JP2002101871A - Pellet containing humic matter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide pellets suitable for circulating in a reservoir for cultivating soil bacteria. SOLUTION: This pellet 22 is usable in a reservoir for cultivating soil bacteria, contains humic matter and has almost spherical shape and 0.98-1.2 apparent specific gravity.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a pellet used for culturing soil bacteria in a process for treating organic wastewater.

[0002]

2. Description of the Related Art A simple apparatus for producing seed sludge disclosed in Japanese Patent Publication No. 5-10999 has a water storage tank and a cylindrical body accommodated therein. The cylindrical body is filled with a microorganism metabolic circuit inducer, and the organic wastewater guided to the water tank circulates inside the water tank by the action of air that is blown out as bubbles from the air diffuser.
The organic wastewater circulates while passing between the inducers, and microorganisms are cultured during the circulation. This inducer is obtained by processing a mixture of humic substances and andesite, rhyolite, pumice, and the like, has a columnar or disk shape, and is generally called a pellet.

[0003]

The pellets used in the above-mentioned conventional apparatus only slightly move inside the water storage tank by the action of the circulating drainage and the air from the air diffuser, so that the apparatus is continuously operated. The wear of the pellets is relatively small even if the operation is performed at a low speed. However, unlike such conventional devices, the conventional pellets used in a device of a type that circulates pellets in a water storage tank have an apparent specific gravity of 1.3 to 1.3.
It is about 1.5 and heavy, and the shape is columnar or disk-shaped, so it is difficult to circulate the pellets unless the bubbles are violently blown out from the air diffuser.At that time, the pellets collide violently and the pellets wear out. early.

[0004] Therefore, the present invention is to improve the pellets used in the process of treating organic waste water so that they can be easily circulated in the water storage tank and are not easily worn during circulation. Is an issue.

[0005]

In order to solve the above problems,
The present invention is directed to pellets containing humic substances that can be used for culturing soil bacteria in a water tank provided in a process for treating organic wastewater. In such a pellet, the present invention is characterized in that the shape of the pellet is substantially spherical and the apparent specific gravity is 0.9.
In the range of 8 to 1.2.

In one preferred embodiment of the present invention, the ratio A: B of the length A to the height B of the pellet and the ratio A: C of the length A to the width C are all 1: 0. .7-
1: 1.3.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the pellets according to the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view of an apparatus 1 for showing a state in which a pellet 22 according to the present invention is used in a seed sludge production apparatus 1 as an example of a wastewater treatment apparatus. Apparatus 1
Has a water storage tank 2 and a pellet guide tube 3. The water storage tank 2 has, for example, a cylindrical shape, and has an inflow port 4 for introducing agricultural settlement drainage and intermediate treatment water from the drainage treatment system at the top, and solids and tanks in the water storage tank 2 at the bottom. It has an outlet 6 from which the wastewater treated inside can be taken out. Between the inflow port 4 and the discharge port 6, an outflow port 7 for guiding the wastewater treated in the water storage tank 2 to an external wastewater treatment system is provided. The top of the water storage tank 2 is covered with a lid 9 having an inspection port 8.

The guide pipe 3 is a double pipe disposed inside the water storage tank 2 and comprises an inner cylinder 11 and an outer cylinder 12, and the inner and outer cylinders 11 and 12 are provided with water through a support rod 13 extending horizontally. It is fixed to the tank 2. The inner cylinder 11 has a top 11a and a bottom 1
1b is in an open state, and an air supply pipe 14 extending from the outside of the water storage tank 2 is located between the top 11a and the bottom 11b near the bottom 11b. The outer cylinder 12 also has a top part 12a and a bottom part 12b in an open state.
Numerous water-permeable through holes 18 communicating with the inside and outside of the outer cylinder 12 are formed in 2a and 12b. The diameter of the through hole 18 is smaller than the diameter of the pellet 22.

In the height direction of the water storage tank 2, the top 12 a of the outer cylinder 12 is located slightly above the top 11 a of the inner cylinder 11. The bottom 21 of the water storage tank 2 is preferably inclined such that the central portion is lowest, as shown. The bottom 11b of the inner cylinder 11 and the bottom 12b of the outer cylinder 12 are located above the bottom 21 of the water storage tank 2, and preferably the bottom 11b of the inner cylinder 11 is located below the bottom 12b of the outer cylinder 12. ing.

In such an apparatus 1, the drainage W is supplied from the inflow port 4 to a position where the water surface S is located between the tops 11 a and 12 a of the inner and outer cylinders 11 and 12. Further, a required amount of pellets 22 containing humic substances capable of cultivating and activating soil bacteria useful for wastewater treatment are charged into the inner and outer cylinders 11 and 12. In addition, particles such as second pellets or pumice, which are made of only inorganic substances and do not contain humic substances, may be added together with the pellets 22. Pressurized air is continuously supplied from the outside of the water storage tank 2 to the inside of the inner cylinder 11 through the air supply pipe 14, and the pellet 22 moves up the inner cylinder 11 together with the drainage W by the air, and is discharged from the top 11 a. It enters the cylinder 12. Pellets 22
Is the drainage W which rises up the inner cylinder 11 and overflows from the top 11a.
Down the outer cylinder 12 following the flow of
The inner cylinder 11 is moved up again from the bottom 11b of the inner cylinder 11.

When the apparatus 1 is operated in this manner, the pellets 22 are separated from each other and come into contact with the waste water W in the water storage tank 2 and the air from the air supply pipe 14, and this waste water W Can promote the cultivation and activation of soil bacteria. In addition, since each of the pellets 22 is circulated and consumed in substantially the same manner, if a small amount of the pellets 22 are collected from the inspection port 8 during the operation of the apparatus 1 and inspected,
The wear state of the entire pellet 22 can be grasped.
When the air supply from the air supply pipe 14 is stopped, the pellets 22 having a large specific gravity collect on the inclined bottom portion 21 of the water storage tank 2 and can be easily collected from the discharge port 6. The pellet 22 having a low specific gravity can be collected by opening the lid 9. The required amount of wastewater W treated by the apparatus 1 can be taken out from the outlet 7 as seed sludge. The drainage W can be taken out from the outlet 6 if necessary.

FIG. 2 is a perspective view of the pellet 22. The shape of the pellet 22 is preferably a sphere or an ellipsoid or a polyhedron close to a sphere, so that the pellet 22 can smoothly circulate without vibrating inside the guide tube 3, and the length A is 7 to 30 mm. And the length A
Ratio A: B between the height A and the height B and ratio A: C between the length A and the width C.
Are preferably in the range of 1: 0.7 to 1: 1.3. It is preferable that the apparent specific gravity of the pellet 22 is adjusted in the range of 0.98 to 1.2 so that the pellet 22 is easily circulated together with the wastewater W. The pellet 22
The compressive strength after immersion for 24 hours is at least 3.2 kg (3
(1.4N), the degree of wear is small even if they collide with each other during circulation or collide with the inner cylinder 11 or the outer cylinder 12. Such compressive strength is the maximum pressure when the pellet 22 is compressed by the compression tester.

In order to obtain such pellets 22, 20 to 80% by weight of humic substances and 80 to 20% by weight of mineral particles such as pumice, zeolite, diatomaceous earth and clay mineral are mixed, and more preferably, the mixture is mixed with iron. 5 metal powders such as powder and aluminum powder
% By weight, or sodium alginate or cellulose powder to 10% by weight. These components are mixed, and if necessary, an appropriate amount of water is added and mixed. Then, using a granulating means such as a mold, the length A, height B, and width C satisfy the above-mentioned values. 2-3 after molding into
Air dry naturally and heat to 200-400 ° C. Humic substances are essential components for cultivating and activating soil bacteria in the device 1. Pumice, zeolite, diatomaceous earth and clay minerals are used together with humic substances to help cultivate and activate soil bacteria,
2 is useful in adjusting the strength and specific gravity.
Iron powder, aluminum powder, and cellulose are useful for improving the strength of the pellets 22, although their action mechanism is not clear. When a water-soluble binder such as sodium alginate is used, it becomes easy to mix the respective components and preliminarily form particles.

Table 1 shows an example of the compressive strength of the thus obtained spherical pellet 22 having a diameter of about 20 mm in comparison with the compressive strength of a pellet consisting only of humic substances and pumice. . The compression strength of the pellets is improved by mixing iron powder and the like.

[0016]

[Table 1]

[0017]

Since the pellet according to the present invention is a sphere or a sphere, it can be smoothly circulated in the water storage tank provided in the wastewater treatment step without violent shaking. The pellets are 0.9
It has an apparent specific gravity of 8 to 1.2 and circulates easily along the drainage stream. Furthermore, 24 of the pellets
Since the compressive strength after water absorption for a long time is high,
The risk of wear due to collisions with each other during circulation is reduced.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a wastewater treatment apparatus showing a use state of pellets.

FIG. 2 is a perspective view of a pellet.

[Explanation of symbols]

 22 Pellets A Length B Height C Width

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C02F 3/10 ZAB C02F 3/10 ZABA 3/34 3/34 Z // C12M 1/00 C12M 1/00 HF term (reference) 4B029 AA02 AA27 BB02 CC01 CC02 DA04 DB12 DC07 DF10 DG06 4B065 AA01X BB22 BB40 BC41 BC47 CA55 4D003 AA14 AB03 EA14 EA21 EA22 EA23 EA26 EA28 EA38 4D040 DD03 DD31

Claims (5)

[Claims] 1. A pellet containing humic substances that can be used for culturing soil bacteria in a water storage tank provided in a process of treating organic waste water, wherein the pellet has a substantially spherical shape and an apparent shape. Wherein the specific gravity is in the range of 0.98 to 1.2. 2. The ratio A: B of the length A to the height B of the pellets is 1: 0.7 to 1: 1.3, and the ratio A: C of the length A to the width C is 1: 0. 0.7-1: 1.3.
The pellet as described. 3. The pellet according to claim 1, wherein the pellet has a compressive strength after immersion in water for 24 hours of at least 3.2 kg (31.4 N). 4. The pellet according to claim 1, which contains at least one of iron powder and aluminum powder up to 5% by weight. 5. The pellet according to claim 1, further comprising a water-soluble binder.