JP2006057449A - Riverbed block for purifying water quality in rivers - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a riverbed block for purifying water quality excellent in the efficiency, capacity and durability of water quality purification per unit space, and sufficiently economical for practical application. <P>SOLUTION: It is a porous square cubic body with its top surface protruding upward. Provided as a riverbed block for purifying water quality, this porous body consists of many porous particles each having many fine pores and combined with other particles by cement into a sponge-like form containing the meshes of clearances larger than the fine pores of the particles communicating with one another. More preferably, a riverbed block for purifying water quality of this construction, additionally having a recess on the top face of the body which communicates with lateral hollows for passing water on the sides of the body is provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water quality purification river bed block used for a river bed that contributes to purification of water quality in a river.

  Direct water purification methods such as the contact material-filled water channel purification method and the gravel contact oxidation method are expected as water quality purification methods for water areas where pollution due to domestic wastewater from rivers is advancing. However, a purification technology that is excellent in purification efficiency and economical enough to be put to practical use has not yet been established.

Although attempts have been made to lay down metal mesh bags filled with charcoal or gravel on the riverbed and decompose organic matter by the action of microorganisms, the use of charcoal is expensive and cannot be put into practical use. In addition, the use of gravel has a problem that purification efficiency is poor because the existence of biofilm per unit space is not so large. Attempts have also been made to research and develop porous blocks produced by firing, but it is difficult to control voids by firing techniques and is expensive, and thus cannot be put to practical use.

  The present invention solves such problems, and is excellent in water purification efficiency per unit space, excellent in water purification capability, excellent in permanence of water purification capability, and extremely economical enough to be put to practical use. The purpose is to provide a river block for water purification.

According to the present invention, a solid body having a top surface, a side surface, and a bottom surface, wherein at least a part of the top surface projects upward and the solid particles having a large number of pores are bonded to each other by cement. There is provided a river bed block for purifying water quality of a river, characterized in that it is a porous body formed by connecting voids larger than the pores of the porous particles between the porous particles in a spongy mesh shape. The

Moreover, in this invention, it is preferable that the upper-surface center part of the said solid solid protrudes upwards rather than a peripheral part. Furthermore, it is preferable that the top surface shape of the right solid is a trapezoid. Moreover, it is preferable that the said right solid is provided with at least 1 or more recessed part in the upper surface. Further, it is preferable that at least one or more recesses are provided on the upper surface of the solid body, and a lateral water passing cavity is provided on the side portion so as to communicate with the recesses.

The river water purification block for river water of the present invention (hereinafter referred to as the block of the present invention) purifies water by the oxidizing action of an aerobic microbial membrane that is deposited in the pores of porous particles. The surface area per unit space of the aerobic microbial membrane that contributes to purification is extremely large. As a result, the block of the present invention is excellent in water purification efficiency per unit space.

In addition, since water rich in dissolved oxygen is supplied to the aerobic microbial membrane from the gaps between the porous particles having a large pore size communicating with the sponge network, the activity of the aerobic microbial membrane is enhanced, and the water purification capability of the present invention Reaches a high level. Further, since the block of the present invention has a protrusion on the upper surface, the water flow becomes a turbulent state, and the oxygen-rich water easily flows into the voids between the porous particles. Is supplied to the microbial membrane, the water purification effect of the microbial membrane is maintained for a long time. As a result, the water purification capacity of the block of the present invention is maintained for a long time without any deterioration.

Hereinafter, the block of the present invention will be described with reference to FIGS. FIG. 1 shows an example of the block of the present invention. The block of the present invention has a trapezoidal cross-sectional shape on the upper surface and is a porous body. FIG. 2 is a diagram schematically showing a local enlarged view of the cut surface of the block of the present invention.

Each porous particle 2 is bonded to each other with cement 4 and is a porous body having a microstructure in which a void 5 between porous particles is formed.
Each porous particle 2 has a very large number of pores 3 having a pore diameter of 3 mm or less. And the cement 4 which joins each porous particle 2 has joined between each porous particle to such an extent that the porosity of the porous particle 2 is not reduced as much as possible, and the required intensity | strength is expressed.

Therefore, most of the pores 3 present in the porous particles 2 are configured to communicate with the voids 5 between the porous particles having a larger pore diameter than the pores 3. The voids 5 between the porous particles communicate with each other in the form of a sponge mesh, and are connected to the surface of the block 1 of the present invention.

FIG. 3 is a view showing a state in which the block of the present invention is laid on the riverbed.
River water penetrates into the voids 5 between the porous particles, and further penetrates into the pores 3 of the porous particles. The aerobic biofilm is deposited on the pore wall of the void 5 and the pore wall of the pore 3, respectively. Since the aerobic biofilm prefers pores having a small pore diameter, it is particularly easy to deposit on the pore wall of the pore 3.

Therefore, the surface area of the biofilm per unit volume existing in the block 1 of the present invention is characterized by being remarkably large.
Further, the porous interparticle void 5 is a void having a relatively large pore diameter of, for example, 5 mm or more, so that it is excellent in water permeability and supplies water rich in dissolved oxygen to the aerobic bacteria that are deposited in the pore 3. Therefore, the aerobic bacteria are activated, and the water purification ability of the aerobic bacteria is suitably maintained at a high level.

As a result, the water purification capacity of the block of the present invention is suitably maintained at a high level. In addition, since the upper surface of the block of the present invention shown in FIG. 1 has a trapezoidal cross section, the water flow flowing through the block area of the present invention laid on the river bed becomes a turbulent state, and oxygen easily dissolves in the river water. This brings about an effect that river water easily flows into the block of the present invention.

Furthermore, in the case of an embodiment in which the block of the present invention has a concave portion on the upper surface and a lateral cavity communicating with the concave portion on the side, water rich in dissolved oxygen is further supplied to each portion of the block of the present invention. As a result, it is possible to obtain an effect that the purification ability and the durability of the purification ability of the block of the present invention are further improved.

Examples of the present invention will be described in detail below, but the present invention is not limited to these examples.

A block of the present invention using clinker ash generated from a first dust collector of a thermal power plant as porous particles will be described.
In the production of ordinary concrete products, filling is carried out as densely as possible so as not to cause poor filling of the kneaded material during molding. However, in the production of the block of the present invention, the technical problem to be produced is completely different from the conventional concrete product.

A technical problem in the production of the block of the present invention is that excessive cement slurry is not generated in the process from kneading to curing. That is, the amount of the cement slurry for joining the porous particles is a necessary and sufficient amount, and the cement slurry does not ooze out to the surface of the block of the present invention.

A method for producing the block of the present invention without clogging the pores of the clinker ash will be described based on the production process diagram shown in FIG.
The clinker ash discharged from the first dust collector of the thermal power plant is classified through a sieve. The composition of the clinker ash used varies depending on the type of coal used in the thermal power plant. The maximum value of the alumina content was 29.9%, the minimum value was 18.0%, and the average value was 24.9%. The maximum value of silica content was 67.8%, the minimum value was 52.2%, and the average value was 58.5%. The pH of water when these clinker ash was immersed in water was 8.2. The pore volume per gram was 0.15 to 0.06 cubic meters.

1000 kg of clinker ash classified to 5 to 15 mm is weighed, and water corresponding to 25% of the moisture content of clinker ash is added to 1000 kg of clinker ash and mixed. A clinker ash containing a predetermined amount of water is charged into the mixer.

On the other hand, 100 to 200 kg of sand and 280 to 320 kg of cement are mixed to obtain a uniform mixture. This homogeneous mixture is placed in a mixer charged with the clinker ash and mixed.
Next, 30 to 100 g of water is added and kneaded.
The kneaded material kneaded uniformly is put into a mold having the trapezoidal cross section shown in FIG. 1 and filled into the mold while striking with a stick. So-called squeeze molding. After completion of curing for a predetermined time, the mold is released to obtain the block of the present invention.

The reason why a predetermined amount of water is added to the clinker ash in advance to contain water is to prevent the pores of the clinker ash from being clogged with cement during kneading and to alleviate a sudden change in the kneading state. Further, the reason why water is not contained until the saturated state is that excessive cement slurry is not generated during kneading. Therefore, it is preferable to keep the water content of the clinker ash in the range of 50% or less.

The state of the kneaded product at the time of kneading is preferably a state in which the wet kneaded product is divided into several parts or broken apart even when gripped in a dumpling shape. In such a kneaded state, water contained in the porous particles oozes out during molding, and a cement slurry state suitable for joining the porous particles during molding is obtained. It is preferable to apply a cement curing retarder to the surface of the mold because the cement slurry that has leached out to the surface of the molded body is not cured.

Since a large clinker ash having a size of 5 to 15 mm is used, voids of 5 mm or more are formed in a sponge network between the porous particles. Further, most of the pores of the clinker ash are not clogged with cement, and further have a necessary strength as a cured product after release.

The cement is preferably an early strong cement. Since the kneaded product is put into a mold, formed into a mold, and cemented with fluidity before it is cured, the clinker ash surface is prevented from being coated, which is preferable. It is preferable to add a hardening accelerator because the fluidity of the cement slurry is reduced in a short time and the cement slurry is prevented from covering the clinker ash surface more than necessary. More preferably.

As a result, most of the pores of the clinker ash are communicated with a 5 mm or more spongy mesh-like void formed between the clinker ash.
It is preferable to add sand together with cement because the strength increases.
The physical properties of the obtained block of the present invention are porosity VC ≧ 20%, compressive strength σ ≧ 10 N / mm ² , and water permeability coefficient KC ≧ 1 × 10 ⁻¹ .

Here, the pore diameter of the pores 3 present in the porous particles 2, the pore diameter of the gaps between the porous particles, and the size of the porous particles will be described.
FIG. 5 (5a) is an example of a local cross section of the clinker ash, and the pore diameter of the pore 3 existing in the porous particle 2 is the same as the cross sectional area of the pore as shown in FIG. 5 (5b). It is indicated by the diameter D (circle equivalent diameter) of the circle.
The pore diameter of the void between the porous particles surrounded by the porous particle group and the cement is also indicated by the diameter of a circle having the same cross-sectional area as the cross-sectional area of the void between the porous particles.
Furthermore, the size of the porous particles is also indicated by the diameter of a circle having the same cross-sectional area as that of the porous particles.

As a riverbed block for rivers, the weight of the riverbed block per unit may be more than a predetermined value depending on the flow rate of the river water. In this case, as shown in FIG. A two-layer water purification riverbed block 10 in which cement mortar 9 is applied to one side of a concrete block base 8 formed into a shape and the block 1 of the present invention is joined is preferable.

Further, the water quality purification river bed block 10 having a two-layer structure in which the block 1 and the concrete block 8 of the present invention are continuously formed in one mold and integrated is preferable. The joint portion of the riverbed block 10 manufactured by this method is preferable because the concrete 8 bites into the porous portion of the block 1 of the present invention and becomes an anchor effect and the joint strength is improved.

The riverbed block for water purification having the shape shown in FIG. 6 is laid on the river for 10 square meters (10), the biofilm is deposited on the block 1 of the present invention, removed from the river after 20 days, and the artificial waterway installed indoors. The water sampled from the river was installed on the floor and circulated with a circulation pump, and the purification data of the river water by the block 1 of the present invention was measured.

In addition, a water wheel is installed in the middle of the water circulation path, and dissolved oxygen in the water is consumed and reduced by purification, while oxygen is replenished in the water to make it as close to a natural river as possible, and water is supplied every elapsed day. It collected and measured about each transition of BOD, COD, ammonium ion, phosphorus, nitrogen, and PH. The results are shown in Tables 1 to 6 and FIGS.

The comparative example shown together with the embodiment of the present invention in FIGS. 7 to 12 is all except that the gravel is used instead of the aggregate clinker ash in the manufacturing method of the block 1 of the present invention used in the present embodiment. It is the purification | cleaning data result measured by the method same as a present Example using the comparison body produced on the same conditions and the method as a present Example.

FIG. 7 shows the relationship between the BOD value and the elapsed days. FIG. 8 shows the relationship between the COD value and the elapsed days. FIG. 9 shows the relationship between the ammonia ion value and the elapsed days.
FIG. 10 shows the relationship between the total phosphorus value and the elapsed days. FIG. 11 shows the relationship between the total nitrogen value and the elapsed days. FIG. 12 shows the relationship between the PH value and the elapsed days.
BOD and the like were measured according to JIS standards.

The kneaded material prepared by the same method as in Example 1 is put into a mold, and the block 11 of the present invention having the shape shown in FIG. 13 is prepared. FIG. 13 (13a) is a sectional view of the central portion of the block 11 of the present invention, and (13b) is a perspective view.

A feature of the present invention is that a recess 12 is provided at the center of the upper surface of the block 11 of the present invention. Since the recess 12 is provided, the river water is more widely permeated into the pores of each part of the block 11 of the present invention, so that the water purification capability is maintained at a high level even on the bottom side of the block of the present invention. Is done.

The kneaded material produced by the same method as in Example 1 is put into a mold, and the block 13 of the present invention having the shape shown in FIG. 14 is produced. FIG. 14 (14a) is a sectional view of the central portion of the block 13 of the present invention. (14b) is a perspective view.

A lateral hole 14 communicating with the side portion of the recess 12 provided in the central portion of the upper surface of the block 13 of the present invention is provided in the side portion of the block 13 of the present invention, and a notch extending vertically to the position of the side portion provided with the lateral hole. This is a block 13 of the present invention having a structure in which a portion 15 is provided. FIG. 14 (14 c) shows a state in which a large number of the blocks 13 of the present invention are laid on the riverbed as water-purifying hardened bodies.

FIG. 14 (14c) is a top view. As shown in FIG. 14 (14 c), the upper and lower cutout portions 15 provided on the side portions of the adjacent block 13 of the present invention are provided at positions where they coincide with each other, so that water from the upstream side Not only the recess 12 provided on the upper surface of the block 13 of the invention but also the lateral hole 14 provided on the side of the block 13 of the present invention, the water between the porous particles is passed, It becomes easy to penetrate | invade into the pore of each part of the block 13 of this invention more widely.

In addition, the cutout portion 15, the side hole 14, and the concave portion 12 provided on the side portion of the block 13 of the present invention serve as a living room for small animals, and the effect of creating a naturally friendly environment by promoting a good food chain is also obtained. This is preferable. The water rich in dissolved oxygen is continuously supplied to the biofilms that are implanted in the pores 3 of each part of the block 13 of the present invention, and the purification ability of the biofilms is activated and maintained for a long time.

The kneaded material produced by the same method as in Example 1 is put into a mold, and the block 16 of the present invention having the shape shown in FIG. 15 is produced. Since the columnar body 17 projecting upward at the four corners of the block 16 of the present invention has a shape surrounding the concave portion 12 at the center of the block 16 of the present invention, when this cured body is used as a riverbed block, On the other hand, since the columnar body 17 becomes a resistor, the flow of water is changed, and the retention time of the water is increased, so that the effect of purifying water by the biofilm in the cured body pores is improved.

The present invention is not limited to the above embodiment. Examples of various embodiments as blocks of the present invention are shown in FIGS. FIG. 16 shows a top view when the cylindrical block 18 of the present invention is laid on the riverbed. The block 18 of the present invention has a structure having a recess 12 at the center of the upper surface and a lateral hole 14 communicating with the recess 12. FIG. 17 is a top view when a block 19 of the present invention having a hexagonal prism shape is laid on the riverbed of a river.

The block 19 according to the present invention has a structure in which a recess 12, a lateral hole 14 communicating with the recess 12, and a notch 15 extending vertically are provided at a position where the lateral hole 14 is connected to a side portion of the cured body 19.

FIG. 18 is a top view in which a large number of pentagonal prism-shaped blocks 20 of the present invention are laid as described above. In this embodiment, the positions of the cutout portions 15 of the adjacent cured bodies 20 do not coincide with each other, but the positions of the cutout portions 15 of the adjacent cured bodies coincide with the horizontal holes 14. FIG. 19 is a top view in which a large number of blocks 21 of the present invention having a rectangular parallelepiped shape are laid as described above.

The river water purification block according to the present invention is excellent in river water purification capacity, purification efficiency, and durability of water purification, and can be reduced to a practical level. Can be suitably used.

The perspective view of the river-bed block for water quality purification of this invention whose upper cross section is trapezoid is shown. It is the figure which showed typically the local enlarged view of the cut surface of the block of this invention. The perspective view which laid many blocks of the present invention on the riverbed of a river is shown. It is a manufacturing-process figure of the block of this invention. (5a) It is an example of the local cross section in case the porous particle used by this invention is a clinker ash. (2b) It is a figure which shows the hole diameter of the pore which exists in a porous particle. 2 shows a two-layer river bed block using the block of the present invention. The relationship between the water quality purification data of a river water by a block of the present invention, a BOD value, and elapsed days is shown. The relationship between the COD value and the elapsed days is shown. The relationship between ammonia ion value and elapsed days is shown. The relationship between total phosphorus value and elapsed days is shown. The relationship between the total nitrogen value and the number of days elapsed is shown. The relationship between PH value and elapsed days is shown. The figure which shows another embodiment of the block of this invention, (13a) is a center sectional view (13b), and shows a perspective view. The figure which shows another embodiment of the block of this invention, (14a) is a center sectional view (14b), and shows a perspective view. (14c) shows a top view when a number of blocks of the present invention are laid on the river bed. The figure which shows another embodiment of the block of this invention, (15a) is a perspective view, (15b) shows the top view at the time of laying many blocks of this invention on the riverbed of a river. The top view of one Example which laid many blocks of the present invention on the riverbed is shown. The top view of one Example which laid many blocks of the present invention on the riverbed is shown. The top view of one Example which laid many blocks of the present invention on the riverbed is shown. The top view of one Example which laid many blocks of this invention on the riverbed is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... River bed for water purification of this invention 2 ... Porous particle 3 ... Pore of porous particle 4 ... Cement 5 ... Porous space between porous particles 6 ... Sand particle 10 ... River bed of 2 layer structure Block 11... Block according to the present invention in which a concave portion is provided in the center of the upper surface 12... Recess 13. Block according to the present invention having a recess and a horizontal hole 14. Horizontal hole 15.

Claims (6)

A solid body having an upper surface, a side surface, and a bottom surface, wherein at least a part of the upper surface protrudes upward and porous particles having a large number of pores are bonded to each other with cement, the porous body River bed block for purifying water quality of rivers, characterized in that it is a porous body formed by connecting pores larger than the pores of the porous particles in a spongy mesh pattern between the particles The river block for purifying water quality of a river according to claim 1, wherein the central part of the upper surface of the solid body protrudes upward from the peripheral part. The river bed block for water quality purification of a river according to claim 1, wherein the upper surface cross-sectional shape of the right solid is a trapezoid. The river bed block for water quality purification of a river according to claim 1, wherein the solid body is provided with at least one recess on the upper surface. The at least one concave portion is provided on the upper surface of the solid body, and a lateral water passing cavity portion is provided on a side portion so as to communicate with the concave portion. River bed blocks for water quality purification of rivers as described in 1. The river bed block for water quality purification of a river according to claim 1, wherein the porous particles are clinker ash.

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