JPH1043526A - Purifier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To unnecessitate a pump for feeding a filter aid or the like and to provide an inexpensive and small-sized purifier by communicating a porous ceramic filter with a filter aid tank whose space partitioned by a weir opened upward is packed with a filter aid, thereby circulating water. SOLUTION: In a first purifying chamber 14a, a porous ceramic filter 24 and an ultraviolet lamp 26 are arranged. In a second purifying chamber 14b, a weir 32 opened upward and a weir 34 opened downward on the opposite side are arranged, and a space between the weirs 32, 34 is packed with active carbon to form an active carbon bed 28. On the opposite side to a partition 14c of the weir 34, a weir 36 opened upward is provided, and a space between a body 14 and the partition 14c is packed with a filter aid to form a filter aid tank 30. While water is circulated through the passage including the space below the active carbon bed 28 and the ceramic filter 24, the circulating water is supplied from the bottom of the filter aid tank 30 by operating a value 52 to overflow the filter aid, thereby forming the filter aid bed on the surface of the ceramic filter 24. Thus, the ceramic filter 24 is prevented from clogging.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the technical field of a purification device suitably used for a pool or a so-called 24-hour bath.

[0002]

2. Description of the Related Art Due to the recent health boom, people who are familiar with swimming are increasing. In addition, for the purpose of comfortable living to take a bath at any time at home and saving of water and gas,
Time baths are attracting attention, and various types of household bath water purification devices for realizing such baths are being developed, sold, and showing signs of widespread use. Each of these uses a purifying device, supplies water (hot water) from a pool or a bath to the purifying device, and returns purified water to the pool or the like again, that is, circulates and purifies the water, thereby purifying the water. Keeping it clean.

[0003] Such a purifying apparatus basically includes a pre-filter for roughly filtering water to remove hair, dust and the like, a precision filter for highly filtering water to remove red and oil, and the like.
Further, if necessary, a sterilizing means using ultraviolet rays or ozone, an adsorption purifying means for deodorizing or removing organic substances, a heater (heater) for maintaining water at a predetermined temperature, and the like are appropriately combined and configured. I have.

[0004] By the way, the precision filter used in such a purifying device is required to have a high level of performance capable of removing scales, oils and the like from water. As a filter satisfying such requirements, a porous ceramic filter (hereinafter, referred to as a porous ceramic filter)
A ceramic filter) is known. The ceramic filter has fine pores three-dimensionally, and can filter even fine particles such as oil, dirt coming out of the human body, and scales. However, due to the high performance of the ceramic filter, fine pores are likely to be closed by clogs and oils (clogging is likely to occur), and the filter cake is deposited in a short time and the performance is deteriorated. In addition, if the deterioration becomes severe, it may be necessary to replace an expensive ceramic filter.

Therefore, in a purifying apparatus using a ceramic filter, a powdery filter aid such as diatomaceous earth or a fibrous filter aid such as cellulose or pulp fiber is usually provided on the surface of the ceramic filter (the inflow surface of the water to be filtered). Is formed, and filtration with a ceramic filter is performed through the filter aid layer. By having such a filter aid layer, since contaminated water does not flow directly into the ceramic filter, the filter cake does not directly deposit on the surface of the ceramic filter, and the clogging of the ceramic filter is suitably prevented. Can be. Further, in a normal purification device, in order to maintain the filtration performance of the ceramic filter, backwashing in which washing water is vigorously flowed in the opposite direction to the filtration is periodically performed. Since the filter cake and the filter aid layer can be separated from the ceramic filter by washing, the backwash can be performed very efficiently and favorably.

[0006] Such a filter aid layer is formed by preparing a dispersion water in which the filter aid is dispersed in water, filtering the dispersion water through a ceramic filter, and capturing the filter aid on the surface of the ceramic filter. It is formed. Therefore, in the purification device for forming the filter aid layer, the filter aid tank for filling the filter aid, the dispersing device for producing the dispersion water (sometimes the same as the filling tank), and the dispersed water in the purification device. A dedicated device for forming a filter aid tank such as a pump for supply is required, and the increase in size and cost cannot be avoided.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems of the prior art, and to use a ceramic filter capable of performing high-level filtration and form a filter aid layer on the surface thereof to form a water filter. A purifying device used for a pool, a 24-hour bath, or the like, for filtering water, and a dedicated pump for supplying a filter aid into the purifier and a dispersion device for producing a dispersion water in which the filter aid is dispersed. It is an object of the present invention to provide an inexpensive and small-sized purifying apparatus which does not require any other means.

[0008]

In order to achieve the above object, a purifying apparatus according to the present invention comprises a porous ceramic filter for filtering water, and a filter aid in a space partitioned by a weir opening upward. A filter aid tank filled with the porous ceramic filter via the weir and capable of communicating with the porous ceramic filter, and a circulation for circulating water through a path including the portion above the filter aid tank and the porous ceramic filter. And a filter aid discharge line which connects a circulation path of the circulation means and the filter aid tank via at least one valve.

Further, it is preferable that the porous ceramic filter and the filter aid tank are arranged in the same space.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a purifying apparatus of the present invention will be described in detail based on a preferred embodiment shown in the accompanying drawings.

FIG. 1 shows a conceptual diagram of an example of a purifying apparatus 10 (hereinafter referred to as a purifying apparatus 10) of the present invention. The purification device 10 shown in FIG. 1 is a purification device for a pool 12,
Basically, it is configured to have a purifying device main body 14, a heating device 16, and a transfer means 20 for connecting each part of the pool 12 and the purifying device main body 14 by a predetermined route to transfer water.

The purifying device body 14 has, for example, a rectangular parallelepiped external shape, and as shown in FIG. 1, a first purifying chamber 14 which is liquid-tightly separated from each other by a partition wall 14c.
a and the second purification chamber 14b.

In the first purification chamber 14a on the left side of the figure, a porous ceramic filter 24 (hereinafter, ceramic filter 2) is provided.
4) and an ultraviolet lamp 26 serving as a sterilizing means. The porous ceramic filter has three fine holes.
Dimensionally, fine particles such as suspended metal salts, oils, organic matter such as dirt, impurities, bacteria, etc., for example, 0.25 μm
It can be filtered to fine particles of about 1 μm. Therefore, the purification device 10 of the present invention using the ceramic filter 24 can purify water at a very high level.

Since the ceramic filter 24 has high performance, impurities such as red and oil contained in water are apt to block fine pores. As described above, the performance is deteriorated. On the other hand, in the purification device 10 according to the present invention, since a filter aid layer described later is formed on the surface of the ceramic filter 24, the clogging of the ceramic filter 24 itself is extremely small, and the life of the ceramic filter 24 can be extended. It is possible to realize stable performance with a predetermined performance over a long period of time.

In the illustrated purification device 10, the ceramic filter 24 has a cylindrical shape having a through hole at the center, and the upper and lower surfaces of the through hole are the ceiling surface and the floor surface (or a predetermined surface) of the first purification chamber 14a. In a state of being closed by a closing member), it is fixed in the first purification chamber 14a by a known method. In the illustrated example, the water is a ceramic filter 2
By flowing from the outer wall surface of No. 4 so as to reach the through hole, it is highly filtered by the ceramic filter 24, and impurities such as red and oil are removed. Although the illustrated example has a configuration having only one ceramic filter 24, the purification device of the present invention may include a plurality of ceramic filters. In addition to the cylindrical shape, the shape may be a plate shape or the like.

An ultraviolet lamp 26 as a sterilizing means is inserted into a through hole of the ceramic filter 24. The water that has reached the through-hole of the ceramic filter 24 after being filtered is sterilized in this space by the ultraviolet light generated by the ultraviolet lamp 26 and ozone. Although the purification device 10 in the illustrated example generates ultraviolet light and ozone by one ultraviolet lamp 26, the ultraviolet light and ozone may be generated using a dedicated ultraviolet lamp respectively. The ozone generation source is not limited to an ultraviolet lamp, and various known methods can be used. Further, the use of ultraviolet light and ozone as the sterilizing means is not limited, and either one of them may be used as the sterilizing means, or a sterilizing means other than ultraviolet light and ozone may be used.

On the other hand, a second purification chamber 14b on the right side of the purification device main body 14 in the drawing contains an activated carbon layer 2 serving as an adsorption purification means.
8 and a filter aid tank 30 are arranged.

As shown in FIG. 1, the second purifying chamber 14b
, A weir 32 whose upper part is open, and a first purification chamber 1 of the weir 32
4a and a weir 34 which is disposed on the opposite side and which opens downward. In the space formed by the two weirs, a filter material that allows water to pass but does not allow activated carbon to pass through is arranged, and the activated carbon is filled thereon, whereby the activated carbon layer 28 is formed. In addition, as this filter material, it is preferable to use a material through which a filter aid described later cannot pass, such as a nonwoven fabric, a glass filter, or a material in which garnet particles are spread on a stainless steel mesh. The activated carbon layer 28 adsorbs and removes impurities, bacteria, and organic matter (such as dead bacteria) generated by sterilization, which cannot be filtered by the ceramic filter 24.
In addition, the water is deodorized and finally purified water is obtained.

Here, the weir 34 is a weir that opens downward, and the activated carbon layer 28 has the filter material disposed in the space formed by the weir 34.
There is a space below. As will be described in detail later, the water sterilized by the ultraviolet lamp 26 is supplied to the partition wall 14c and the weir 32.
Flows into the second purification chamber 14b from above, flows into the activated carbon layer 28 from above over the weir 32, passes below, and
Finally, the water is returned to the pool 12 as purified water.
Therefore, purified water is always stored in the space below the activated carbon layer 28. In the apparatus of the illustrated example, the water stored in this space is used as washing water for back washing of a ceramic filter 24 and the like described later. This allows
By using water as washing water, contamination inside the apparatus during backwashing can be prevented, and water can be purified to a predetermined state even immediately after backwashing. With this configuration, the purified water for cleaning can be stored in the tank without wasting space in the apparatus.

On the side of the weir 34 opposite to the partition 14c, a weir 36 whose upper side is open is disposed.
(A housing), a filter aid tank 30 filled with the filter aid is formed. As described above, since the ceramic filter 24 has an extremely fine filtration space (hole),
If water is used directly to filter water, these fine pores will be closed, and the processing capacity will gradually decrease, and in severe cases, the expensive ceramic filter 24 will not be renewable. Therefore, a filter aid layer is formed on the surface of the ceramic filter 24, that is, the outer wall surface into which water flows in the illustrated example, and water flows into the ceramic filter 24 through the filter aid layer, whereby the ceramic filter 24 itself is formed. Is prevented from being clogged, and the cleaning effect of the backwashing of the ceramic filter 24 described later is further improved.

As the filter aid, various known materials such as a powdery filter aid such as diatomaceous earth and lime, a fibrous filter aid such as cellulose, pulp fiber and asbestos, and a silica gel capable of selectively removing proteins are used. Available. Also,
A plurality of filter aids may be used, such as a lower layer (formed on the surface of the ceramic filter 24) of the fibrous filter aid and an upper layer of the powdery filter aid. As will be described later in detail, in the purification device 10 of the illustrated example, the water is circulated in a predetermined path including the space below the activated carbon layer 28 and the ceramic filter 24, and the valve 52 is operated from the bottom of the filter aid tank 30 by operating the valve 52. By supplying the circulating water simply or continuously, the filter aid overflows from the weir 36 and is supplied to the space, thereby forming a filter aid layer on the surface of the ceramic filter 24.

The water is transferred to each of these parts by the transfer means 20 and circulated and purified with the pool 12 or used for forming a filter aid layer and backwashing the ceramic filter 24. The pool 12 and the inlet of the pump 18
Connected by an inlet line 38 having a valve 37,
The discharge port of the pump 18 is connected to the outside of the ceramic filter 24 in the first purification chamber 14a by a supply line 42 having a valve 40. Here, in the middle of the inflow line 38, a pre-filter 44 made of sponge, mesh, or the like is used.
Large impurities such as hair and garbage are
Here, it is not removed and does not reach the purification device main body 14.

The through-hole of the ceramic filter 24 communicates with an outflow line 46 having a valve 54 and a valve 48.
Between the partition wall 14c and the weir 32 in the second purification chamber 14b via the valve 50, in the space below the activated carbon layer 28 via the valve 50, and on the bottom of the filter aid layer 30 via the valve 52, respectively. Connected.

As the water is purified, filter cake builds up on the surface of the ceramic filter 24 (filtration aid layer), and the filtration and purification ability is reduced. Therefore, it is necessary to periodically clean the first activated carbon layer 22 and the ceramic filter 24. In the purification device 10 shown in the figure, a backwash line 56 is provided, and a ceramic filter is formed by backwashing using a jet water flow in which cleaning water (in the present invention, purified water in the storage tank portion 56) and air are mixed. 2
4 is performed. In the purification device 10 of the illustrated example, the backwash line 56 is provided between the pump 18 of the supply line 42 and the valve 40 and the ceramic filter 2 of the outflow line 46.
4 and the valve 54 are connected to each other. The jet nozzle 58, the valve 60 on the supply line 42 side from the jet nozzle 58, and the valve 6 on the outflow line 46 side
And 2.

The jet nozzle 58 is a so-called ejector having a nozzle portion whose flow path is rapidly narrowed and an air introduction nozzle at this nozzle portion. The jet nozzle 58 controls the flow rate of the cleaning liquid supplied to the backwash line 56 by the pump 18. The air is rapidly increased in the portion, and air is introduced from the air introduction nozzle by the suction force generated by the speed change and mixed with the cleaning liquid to generate a high-speed jet water flow. In the apparatus shown in the figure, the jet stream is supplied to an outflow line 4.
6, the water is injected into the through-hole of the ceramic filter 24 and flows in a direction opposite to the circulation and purification of water, thereby removing the filter residue attached to the outer wall surface of the ceramic filter 24 together with the filter aid layer, and performing washing. In addition, about this backwashing operation,
Details will be described later. Further, a drain line (blow) 68 having a valve 72 is connected to the outside of the ceramic filter 24 of the first purification chamber 14a for discharging water distribution or the like by backwashing.

As described above, the water passes through the activated carbon layer 28 in the second purification chamber 14b, becomes purified water, and reaches the space below the activated carbon layer 28. This space is the return line 7
8 is connected to the pool 12. Here, a valve 80 is arranged on the return line 78, and the heating device 16 is arranged in parallel with the valve 80.

The heating device 16 includes a control valve 8
2. It is composed of a heat exchanger 84, valves 86 and 74. The control valve 82 branches off the return line 78 on the purification device main body 14 side of the valve 80, and passes through the valve 86, the heat exchanger 84, the valve 88, and the valve. 66
Merges with the return line 78 on the pool 12 side. In the purification device 10 of the illustrated example, the control valve 82
In step 2, the temperature of the water returning to the pool 12 is measured, the amount of water flowing into the heating device 16 and the amount of water traveling in the return line 78 are adjusted, and the water branched and flowing into the heating device 16 is heated by the heat exchanger 84. Then, by joining the return line 78 again, the purified water is set to a predetermined temperature, and the water temperature in the pool 12 is maintained at the predetermined temperature. In the purification device of the present invention, the method of heating water is not limited to this, and various known water temperature adjustment methods such as a method of adjusting the heating temperature in the heat exchanger to maintain the water temperature at a predetermined temperature can be used. is there.

Further, the return line 78 and the inflow line 3
8, the return line 78 and the supply line 72 are connected (bypassed) via a valve 90 and a valve 92, respectively.

The purifying apparatus 10 according to the present invention basically has the above-described structure. Hereinafter, the operation of forming a filter aid layer, purifying water circulation, and backwashing the ceramic filter 24 will be described. .

The formation of the filter aid layer of the ceramic filter 24 is performed as follows. First, valves 90, 4
0, 54 and 50 were opened, and all other valves were closed.
8 → the first purification chamber 14a → the through-hole of the ceramic filter 24 → the lower space. In this state, the valve 52 is opened intermittently a predetermined number of times or continuously for a predetermined time. Thereby, the circulating water flows from the bottom into the filter aid tank 30, and the filter aid tank 30
The filter aid in the inside overflows the weir 36 and the activated carbon layer 2
8 into the lower space. In addition, since the filter aid is overflowed from below by water and overflows to the lower space, and the water is circulated through a path including this space, the filter aid is preferably used for circulating water. Distributed. Further, since the circulating water is always drawn from the return line 78, the filter aid flowing into the lower space of the activated carbon layer 28 does not mix into the activated carbon layer 28, and the activated carbon layer 28 By using a filter material through which a filter aid cannot pass,
Mixing of the filter aid into the activated carbon layer 28 can be more suitably prevented.

Here, in the circulation path, water passes through the ceramic filter 24 in the same manner as in ordinary circulation purification, so that the filter aid mixed and dispersed in the circulating water is removed from the surface (outside) of the ceramic filter 24. (A wall surface) to form a filter aid layer. That is, according to the present invention, in a purifying apparatus for forming a filter aid layer on the surface of a ceramic filter, an inexpensive and small-sized purifier can be provided without the need for a filter for supplying a filter aid or a dispersion apparatus for the filter aid. realizable.

In the purifying apparatus 10 shown in the figure, when the water is circulated and purified (that is, during normal operation), the valves 37 and 37 are used.
40, 54, 48, 80, 86 and 88 are open,
All other valves are closed. Pool 12
The water in the inside of the first purification chamber 14a is supplied to and pumped from the inflow line 38 through the supply line 42 to the outside of the ceramic filter 24 in the first purification chamber 14a by the pump 18, so that the side wall of the ceramic filter 24 extends from the outer wall to the through hole. Go through,
Highly filtered.

Inflow into the through hole of the ceramic filter 24
The filled water is passed through the ultraviolet lamp 2 in this through hole.
6 is sterilized by the ultraviolet light and ozone generated, and is discharged from the outflow line 46 through the valve 48 to the second purification chamber 14b.
Between the partition wall 14c and the weir 32. Partition wall 14
The water flowing between the c and the weir 32 overflows the weir 32 and flows into and passes through the activated carbon layer 28, becomes purified water, flows into the space below the activated carbon layer 28, and is filtered. It is charged into the second purification chamber 14b including the agent tank 30, and flows into the return line 78. In the purified water that has flowed into the return line 78, the amount of water flowing into the heating device 16 is adjusted by the control valve 82 according to the water temperature, and the water heated by the heat exchanger 84 and the unheated water merge. At a predetermined temperature and returned to the pool 12.

Further, backwashing of the first activated carbon layer 22 and the ceramic filter 24 is performed as follows. First, all valves other than the valves 90 and 92 are closed, and the pump 18 is driven to circulate water. When the output of the pump 18 becomes maximum, the valve 92 is closed, and the valves 60 and 64 of the backwash line 56 and the valve 72 of the drain line 68 are opened. As a result, purified water below the activated carbon layer 28 is supplied from the return line 78 to the pump 18.
And flows into the backwash line 56 from the supply line 42 to generate a jet water flow, and the ceramic filter 24
Is injected into the through hole. The jet water jet injected into the through-hole of the ceramic filter 24 passes through the through-hole, and removes the filter cake, which has been deposited on the outer wall surface of the ceramic filter 24 together with the filter aid, and cleans the ceramic filter 24. , Through a drain line 68 in which the valve 72 is opened, and is discharged to the outside as drain water.

FIG. 2 is a schematic view of another example of the purification device of the present invention. The purification device 10 shown in FIG. 1 has a configuration in which the filter aid tank 30 and the space in which the ceramic filter 24 is arranged are completely separated, but the purification device 100 shown in FIG. The tank 30 and the ceramic filter 24 are configured to be arranged in one housing 102, that is, in the same space. In the purification device 100, the water of the pool or bath is supplied to the purification device 100 by the pump 105, purified, and returned to the pool or the like.

Although not shown in FIG.
Needless to say, piping, valves and the like for circulating and purifying the water of the pool or bath are arranged at 0 as required. In addition, the purifying apparatus 100 also has various purifying means such as sterilizing means using ultraviolet rays or ozone, adsorption purifying means using activated carbon or zeolite, a pre-filter, a heating device, a backwashing device, etc., as necessary. Of course, it may be arranged.

In the purifying apparatus 100 shown in FIG.
The housing 102 has a substantially cylindrical shape whose diameter is reduced downward, and inside the housing 102, a weir 104 that is open substantially upward in a plane substantially parallel to the side surface is formed over the entire circumference. A filter aid such as diatomaceous earth, lime, cellulose, and pulp fiber is filled between the weir 104 and the housing 102.
A filter aid tank 30 is provided. On the other hand, a ceramic filter 2 is provided in a space inside the weir 104 (hereinafter, referred to as an internal space).
A plurality of 4 are arranged and held by a known method. The ceramic filter 24 has a cylindrical shape, the upper surface is a closing member 24a, the lower surface is a closing member 24b,
Each is closed.

The internal space in which the ceramic filter 24 is disposed is connected to a discharge port of a pump 105 by a supply line 106 having a valve 108. Further, a filter aid discharge line 110 having a valve 112 is formed so as to branch off from the supply line 106 and communicate with the inside of the filter aid tank 30. The number of the discharge lines 110 may be one or plural, and
What is necessary is just to make it possible to supply the filter aid inside to the internal space without unevenness. On the other hand, an outflow line 114 of the water filtered by the ceramic filter 24 is connected through the closing member 24b on the lower surface of the ceramic filter 24. Outflow line 114 has a valve 116 outside housing 102.
Is arranged. In addition, to drain backwash wastewater,
A drain line 118 having a valve 120 is provided in the internal space.
Is connected.

During normal circulation purification, valves 108 and 1
16 is opened, and the water of the pool or bath is supplied from the supply line 106 to the internal space where the ceramic filter 24 is disposed via the valve 108 by the pump 105. The water supplied (filled) into the internal space flows into the ceramic filter 24 from the outer surface, passes through the side wall, reaches the through-hole, is highly filtered, and is discharged from the outflow line 114 (if necessary, through another purification device). Via) returned to the pool.

During the formation of the filter aid layer, the pump 105 →
Supply line 106 → internal space → ceramic filter 24
→ Outflow line 114 →… →→ Circulates water in the circulation path of pump 105. While performing this circulation, the valve 112 of the discharge line 110 is opened intermittently a predetermined number of times or continuously for a predetermined time. Thereby, the filter aid tank 3
The circulating water flows into the space 0, and the filter aid in the filter aid tank 30 overflows the weir 104, flows into the internal space and is dispersed in the water, and is further dispersed by the circulating water to produce dispersed water. Here, since the circulating water has passed through the ceramic filter 24 as in the case of ordinary purification, the dispersed water is filtered by the ceramic filter 24, and a filter aid is captured on the surface thereof, thereby forming a filter aid layer. Is done.

As in the case of the above-described purifying apparatus 10, the filter aid is overflowed by water and overflowed from below to be supplied to the internal space, and the water is circulated through a path including this space. Therefore, the filter aid is suitably dispersed in the circulating water. If necessary, a check valve may be provided between the filter aid tank 30 and the internal space of the weir 104. Further, a separate pump may be provided to overflow the filter aid.

Although the purification apparatus of the present invention has been described in detail above, the present invention is not limited to the above embodiment, and various improvements and changes may be made without departing from the gist of the present invention. Of course.

[0043]

As described above in detail, according to the present invention, in a purification apparatus for forming a filter aid layer on a surface thereof using a ceramic filter capable of high-level filtration, a filter aid layer is formed. An inexpensive and small-sized purifying apparatus can be realized by eliminating the need for a dedicated pump for use and a dispersion tank for a filter aid.

[Brief description of the drawings]

FIG. 1 is a schematic view of an example of a purification device of the present invention.

FIG. 2 is a schematic view of another example of the purification device of the present invention.

[Explanation of symbols]

10, 100 purification device 12 pool 14 purification device main body 16 heating device 18, 105 pump 20 transfer means 24 (porous) ceramic filter 26 ultraviolet lamp 28 activated carbon layer 30 filter aid tank 32, 34, 36, 104 weir 37, 40 , 48, 50, 52, 54, 60, 62, 7
2,80,86,88,90,92,108,112,
116, 120 Valve 38 Inflow line 42, 106 Supply line 44 Prefilter 46, 114 Outflow line 56 Backwash line 58 Jet nozzle 68, 118 Drainage line 76 Bypass line 78 Return line 82 Control valve 84 Heat exchanger

Claims (2)

[Claims] 1. A filter capable of communicating with said porous ceramic filter through said weir, wherein a filter aid is filled in a space partitioned by a porous ceramic filter for filtering water and a weir whose upper part is open. A circulating means for circulating water through a path including the auxiliary tank and a portion communicating with the upper part of the filter aid tank and the porous ceramic filter; and a circulation path by the circulating means and at least one valve for the filter aid tank. A purifying apparatus, comprising: a filter aid discharge line connected through a filter. 2. The purifying apparatus according to claim 1, wherein the porous ceramic filter and the filter aid tank are arranged in the same space.