JPH0622402Y2 - Filtration device using porous ceramic cylinders - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a filtration device used for continuously performing operations such as sterilization and water purification.

2. Description of the Related Art Since a filtration device using a porous ceramic cylinder has extremely high filtration performance, development of a practical one is progressing in various fields, but currently developed ones have strength, capacity and price. There are many problems regarding such things.

Problems to be Solved by the Invention In a filtration device using a porous ceramic cylinder, as in the case of other filtration devices, it is easy to reduce clogging caused by particles contained in the liquid to be filtered and shorten the time required. There is a problem about how to eliminate it efficiently. The time required to clear the clogged state is the filtration work loss time.
How to shorten it is an important issue related to the structure and capacity of the filtration device.

The present invention is to provide a backwash system capable of eliminating the above clogging state in a short time as a system having a simple structure and capable of being operated under a simple operation at any desired time point. And

Means for Solving the Problems According to the present invention, a body in which a plurality of vertically long porous ceramic cylinders whose both ends are supported by a pair of upper and lower support plates is used as a filter medium for pressure filtration is not used by a pump. It is provided on the circulation channel of the unfiltered liquid that pressurizes and flows the filtered liquid, and it is of a type in which the already filtered liquid filtered by the porous ceramic cylinder is allowed to flow into the filtered liquid collection tank. An on-off valve that closes the flow path to the collection tank during backwashing to shut off the flow of the filtered liquid from the body to the filtrate collection tank, and a compressed air source that opens during the backwashing to lower the body. An on-off valve for communicating compressed air into the body by communicating with, and a flow path switching valve for causing circulation of the unfiltrated liquid in a state of blocking the inflow of the unfiltered liquid into the body are provided, Porous ceramics The backwash of the cylinder is performed in a state in which the on-off valve on the flow path from the body to the filtrate collection tank is closed and the circulation of the unfiltrated liquid blocks the inflow of the unfiltrated liquid into the body. Start by switching the flow path switching valve and opening the on-off valve provided on the flow path between the compressed air source and the body so that compressed air from the compressed air source is supplied to the lower part of the body It is characterized by being done.

Function The porous ceramic cylinder of the filtration device according to the above-mentioned present invention closes the on-off valve provided on the flow path from the body to the filtrate collection tank so as to prevent the already filtered liquid from returning to the body, and to the unfiltered body. In the state where the flow path switching valve is switched so that the inflow of liquid does not occur, the on-off valve provided on the flow path between the lower part of the body and the compressed air source is opened to remove the filtered liquid existing in the body. It is backwashed using. The backwash is caused by the impact thrust exerted by the air on the filtered liquid when the bubbles generated by the compressed air flowing into the lower part of the body float and burst into small bubbles. The backwashing of the ceramic cylinder can be continued while maintaining its effectiveness until there is no prefiltered liquid retained in the body. In the filtration device according to the present invention, the number of elements that need to be added to the filtration system in order to facilitate backwashing of the porous ceramic cylinder used as the filter medium is extremely small.

Assuming that the volume of the body is Q ₁ and the amount of the filtered liquid that is discharged from the body when the backwash is performed during the backwash is Q ₂ , then Q ₂ <Q ₁ . In many cases, the quantity Q ₁ is much smaller than the volume of the filtrate collection tank.

Since the backwashing of the porous ceramic cylinder can be performed at any time with a relatively short time required, the filtration operation proceeds in a manner that can be regarded as almost continuous. In the case of backwashing, the density of the filtered material that has been passed through the wall of the porous ceramic cylinder can be somewhat reduced by the presence of bubbles, but the amount of density reduction is small, and it is released due to the rupture of floating bubbles. The backwash action is performed as expected by receiving a sufficiently large penetrating force by the air.

In the drawings, 1 and 2 are a pair of upper and lower support plates, 3 is a plurality of porous ceramic cylinders whose both ends are supported by these support plates 1 and 4, and 4 is a body surrounding these porous ceramic cylinders 3. . The liquid (existing filtered liquid) filtered by passing the unfiltered liquid from the inner side to the outer side of the cylindrical wall of the porous ceramic cylinder 3 reaches the filtered liquid collection tank 6 through the flow path 5.

An on-off valve 7 is provided on the above-mentioned flow path 5 from the body 4 surrounding the porous ceramic cylinder 3 to the filtrate collection tank 6, and the on-off valve 7 is open during filtration work and closed during backwash work. Be kept in the state of. Reference numeral 8 is an opening / closing valve for introducing compressed air from a compressed air source 9 to the lower portion of the body 4 surrounding the porous ceramic cylinder. The opening / closing valve 8 is connected to the filtrate collection tank 6 from the body 4 surrounding the porous ceramic cylinder 3. The open / close state is opposite to that of the on-off valve 7 provided on the above-mentioned flow path 5.

Reference numeral 10 is a flow path switching valve on the flow path for circulating the unfiltered liquid in a pressurized state by the pump 12,
The open / closed state is controlled by the control device 13 together with 8. To backwash the porous ceramic cylinder 3, the on-off valve 7 is closed and the open-close valve 8 is opened, and the flow path switching valve 10 is operated so that the space inside the porous ceramic cylinder 3 is changed to an empty state. Done by. The open / closed states of the open / close valves 7 and 8 and the flow path switching valve 10 by the control device 13 are summarized as follows. In addition, 14 is a tank of unfiltered liquid.

Effect of the Invention In the present invention, a large number of porous ceramic cylinders whose both ends are supported by a pair of upper and lower support plates are used as a filter medium for pressure filtration, and a filtered liquid receiving body surrounding the large number of porous ceramic cylinders is provided. The backwashing of the filter medium (perforated ceramic cylinder) of the filtration device of the type in which the filtrate that flows out is provided with a filtrate collection tank is optional by using a relatively small amount of the filtrate that is stored in the filtrate receiving body. It brings about the effect that it is carried out promptly at a desired time.

[Brief description of drawings]

 The figure is a schematic diagram showing an example of a filtering device according to the present invention. Explanation of symbols 1, 2 ... Support plates 3 and 4 ... Perforated ceramic cylinder 4 ... Body for receiving filtrate 5 ... Flow path 6 ... Filtrate collection tank 7, 8 ... On-off valve 9 ... Compression Air source 10 ...... Flow path switching valve 12 ...... Pump 13 ...... Control device 14 ...... Unfiltered liquid tank

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B01D 29/37 29/62

Claims (1)

[Scope of utility model registration request] 1. A body in which a plurality of vertically long porous ceramic cylinders, both ends of which are supported by a pair of upper and lower support plates, are used as a filter medium for pressure filtration, and a non-filtrate is pressurized by a pump to flow. It is provided on the circulation channel of the unfiltered liquid, and the filtered liquid filtered by the porous ceramic cylinder is made to flow into the filtered liquid collection tank, and on the flow path from the body to the filtered liquid collection tank. An on-off valve that closes during backwashing to shut off the flow of filtered liquid from the body to the filtrate collection tank, and a lower part of the body that is opened during backwashing to communicate with the compressed air source to supply compressed air. An on-off valve to be introduced into the body, and a flow path switching valve that allows the circulation of the unfiltrated liquid to occur in a state in which the infiltrated liquid is prevented from flowing into the body, are provided for backwashing the porous ceramic cylinder. Filtrate from above body The flow path switching valve is switched so that the on-off valve on the flow path to the collecting tank is closed, and the circulation of the unfiltrated liquid occurs in a state where the flow of the unfiltrated liquid into the body is blocked and blocked. In order to be supplied with compressed air from a compressed air source, the opening and closing valve provided on the flow path between the compressed air source and the body is started to open the porous ceramic cylinder. The filtration device used.