JP4584791B2 - Stirring bar for turbid water coagulation sedimentation - Google Patents

Description

  In pursuing turbid water containing suspensions such as earth and sand to drinkable water at the time of disaster, the present invention preliminarily aggregates and precipitates the suspensions from the turbid water as a pretreatment to be processed by a water purifier. The present invention relates to a portable muddy water agitation / precipitation stirrer used for separation.

  How to secure drinking water in the event of a disaster such as an earthquake is a big problem. Even if it is not possible to carry in drinking water from non-disaster areas or even if it can be carried in, a means for purifying and using the water in the reservoir or river can be considered as a means for securing drinking water in the previous period. Unlike a permanent water purification plant, a water purification device that can be used at the time of a disaster is required to be portable and compact.

  However, particularly in the case of an earthquake, red soil or the like may flow into muddy water due to the liquefaction phenomenon of the soil in the water of the reservoir or river. When such muddy water is directly processed by a compact water purifier as described above, the filter of the water purifier is clogged immediately and cannot be used. Therefore, in order to secure drinking water at the time of disaster, it is necessary to first remove suspended matter such as earth and sand from turbid water by agglomerating, precipitating, and separating the suspended matter prior to treatment with the water purification apparatus.

As a means of coagulating and precipitating suspended matter from turbid water, a technology that puts a flocculant into sludge water discharged in civil engineering work, removes sludge components as solid waste, and discharges it to the river is ahead. (For example, Patent Document 1).
JP-A-8-168609

  However, the above-mentioned processing technique is a technique that is poor in portability because it is a processing method that can be performed only at a site where a site such as a civil engineering work site is determined and where power can always be supplied. For this reason, the above technique cannot be applied as it is in an emergency such as a disaster. Moreover, in the said processing technique, the supernatant water after removing sludge etc. is kept in mind that it discharges | emits to a river, and it does not consider until it purifies into the water which can be drunk continuously. For this reason, the said flocculant may contain the component which is not suitable for the process by the compact water purifier which is used at the time of a disaster.

  In the present invention, in order to solve the above-mentioned problems and to obtain a transparent supernatant water by coagulating and precipitating the suspended matter from turbid water and separating it effectively at the time of a disaster, , A stirring bar for turbid water coagulation precipitation in which a solid coagulant is held, and the solid coagulant contains at least an aggregation component and a thickening / adhesion component, and the aggregation component is aluminum sulfate, The main means is to use a stirring bar for turbid water coagulation sedimentation which is either polyaluminum chloride or a mixture thereof.

  In this invention, since the form of the stirring rod which hold | maintains the solid coagulant | flocculant which has the coagulation sedimentation effect | action of muddy water at one end was employ | adopted, it is convenient for carrying around and can be used anywhere. In addition, the stirring rod of the present invention is particularly effective at the time of a disaster in which power supply cannot be expected because it obtains transparent supernatant water from muddy water by stirring with human power.

  Further, in the present invention, as the flocculating component of the solid flocculant, either aluminum sulfate or polyaluminum chloride or a mixture thereof is used, so that the supernatant water treated with turbid water is then purified by a water purifier and used as drinking water. However, by using a water purifier that can reduce the burden on the filter of the water purifier and remove aluminum ions, safe drinking water can be obtained even in the event of a disaster.

  Furthermore, in the present invention, by adding a thickening / adhesive component to the solid flocculant, the solid flocculant does not elute all at once, and the amount of flocculant eluted can be controlled to the optimum amount, and repeated. Can be used.

  By adding a pH adjuster such as sodium carbonate, potassium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide and calcium hydroxide to the flocculant, turbid water into which red soil having a pH of about 5.2 was introduced. However, the surface polarity of the soil particles can be changed to effectively exhibit the agglomeration effect.

  Furthermore, when the stirrer or net-like strainer that covers the outside of the solid flocculant is provided at the tip of the side on which the solid flocculant is held, The solid flocculant can be protected even when the tip of the solid flocculant held by mistake is hit when stirring.

  Furthermore, if the stirring bar is extendable and can be fixed in the fully extended state, keep the stirring bar short except when necessary. Can be stored in a take-out bag in case of a disaster, further improving portability.

  Hereinafter, the stirring bar for turbid water coagulation precipitation of the present invention will be described in more detail with reference to the drawings. FIG. 1 is a perspective view showing an embodiment of a stirring bar for turbid water coagulation precipitation of the present invention, and FIG. 2 is an exploded view of the stirring bar for muddy water coagulation precipitation in the embodiment of FIG.

(Stir bar)
The stirring rod 1 of the present invention is a stirring rod for turbid water coagulation precipitation for coagulating and precipitating a suspension in muddy water. For this purpose, a solid flocculant 2 is held at one end of the stirring bar 1. The shape, length, thickness, and the like of the stirring rod 1 can be appropriately selected depending on the use conditions, and are not particularly limited as long as stirring is easy, but for example, considering the case of stirring turbid water in a drum can, A cylindrical stirring rod having a diameter of 3 to 5 cm and a length of 50 to 100 cm is preferable because it can be easily stirred.

  As shown in FIG. 3, the stirring bar 1 of the present invention can be made compact by storing the stirring bar 1 shorter when not used as a stretchable one (FIG. 3A). On the other hand, when used, it can be used in an expanded state (FIG. 3B). However, when stretched, it is necessary to fix the expansion and contraction in a fully stretched state so as not to be shortened during stirring.

The stirring bar 1 should be composed of a corrosion-resistant material for use in muddy water. Specific examples include polyolefin resins such as polyvinyl chloride, polyethylene, and polypropylene, resins such as nylon and epoxy, and metals such as aluminum and stainless steel.

  There is no special method for fixing and holding the solid flocculant 2 on the stirring bar 1. For example, a protrusion is provided at one end of the stirring bar 1 so that the solid flocculant 2 does not easily come off. A portion of the solid flocculant 2 added with water to form a clay is wrapped, dried, solidified, and held in a complementary shape so that the solid flocculant 2 can be fitted into the end of the stirring bar 1 It may be a method.

(strainer)
However, holding by the simple method as described above may cause the solid flocculant 2 to come off if an unexpected impact is applied to the holding end of the solid flocculant 2 when moving the stirring bar 1 or during stirring. There is a risk that. Moreover, since the solid flocculant 2 becomes small by repeated use, it becomes easy to remove | deviate gradually. Therefore, in order to hold the solid flocculant 2, the stirring rod 1 is provided with a slat-like or net-like strainer 3 that covers the outside of the solid flocculant 2 at the end on the side where the solid flocculant 2 is held. be able to. The material of the strainer 3 can be used without particular limitation as long as it has corrosion resistance like the material of the stirring rod body.

(Solid flocculant)
The flocculant 2 attached to the stirring rod 1 is a solid flocculant (solid flocculant). Liquid flocculants also exist, but there are difficulties in handling when considering use in a disaster. The solid flocculant 2 used in the present invention contains at least an aggregating component and a thickening / adhesive component. In addition, other components such as a pH adjusting component may be included.

(Aggregating component)
Generally, silica-based, aluminum-based, iron-based, and organic-based components are known as aggregating components of the aggregating agent used in civil engineering sites. In the present invention, an aluminum-based one is selected. The supernatant water from which the suspended matter has been removed with the stirring rod 1 of the present invention is then treated with a water purifier to make drinking water. Considering this, the iron-based coagulation component causes clogging of the filter of the water purifier, and the silica-based and organic coagulation component is difficult to remove these residual components with a compact water purifier. This is because the water cannot be made suitable for drinking.

  Specific examples of the aluminum-based aggregating component include aluminum sulfate and polyaluminum chloride. These can be used alone or as a mixture.

(Thickening / adhesive component)
The thickening / adhesion component is a component required because the present invention is the stirrer 1 for turbid water coagulation sedimentation at the time of disaster. The coagulant without the thickening / adhesion component dissolves the entire amount immediately, although the coagulation effect of muddy water is recognized. For this reason, in a large-scale muddy water treatment facility, there is no problem in the case of a usage method in which the flocculant is charged into the treatment facility at once and the entire amount can be used at once. However, it is not appropriate when you want to use it repeatedly after treating a small amount of muddy water at the time of a disaster, or after treating another small amount of muddy water. In the present invention, since it is considered to be used in such a disaster, the solid flocculant contains a thickening / adhesive component to enable repeated use.

  As a thickening / adhesive component, there is a thickening, it becomes a binder when dissolved in water, can adhere the particles of the individual aggregating components, and is a safe one that is recognized as a food additive It can be used if present. Specific examples include polysaccharides such as sodium alginate, alginic acid, CMC-Na (carboxymethylcellulose sodium), sodium starch glycolate, starch phosphate sodium, glucose polysaccharides, curdlan, dextran, sodium pectate, chitosan, etc. Can do. In addition, in order to enable appropriate repeated use and to ensure the aggregation performance, the blending ratio of the thickening / adhesive component is preferably 5 to 30% by weight with respect to the entire solid aggregating agent 2.

(PH adjustment component)
The present invention is used in the event of a disaster such as an earthquake. In such a situation, it is often necessary that red soil flows into a river or the like due to a sediment disaster and effectively separates it. In the case of an aggregating agent using aluminum sulfate or polyaluminum chloride as an aggregating component, the pH is about 6.5 to 7.5 for effective aggregation. However, when red soil flows in, the pH of the turbid water is about 5.2. Therefore, in order to adjust the pH of the turbid water to 6.5 to 7.5, in the present invention, the solid flocculant 2 preferably contains a basic salt pH adjusting component. Specifically, sodium carbonate, potassium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide, calcium hydroxide and the like. These compounds may be used alone or in a plurality of compounds. The pH adjusting agent is preferably 0.5 to 3% by weight with respect to the solid flocculant 2. This is because if the amount is too small or too large, the suspension in muddy water cannot be adjusted to a pH preferable for aggregation.

(Method for producing solid flocculant)
The solid flocculant 2 used in the present invention comprises a mixture of necessary components such as the above-mentioned aggregating component, thickening / adhesive component, and pH adjusting component to form a clay, and the clay-like mixture is obtained by adding a small amount of water. It can be manufactured by kneading and molding by a known method such as extrusion and evaporating the water contained by warm air or natural drying.

(how to use)
An example of the method of using the stirring rod 1 for turbid water coagulation precipitation of the present invention is schematically shown in FIG. First, muddy water 4 is put in a suitable container 5 such as a drum. The tip of the stirring bar 1 on the side where the solid flocculant 2 is held is immersed in the turbid water 4, and the turbid water is stirred with the stirring bar 1 as shown in FIG. The appropriate number of times and time of stirring vary depending on the amount of turbid water to be treated and the amount of suspended matter. From the results of Examples, about 20 g of solid flocculant 2 is immersed in 5 L of turbid water, and 10 When stirring for about 20 revolutions per second, a good effect was recognized. From this result, the calculation of the amount of water can be taken into consideration to determine the approximate stirring time / number of times. Thereafter, when the stirring bar 1 is extracted from the muddy water 4 and allowed to stand for a while, the suspension in muddy water is aggregated and precipitated, and separated from the supernatant water. Although the standing time depends on the use situation, the effect usually appears in 5 to 10 minutes.

(Treatment method for drinking water)
The supernatant water treated with the turbid water coagulating sedimentation stirring rod 1 of the present invention is then treated by a water purifier (not shown). The supernatant water contains aluminum ions in the above treatment. For this reason, the water purifier used for purifying even the drinking water using the supernatant liquid is required to be capable of removing aluminum ions. Specific examples include a water purifier using a cation exchange resin and a water purifier using a reverse osmosis membrane. Moreover, since it is preferable that it can be used at the time of a disaster, the thing which can be carried compactly and the power source is an unnecessary type or a power saving type which can be operated by a battery or the like is preferable. Water treated with such a water purifier can be used as drinking water that can be safely consumed even in a disaster.

(Manufacturing)
100 g of “Solid Ace NCC” (manufactured by Nippon Solid Co., Ltd.), which is an aggregating agent having 31 to 36% of aluminum sulfate as an aggregating component, was pulverized into powder. 35 mL of pure water was added to this and kneaded by hand to make a clay. Further, 1 g of sodium carbonate and 10 g of sodium alginate were added and kneaded again. This was formed into a cylindrical shape having a diameter of 20 mm and a length of 80 mm by hand, and naturally dried to obtain a solid flocculant used in the present invention.

  The solid flocculant obtained above is attached to the attachment portion of a cylindrical stirring rod having a length of about 600 mm and a diameter of about 20 mm having an attachment portion at one end, and a slat-like strainer is attached to the solid flocculant. It attached to the stirring rod so that it might cover from the outside, and obtained the stirring rod for muddy water aggregation precipitation of this invention.

(Evaluation 1)
4 L of tap water (water temperature 28 ° C.) was placed in a 5 L beaker. The solid flocculant part of the stirring rod of the present invention obtained above was placed in this water, and stirred at a speed of 30 sets per minute, with 2 sets of right turn and 2 sets of left turn. Since the solid flocculant became difficult to elute as the saturation concentration was approached, tap water was replaced every 5 minutes during stirring, and stirring was continued under the same conditions, and a decrease in the solid flocculant was observed. The dry weight of the flocculant used in Evaluation 1 was 22.4 g, but when 1350 sets (total water immersion time of 45 minutes) were completed, the flocculant was still left at the tip of the stirring rod, The weight of the solid flocculant included was 22.5 g. Further, 2100 sets (total water immersion time: 70 minutes) were carried out, but the solid flocculant still remained at the tip of the stirring rod, and the weight of the solid flocculant including water was 21.7 g.

  For comparison, the solid flocculant was replaced with 23.2 g of “Solid Ace NCC” and similarly attached to a stir bar, and an experiment was carried out under the same conditions. When 1350 sets (total immersion time of 45 minutes) were completed, “Solid Ace NCC” was dissolved from the tip of the stirring bar and disappeared.

(Evaluation 2)
A 10 L beaker was charged with 5 L of water and 50 g of red soil, and mixed to prepare a sample of muddy water in which red soil was suspended. The solid agglomerated portion of the stirring rod of the present invention (solid aggregating agent 20 g) obtained above was immersed in this, stirred for 20 seconds for 20 revolutions, and allowed to stand for 5 minutes. As a result, most of the red soil component became mud. Precipitated. When allowed to stand for another 25 minutes (30 minutes in total), water and mud components were clearly separated, and the supernatant water was almost transparent. The pH of the water at this time was 6.8.

  For comparison, the solid flocculant was changed to 20 g of “Solid Ace NCC”, and the same experiment was conducted. As a result, no coagulation / precipitation effect was observed even after standing for 5 minutes. Furthermore, when left standing for 25 minutes (total 30 minutes), the red soil as a suspension stopped in a state where only a part of the component that seems to have a high specific gravity is precipitated, and the transparency of the water remains almost unchanged. It remained. The pH of the water at this time was 5.3.

  The stirring bar for turbid water aggregation precipitation of the present invention is used as a stirring bar for agglomerating and removing suspension from the turbid water as a pretreatment for securing drinking water from the turbid water, to obtain transparent supernatant water, at the time of disaster, etc. It can be used particularly effectively for industrial use.

It is the perspective view which showed the one aspect | mode of the stirring rod for muddy water aggregation precipitation of this invention. It is an exploded view of the stirring rod for turbid water aggregation precipitation of this invention. It is a perspective view which shows the time of (A) shortening and the time of (B) expansion | extension of the stirring rod for muddy water aggregation precipitation of this invention. It is the figure which showed typically the method of using the stirring rod for muddy water aggregation precipitation of this invention.

Explanation of symbols

1 Stirring bar 2 Solid flocculant 3 Strainer 4 Turbid water 5 Container

Claims (6)

It is a stirring bar for turbid water coagulation precipitation in which a solid flocculant is held at one end of the stirring bar,
The solid flocculant contains at least an aggregating component and a thickening / adhesive component,
A stirring bar for turbid water coagulation precipitation, wherein the coagulation component is any of aluminum sulfate, polyaluminum chloride or a mixture thereof.   The solid aggregating agent is one or more selected from the group consisting of sodium carbonate, potassium carbonate, calcium carbonate, sodium hydroxide, potassium hydroxide and calcium hydroxide in addition to the aggregation component and the thickening / adhesion component The stirring bar for turbid water coagulation precipitation according to claim 1, comprising a pH adjusting component comprising a compound.   The stirring rod for turbid water coagulating precipitation according to claim 1 or 2, wherein the thickening / adhesive component is a polysaccharide.   The said stirring rod has a slat-like or net-like strainer which covers the outer side of the said solid flocculant at the end by which the said solid flocculant is hold | maintained. The stir bar for turbid water coagulation precipitation described.   The stirring rod for turbid water coagulating precipitation according to any one of claims 1 to 4, wherein the stirring rod can be expanded and contracted and the expansion and contraction can be fixed in a fully extended state. After stirring the turbid water with the stirring rod by immersing the tip on the side where the solid flocculant of the stirring rod for turbid water aggregation precipitation according to any one of claims 1 to 5 is retained in the turbid water, A step of aggregating and precipitating the suspension in the muddy water by allowing to stand, and separating the suspension and supernatant water;
A method for treating turbid water comprising at least a step of obtaining drinking water by treating the supernatant water obtained in the step with a water purifier capable of removing aluminum ions.

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