JP2006052620A - Minute substance removal device of intake facility - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a minute substance removal device of an intake facility capable of solving such a problem that a grit chamber 20 is installed in the intake institution of the conventional technique, the sand fraction is settled and eliminated, and a screen 16 is installed to eliminate a suspended matter in the intake facility formed in a passage to which the water surface is continued (the water passage becomes the same water surface when the stream stops), accordingly fine suspended solids such as water-bloom and turbid substance can't be eliminated from water intake and that an intake pump and an impeller of an intake pump or a generator is damaged. <P>SOLUTION: A grit chamber 20 is installed in the water passage of the intake facility to which the water surface is continued, and the fine suspended solids can be eliminated from the water intake without impairing such an advantage that there are few pressure losses in the water passage in the conventional technique. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

Detailed Description of the Invention

Technology to which the invention belongs

  The present invention relates to technology for removing fine suspended solids in a water intake facility that takes water from lakes, rivers, and sea areas.

Examples of conventional water intake facilities that take water from lakes, rivers, and sea areas are shown in FIGS. The water intake facility is formed by a flow path in which the water level at the intake point (15) and the water level at the intake port (13) are continuous (a flow path that becomes the same water level when the flow stops).
In a conventional water intake facility, a sand basin (20) is installed in the flow path to remove sediment, and a screen (16) is installed to remove suspended matter. At this time, the intake water level (21) falls below the water level (15) at the intake point by the pressure loss of the screen (16).

Problems to be solved by the invention

  Conventional treatment facilities installed in the flow path of water intake facilities that take water from lakes, rivers, and sea areas are sedimentation treatment by a sand basin (20) or removal treatment by a screen (16), and filtration treatment is used. There is no example. Accordingly, the water flowing out from the intake port (14) contains fine suspended solids (aquatic and turbid components), and there is an obstacle that damages the intake pump and the impeller of the generator.

Means for solving the problem

A filtration basin (20) is installed in the channel of the water intake facility where the water surface is continuous. The particle size of the filter medium (2) used for the filter basin (1) should be 2 mmφ or less with less clogging, and 50 mmφ or less that can remove fine suspended solids from the water taken. The filter layer thickness is 30 mm or more.
In the case of a normal filter basin, the particle size of the filter medium (2) is 0.4 mmφ to 0.6 mmφ. The particle size of the filter medium (2) in the present invention is 2 mmφ to 50 mmφ. In that case, when the filtration speed is 50 to 150 m / day, the pressure loss of the filter basin (1) is 1 to 3 cmAq if there is no clogging of the filter medium (2), and there are few obstacles due to the pressure loss in the flow path. This does not impair the advantage of low pressure loss in the flow path in the prior art.
In consideration of the clogging of the filter medium (2), the filtration method is preferably full-layer filtration. The flow direction may be downflow filtration or upflow filtration.

Embodiments of the Invention

Next, an embodiment of the present invention will be described.
FIG. 2 shows an example in which the water at the water intake point (15) is directly introduced into the filtration basin (1). A sand basin and a screen may be separately installed before the filtration basin (1).
The main structure of the filter basin (1) is a housing (4), a filter medium (2), a water collecting device (3), and other parts may include a trough, a surface washing device, and a backwash device.
A normal flow in the filter basin (1) is shown in FIG. In addition, the inflow direction to the filter basin (1) may be any of D, E, and F in FIG.
The water at the water intake point (15) passes through the filter basin (1) and flows out to the water intake (14). In this case, the intake water level {circle around (13)} is lowered by the amount corresponding to the pressure loss of the filter {circle around (1)}.
The water at the water level {15} at the water intake point flows into the upper part of the filter basin (1), passes through the filter medium (2), and flows out to the water intake (14) through the water collecting device (3). Fine suspension is removed by filtration.
FIG. 3 shows a method of washing the filter basin (1) using the backwash pump (8) when the filter basin (1) is clogged with fine suspended substances. Washing is performed by sucking up washing water with a backwash pump (8).
The flow of washing water is shown in FIG. The washing water flows from the lower part of the filter medium (2) through the water collecting device (3) from the intake water level (13). When the washing water passes through the filter medium (2), fine suspended substances are allowed to flow out and the filter medium (2) can be washed. In addition, you may make water pass through the filter medium (2) by another method.
In the example of FIG. 3, the washing water is sucked up from the surface of the filter medium (2) by the backwash pump (8) through the water collection port (10) and the water absorption pipe (9), so that the washing water is contained in the filter medium (2). Pass through. The washing water is discharged through the drain pipe (11) to the drain trough (12) together with fine suspended substances. The backwash pump (8) is installed on the stand (7). The gantry (7) moves on the rail (5) installed on the filtration basin (1) by wheels (6). The water collecting port (10) suspended from the backwash pump (8) is moved so as to cover the entire surface of the filter medium (2) to wash the filter medium (1) over the entire surface of the filter tank (1).
FIG. 4 shows an example in which a coagulation / mixing basin (19) is installed in front of the filtration basin (1) to increase the effect of removing fine suspended solids in the filtration basin (1). In the agglomeration mixing tank (19), a rapid stirrer (17) is installed, and the flocculant added from the chemical injection facility (18) is rapidly mixed.

The invention's effect

  By installing the filtration basin (20) in the flow path of the water intake facility where the water surface is continuous, the advantage of low pressure loss in the flow path in the prior art is not impaired, and it is finer than the water to be taken in. Suspended matter can be removed. Therefore, the damage which damages an intake pump and the impeller of a generator can be reduced.

  Example plan view of the present invention   Example AA sectional view of the present invention (in the case of filtration)   Example BB sectional view of the present invention (in the case of backwashing)   Example of the present invention (when coagulation mixing pond is provided)   Plan view of the prior art   Cross section of the prior art

Explanation of symbols

  (1) is a filtration pond, (2) is a filter medium, (3) is a water collecting device, (4) is a housing, (5) is a rail, (6) is a wheel, (7) is a stand, and (8) is reverse Wash pump, (9) is water intake pipe, (10) is water collection port, (11) is drainage pipe, (12) is drainage trough, (13) is intake water level, (14) is water intake, and (15) is water intake Water level at intake point, (16) is a screen, (17) is a rapid stirrer, (18) is a chemical injection facility, (19) is an agglomeration mixing basin, (20) is a sand basin, and (21) is a water level at the intake port

Claims (1)

  Intake facility where the water level at the intake point (15) and the water level at the intake port (13) are formed with a continuous channel, and the intake basin with a filtration basin (1) installed in the channel

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