JP3513693B2 - Method of transporting filter media in filtration device using floating media - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a filtration apparatus using a floating filter medium having a specific gravity of less than 1 as a filter medium, and an improvement of a biofilm filtration apparatus. sewage,
It is related to the treatment of sewage such as human waste, food wastewater and household wastewater. 2. Description of the Related Art A filtration apparatus using a floating filter medium is mainly of a fixed bed type. When the filter medium is clogged, the entire tank is stirred by using air and treated water to wash and separate contaminants. The method is adopted. This method is described in Japanese Patent Application No. 9-58.
217 is as described in detail. Other methods include mechanical stirring and transfer type cleaning methods. The mechanical stirring type mechanically generates a water flow instead of stirring the air and the washing water to perform the stirring, so that the power cost is large and it is difficult to increase the size. The transfer type is disclosed in Japanese Patent Application Laid-Open No. 7-80489.
Discloses a washing system disclosed in U.S. Pat. No. 6,098,097, which transfers the media transfer directly from the upper portion to the lower portion by using a suction pressure of a pump, and has a problem in terms of efficiency and reliability.
Furthermore, as a transfer type, there is Japanese Patent Application No. 9-58217,
This is performed by forming a series of transfer lines for transferring the filter medium from the upper part to the lower part, and is performed by the discharge pressure and flow rate of the pump. [0003] Japanese Patent Application No. 9-58217 discloses a transfer type filtration device using a buoyant filter medium.
There are the following problems. 1. The force by which the filter media rises and moves to the upper storage tank depends on the buoyancy and the internal pressure of water, and there is a difference in buoyancy depending on the type of filter media.
It cannot be applied equally to any filter media. 2. Depending on the type of the pollutants, the mixing state, etc., the resistance becomes large, and the speed and amount of ascending to the storage tank fluctuate. An object of the present invention is to solve these problems caused only by self-buoyancy. [0004] In the filtration device according to the present invention, a floating filter medium 2 having a specific gravity smaller than 1 is inserted into a filtration tank 1 to form a filter layer 3, and a cover 16 of the filtration tank is formed as a cone. The filter media is collected in the central part, passes through a storage tank inflow valve 12, a filter medium storage tank 9, a filter medium transfer water pump 4, a filter medium transfer water pipe 5, a transfer water adjustment valve 8, a storage tank inflow adjustment valve 7, an ejector 10, a filter medium transfer valve. 11. In a filtration device for transferring from a storage tank 9 to a lower part of a filtration tank by a filtration medium transfer line formed by a filtration medium transfer pipe 15, the storage tank 9 is installed outside the filtration tank, and a filter medium outflow pipe 12a and a storage tank inflow valve 12 are provided. , A storage tank 9, a filter medium drawing pipe 20, and a filter medium drawing pump 17 to form a filter medium drawing line. The transfer method using the filter medium transfer line is a method filed in Japanese Patent Application No. 9-58217, and the present invention is intended to make the method more reliable. [0005] The apparatus according to the present invention is configured as described above, the floating filter medium 2 in the filter tank 1 is compacted upward by buoyancy, the sewage supplied to it is First, the inorganic coarse polluted solids are separated by filtration in the filter layer 3, the contaminants accumulate in the vicinity of the raw water inflow pipe 14, and the filter layer 3 gradually increases the filtration resistance due to the polluted solids. In response to an operation signal based on a value, a certain pattern of operation is performed. That is, the storage tank inflow valve 12 in the upper part of the cone is opened, the storage water withdrawal valve 18 in the filter medium withdrawal line is opened, the filter medium separation water withdrawal valve 19 is closed, the drawing pump 17 is operated, and the filter medium withdraws through the filter medium outflow pipe 12a. Flows into the storage tank 9. At this time, the filter medium transfer line is stopped, the filter medium transfer valve 11 is closed, the transfer water valve 6 is closed, and the transfer water pump 4 is stopped. The transfer water adjusting valve 8 is always fully opened, and the storage tank inflow adjusting valve 7 is always constantly opened. When the drawing pump 17 is in the operating state, the inside of the storage tank 9 becomes negative pressure, the filter medium in the filter tank is sucked through the filter medium outflow pipe 12a and flows into the storage tank 9, and the filter medium floats in the storage tank, and the polluted water is removed. It is carried out of the system via the drawing tube 20 and the drawing pump 17. The stored water withdrawal valve 18 is closed by a timer,
The separation water withdrawal valve 19 is opened, the storage tank inflow valve 12 is closed, and the withdrawal is stopped. At the same time filter media transfer water pump 4
Is operated, the transfer water valve 6 is opened, and the filter medium transfer valve 11 is opened, and the filter medium in the storage tank is transferred to the filter medium separation tank 23 below the filter tank by the transfer line. Washing of the filter medium is performed by mutual contact between the storage tank and the ejector outlet. FIG. 1 shows an example in which a filter medium outflow pipe 12a is extended obliquely upward, and a storage tank 9 is provided outside the filtration tank. A storage tank 9, a storage tank inflow valve 12, a storage water drawing pipe 20, a storage water drawing valve 18, and a drawing pump 17 are provided to form a filter medium drawing line. At the same time, a filter medium transfer line is formed by the filter medium transfer water pump 4, transfer water valve 6, storage tank inflow adjustment valve 7, transfer water adjustment valve 8, ejector 10, filter medium transfer valve 11, and filter medium transfer pipe 15, and filtration is performed from the storage tank 9. It is transferred to the filter medium separation tank 23 at the bottom of the tank. As described in the embodiment of the present invention, the pump and the valve operate based on an operation command based on a timer or a filtration resistance value, and the basic patterns are shown in the following table. [Table 1] As shown in Table 1, a filter medium extraction line is provided, and the filter medium is forcibly extracted by the suction force of the pump, stored, and then reliably transferred to the lower portion of the filtration tank by the filter medium transfer line. Regarding the location of the storage tank, it is possible to set it apart if the water level is secured. According to the present invention, the floating filter medium can be reliably pulled out and transferred from the upper part of the filtration tank to the lower part. Therefore, the transfer plan can be easily implemented by deciding the amount and frequency of washing of the filter medium according to the purpose of the filtration device, the scale capacity, and the conditions of the pollution load. It is easy to increase the size of the filtration device, requires a filter layer thickness such as a biofilm filtration device, and can be applied to large-scale and large-capacity facilities.It does not require washing water, air, etc., and saves area and energy. Is a contributor.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a cross-sectional view of a downward-flow moving bed filtration device using a floating filter medium. [Description of Signs] 1 is a filter tank 4, a filter medium transfer water pump 6, a transfer water valve 7, a storage tank inflow adjustment valve 8, a transfer water adjustment valve 9, a filter medium storage tank 10, and an ejector 11 The filter medium transfer valve 12, the storage tank inflow valve 12a, the filter medium outflow pipe 15, the filter medium transfer pipe 16, the cover 17, the extraction pump 18, the storage water extraction valve 19, the filter medium separation water extraction valve 20, The storage water drawing pipe 21, the treated water pipe 22, the treated water chamber 23 is a filter medium separation tank

Claims (1)

(57) [Claims 1] A floating filter medium having a specific gravity smaller than 1 is inserted into a filtration tank, and sewage flows into a filter layer formed by the floating filter medium,
Filtered by upward or downward flow, the filter medium rises by buoyancy and reaches the upper part of the filter tank, enters the filter medium storage tank (9) via the storage tank inflow valve (12), and is stored. (4) Filter media transfer water pipe (5), transfer water adjustment valve (8), storage tank inflow adjustment valve (7), ejector (10), filter medium transfer valve (11), filter medium formed by filter medium transfer pipe (15) In a filtration device for transferring a filter medium (2) from a storage tank (9) to a lower part of a filter tank by a transfer line, an upper filter medium outflow pipe (12a) of a filter tank (1) is extended in a lateral direction or an oblique direction. A storage tank inflow valve (12) and a filter medium storage tank (9) are provided at the tip, a storage water drawing pipe (20) is provided at a lower part of the filter medium storage tank (9), and connected to a drawing pump (17).
Form a filter media extraction line and connect to the extraction pump (17).
Therefore, draining the stored water from the lower part of the storage tank (9)
A method of transferring a filter medium in a filtration device, wherein the filter medium is drawn out of the filter tank, and is stored in the storage tank (9). Indication of the case Title of the invention Method of transferring the filter medium of the filtration device using the floating filter medium