JPH0783808B2 - Porous media - Google Patents

Description

Detailed Description of the Invention

[0001]

[Field of Industrial Application] The present invention relates to a contact oxidation filter medium for a wastewater treatment facility for household, office, school, food industry, livestock facility, etc., a filter for water purification method, and a filter medium for water. Etc. are related to filter media for water treatment.

[0002]

2. Description of the Related Art Filter media for water treatment such as sprinkling filter method, fixed bed aeration method, contact aeration method, etc. have been mainly crushed stones, gravel sand, ceramics, plastic pipes, etc. It formed a microbial film on the surface of the urine and promoted bio-oxidation. Recently, pumice, crushed zeolite, crushed Asama stone,
There are some examples of using porous materials such as charcoal and porous ceramics. However, all of these are microbial film effects mainly on the surface of the object, and deep inside the object, the growth of microorganisms progresses, and filter media that the entire inner and outer layers serve as a place for microbial growth still appear. Absent.

[0003]

The present invention is porous from the surface to the inner layer, is excellent in breathability, water permeability and water retention, has sufficient strength and durability, and is suitable for implantation and growth of aquatic microorganisms. It is to provide a rational filter material for water treatment.

[0004]

In order to solve the above problems, the present inventor has conducted extensive studies for many years, and as a result, crushed porous sludge and charcoal (including bamboo charcoal, the same applies hereinafter) to an appropriate size and sieve. A separate coarse-grained mixture is used as an aggregate, and a novel porous binder mixed with a skeleton fiber is added to this and kneaded, and the mixture is molded and cured, and it is found that the problem can be solved brilliantly, and the present invention is provided. It came to completion. That is, the present invention provides (1) a mixture obtained by adding 30 to 50% by volume of a granular material of a porous mint and 10 to 40% by volume of a granular material of charcoal and / or bamboo charcoal and adding a solution containing water or nitrogen or phosphorus. (2) 10 to 20% by volume of cement, 5 to 10% by volume of sand, 5 to 15% by volume of charcoal and / or bamboo charcoal powder or diatomaceous earth or a mixture thereof, and 0 to 3% by volume of bentonite.
0.1 to 0.5% by weight of the total amount of the crushed material or the crushed suspension of the kin fiber is added to the mixture, and the mixture is hydro-kneaded to give a kneaded product, and the mixture of (1) and (2) This is a porous filter medium obtained by kneading the kneaded product, shaping the kneaded product into a desired shape, placing the kneaded product in a steam chamber heated to 63 ° C. ± 3 ° C., and curing and aging for 12 to 24 hours.

The present invention will be specifically described below. The porous skeleton used in the mixture (1) of the present invention is natural pumice, zeolite, asama stone and the like. These are used by sieving as they are or by crushing after crushing stones and using granules having a particle size of 2 to 8 mm at a rate of 30 to 50% by volume. Since the surface of the porous rod has numerous large and small pores and is continuous up to the inner layer, it has large air permeability, water absorption and water retention, and microorganisms can easily land and inhabit. Since the particle diameter is too small below 2 mm and too large above 8 mm, those having a particle diameter in the range of 2 to 8 mm are suitable and are the main constituent of the composition of the porous filter medium of the present invention. For the charcoal granules, black charcoal with sufficient hardness that does not leave uncarbonized tar content is crushed and sieved to a diameter of 2 to 8 mm, which is used in an amount of 10 to 40% by volume. Charcoal has been used for a variety of purposes in addition to fuel since ancient times. It has a large number of pores from the surface to the inner layer, excellent breathability, water absorption and water retention due to the distribution of pores, and strong decolorization, deodorization, and adsorption. That is. Activated carbon has the most enhanced properties, and has recently been widely used in the water treatment field as a decolorizing agent for water, a deodorizing agent, a clarifying agent, and the like. The particle size of the charcoal granules is similar to that of the porous minsk, and the range of diameter 2 to 8 mm is preferable, and the mixing amount needs to be 10% by volume or more to maintain the characteristics of charcoal, and if it exceeds 40% by volume, the whole Is not preferable because the hardness and strength of the are decreased.

According to the experiment, as a result of being immersed in a wastewater treatment water tank for 6 months, pumice, zeolite, and charcoal in the form of solid lumps were all surface-implanted with microorganisms and partially adhered to sludge due to habitation. However, when the lumps were broken and the inside was observed, almost no invasion of microorganisms was observed in the inside, and sludge formation was not observed. In the same experiment, pumice, zeolite, and charcoal were crushed into fine powder, which was packed in a gauze bag and then treated in the same manner as the above experiment. Although it was not stable, microbial implantation was observed on the surface. However, no invasion of microorganisms was confirmed inside. Such a phenomenon is a cause of impeding the invasion and reproduction of microorganisms, because tangible lumps and those packed with fine powder are not sufficiently ventilated and the movement of water inside. Is judged. Therefore, the present invention, in order to improve this drawback, a mixture of a porous mining and charcoal aligned in particles of an appropriate size as an aggregate, using a novel porous binder between the particles, for example, By coarsely binding and hardening it in a scalloped state, it has a large void from the surface to the inner layer and is suitable for the implantation, habitation and growth of microorganisms that are free of aeration and water permeability. This is the reason for the idea of the porous filter medium of the present invention.

In the present invention, the reason why water and water are absorbed in advance in obtaining the mixture of the porous minced granules (1) and the charcoal granules is that the mixture of (1) and the kneaded mixture of (2) are combined. In order to prevent the deterioration of the function of the charcoal when it is hardened, the colloidal fine particles such as cement are not sucked into the pores of the porous minnow and the charcoal during the water addition and kneading when obtaining the kneaded mixture. This is to prevent an obstacle caused by. Therefore, the amount of water added when preparing the mixture of (1) must be sufficient to exceed the amount of water absorption.

Next, the cement used as a binder for obtaining the kneaded product of (2) should be of a quality with as low an alkali content as possible in order to utilize the product, and to obtain a sufficient amount of the product. 10-2 because it is necessary to maintain strength
0% by volume is suitable. In addition, as a result of an experiment for making the binder porous, when charcoal powder or diatomaceous earth and a mixture thereof of 5 to 15% by volume were mixed and used in cement, the binder was porous and absorbed water while maintaining the strength of the binder itself. It turned out that it becomes an excellent thing. At this time, if necessary, if bentonite (within 3% by volume) is mixed, an appropriate caking property at the time of kneading can be increased. The water addition and kneading operations for obtaining the kneaded product of (2) are sufficiently performed to the extent that a soft viscous body is maintained.

When the mixture of (1) and the kneaded product of (2) are kneaded, a necessary amount of water is added and kneaded.
The amount of water added is convenient for molding when the kneaded product is slightly hard to finish. Molded product is blown with steam at 63 ° C ±
Put in a steam chamber adjusted to 3 ° C., and cure and age for 12 to 24 hours. The molded product released from the steam chamber is a product after being left to cool, but it can be further matured after being dipped in water for an appropriate period of time and drained to obtain a finished product. In addition, a curing time can be shortened by using an early strengthening agent during the above kneading.
To obtain the mixture of (1), a solution prepared so as to contain nitrogen and phosphorus in an amount of 50 to 100 mg is sprinkled into and absorbed by a total of 1 liter of the porous lantern granular material and the charcoal granular material. As compared with the case of simply adding water, it was found that nutrients for microorganisms were endowed, aquatic microorganisms were more likely to be implanted and proliferated, and that microbial activity proceeded rapidly to the inner layer.

When obtaining the kneaded product of (2), 0.1 to 0.5% by weight of the total amount of the materials used, such as glass wool, rock wool, and asbestos, are unwound during hydro-kneading. By crushing or adding and mixing as a crushing suspension, the mine fibers control the bridging action between the particles of the granules and form the network structure of the binder, which increases the elasticity of the product and destroys it. It was confirmed that the strength was remarkably improved. Even if the product is immersed in water for a long time,
Further, even if they are stacked in the tank, they do not cause any collapse and can maintain a stable shape. further,
The mint fiber is expected to be an excellent place for the implantation of aquatic microorganisms.

[0011]

EXAMPLES Examples of the present invention and experimental examples will be described. (Experimental Example 1) The product of the present invention shown in Example 1
The following are the results of observing the strength survey, the implantation of aquatic microorganisms, and the habitation status of the fish that were submerged in the wastewater treatment process water tank for 10 months from August to August 1992. (1) Maintain the original shape even if the specimen is dropped from a height of 1 m onto a concrete floor. (2) When a sample is smashed with nata, it has elasticity and a flat cut surface appears. (3) It was confirmed that about 70% of the surface of the sample was covered with the implanted microbial film, and the biofilm invaded the inner layer and proliferated. (4) When the sample is broken and the surface and inner layer liquid is observed with a microscope, in addition to various active fungi, protozoa such as flagellates and nematodes are actively moving around, and sludge in the inner layer is eaten. It was confirmed that the worms live and are active.

(Experimental Example 2) According to the results of the test, the product of the present invention was used as a fixed-bed contact filter medium in the aeration tank of a sewage treatment test plant having a daily treatment capacity of 500 liters.
Regarding OD, the treated water was not detected in 78 mg of the raw water, and the BOD removal rate was 99% or more. For ammonia nitrogen (AN), the treated water was 0.2 ppm, the A.N was 29.6 ppm. The N removal rate was 99% or more, and the transparency was transparent and odorless when the treated water was 1 m or more with respect to the raw water 8.5.

Example 1 Pumice stone granular product (diameter 2 to 8 mm)
6.3 liters and bamboo charcoal granules (diameter 2-8 mm) 4.2 liters were mixed, and ammonium sulfate and ammonium phosphorus were dissolved in water,
A solution prepared by dissolving 50 ml of a solution adjusted to N 3% and P 3% in 1.7 liters of water is mixed and absorbed to form a mixture. Separately, 2.4 liters of cement, 0.9 liters of bamboo charcoal powder, 0.9 liters of sand, and 0.3 liters of bentonite were mixed, and 30 g of glass wool was crushed and suspended in 1 liter of water. In addition, kneading is performed while adding 0.7 liter of water to obtain a kneaded product. After thoroughly mixing the above mixture and the kneaded product together, the bottom surface diameter 4c
m, upper diameter 5.5 cm, depth 6 cm in a plastic cup. This was heated with live steam at 63 ° C ± 3
Put in a steam room at ℃. After 15 hours, it was taken out from the steam chamber, allowed to cool, and then removed from the mold to obtain 12 liters (128 pieces) of the porous filter medium of the present invention as a solid.

(Example 2) Zeolite granular product (diameter 2 to 8)
mm) 6.3 liters and charcoal granules (diameter 2-8 mm)
4.2 liters are mixed, 1.7 liters of water are mixed with this, and water is absorbed to form a mixture. Separately, cement 2.4
1 liter, diatomaceous earth 0.9 liter, sand 1 liter, bentonite 0.2 liter are mixed, and 30 g of rock wool is crushed and added to the mixture, and kneaded with 1.8 liter of water to obtain a kneaded product. To do. After the above mixture and the kneaded product are combined and sufficiently kneaded, the mixture is molded into a plastic cup having a bottom diameter of 4 cm, an upper diameter of 5.5 cm and a depth of 6 cm. This is put in the steam quality of 63 ° C ± 3 ° C heated by live steam. After 12 hours, the product was taken out from the vapor and allowed to cool, then the product removed from the mold was immersed in water for 5 days, pulled up and air-dried, and then 12 liters of the porous filter medium of the present invention (12
4 pieces) were obtained.

[0015]

As described above, the porous filter medium of the present invention is
Since it is composed of large and small porous pores that are not found in conventional filter media, it has extremely high air permeability and water permeability and is suitable for habitat of aquatic microorganisms.Therefore, active bacteria and fungi from the surface of the filter media to the inner layer Implants and proliferates microbial groups such as algae, algae, protozoa, ringworms, and nematodes, and is active and active.
Therefore, the biochemical oxidation ability was increased, and the BOD removal efficiency of the wastewater treatment facility using the porous filter medium of the present invention as the fixed bed filter medium was a remarkable effect of 99% or more. Further, the charcoal, which is a constituent material of the porous filter medium of the present invention, itself has various removal efficiencies such as adsorption, decolorization and deodorization, so that the treatment effect is further enhanced. Since the porous filter medium of the present invention does not contain any harmful substances or dangerous substances, it is safe to use, and has sufficient strength and durability in use. It is a safe and naturally friendly material even when it is finally landfilled after use. As described above, the porous filter medium of the present invention is sure to exert a great effect on the improvement and purification of water quality, and provides an epoch-making material for the improvement of the modern global environment where clear treated water is sometimes required. It is a thing.

Claims (1)

[Claims] 1. (1) 30 to 50% by volume of a granular material of porous minsk and 10 to 40% by volume of a granular material of charcoal and / or bamboo charcoal
To the above, a solution containing water or nitrogen and phosphorus is added and mixed to form a mixture. (2) Cement 10 to 20% by volume, sand 5 to 1
0% by volume, charcoal and / or bamboo charcoal powder or diatomaceous earth or a mixture thereof 5-15% by volume and bentonite 0-3
To the volume%, 0.1 to 0.5% by weight of the total amount of the crushed material or the crushed suspension of the rust fiber is added, and the mixture is hydro-kneaded to give a kneaded material, and the mixture of (1) and (2 The porous filter medium obtained by kneading the kneaded product of 1), shaping it into a desired shape, and then placing it in a steam chamber heated to 63 ° C. ± 3 ° C. and curing and aging for 12 to 24 hours.