JP6280791B2 - Method for preventing floating of filler, method for starting up water treatment device, water treatment device and septic tank - Google Patents

Description

  The present invention relates to a method for preventing the floating of a filler, a method for starting up a water treatment device, a water treatment device, and a septic tank.

  In a water treatment apparatus such as a septic tank, generally, a filler such as a fluid carrier or a filter medium is used to decompose and remove organic substances in water. However, since the filler is usually manufactured from a synthetic resin and has high water repellency, bubbles easily adhere to the surface and float on the water surface in the initial stage of use. Therefore, the problem is that the filler floats on the water surface during the trial operation of the water treatment apparatus, and it is impossible to confirm the floating and settling in water, which is the original performance of the filler.

  As a method for solving this problem, in Patent Document 1, a surfactant having a defoaming action is used to reduce the initial water repellency of the plastic carrier, that is, the adhesion of bubbles, and to easily exhibit the floating property in water from the initial stage of use. A method is disclosed.

JP-A-10-156378

In the method of Patent Document 1, a nonionic surfactant having a polyoxyalkylene group is used as a surfactant having an antifoaming action. Among them, for reducing the initial water repellency of a plastic carrier, Although effective, the duration of the effect is short, and there are those in which bubbles adhere to the plastic carrier and re-float on the water surface. Therefore, the fluidity of the plastic carrier may not be sufficiently confirmed during the trial operation of the water treatment device.
Moreover, in the method of patent document 1, since surfactant is used in high concentration, there exists a possibility that the initial growth of microorganisms may be inhibited.
The present invention has been made in view of such circumstances, and it is possible to prevent the bubble from adhering to the filler for a long period of time without significantly impairing the initial growth of microorganisms. It aims at providing the raising method, a water treatment apparatus, and a septic tank.

As a result of intensive studies to solve the above problems, the present inventors have found that the antifoaming agent having a cloud point of not more than a specific temperature can suppress the adhesion of bubbles to the filler for a long time even at a low concentration. The headline and the present invention were conceived.
That is, the present invention has the following configuration.

The characteristic configuration of the method for preventing the floating of the filler according to the present invention is that the synthetic resin filler is brought into contact with an antifoaming agent having a cloud point of 8 ° C. or less in a water tank into which water is introduced .

  According to this configuration, when the synthetic resin filler is brought into contact with the antifoaming agent having a cloud point of 8 ° C. or less, the bubbles attached to the filler are broken, and the bubbles do not accumulate around the filler. Thereby, the wettability of the filler surface is improved and the floating of the filler is prevented.

  A further characteristic configuration of the method for preventing the floating of the filler according to the present invention is that the cloud point of the antifoaming agent is 4 ° C. or less.

  According to this configuration, the floating of the filler can be prevented for a longer time.

  The further characteristic constitution of the method for preventing the floating of the filler according to the present invention is that the antifoaming agent contains a compound having a polyoxyalkylene group.

  According to this configuration, the floating of the filler can be prevented for a longer time.

  A further characteristic constitution of the method for preventing the floating of the filler according to the present invention is that the antifoaming agent has a freezing point of 5 ° C. or less.

  According to this configuration, the floating of the filler can be prevented for a longer time. Moreover, even if the temperature at the time of use is low, since the antifoaming agent has fluidity without solidifying, the contact efficiency with the filler does not decrease.

  A further characteristic configuration of the method for preventing the floating of the filler according to the present invention is that water is further introduced into a water tank in which the filler and the antifoaming agent are introduced.

  According to this configuration, by adding the filler and the antifoaming agent to the water tank and then adding water, the antifoaming agent and the filler are mixed when water is added, so that the defoaming agent and the filler are more reliably Can be contacted.

  A further characteristic configuration of the method for preventing the floating of the filler according to the present invention is that the concentration of the antifoaming agent becomes 0.010 to 2.9 g / L when the water is introduced to a predetermined water level in the water tank. is there.

  According to this structure, an antifoamer and a filler can be made to contact more reliably. Moreover, the load to the initial growth of the microorganisms adhering to the surface of the filler can be suppressed by reducing the concentration of the antifoaming agent in this way.

  A characteristic configuration of the method for starting up the water treatment apparatus according to the present invention is that it includes the method for preventing the filler from floating.

  According to this configuration, it is possible to easily start up the water treatment apparatus by suppressing the floating of the filler to the water surface. The start-up of a water treatment device refers to the period from the start of the water treatment device operation until the steady operation when the filler is replenished or replaced during new installation, periodic inspection, repair, etc. A period.

  The characteristic structure of the water treatment apparatus according to the present invention is that it comprises a water tank filled with a synthetic resin filler and an antifoaming agent having a cloud point of 8 ° C. or lower.

  According to this configuration, when the filler in the water tank of the water treatment device and the antifoaming agent having a cloud point of 8 ° C. or lower are in contact with each other, bubbles adhering to the filler are broken, and bubbles are formed around the filler. It will not accumulate. Thereby, the floating of the filler in the water tank of the water treatment apparatus is prevented.

  A further characteristic configuration of the water treatment apparatus according to the present invention is that the defoaming agent has a cloud point of 4 ° C. or less and is charged into the water tank at the time of factory shipment.

  According to this configuration, when the filler and the antifoaming agent having a cloud point of 4 ° C. or lower are in contact with each other, the filler can be prevented from rising for a longer time. In addition, by introducing an antifoaming agent into the water tank at the time of factory shipment of the water treatment apparatus, it is possible to save time and labor for adding the antifoaming agent at the site.

  A further characteristic configuration of the water treatment apparatus according to the present invention is that the concentration of the antifoaming agent becomes 0.010 to 2.9 g / L when water is introduced into a predetermined water level of the water tank.

  According to this structure, an antifoamer and a filler can be made to contact more reliably. Moreover, since the load to the initial growth of the microorganisms adhering to the surface of the filler can be suppressed by reducing the concentration of the antifoaming agent in this manner, the water treatment apparatus can be easily started up.

  A further characteristic configuration of the water treatment apparatus according to the present invention is that the antifoaming agent contains a compound having a polyoxyalkylene group.

  According to this configuration, the floating of the filler can be prevented for a longer time.

  The characteristic structure of the septic tank by this invention exists in the point provided with the said water treatment apparatus.

  According to this configuration, it is possible to provide a septic tank in which the filler hardly floats and can be easily started up.

  As described above, according to the present invention, the water repellency of the filler can be lowered for a long period of time by bringing the antifoaming agent having a cloud point of 8 ° C. or less into contact with the filler. Sometimes the fluidity and sedimentation of the filler in water can be fully confirmed. In addition, an antifoaming agent having a cloud point of 8 ° C. or less can sufficiently exhibit the effect of lowering the water repellency even at a low concentration, so that it does not greatly impair the initial growth of microorganisms. The effect of promoting the initial growth of microorganisms can be expected by precipitating the material in water at an early stage.

It is a graph which shows the relationship between a cloud point and an effect duration. It is an enlarged view of the graph of FIG. 1, and has shown the result to effect duration 2000 minutes.

The cloud point of the antifoaming agent is a temperature at which the aqueous solution starts to become cloudy when the aqueous solution containing the antifoaming agent is heated. When the antifoaming agent exceeds the cloud point, it becomes difficult to dissolve in water and emulsifies and disperses. In this emulsified dispersion state, the effect of the antifoaming agent is maximized.
The cloud point is measured by adjusting an aqueous solution containing 1% by mass of defoaming agent with ion-exchanged water or an aqueous solution containing 10% by mass of antifoaming agent with 25% by mass diethylene glycol monobutyl ether aqueous solution, and then heating the aqueous solution. This is done by visually measuring the temperature at which the aqueous solution begins to become cloudy. When the temperature at which turbidity starts is 20 ° C. or lower, the measurement result with ion-exchanged water is used as the clouding point, and when it is 20 to 90 ° C., the measurement result with 25% by mass diethylene glycol monobutyl ether aqueous solution is used as the cloud point.
Regarding the measurement result with ion-exchanged water, since the water freezes at a temperature of 0 ° C. or lower and the cloud point cannot be measured, the cloud point when clouded at 0 ° C. is set to 0 ° C. or lower.

The cloud point of the antifoaming agent is not particularly limited as long as it is 8 ° C. or lower. However, it is preferably 4 ° C. or lower, more preferably 2 ° C. or lower, more preferably, from the viewpoint of excellent effect of suppressing bubble adhesion to the filler. Is 0 ° C. or lower. The cloud point of the defoamer is preferably low, and the lower limit is not particularly limited.
For the same reason, the freezing point of the antifoaming agent is preferably 5 ° C. or lower, more preferably 0 ° C. or lower, and further preferably −10 ° C. or lower. The freezing point of the antifoaming agent is preferably −20 ° C. or higher.

  The antifoaming agent only needs to exhibit an effect of breaking bubbles adhering to the surface of the filler and suppressing the bubble adhering to the filler. Even those that are not in circulation can be used.

  The antifoaming agent preferably contains a compound having a polyoxyalkylene group (hereinafter also referred to as a polyoxyalkylene compound). 1 type may be sufficient as the polyoxyalkylene type compound which an antifoamer contains, and 2 or more types may be sufficient as it. The antifoaming agent may contain other components in addition to the polyoxyalkylene compound.

  Examples of the polyoxyalkylene group that the polyoxyalkylene compound has include a polyoxyethylene group, a polyoxypropylene group, and a polyoxybutylene group. The polyoxyalkylene group possessed by the polyoxyalkylene compound may be one type or two or more types. The polyoxyalkylene compound having two or more kinds of polyoxyalkylene groups may be a random polymer or a block polymer.

Preferable examples of the polyoxyalkylene compound include compounds represented by the following formula (I).
A-O- (RO) m-B (I)
(In formula (I), R represents an alkylene group, A and B represent hydrogen, an alkyl group, or an acyl group, m represents an integer of 2 to 100. A and B may be the same. And may be different.)

  The alkylene group represented by R is preferably an alkylene group having 2 to 4 carbon atoms, and specific examples thereof include an ethylene group, a propylene group, a trimethylene group, and a tetramethylene group.

  The alkyl group represented by A and B is preferably an alkyl group having 1 to 18 carbon atoms. Specific examples thereof include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. Group, cyclopentyl group, cyclohexyl group, cyclooctyl group, tetradecyl group, octadecyl group and the like.

  The acyl group represented by A and B is preferably an acyl group having 2 to 15 carbon atoms, and specific examples thereof include an acetyl group, a propionyl group, an acryloyl group, a methacryloyl group, an octanoyl group, and a benzoyl group.

  m represents an integer of 2 to 100, preferably 2 to 60, more preferably an integer of 2 to 40.

  In the formula (I), it is preferable that at least one of A and B is an alkyl group or an acyl group, and is an acyl group, from the viewpoint of preventing bubbles from adhering to the filler and being excellent in the anti-floating effect of the filler. Is more preferable. That is, the polyoxyalkylene compound is preferably a polyalkylene glycol derivative (polyoxyalkylene derivative), and is preferably a polyalkylene glycol ether (polyoxyalkylene ether) or a polyalkylene glycol ester (polyoxyalkylene ester). More preferred is a polyalkylene glycol ester.

  Fatty acid esters can also be suitably used as antifoaming agents. The fatty acid ester is preferably a polyhydric alcohol fatty acid ester, more preferably a glycerin fatty acid ester, a sucrose fatty acid ester, or a sorbitan fatty acid ester, and even more preferably a sorbitan fatty acid ester.

  Fillers are used for immobilizing microorganisms and removing sludge in water treatment equipment such as septic tanks. Depending on their use, fluid carriers that place emphasis on buoyancy (specific gravity: about 1), sedimentation-oriented matters. Although there exists a filtration carrier (specific gravity: about 1.1), the present invention is effective in any case.

  Although it does not specifically limit as a synthetic resin which is a material of a filler, For example, polyethylene, a polypropylene, a polystyrene etc. are mentioned. Further, the shape of the filler is not particularly limited.

In the present invention, after the antifoaming agent is introduced into the water tank in which the filler is introduced, water is further introduced into the water tank to perform water treatment (operation). At this time, since the filler and the antifoaming agent are in contact with each other, the bubbles adhering to the surface of the filler are broken and the bubbles are prevented from adhering to the filler, so that the floating of the filler can be prevented.
Note that it is preferable that the antifoaming agent is introduced before water is added to the water tank. Moreover, after making a filler and an antifoamer contact outside a water tank, you may throw these into a water tank.

  When water is filled in a predetermined water level of the water tank in which the filler is charged (when water is charged), the defoamer concentration is preferably 0.010 to 2.9 g / L. More preferably, it is 1.5 g / L, and even more preferably 0.010 to 0.5 g / L. In the present invention, since an antifoaming agent having a cloud point of 8 ° C. or lower is used, even at such a low concentration, it is possible to prevent bubbles from adhering to the filler and prevent the filler from rising. .

  In addition, when water is thrown into the predetermined water level of the water tank, it means a state where the operation can be started after water is poured into the water tank containing the filler and the antifoaming agent. In this state, the sewage to be treated is not put into the water tank.

  The method for preventing floating of the filler according to the present invention can be applied to various water treatment apparatuses including a water tank filled with the filler, and is particularly suitable for a septic tank.

  Since the antifoaming agent has low biodegradability, it can be shipped in advance in a water tank of a water treatment apparatus. Thereby, while reducing a user's work burden, the mistake of an addition amount can be prevented. Of course, the present invention is not limited to this, and it is also possible to ship the antifoaming agent separately from the water treatment apparatus and put it in use.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

The chemicals used in the examples and comparative examples are collectively described below.
KZ-5: 5-person septic tank manufactured by Kubota Corporation NKL-5450: Disarm (registered trademark) NKL-5450 manufactured by NOF Corporation
EMF-607: Disarm (registered trademark) EMF-607 manufactured by NOF Corporation
FDS-2224: Disarm (registered trademark) FDS-2224 manufactured by NOF Corporation
CA-104C: Disarm (registered trademark) CA-104C manufactured by NOF Corporation
CC-118: Disarm (registered trademark) CC-118 manufactured by NOF Corporation
FD-2: Disarm (registered trademark) FD-2 manufactured by NOF Corporation
CA-123: Dishome (registered trademark) CA-123 manufactured by NOF Corporation
CC-438: Disarm (registered trademark) CC-438 manufactured by NOF Corporation
CC-218: Disarm (registered trademark) CC-218 manufactured by NOF Corporation
2309-FZ: New Call 2309-FZ manufactured by Nippon Emulsion Co., Ltd.
PPG-700: PPG-700 manufactured by Nippon Emulsion Co., Ltd.

[Examples and Comparative Examples]
After 2 L of an antifoaming agent (concentration: 10 g / L) was added to the test tank filled with the synthetic resin filler, the test tank was filled with water. The antifoaming agent concentration at this time was 0.014 g / L (20 g / 1406 L). The water temperature during the test was 4 to 10 ° C.
Thereafter, the water in the test tank was circulated and the time (effect duration) until the filler surfaced on the water surface was measured (Table 1).

  FIG. 1 is a graph showing the relationship between cloud point and effect duration based on the results in Table 1. FIG. 2 is an enlarged view of the graph of FIG. 1, showing results up to an effect duration of 2000 minutes.

  The time required for the inspection such as the operation confirmation performed when the septic tank is started up is about 120 minutes (2 hours). Moreover, the standard for the filler to become familiar with water and hardly float on the water surface is about 480 minutes (8 hours) after the start of operation.

  From FIG. 2, the antifoaming agent having a cloud point of 8 ° C. or lower has an effect duration of 120 minutes (2 hours) or more, and therefore the filler does not float during the inspection such as operation check. Therefore, the movement of the filler in the water tank can also be reliably confirmed. In addition, the effect duration time of the antifoaming agent having a cloud point of 4 ° C. or less is 480 minutes (8 hours) or more, which is a guideline for the filler to become familiar with water after starting operation. Sometimes, the filler can be prevented from floating on the water surface.

Claims (12)

A method for preventing floating of a filler in which a synthetic resin filler is brought into contact with an antifoaming agent having a cloud point of 8 ° C. or lower in a water tank into which water is charged.   The method according to claim 1, wherein the antifoaming agent has a cloud point of 4 ° C. or lower.   The method according to claim 1 or 2, wherein the antifoaming agent includes a compound having a polyoxyalkylene group.   The method according to claim 1, wherein the antifoaming agent has a freezing point of 5 ° C. or less.   The method according to any one of claims 1 to 4, wherein water is further introduced into a water tank in which the filler and the antifoaming agent are introduced.   The method according to claim 5, wherein the concentration of the antifoaming agent is 0.010 to 2.9 g / L when the water is introduced to a predetermined water level in the water tank.   A method for starting up a water treatment apparatus, comprising the method for preventing the filler from rising according to any one of claims 1 to 6.   A water treatment apparatus comprising a water tank filled with a synthetic resin filler and a defoaming agent having a cloud point of 8 ° C or lower.   The water treatment apparatus according to claim 8, wherein the antifoaming agent has a cloud point of 4 ° C. or less and is put into the water tank at the time of factory shipment.   The water treatment apparatus according to claim 8 or 9, wherein the concentration of the antifoaming agent is 0.010 to 2.9 g / L when water is introduced into a predetermined water level of the water tank.   The said antifoamer is a water treatment apparatus as described in any one of Claims 8-10 containing the compound which has a polyoxyalkylene group.   A septic tank provided with the water treatment apparatus according to any one of claims 8 to 11.

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