JPH11347316A - Simple water purification apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly economical and simple water purification apparatus requiring only a narrow space to install the whole apparatus body by rationally simplify the tank structure employed for floc precipitation, filtration, or back-washing, which usually needs a wide installation space. SOLUTION: This simple water purification apparatus 1 comprises a floc forming tank 3 for forming flocs in object water subjected to treatment by mixing a flocculant and which comprises inclined plates arranged up and down in a plurality of stages at gaps one another for water flow and so inclined as to be higher in the downstream side in the water flow direction, a floc precipitation part 20a for precipitating and separating flocs 21 in the object water flowing from the floc forming tank 3, and a filtration apparatus 24a installed in the downstream side in the water flow direction in relation to the floc precipitation part 20a for filtering and separating flocs 21 of the object water by a filtration material: and the floc precipitation part 20a and the filtration apparatus 24a are installed in a common floc separation tank 5a. The filtration apparatus 24a is formed in a vertical type cylindrical structure having a vertical route 25 for passing the object water in the inside of the cylindrical structure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water purification apparatus used for purifying river water, pond water and other turbid water.
In particular, the present invention relates to a simple water purification device that requires a small space for the entire device and is highly economical.

[0002]

2. Description of the Related Art Conventionally, as this kind of simple water purifier,
A mixing tank for adding and mixing a flocculant to the water to be treated, a floc forming tank for generating suspended components in the water to be treated as flocs by the action of the flocculant, and a floc sedimentation tank for flocculating and setting the flocs. And a filtration tank for filtering the water to be treated from the floc sedimentation tank, a treated water storage tank for storing the treated water after filtration, and the like, and each of these tanks is independently provided in many cases. The above-mentioned filtration tank is configured to forcibly pass the water to be treated vertically downward from the upper surface of the filter medium filled in the tank, thereby performing filtration.

[0003]

The filter tank used in the conventional simple water purifier has a structure in which the water to be treated is forcibly passed vertically downward from the upper surface of the filter medium, so that the treatment capacity is increased. Therefore, the filtration area corresponding to the upper surface of the filter medium must be large, and the installation space of the filtration tank must be considerably widened. On the other hand, when flocs in the water to be treated gradually accumulate on the upper surface of the filter medium and become clogged, backwashing water is injected upward from the bottom of the filtration tank in order to eliminate clogging of the filter medium. Normally, the backwash water once stored is supplied to the bottom of the filtration tank, so a separate backwash tank for storing the backwash water is required, and the installation space for the backwash tank is also secured. Must.

[0004] The present invention has been made in view of the above-mentioned conventional problems, and rationally simplifies the tank structure used for floc sedimentation, filtration, or backwashing, which originally required a large installation space. Accordingly, it is an object of the present invention to provide a simple water purification device that reduces the required space of the entire device and is economical.

[0005]

In order to achieve the above-mentioned object, a simple water purification apparatus according to the present invention comprises a floc forming tank for forming flocs in water to be treated mixed with a flocculant, and a gap for flowing water. A floc sedimentation section, which is composed of inclined plates that are arranged in a plurality of stages vertically and that are inclined so that the downstream side in the flowing water direction is higher, and that sediments and separates flocs in the water to be treated flowing from the floc forming tank, A filtration device disposed downstream of the flowing water direction to filter and separate the flocs in the water to be treated by a filter medium, wherein the floc sedimentation section and the filtration device are arranged in a common floc separation tank. .

Further, a rib body which is inclined in the left-right direction when viewed from behind is protruded from an upper surface of the inclined plate of the floc settling portion in the above configuration.

[0007] The filter medium of the filtration device in each of the above-described configurations is formed in a vertical cylindrical shape having a vertically-treated water passage in a cylinder, and water to be treated is directed from the outer peripheral surface toward the treated water passage. It is passed and filtered.

Further, in the above structure, a plurality of floc separation tanks are arranged in parallel, and the treated water purified by each floc separation tank is disposed downstream of the plurality of floc separation tanks. A backwashing device that injects treated water from the treated water storage tank into the common treated water storage tank and the treated water passage for each filter medium, and passes the treated water from the treated water passage of the filter medium toward the outer peripheral surface to backwash the filter medium. It is provided with.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram showing a simple water purification device according to one embodiment of the present invention. The simple water purification apparatus 1 shown in FIG. 1 generally includes a mixing tank 2 for adding a coagulant such as polyaluminum chloride or a sulfuric acid band to raw water to be treated and mixing the same, and suspending the water to be treated by the action of the coagulant. A floc forming tank 3 for generating turbid components as flocs, an intermediate tank 4 for distributing water to be treated from the floc forming tanks 3, and three flock separation tanks for separating flocs from the to-be-treated water 5a, 5b, and 5c, and a common treated water storage tank 6 for storing treated water after the purification treatment by the respective floc separation tanks 5a, 5b, and 5c.

Next, details of the simple water purification device 1 will be described in more detail. FIG. 2 is a plan configuration diagram of the simple water purification device, and FIG. 3 is a side configuration diagram showing the inside of the simple water purification device. First, the mixing tank 2 has a treated water supply pipe 7 and a coagulant supply pipe 8 on its side.
Is connected, and a motor 9 for driving the stirring propeller 10 is provided on the upper surface. This mixing tank 2 has a water guide pipe 11 on the bottom.
And is communicated with the floc forming tank 3 on the downstream side. Next, the floc forming tank 3 is filled with the partition plate 16 inserted in the middle.
Are partially defined by. Stirring props 13 and 15 driven by a motor 17 and pulleys 12 and 14 are provided in each compartment tank, respectively. The floc forming tank 3 communicates with the downstream intermediate tank 4 through a water passage hole 18 in the side wall. The intermediate tank 4 is provided with three water inlet doors 19a, 19b, 19c on its downstream side wall so as to be able to open and close the flow path.

The floc separation tanks 5a, 5b, 5c are arranged in parallel in a direction orthogonal to the water flow, corresponding to the position of the water inlet doors 19a, 19b, 19c of the intermediate tank 4. The internal equipment of each of the flock separation tanks 5a, 5b, 5c or the equipment individually connected thereto has the same function for each of the tanks. And the remaining floc separation tank 5b,
Those related to 5c are indicated by the reference numerals in parentheses. The floc separation tanks 5a (5b, 5c) mainly include floc sedimentation sections 20a (20b, 20c) that sediment and separate the floc 21 in the water to be treated introduced from the opening of the water inlet door 19a by its own weight, and follow these. The filtration device 24a (24b, 24c) and the filtration device 24a (24
b, 24c) a spare net body 22a (22b, 22c) provided as a protector at the position immediately before.

The floc settling portion 20a (20b, 2)
0c) is a multi-stage inclined plate 5 that is inclined so that the downstream side in the flowing water direction becomes higher, as shown in FIGS. 4 and 5.
8, 58,... These inclined plates 5
, Are arranged up and down with a gap for flowing water, and the downstream end in the flowing water direction is bent downward. Here, the floc settling portion 20a (20b, 20b)
c) are arranged in two rows in the flowing water direction. On the upper surface of each inclined plate 58, rib bodies 59, 59,. The material of the ribs 59, 59,... Is not particularly limited, but is made of, for example, inexpensive L-shaped steel. These floc sedimentation sections 20 a (20 b, 20 c) sediment and separate the flocs 21 in the water to be treated flowing from the intermediate tank 4.

On the other hand, as shown in FIG.
(24b, 24c) is a floc separation tank 5a (5b, 5c).
c) is disposed at the most downstream side. Filtration device 24a
(24b, 24c) is a small-diameter cylindrical inner peripheral net body 29 (60 mesh S) on a donut disc-shaped bottom plate 27.
US net) and large diameter cylindrical outer peripheral net body 28
(Made of SUS net of 60 mesh) are erected and formed in a double cylindrical shape. A space surrounded by the bottom plate 27, the inner peripheral net body 29, and the outer peripheral net body 28 is a filter medium accommodating space 30. The filter medium storage space 30 is filled with countless small filter media 31, 31,....
The inside of the inner peripheral net body 29 is a treated water passage 25. That is, the filter media 31, 31, ... stored in the filter media storage space 30 have a vertical cylindrical shape. Bottom plate 27
A tapered tube 32 is provided vertically downward at the periphery of the central opening. The tapered tube 32 is connected to the water conduit 26a (26b, 26b).
c) It is fitted in the receiving cylinder part 45 at the tip so that it can be inserted and removed, and is water-sealed by the O-ring 33.

The spare net body 22a (22b, 22c) is formed in a semicircular shape using a SUS net of 80 mesh (hole diameter of about 60 μm).
The small-diameter flock that has passed through 0a (20b, 20c) is captured. The spare net body 22a (22
b, 22c) has a vibrator 23a
(23b, 23c) are attached. Vibrator 23
a (23b, 23c) is a spare net body 22a (22b,
In order to shake off the floc 21 attached to 22c), the floc 21 is appropriately vibrated at an amplitude of 7000 μm and a frequency of 700 Hz.

Further, the floc separation tank 5a (5b, 5c)
Inside, the overflow port 38a (38b, 38
overflow tube 39a (39b, 39c) having c)
Has been deployed. Also, the electric valve 41a (41
b, 41c) and the drain pipe 40a (40b, 40c)
Is connected to a lower portion of the most downstream side wall surface of the floc separation tank 5a (5b, 5c). Each flock separation tank 5a, 5b,
Above these and 5c, a common backwash water reservoir 35 is arranged. The overflow port 36a (36
b, 36c), the backwash water supply pipe 34a (34b, 3).
4c) is provided penetrating the bottom surface of the water tank 35 for backwashing. The lower end of the backwash water supply pipe 34a (34b, 34c) is connected to the treated water passage 25 of the filtration device 24a (24b, 24c). The upper part in the backwash water tank 35 communicates with the treated water storage tank 6 via the overflow pipe 56, and excess treated water in the backwash water tank 35 is returned to the treated water storage tank 6. .

Then, as shown in FIGS. 1 and 2, a water storage box 43a (43b, 43c) is provided in the upper part of the treated water storage tank 6.
Is installed. The bottom of the water storage box 43a (43b, 43c) communicates with the bottom of the filtration device 24a (24b, 24c) by a water conduit 26a (26b, 26c). The overflow nozzles 44a (44b, 44b,
44c) is branched and connected in the middle of the water pipe 26a (26b, 26c). The overflow nozzle 44a (44
b, 44c) causes the treated water from the water conduit 26a (26b, 26c) to overflow when the water discharge door 48a (48b, 48c) is closed.

A water storage box 46a (46b, 46c) is continuously provided on a side wall of the water storage box 43a (43b, 43c).
The water storage box 43a (43b, 43c) and the water storage box 46a (46
b, 46c) are the water holes 50a (50b, 50c), respectively.
c, see FIG. 7).
0a (50b, 50c).
b, 48c). And the water storage box 46a
On the side wall of (46b, 46c), a vertically long water outlet (not shown) is formed having an average width of about 1 cm and a width increasing toward the top. Further, a water level detector 47a (47b, 4c) for detecting clogging of the filtration device 24a (24b, 24c).
7c) is provided above the water storage box 46a (46b, 46c).

A treated water discharge port 49 for letting treated water flow out of the tank is provided on a side wall of the treated water storage tank 6. A pump 52 for supplying treated water at the time of backwashing is provided at a back corner in the treated water storage tank 6, and a discharge side pipe of the pump 52 communicates with the inside of the backwash water storage box 35 as a treated water supply pipe 55. doing. In addition, the area | region of the code | symbol 51 shown with the dashed-dotted line in FIG. 2 is a spare space for drinking water, and a chlorine sterilization processing machine, an activated carbon adsorption processing machine, a drinking water storage tank, etc. can be optionally installed.

Here, the flood doors 48a (48b, 48c).
7 is shown in FIG. The water storage box 43a (43b, 43
Sprockets 62 and 63 are pivotally supported at upper and lower positions of a support plate 61 fixed to c), and a chain 64 is hung between the sprockets 62 and 63. Flood door 48a that opens and closes water holes 50a (50b, 50c)
(48b, 48c) are attached to the chain 64 by the attachment 73 at the upper end. On the other hand, the swing arm 67
Is pivotally supported on a pivot 69 of a support 68 fixed to the water storage box 43a (43b, 43c) so as to be vertically swingable.
And the chain 6 on the diagonal side with the mounting position of the mounting
A mounting tool 65 is fixedly mounted on 4, and one end of a swing arm 67 is pivotally supported on a pivot shaft 66 of the mounting tool 65.

The pivot 69 is inserted into one end of an elongated hole 70 formed on the other end of the swing arm 67.
The overflow port 36a (36
A pin 71 projecting from the outer peripheral surface of (b, 36c) is movably inserted in the hole. Overflow port 36a (36
b, 36c) are vertically slidably supported by slide bearings 72 fixed to the legs of the backwashing water storage box 35. That is, the overflow port 36a (36b, 36c) can be moved by the vertical movement width h in the backwash water storage box 35 by the vertical swing of the swing arm 67.

Incidentally, the water inlet doors 19a to 19a of the intermediate tank 4 described above.
9c is also driven to open and close by the same mechanism as the drive mechanism that opens and closes the flood doors 48a to 48c. In addition, the drain pipes 40a to 40c having the electric valves 41a to 41c and the overflow pipes 39a to 3c described above.
As shown in FIG. 8, 9c is collectively connected to one collecting pipe 42 by pipe connection. The backwashing device 76, whose operation will be described in detail later, is provided with the backwash water supply pipe 34a (34b, 34b).
c), water tank 35 for backwashing, pump 52, treated water supply pipe 5
5 mainly. However, the backwashing device of the present invention is not limited to the above configuration.

Next, the operation of purifying the water to be treated by the simple water purification apparatus 1 having the above-described structure will be described with reference to the drawings.
The mixing tank 2, the floc forming tank 3, the intermediate tank 4, and the floc separating tanks 5 a to 5 c are previously filled with water up to the water level 53 to be treated, and the inlet doors 19 a to 19 c of the intermediate tank 4 and the treated water tank 6. Are set in a state in which the flush doors 48a to 48c are opened. Then, the water to be treated from the water supply pipe 7 is introduced into the mixing tank 2. The water to be treated is a coagulant, a bactericide, and a pH that are injected from the coagulant supply pipe 8.
The mixture is vigorously stirred with a stirrer 10 together with an adjusting agent and the like, and mixed. The sufficiently mixed treated water is supplied to the water pipe 11
To the floc forming tank 3. In the floc forming tank 3, the water to be treated is gently stirred by the stirring propellers 13 and 15, and flocs 21 are formed.

The to-be-processed water formed by the flocs 21 gradually enters the water inlet doors 19a (19b, 19c) from the intermediate tank 4.
And is guided into the floc separation tank 5a (5b, 5c). The water to be treated in the floc separation tank 5a (5b, 5c) has a flow rate of about 2-3 mm / sec.
b, 20c), but also at this time, the flocs 21 continue to flocculate and form a large mass, the specific gravity also increases, and the flocs 21 settle and separate by their own weight.

Flock settling portion 20a (20b, 20c)
Is slowly flowing through the gap for flowing water between the inclined plates 58, 58 (see FIGS. 4 and 5). At that time, due to the presence of the rib body 59, the water to be treated is rectified without generating a stray flow, and further, a gentle vortex as shown by a curved arrow 60 is also generated. As a result, the flocs 21 in the water to be treated stay at the back of the rib body 59 (so-called water back) and gather. The flocks 21, 21 gathered in this way
.. Indicate the ribs 5 when water is drained during backwashing described later.
The water flows down to the bottom of the tank along with the right and left inclinations of 9 and is discharged out of the tank from the drain pipes 40a (40b, 40c). By the way, there has not been a known structure in which the flocs 21 are positively stored on the upper surface of the inclined plate. However, the rib member 59 is provided on the upper surface of the inclined plate 58 as in this example, so that The swirl generated on the back of the water makes it possible to reliably retain the floc 21 at the position and separate it from the water. In this way, the heavier flocks 21 are deposited on the inclined plate 58 while sinking, and the lighter flocks pass through the floc sedimentation portions 20a (20b, 20c) together with the water to be treated.

The floc settling portion 20a (20b, 20c)
The water to be treated that has passed through is supplied to the spare net body 22a (22b, 2b).
While approaching 2c), flocks 21 with increased weight spontaneously settle while gathering flocks. The floc 21 having a larger diameter than the pores of the spare net body 22a (22b, 22c) is formed by the spare net body 22a (22b, 22c).
The to-be-processed water containing the small-diameter floc 21 which has been strained and passed through the pores approaches the filtration device 24a (24b, 24c). In addition, the floc 21 moves obliquely downward while floating in the water until it reaches the filtering device 24a (24b, 24c) from the water inlet door 19a (19b, 19c). At that time, the neighboring flocks 21 are gathered together and gradually become large and clumped to increase the weight, and settle at a sedimentation speed of about 2 mm / sec by their own weight. That is, unlike the conventional structure in which most of the flocs are forcibly settled on the upper surface of the filter medium to cause clogging, many flocs 21 are separated from water in a state close to nature prior to filtration. Therefore, the filtration load on the filtration device 24a (24b, 24c) is reduced, the water purification efficiency is improved, and the load during backwashing is also reduced.

As shown in FIG. 9, the fine floc 21A having passed through the pores of the outer peripheral net body 28, together with the water to be treated, is transferred from the entire outer peripheral surface of the filtration device 24a (24b, 24c) to a cylindrical core. Move in the horizontal direction to filter media 31 and 3
Pass through one space. In this case, the filter medium 31 is made of a spherical material having a particle diameter of about 0.4 to 2 mm and a specific gravity of ≒ 1.0, and is almost floating in water.
Water flow resistance is relatively small. Since the floc 21A has a vortex of water (indicated by a swirl arrow 75) on the back side of the filter medium 31 (downstream in the flowing direction indicated by the arrow 74), the floc 21A accumulates at the location and adheres to the filter medium 31. Thereby, Flock 2
1A is efficiently separated, and the final treated water (purified water) is obtained. The treated water thus obtained is supplied to the water pipe 26a.
(26b, 26c), water storage box 43a (43b, 43)
c), water holes 50a (50b, 50c), water storage box 46a
(46b, 46c) and the water outlet, and is stored in the treated water storage tank 6. The treated water in the treated water storage tank 6 reaches the treated water level 54 and is discharged from the treated water discharge port 49 out of the tank.

Since the filtration device 24a (24b, 24c) is a vertical cylinder type, it is compact when viewed in a plane. Further, since the filtration surface of the filtration device 24a (24b, 24c) is the entire outer peripheral surface, the filtration area can be made wider than that of the conventional device in which the filtration surface is a horizontal surface.

By the way, since a general filtration device is integrated with the whole water purification device, it is not possible to easily remove only the filtration device. On the other hand, in this simple water purification device 1, the filtration device 24a (24b, 24c) can be attached and detached from the entire water purification device with one touch. 24a (24b, 24c) can be easily taken out to the outside and can be easily operated. Further, in a state where the filter medium 31 is stored,
(24b, 24c) can also be extracted.

Next, the backwashing operation of the filtration device by the backwashing device 76 will be described. In this simple water purification device 1, three filtration devices 24a, 24b, and 24c are configured in plurals, and individual floc 21A is accumulated between the filter media 31, 31 during the water purification operation, and the individual clogging becomes remarkable. The backwashing process is started for the filtration device 24a, 24b, or 24c. The backwashing process is performed periodically using a 24-hour timer and when the water level detectors 47a, 47b,
Or 47c, any of the filtration devices 24a, 24
This is performed when a certain amount of clogging is detected in b or 24c. Here, an example in which clogging occurs in the filtration device 24a and backwashing is performed is shown. However, the same applies to the other filtration devices 24b and 24c, and a description thereof will be omitted. First, the water inlet door 19a related to the flock separation tank 5a to be backwashed.
Then, the flush door 48a is closed by the chain drive, and then the electric valve 41a is opened. Then, the water to be treated in the floc separation tank 5a is almost drained through the drain pipe 40a and the collecting pipe 42. At this time, the flocks 21 accumulated on the inclined plate 58 of the floc sedimentation section 20a are also taken out of the tank along with the water. In addition, the opening position of the overflow port 36a is lowered in the backwash water tank 35 with the closing operation of the water discharge door 48a.

Therefore, the electric valve 41a is closed once, and the pump 52 is started. The treated water from the pump 52 is sent from the treated water supply pipe 55 into the backwash water storage box 35, and is injected into the treated water passage 25 of the filtration device 24a through the overflow port 36a and the backwash water supply pipe 34a. You. As a result, the treated water flows radially outward in the filter medium accommodating space 30, backwashes the filter medium 31, and removes the floc 21A attached to the back of the water. The treated water used for backwashing collects in the floc separation tank 5a, and when the water level rises and reaches the backwashing water level 57, it is drained from the overflow port 38a and the overflow pipe 39a to the outside of the tank via the collecting pipe 42. . Finally, the pump 52 is stopped, and the electric valve 41a is again stopped.
Is opened, and the water in the flock separation tank 5a is extracted to complete a series of backwashing operations.

As described above, the plurality of floc separation tanks 5a,
When 5b and 5c are arranged in parallel, the treated water in the treated water storage tank 6 can be continuously used as backwash water for each floc separation tank 5a, 5b, or 5c. That is, instead of using the backwash water once in a separate and independent backwash water tank as in the conventional apparatus and using it, the obtained treated water is separated into other flocs while obtaining the treated water in one of the floc separation tanks. It can be used as it is as backwash water for the tank. Therefore, a separate and independent backwash water tank is not required, and the installation space can be reduced. In addition, filtration device 1
In backwashing the base, not only the treated water already stored in the treated water storage tank 6 but also the treated water being generated by the remaining two units at that time can be used as it is, so that a large amount of treated water is used for backwashing. Can be used. As a result, the flow velocity during the backwash can be increased, and the backwash efficiency increases.

As described above, in this simple water purification apparatus 1, the floc separation tanks 5a, 5b, 5c have a floc increasing function, a floc sedimentation separating function, and a floc filtration separating function, and perform a combined operation related to these functions. It is supposed to do. That is, the sedimentation separation and the filtration separation of the floc 21 can be performed in one tank. Therefore, the entire device becomes compact. Incidentally, the simple water purification device 1 has a processing amount of 500 m ³ / day (plane size: 45
00 mm x 1500 mm in width), which is greater than that of a conventional device (capacity 300 m ³ / day) of the same size scale.

In this embodiment, the flock separation tank is 3
The present invention can be applied to a single floc separation tank in principle, provided that the use of treated water during backwashing is not taken into account.

[0034]

As described above, according to the simple water purification apparatus of the present invention, the floc separation tank has a floc increasing function,
Since it has both the floc sedimentation separation function and the floc filtration separation function, floc sedimentation separation and filtration separation can be performed in one tank. For this reason, the entire apparatus becomes compact as compared with the processing capacity, so that equipment costs and running costs can be reduced.
Therefore, this simple water purification device can be suitably used for, for example, cleaning a pond of a golf course or replacing water in a castle moat.
In an emergency, it can be used for drinking water.

When a rib is protruded from the upper surface of the inclined plate, a gentle vortex flows behind the rib when the water to be treated passes above the rib. Floc accumulates in the water and is surely separated from the water to be treated. Thereby, the filtration load in the subsequent filtration device can also be reduced.

In the case where the filter medium is formed in a vertical cylindrical shape having a vertical treated water passage in the cylinder, and the water to be treated is passed from the outer peripheral surface of the filter medium to the treated water passage to be filtered. Means that the outer peripheral surface of the filter medium corresponds to the filtration surface.
Therefore, in order to increase the processing capacity, the height of the vertical cylindrical filter medium may be increased to increase the filtration area.
That is, the plane space of the filtration device is small.

Further, the backwashing device injects treated water from the treated water storage tank common to the plurality of floc separation tanks into the treated water passage of each filter medium, and passes the treated water from the treated water passage of the filter medium toward the outer peripheral surface. When the filter medium is backwashed, the obtained treated water can be used as it is as backwashing water for another floc separation tank while obtaining treated water in any one of the floc separation tanks. Therefore, there is no need for a separate and independent backwash water tank as in the prior art, and the installation space can be reduced. In addition, not only the treated water already stored in the treated water storage tank but also the treated water that is being generated at that time by the remaining floc separation tank can be used as it is for the backwashing of one filtration device. Can be used.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a simple water purification device according to an embodiment of the present invention.

FIG. 2 is a plan view showing the simplified water purification device.

FIG. 3 is a side view showing the inside of the simple water purification device.

FIG. 4 is an external view of the inclined plate of the floc settling portion viewed obliquely from above and rearward.

FIG. 5 is a sectional view taken along line AA in FIG.

FIG. 6 is a longitudinal sectional view showing a filtration device.

FIG. 7 is a side view showing the opening / closing mechanism of the flood door.

FIG. 8 is a perspective view showing a piping system for backwashing.

FIG. 9 is an explanatory diagram showing a state of flowing water near a filter medium in the filtration device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Simple water purifier 3 Flock formation tank 5a, 5b, 5c Flock separation tank 6 Treated water storage tank 19a, 19b, 19c Water inlet door 20a, 20b, 20c Flock sedimentation part 21, 21A Flock 24a, 24b, 24c Filtration device 25 Processing water passage 28 Outer circumference net body 29 Inner circumference net body 31 Filter media 34a, 34b, 34c Backwash water supply pipe 38a, 38b, 38c Overflow port 39a, 39b, 39c Overflow pipe 40a, 40b, 40c Drain pipe 41a, 41b, 41c Electric valve 42 Collecting pipe 48a, 48b, 48c Flush door 52 Pump 55 Treated water supply pipe 58 Inclined plate 59 Rib body 76 Backwashing device

Claims (4)

[Claims] 1. A floc forming tank for forming flocs in water to be treated mixed with a coagulant, and a plurality of vertically arranged steps separated by a gap for flowing water, and a slope inclined so that the downstream side in the flowing water direction becomes higher. A floc sedimentation section that is composed of plates and segregates and separates the flocs in the water to be treated that flowed in from the floc formation tank, and a filtration device that is disposed downstream of the floc sedimentation section in the flowing water direction and filters and separates the flocs in the water to be treated by a filter medium. Wherein the floc sedimentation section and the filtration device are disposed in a common floc separation tank. 2. The simple water purifier according to claim 1, wherein a rib body inclined in the left-right direction when viewed from behind is protruded from an upper surface of the inclined plate of the floc settling portion. 3. The filter medium of the filtration device is formed in a vertical cylindrical shape having a vertically treated water passage in a tube, and the treated water is passed from the outer peripheral surface toward the treated water passage to be filtered. The simple water purification device according to claim 1 or 2, wherein: 4. A common treated water in which a plurality of floc separation tanks are arranged in parallel, and which is disposed downstream of the plurality of floc separation tanks and stores treated water purified by the respective floc separation tanks. A storage tank and a backwashing device that injects the treated water from the treated water storage tank into the treated water passage of each filter medium, and backwashes the filter medium by passing the treated water from the treated water passage of the filter medium toward the outer peripheral surface. The simple water purifier according to claim 3, wherein