the air blower 19 by the vessel 7 separating the DAF floating tank 5 from the submerged membrane 8 It is possible to prevent disturbance of the vicinity of the submerged membrane 8 and the DAF flotation vessel even by air cleaning so that the sludge of the particulate matter separated from the membrane by the membrane cleaning or air cleaning is not lifted from the DAF flotation tank 5, (7).

A reverse water discharge pipe 21 and an on-off valve 21a provided on the reverse water discharge pipe 21 are connected between the vessel 7 and the sludge discharge channel 12, The discharge piping 21 transports the backwash water supplied by the membrane cleaning means 10 in the vessel 7 to the sludge discharge channel 12. The backwash water discharge pipe 21 is connected to the CEB tank 14 which is the membrane cleaning means 10 by another backwash pipe 16c and the on-off valve 17c is provided on the backwash pipe 16c, The submerged membrane 8 is washed with the gunpowder agent of the tank 14.

A discharge water weir 22 which can be moved up and down is provided on the partition wall 6a in the discharge tank of the DAF treated water discharge tank 6 to adjust the level of the DAF floating tank 5 according to the flow rate of the membrane When the DAF sludge is discharged, the discharge water weir (22) is raised so that the sludge floated above the DAF float tank (5) can be overflowed by the water head difference. Between the DAF discharge tank 6 and the air saturation device 3, there is provided a transfer pipe 3b for transferring the DAF treated water to the air saturation device 3 by the transfer pump 3a.

In addition, at the end of the filtered water conveying pipe 9 through which the filtration treated water filtered by the immersion membrane 8 is discharged, a filtered water pipe 23 connected to the water separating tank 14 is installed together with the opening / closing valve 23a , And the filtered water can be transferred to the reverse osmosis water tank (14) through the filtrate water pipe (23).

FIG. 2 is a plan view of the installed state of the dissolved pressurized levitation (DAF) treatment and the membrane filtration operation of the dissolved pressurized levitation (DAF) water treatment apparatus incorporating the membrane according to the present invention.

As shown in Fig. 2, the immersion membranes 8a, 8b, 8c, 8d and 8e, together with the vessels 7a, 7b, 7c, 7d and 7e, The plurality of immersion membranes 8a, 8b, 8c, 8d and 8e installed in the plurality of the plurality of the submerged membranes 8a, 8b, 8c and 8d are arranged in the lower portion of the DAF floating tank 5, 7b and 7c and 7d and 7e and are connected to the respective sludge discharge channels 12 and the filtrate transfer piping 9 at the same time. 8b (8c), 8c (8c), 8d (7c), 7d (7e) and 7d (7e) through which the treated water inlet 7g is opened and closed by the opening and closing device 7f, ) 8d and 8e can be successively operated, so that continuous operation is possible without stopping the DAF process.

FIG. 3 shows an installation state diagram of a dissolved pressurized floating (DAF) treatment and a membrane backwashing operation of a dissolved pressurized floating (DAF) water treatment apparatus incorporating a membrane according to the present invention.

3, the sludge is floated in the DAF flotation tank 5 by the dissolved pressurized flotation (DAF) during the dissolved pressurized flotation (DAF) treatment and the membrane backwashing operation, The backwash water is supplied from the tank 13 to the submerged membrane 8 in the vessel 7 through the backwashing pipe 16a and the filtrate transferring pipe 9 to perform membrane washing of the membrane by backwashing do. The air is also supplied to the immersion membrane 8 through the air pipe 20 and the nozzle 20b by the air blower 19 to perform membrane cleaning by air cleaning. At this time, the supply of the powder medicine by the CEB tank 14 and the CIP tank 15 is stopped by the closing of the opening / closing valves 17b and 17c.

FIG. 4 is a view showing a state of installation of the membrane in a dissolved pressurized levitation (DAF) treatment of a dissolved pressurized floating (DAF) water treatment apparatus incorporating membranes according to the present invention and a membrane during CEB operation.

4, when the dissolved pressurized water (DAF) treatment and the CEB operation of the membrane are performed, the reverse water is discharged from the reverse osmosis water tank 13 through the backwash pipe 16a and the filtered water transfer pipe 9, Is supplied to the immersion membrane (8) in the membrane (7) to perform membrane cleaning of the membrane by backwashing. The air is supplied by the air blower 19 to the immersion membrane 8 through the air pipe 20 and the nozzle 20b to remove the air by washing the air with the chemistry implemented by the supply of the explosive medicine by the CEB tank 14 The cleaning is also carried out in parallel. At this time, the supply of the powder medicine by the CIP tank 15 is stopped by the closing of the opening / closing valve 17c.

FIG. 5 shows an installation state diagram of a dissolved pressurized levitation (DAF) treatment of a dissolved pressurized floating (DAF) water treatment apparatus incorporating a membrane according to the present invention and a CIP operation of the membrane.

5, when the dissolved pressurized floating (DAF) treatment and the CIP operation of the membrane are performed, the chemical is supplied from the CIP tank 15 through the CIP piping 16c to the immersion membrane (not shown) in the vessel 7 8) to perform membrane cleaning of the membrane by chemical cleaning. The air is supplied to the immersion membrane 8 through the air pipe 20 and the nozzle 20b by the air blower 19 to perform the air cleaning.

Although the present invention has been described with reference to the drawings, it is to be understood that the invention is not limited to the disclosed embodiments, It will be understood by those skilled in the art that various changes may be made therein without departing from the spirit and scope of the invention.

1: Coagulation tank 2: Floc forming tank
3: Air saturation device 3a: Feed pump
3b: transfer pipe 3c: fine bubble generating nozzle
4:
5: DAF floating tank 6: DAF treated water discharging tank
6a:
7, 7a, 7b, 7c, 7d, 7e: immersion membrane vessel,
7f: opening and closing device 7g: inlet
8, 8a, 8b, 8c, 8d, 8e: immersion membrane
9: Filtration water transfer pipe 10: Membrane cleaning means
11: Suction pump 11a: Open / close valve
12: Sludge discharge channel 13: Reverse osmosis tank
14: CEB tank 15 CIP tank
16a, 16b: Back-up piping 17a, 17b, 17c:
16c: CIP piping
18a, 18b, 18c: transfer pump 19: air blower
20: air piping 20a: opening / closing valve
20b: Nozzle for air cleaning 21: Reverse water discharge pipe
21a: opening / closing valve 22: weir
23: Filtration water piping 23a: On / off valve

Claims (7)

A flocculating tank for flocculating the particulate matter in the water into fine particles, a flocculating tank for flocculating the flocculated fine particles into a floc of a predetermined size, a contact tank for bringing the flocs into contact with the microfibers produced by the supply of the dissolved air of the air saturator, A DAF flotation tank for flotating the sludge generated by the flotation tank and a discharge tank connected to the DAF flotation tank are arranged side by side with an air saturator for supplying dissolved air,
A vessel installed below the DAF flotation tank and having a treated water inlet opened and closed by an opening and closing device;
An immersion membrane disposed in the vessel;
A filtered water delivery pipe connected to the outside of the DAF flotage tank in the immersion membrane, the suction pump connected with the on-off valve on the pipe; And
Membrane cleaning means connected to the filtrate transfer piping and the immersion membrane vessel for membrane cleaning of the immersion membrane;
(DAF) water treatment device incorporating a membrane. The method according to claim 1,
Further comprising a sludge discharge channel installed on one side of the DAF floating tank to receive sludge floating in the DAF floating tank. 3. The method of claim 2,
The membrane cleaning means includes a reverse osmosis tank, a chemical enhanced backwash (CEB) tank, a cleaning in place (CIP) tank, a backwash piping connecting the respective tanks and the filtrate transfer piping to the immersion membrane, Wherein the membrane is provided with a plurality of open / close valves and a transfer pump, wherein the open / close valves and the chemical pumps are connected to each other via a valve, DAF) water treatment device. The method according to claim 2 or 3,
An air pipe including a nozzle below the immersion membrane in the vessel, and an opening / closing valve and an air blower connected to the air pipe, wherein the air is supplied by the air blower to clean the membrane of the immersion membrane (DAF) water treatment device incorporating a membrane. 5. The method of claim 4,
Further comprising a backwash water discharge pipe connecting between the vessel and the sludge discharge channel and an on-off valve installed on the backwash water discharge pipe, the backwash water discharged by membrane washing of the immersion membrane is discharged to the sludge discharge (DAF) water treatment device incorporating a membrane. 5. The method of claim 4,
Further comprising a movable discharge water weir installed at an upper end of the partition wall of the DAF treated water discharge tank for controlling the sludge discharge of the DAF flotation tank and adjusting the level of the DAF flotation tank according to the flow rate fluctuation of the membrane. (DAF) water treatment device incorporating a pressurized water source. 5. The method of claim 4,
The submerged membranes are arranged side by side in a single DAF flotation tank and each submerged membrane is connected to the sludge discharge channel and the filtrate transfer piping at the same time so that sequential backwash operation of each submerged membrane can be performed (DAF) water treatment device incorporating a membrane, which is capable of continuous treatment by a dissolved pressurized floating water treatment device.

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