KR102315906B1 - Membrane filtration for advanced water treatment device using hydraulic head differential - Google Patents

Abstract

An object of the present invention is to provide a membrane filtration advanced water purification system that does not require a separate pressurization facility by applying the principle of siphon and water head difference.
To this end, in the present invention, a pretreatment tank in which untreated water is collected, a membrane filtration tank positioned to have a head lower than the head in the pretreatment tank, a separation membrane immersed in the inside of the membrane filtration tank, and a water head positioned to be lower than the head in the membrane filtration tank A first siphon communicating with the treated water tank and the untreated water in the pretreatment tank to flow into the membrane filtration tank when reaching a predetermined water level, and the treated water in the membrane filtration tank filtered through the immersion type separation membrane to flow into the treated water tank Disclosed is a membrane filtration advanced water purification apparatus comprising two siphons.

Description

Membrane filtration advanced water purification system using water head difference

The present invention relates to a membrane filtration advanced water purification apparatus applying the principle of a siphon and a water head difference, and more particularly, a water tank installed sequentially with a water head difference and a siphon connecting the tanks It relates to a membrane filtration advanced water purification system capable of smoothly purifying raw water without a separate pressure-feeding facility such as a pump for adjusting the flow and treatment amount of raw water by allowing it to be purified while passing through a nonpressure flow method.

Advanced water treatment facility is a water treatment facility to properly treat various harmful substances that are difficult to meet “drinking water quality standards” because conventional drinking water treatment processes (mixing, coagulation, sedimentation, filtration, and disinfection) do not completely remove ozone. There are a technology using a technology, a technology using an advanced oxidation method, a technology using activated carbon, a technology using a membrane separation function, and the like.

In particular, the membrane filtration technology using the membrane separation function is a high-efficiency water purification technology that is rapidly spreading and spreading recently. It uses a semi-permeable membrane with selective permeability with fine pores as a filter medium to separate and remove impurities in raw water. At the same time, it removes pathogenic microorganisms and has a high recovery rate, so it is spotlighted as a next-generation technology that complements the shortcomings of existing water treatment facilities.

Such membrane filtration technology can be classified according to the material, structure, shape, nominal pore size, water flow method, operation method, filtration method, control method, etc. of the separation membrane.

Among them, classification by operation method includes a pressurized type in which water is put through a separation membrane having a thread-like hollow fiber membrane inside a cylindrical housing and passes while applying pressure to filter out foreign substances or impurities, and a separation membrane having micropores is immersed in an immersion tank. There is an immersion type that filters out foreign substances or impurities in the process of passing water. The pressurization type excludes suspended substances by pressurization by a pump, and there is a limit that a suspended substance exclusion process is required as a pretreatment facility, and the power cost for forced circulation is relatively high. The immersion type excludes suspended substances by suction by the pump, and as the separation membrane is installed in the immersion tank, the effect of water temperature is large.

The conventional submerged membrane filtration advanced water purification system collects incoming raw water into a storage tank, mixes it with a coagulant in the mixing tank, aggregates organic materials including particulate matter contained in the raw water in the coagulation tank, and then aggregates Flocculation-treated water, which has been flocculated in the tank, is introduced into the settling tank to precipitate aggregates or particulate contaminants.

In addition, purified water can be obtained by introducing the precipitation treated water of the settling tank into a separation membrane tank equipped with a separation membrane and filtering it through the separation membrane, and if necessary, advanced treatment of ozone and/or activated carbon treatment can be performed.

However, in such a conventional submerged membrane filtration advanced water purification system, a separator for obtaining treated water and a pump for forcibly generating a pressure (negative pressure) difference to overcome the pressure difference due to contamination are installed, so initial installation and operating costs In addition to this high problem, there is no choice but to limit the installation site (site area).

On the other hand, the hydraulic head is a hydrostatic term that refers to the height of a water column, and is related to the potential energy of water at a high place. According to Bernoulli's principle, the pressure difference (Δp) applied by the water column is expressed as the product of the density of water (ρ), the gravitational acceleration (g), and the head difference (Δh), which is the height difference of the water column. Since the two values are constant, the pressure difference is directly proportional to the head difference. Therefore, in order to obtain the desired pressure, it is enough to make the water level as high as the corresponding head of water. The principle of siphon is also a related concept.

Republic of Korea Patent Publication No. 10-2014-0144933 (2014.12.22) Republic of Korea Patent Publication No. 10-2014-0081552 (2014.07.01) Republic of Korea Patent Publication No. 10-1276499 (2013.06.12) Republic of Korea Patent Publication No. 10-0925680 (2009.11.02) Republic of Korea Patent Publication No. 10-0932154 (2009.12.08) Republic of Korea Patent Publication No. 10-0843656 (June 27, 2008) Republic of Korea Patent Publication No. 10-0791896 (2007.12.28)

Accordingly, the present inventors focus on solving the limitations and problems of the existing technology by comprehensively considering the above-mentioned matters, and purify the raw water without a separate pumping facility such as a pump for controlling the flow of raw water and the amount of treated water. The present invention was created as a result of continuous research by making great efforts to develop a membrane filtration advanced water purification system capable of treating water.

Therefore, the technical problem and object to be solved by the present invention is to generate and process the pressure difference required for separation membrane filtration using the head difference while the raw water flows in a natural flow by the action of the water head difference in the water tanks and the siphon connecting the water tanks. It is to provide a membrane filtration advanced water purification system.

In order to achieve the above-described problems and objects, the first embodiment of the present invention provides a pretreatment tank in which untreated water is collected, a membrane filtration tank positioned to have a head lower than the head in the pretreatment tank, and immersion in the membrane filtration tank a separation membrane, a treatment water tank positioned so as to have a head lower than the head in the membrane filtration tank, and a first siphon communicating with the untreated water in the pretreatment tank to flow into the membrane filtration tank after reaching a predetermined water level. It provides a membrane filtration advanced water purification apparatus comprising a second siphon communicating so that the treated water in the membrane filtration tank flows into the treated water tank.

Accordingly, in the first embodiment of the present invention, since the untreated water and the treated water are flowed in a natural flow manner by the water head difference and the siphon principle, the energy consumption and installation space by a separate pumping facility are reduced, and the installation cost and operation cost are reduced. can do.

And the second embodiment of the present invention includes a pretreatment tank in which untreated water is collected, a casing positioned so that the head is lower than the head in the pretreatment tank, an inlet is formed in the upper portion and an outlet hole is formed in the lower portion, and the casing is provided inside A separation membrane, a treatment tank positioned so as to have a head lower than the head in the casing, a first siphon communicating with the untreated water in the pretreatment tank to flow into the casing at a predetermined level, and treatment in the casing filtered through the separation membrane It provides a membrane filtration advanced water purification apparatus comprising a second siphon communicating so that the water flows into the treatment tank.

Accordingly, the second embodiment of the present invention reduces energy consumption and installation space by a separate pressurization facility and reduces installation and operating costs because untreated water and treated water flow in a natural flow manner by the water head difference and the siphon principle. In addition, it can induce and induce the siphon phenomenon more effectively, so that untreated water can be filtered quickly and easily.

In addition, in the first and second preferred embodiments of the present invention, a first valve for opening/closing and controlling the flow rate of untreated water on the first siphon is provided, and the flow of treated water on the second siphon is provided. A second valve for controlling opening and closing and flow rate may be provided.

In addition, in the first and second preferred embodiments of the present invention, the pretreatment tank may be installed to implement at least one pretreatment process of precipitation, powder activated carbon (PAC) contact, mixing, and agglomeration.

In addition, in the first and second preferred embodiments of the present invention, the pretreatment tank may be provided with a stirrer for growing particles contained in untreated water into flocs of a size capable of filtering and precipitating.

In addition, in the first and second preferred embodiments of the present invention, the separation membrane is a hollow fiber type membrane, a flat sheet type membrane, a tubular type membrane, and a spiral wound membrane. It may be formed of any one separation membrane.

The present invention, equipped with the means and configuration for solving the above technical problems, is a water head truck that does not require a separate power, unlike the conventional method of moving raw water and treated water by artificial and mechanical pressure using a pressure feeding facility such as a pump. And by using the siphon principle to flow raw water and treated water in a natural flow method, energy consumption and installation space (site area) by the pumping facility for controlling the flow and amount of raw water and treated water are minimized, and installation and operation costs are reduced. You can save a lot.

In addition, automation and unmanned systems can be automated and unmanned in places where professional manpower is scarce, such as small-scale water purification plants or village water supply, so that integrated operation and management can be achieved. have.

1 is a block diagram schematically showing a membrane filtration advanced water purification apparatus according to a first embodiment of the present invention.
2 is a block diagram schematically showing a membrane filtration advanced water purification apparatus according to a second embodiment of the present invention.

Hereinafter, an embodiment according to the present invention will be described in more detail with reference to the accompanying drawings.

Prior to this, the following terms are defined in consideration of the functions in the present invention, and it is specified that they should be interpreted as concepts consistent with the technical spirit of the present invention and meanings commonly or commonly recognized in the art.

In addition, if it is determined that a detailed description of a well-known function or configuration related to the present invention may obscure the gist of the present invention, the detailed description thereof will be omitted.

Here, the accompanying drawings are illustrated by exaggerating or simplifying a part for convenience and clarity of explanation and understanding of the configuration and operation of the technology, and reveals that each component does not exactly match the actual size.

In addition, when a part includes a certain component, this means that other components may be further included, rather than excluding other components, unless otherwise stated.

< My One practice Yes >

As shown in FIG. 1, the membrane filtration advanced water purification apparatus according to the first embodiment of the present invention is largely a pretreatment tank 10, a membrane filtration tank 20, a separation membrane 30, a treatment water tank 40, and a first siphon. (50) and is configured to include a second siphon (60).

The pretreatment tank 10 stabilizes the fluctuations in the water level of raw water (untreated water) that is taken in and flows in from the outside such as water wells, and maintains a constant amount of raw water discharge. In order to facilitate and at the same time, the pretreatment process for minimizing the contamination of the separation membrane 30 can be performed smoothly.

And the pretreatment tank 10 is connected to a pipe (not shown) that continuously or intermittently supplies raw water from the outside, and the head (h1) of the untreated water contained therein is higher than the head (h2) in the membrane filtration tank (20). installed high.

On the other hand, the head from the reference plane h = P/r _w (pressure head) + V ² /2 g (velocity head) + Z (position head). where P is the pressure, r _w is the weight of water per volume, g is the gravitational acceleration, and V is the velocity.

And the pretreatment tank 10 is a taste and odor causing (causing) substances (2-MIB, geosmin, etc.), synthetic detergents, phenols, It can also be used as a sedimentation tank or a powder activated carbon (PAC) contact tank to remove trihalomethanes and their precursors, chemicals and other organic materials.

In addition, the pretreatment tank 10 can be used as a mixing tank for generating micro floc by electrical neutralization and adsorption by reacting the contaminants contained in raw water and the injected coagulant in a short time, and also adding the coagulant It can also be used as a coagulation tank that forms large flocs so that colloidal substances that do not precipitate and suspended substances with a slow sedimentation rate can be precipitated well.

In addition, the pretreatment tank 10 may have the purpose and function of improving the flocculation efficiency by adding an alkali agent and a coagulation aid when the turbidity is high, or receiving membrane filtration backwash water or wastewater treated water, as well as raw water (untreated water) Mechanically agitate and mix to make an even and uniform mixture, or to change the electrochemical properties of fine suspended matter in colloidal state to destabilize the rapid mixing and to effectively collide the destabilized particles with each other to grow into flocs of a size that can be filtered and settling. A stirrer may be installed.

The membrane filtration tank 20 is installed such that the head (h2) is lower than the head (h1) in the pretreatment tank (10), and the untreated water discharged from the pretreatment tank (10) is supplied through the first siphon (50) to change the water level is stabilized and the discharge amount is kept constant so that the filtration process through the separation membrane 30 can be smoothly performed.

Here, the membrane filtration tank 20 may be connected to a separate pump (not shown) for backwashing and air washing, and a separate for discharging concentrated water such as sludge (raw water excluded from passing through the separation membrane among untreated water) of the pump (not shown) may be connected.

The separation membrane 30 is made of a unit body in which a large membrane area is compactly integrated, and is installed in a state immersed in the membrane filtration tank 20 to receive untreated water from the pretreatment tank 10 through the first siphon 50 and sieve Filtration is carried out through filtration, adhesion, and trapping by the cake layer.

Here, the separation membrane 30 is a hollow fiber type membrane or a flat type only fluid excluding solid components such as impurities, foreign substances, and sludge by an out-to-in method such as negative pressure or differential pressure. It can be implemented to selectively pass through an immersion type membrane of a sheet type membrane). In addition, various forms such as a tubular type membrane and a spiral wound membrane may be used.

And, as the filtration membrane of the separation membrane 30, an organic microfiltration membrane (MF) made of an organic material such as PVDF or PTFE, which has a nominal pore diameter of 0.01 μm and a recovery rate of 90% or more, or an ultrafiltration membrane made of an organic material such as PVDF having a molecular weight fraction of 1,000 Dalton or more. (UF) structure may be employed, but is not particularly limited thereto, and a known inorganic or organic film material may be used.

For example, inorganic films including ceramic and metal films, polypropylene (PP), polyamide (PA), polyethylene (PE), polyvinylidene difluoride (PVDF), polysulfone (PS), polyacrylonitrile One organic layer selected from the group consisting of (PAN), polytetrafluoroethylene (PTFE), cellulose acetate, polysulfonate, and combinations thereof is possible.

In addition, the separation membrane 30 may adopt a form in which one or a plurality of clusters (cassettes, racks) are arranged in parallel.

In addition, by installing a separate air diffuser in the lower part of the separation membrane 30 to make and disperse air in a bubble state so that aeration is sufficiently performed, suspended particles or microorganisms are fixed to the separation membrane 30 to prevent fouling. It can also prevent and improve filtration performance and efficiency.

The treatment water tank 40 is installed such that the head h3 is lower than the head h2 in the membrane filtration tank 20, and the treated water discharged from the membrane filtration tank 20 is supplied through the second siphon 60 to change the water level It is discharged to a water purification plant (not shown) through a separate transmission and drain pipe while maintaining a constant discharge rate by stabilizing the water.

Here, it is preferable that the water head difference between the pretreatment tank 10 and the membrane filtration tank 20 and the water head difference between the membrane filtration tank 20 and the treatment water tank 40 be at least 1 m or more, respectively.

The first siphon 50 is formed as a communication tube and communicates to flow naturally into the membrane filtration tank 20 by the principle of a siphon when the untreated water in the pretreatment tank 10 reaches a certain level.

That is, the inlet of the upper end of the first siphon 50 is immersed in the untreated water in the pretreatment tank 10, and the outlet at the bottom thereof is installed to be submerged in the untreated water in the membrane filtration tank 20. Atmospheric pressure acts on the surface of the untreated water, and when pressed, the untreated water in the pretreatment tank 10 is pulled up or pulled out in the horizontal direction and discharged, and then flows down to the membrane filtration tank 20 with a low head by gravity.

Here, it is preferable to install the first valve 51 on the first siphon 50 to open and close the flow of untreated water and to control the flow rate.

The second siphon 60 is formed as a communication pipe, and the treated water (raw water that has passed through the separation membrane among the untreated water) in the membrane filtration tank 20 filtered through the separation membrane 30 flows into the treated water tank 40 by the principle of the siphon. Let it flow naturally.

That is, the inlet of the upper end of the second siphon 60 is immersed in the treated water in the membrane filtration tank 20, and the outlet of the lower end is installed to be submerged in the treated water in the treated water tank 40. Atmospheric pressure acts on the surface of the treated water, and when pressed, the treated water in the membrane filtration tank 20 is pulled up or pulled out in the horizontal direction and discharged, and then flows down to the treated water tank 40 with a low head due to gravity.

Here, it is preferable to install the second valve 61 on the second siphon 60 to open/close the flow of treated water and control the flow rate.

In the membrane filtration advanced water purification apparatus according to the first embodiment of the present invention configured as described above, the pretreatment tank 10 is installed such that the water head is higher than the membrane filtration tank 20, and the membrane filtration tank 20 is a treatment water tank 40. It is installed so that the head is higher, and the first siphon 50 communicates with the untreated water in the pretreatment tank 10 to flow into the membrane filtration tank 20, and the second siphon 60 is installed in the membrane filtration tank 20 By communicating the treated water to flow into the treated water tank 40, it is possible to flow the raw water and treated water in a natural flow manner in parallel with the water head difference and the siphon principle, thereby pressure-feeding for adjusting the flow of raw water and treated water and the amount of treated water Since no facilities are required, energy consumption and installation space (site area) can be minimized, and installation and operating costs can be greatly reduced.

< My 2 practice Yes >

Hereinafter, a membrane filtration advanced water purification apparatus according to a second embodiment of the present invention will be described with reference to FIG. 2 .

As shown in Figure 2, the membrane filtration advanced water purification apparatus according to the second embodiment of the present invention is largely a pretreatment tank 10, a casing 21, a separation membrane 31, a treatment water tank 40, a first siphon ( 50) and a second siphon (60).

Here, among the components related to the membrane filtration advanced water purification apparatus according to the second embodiment of the present invention, the components having the same or similar effects as those of the first embodiment are denoted by the same reference numerals, and A repetitive and detailed description will be omitted.

The casing 21 receives the untreated water discharged in a natural flow manner through the head difference and the first siphon 50 from the pretreatment tank 10 , filters it through the separation membrane 30 , and then returns the head to the treatment water tank 40 . It is discharged in a natural flowing manner through the tea and the second siphon (60).

That is, an inlet 22 communicating with the outlet of the lower end of the first siphon 50 is formed at the upper portion of the casing 21 , and the outlet 23 communicating with the inlet of the upper end of the second siphon 60 is formed at the lower portion of the casing 21 . The head (h2) of the untreated water flowing therein is lower than the head (h1) in the pretreatment tank (10) and is positioned so that it is higher than the head (h3) in the treated water tank (40).

The separation membrane 31 is provided in a state accommodated inside the casing 21 and receives untreated water from the pretreatment tank 10 through the first siphon 50 to sieve and attach action and trapping action by the cake layer. filtered through.

Here, the separation membrane 31 is a hollow fiber type or tubular membrane (hollow fiber type) except for solid components such as impurities, foreign substances, and sludge by an out-to-in or internal pressure method such as negative pressure or differential pressure. It can be implemented to selectively pass through a pressurized separator such as a tubular type).

On the other hand, it is preferable that the water head difference between the pretreatment tank 10 and the casing 21 and the water head difference between the casing 21 and the treatment water tank 40 be at least 1 m or more, respectively.

In the membrane filtration advanced water purification apparatus according to the second embodiment of the present invention configured as described above, the pretreatment tank 10 is installed such that the water head is higher than the casing 21 , and the casing 21 has a water head higher than the treatment water tank 40 . is installed so as to be positioned high, and in addition, the first siphon 50 communicates the untreated water in the pretreatment tank 10 to flow into the casing 21 , and the second siphon 60 processes the treated water in the casing 21 . By communicating to flow into the water tank 40, it is possible to flow raw water and treated water in a natural flow manner in parallel with the water head difference and siphon principle. Energy consumption and installation space (site area) can be minimized, and installation and operating costs can be greatly reduced.

In addition, unlike the first embodiment of the method in which the separation membrane 20 is immersed in the membrane filtration tank 20, since it has a structure built into the casing 21, installation is much easier, and the pressure difference between the inlet 22 and the outlet 23 is By inducing and inducing the siphon phenomenon by

On the other hand, the present invention is not limited by the above-described embodiments and the accompanying drawings, and various modifications and applications not illustrated are possible without departing from the technical spirit of the present invention, as well as substitution of components and equivalent others. It is clear to those of ordinary skill in the art that the present invention can be widely applied by changing the embodiment.

Therefore, the contents related to the modification and application of the features of the present invention should be interpreted as being included within the technical spirit and scope of the present invention.

10: pretreatment tank 20: membrane filtration tank
21: casing 22: inlet
23: outlet 30/31: separator
40: treatment tank 50: first siphon
51: first valve 60: second siphon
61: second valve

Claims (12)

delete delete delete delete delete delete Installed to implement at least one pretreatment process of precipitation, powdered activated carbon (PAC) contact, mixing, and agglomeration, untreated water is collected, and particles contained in untreated water are provided with a stirrer that grows into flocs of a size that can be filtered and precipitated pre-treatment tank 10;
a casing 21 positioned so that the head is lower than the head in the pretreatment tank 10, the inlet 22 is formed in the upper part, and the outlet 23 is formed in the lower part;
a separation membrane 31 provided in a state accommodated in the casing 21 and made of a hollow fiber type separation membrane, a plate type separation membrane, a tubular type separation membrane, or a spiral wound type separation membrane;
a treatment water tank 40 positioned such that the head of the separation membrane 31 is lower than the head of the water;
a first siphon (50) which is a communication pipe communicating so that the untreated water in the pretreatment tank (10) reaches a certain level and flows into the casing (21) by a siphon phenomenon; and
A second siphon (60), which is a communication pipe, through which the treated water in the casing (21) filtered through the separation membrane (31) flows into the treated water tank (40) by a siphon phenomenon;
A first valve 51 is provided on the first siphon 50 for opening/closing and controlling the flow of untreated water, and opening/closing and controlling the flow of treated water on the second siphon 60 A second valve 61 is provided,
The water head difference between the pretreatment tank 10 and the casing 21 and the water head difference between the casing 21 and the treatment water tank 40 are respectively installed to achieve at least 1 m or more,
The siphon phenomenon of each of the first siphon 50 and the second siphon 60 is further induced by the pressure difference between the inlet 22 and the outlet 23,
In each of the water head difference between the pre-treatment tank 10 and the casing 21 and the water head difference between the casing 21 and the treatment water tank 40, and the first siphon 50 and the second siphon 60 A further induced siphon phenomenon is paralleled, so that purified water is processed without power,
Membrane filtration advanced water purification system. delete delete delete delete delete

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