JPS59115787A - Oxidation basin type waste water treating device - Google Patents

Abstract

PURPOSE:To develop a device which can deal substantially with a fluctuation in load for a long time by disposing base material units packed therein with reticular contact base material groups at a specific ratio in specific positions in oxidation basins in an oxidation basin type waste water treating device packed therein with the net-like contact base materials. CONSTITUTION:An oxidation basin type waste water treating device is constituted of three oxidation basins 1a, 1b, 1c, in which rotors 2a, 2b are respectively disposed. The waste water from the 1st diversion tank 3 is forcibly circulated in the oxidation basin by the rotors 2a, 2b and is thus aerated; at the same time, the sewage from each oxidation basin is fed to the 2nd diversion tank 5. Base body units 8 packed therein with reticular contact base material groups are disposed respectively in different positions in the basins 1a, 1b, 1c, and the packing rate of the reticular contact base material groups is kept within the range of 10-30% as expressed by the equation (1). The satisfactory cleaning treatment is accomplished irrespectively of the fluctuation in load for a long period such as between weeks or seasons.

Description

[Detailed description of the invention] The present invention relates to an oxidized surface type wastewater treatment device.

More specifically, the present invention relates to an oxidized surface type wastewater treatment device filled with a reticulated contact base material.

Traditionally, oxidized oil was used in general wastewater treatment. This method uses paddle or rotor aeration to forcefully circulate pond water and perform biological purification using the action of bacteria and algae. It is something that is done;
Generally, Airley 717 hours are weighed over 24 hours, MLS
S is 3000-5000mg/pXB 01) Load or 0
．． +15~+1.06Kg/Kg 1Lss/day,
It is carried out under treatment conditions such that the return sludge ratio is 50 to 150%, and its advantages include easy operation management and a small amount of surplus sludge, as well as being suitable even when load fluctuations are large. has been pointed out.

However, although it is able to adequately cope with load fluctuations over a short period of time, such as one day, it has the disadvantage that it cannot adequately cope with load fluctuations over a long period of time, such as a week or between seasons. there were.

In other words, when relatively large load fluctuations occur over a long period of time, suspended solids disintegrate and do not settle when the load becomes low, resulting in a significant drop in processing capacity when the load changes from low to high. The problem was that it could not be adequately addressed.

The present invention was invented in view of these conventional drawbacks, and its purpose is not only to deal with load fluctuations over a short period of time such as one day, but also to deal with load fluctuations over a week or season. An object of the present invention is to provide an oxidation pond wastewater treatment device that can sufficiently cope with load fluctuations over a long period of time and can always perform a good purification treatment P1.

The oxidation pond tank wastewater treatment apparatus according to the present invention which achieves this objective is to fill an oxidation pond with a network contact base material group approximately at I/fj with respect to the circulating water flow, and to fill the oxidation pond with a filling rate (X ) is 10Φ to 30%.

Pv Mv: Apparent total filling volume of the reticulated contact base material group Pv: Total volume of the oxidation pond (m') The present invention will be specifically described below based on Examples.
In Figure 1, oxidation ponds (1a, l l
), l c ) have rotors (2a, 2b), respectively.
) are installed, and the wastewater supplied to various places from the first water division tank (3) is forcibly circulated in the direction of the arrow in the figure by these rotors (2a, 2+)), and a pump is installed. (4) so that wastewater can be sent from various places to the second water division tank (5).

Note that each region (]a, ]l), lc) is filled with the reticular contact base material FIT so that the filling positions thereof are different from each other while keeping the filling rate determined as described later the same.

That is, in the oxidation pond (Ia), as shown in FIG. ) The side straight waterway (A) is filled with a set and the rotor (2+)) The side curved waterway (B) is filled with two sets. In addition, in the oxidation pond (lb), two sets of water are filled in the straight waterway (A) on the rotor (2a) side, and three sets are filled in the straight waterway (B) on the rotor (2b) side.
has been done.

Furthermore, in the oxidation pond (1c), the corner waterway ('C
), (D) are filled with 1 cent each, and one set is filled in the straight waterway (Δ) on the rotor (2a) side, and the rotor (
21)) Two cents are filled in the side line waterway (,B). These ponds (]a, ]l).

], Is the base material unit (8) filled in C) so as to be submerged in water, and is it a reticulated contact base material (];)? J
It is filled almost parallel to the A ring water flow, and the filling rate at each location (]a, lb, lc) is 10% to 3
The filling rate here is the ratio of the total volume of the oxidation pond to the total apparent filling volume of the reticulated contact base material t[[P]. is expressed as a percentage; an example is an oxidation pond (1a)
Let the total volume of the pond (1a) be Pv (m'), and the apparent total volume of the network contact base material (6) filled in this pond (1a) be M
v (m″), its filling rate (X) is 100 M
v/Pv, and Mv is shown in Fig. 2 (
The apparent filling volume (mV) per base unit (8) obtained by multiplying the dimensions of g+), (/2), and (1:3) by the number of filling cents (n) for the base unit (8). That is, in this example, it is obtained by multiplying n=5 by B1.

The present invention thus provides an oxidation pond (I a , 11),
It is essential to fill the reticulated contact base material (() in order to obtain a filling rate in the range of 10% to ;) 0% for l c ). The biofilm can always be adhered to the base material (11), and the biofilm or suspended sludge in the conventional method (
Unlike MLSS), it has a property of high cohesiveness and does not disintegrate, so it can sufficiently cope with large negative masonry fluctuations and can perform stable processing.

In other words, the sewage that has been treated in the oxidation ponds (LA, LB, LC) and sent to the second diversion tank (5) via the pump (4) is sent from here to the settling tank (!1) to remove the excess biofilm system. The sludge is well separated and then this pre-sludge is sent to the oxidation pond (la, 1
The sludge is returned to b, lc) and turned into suspended sludge, but by mixing this sludge with the biofilm sludge in the pond, relatively thick sludge with settling properties can be obtained even under low load conditions. Therefore, it is possible to perform stable processing even with large load fluctuations3.It should be noted that it is possible to perform stable processing even with large load fluctuations. 1. The effects of the present invention as described above cannot be obtained because a sufficient biofilm cannot be deposited even if the method is used.

In the present invention, it is preferable to fill the reticulated contact base material so that it is parallel to the circulating water flow in the pond.If it is not filled in this way, the circulating flow rate by the rotor (2; 1, 21) will be reduced and the biological The contact between the membrane and the wastewater becomes poor, the supply of dissolved oxygen becomes insufficient, and the returned sludge settles in the pond without becoming suspended sludge, making it difficult to perform good treatment. Become. The filling position is the corner waterway (C, l) like the oxidation pond (1c).
It is preferable to fill only the straight water channels (A, B) like the oxidation pond (la, 11)) rather than filling the straight channels (A, B).

Further, if the filling rate (X) is set in a range other than 10% to 30%, it will be difficult to perform good processing. That is, when the amount is less than 10%, a sufficient amount of biofilm cannot be obtained, and when it is more than 30%, the circulation flow rate decreases significantly, making it difficult to perform good treatment. Straight waterway (A.

B) and the course waterway (C, I)) with the base material unit (
8) Circulating artificial sewage in the oxidation pond (1c) filled with water at a flow rate (v) or I), i m/s to 2 m/s, during air conditioning ("water retention time") or 24 hours, Motori Uninot
l) The fixed width (■) of the synthetic resin reticulated contact base material (6) in t) is 5 (l tnm ~ 200 mrn
-, the mesh size of the base is 5ir+m~2
0mm, the wire diameter is 1mm~3m+n, and the load is 1mm.

On Tuesday, Wednesday, and Thursday each 11Fj] Omg/e,
In case of repeated treatment, such as 30 mg/p on Friday, 50 mg/p on Saturday, 11M, Sunday and Sunday, the filling rate (X)
The relationship between water and treated water is shown in Table 1.

Table 1 Also, from the oxidation pond (1c), when all of the sl was removed and the same type of water was treated at the same υ (11 reflux rate, air lane time, and load fluctuation, the treated water quality was) (l mg/p to 25 mg/p.

As is clear from this, according to the present invention, even if the load rlj varies greatly, it can always be kept below the specified value (20 mg//).

In addition, in order to further confirm that such a drooping effect can be obtained, M L
MLSS 985m can be obtained by naturally settling S S 960 mg/f and concentrating it 10 times, and by mixing the returned suspended sludge with the biofilm sludge in the pond as in the present invention.
A comparative study was conducted with the case of 0 times concentration of g//, and it was found that while the former took about 1 hour, the latter took about 15 minutes. The twisting occurred in about 1/4 of the time compared to the conventional method. Since it is possible to pump more water, it is possible to move from the sedimentation tank (II) to the oxidation tank (la, ]b, lc) in a short cycle.
It is possible to return the separated 〆υ mud tH1 to increase the number of particles, and it is possible to process well not only at low loads but also at high loads, and also to withstand load fluctuations in short and long periods. It can always be processed well regardless of the situation.

In addition, in the present invention, the negative Ais is (1,02Kg/m
' In the case of El~0.06 Kg/+η3・day, the filling rate (X) is set to 15% to 20%, and 0,05
Kg/m1 day - 0.01 Kg/m' day, preferably 20% to 30%.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an oxidation pond type wastewater treatment apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view of a base material unit (8). (la, lb, lc): Oxidation pond (6): Reticular contact base material patent applicant Toshi Engineering Link Co., Ltd. Figure 1

Claims (1)

[Claims] f+) A group of reticular contact substrates is filled in the M conversion pond approximately parallel to the circulating water flow, and the filling rate ('
) is 1()% to 30%, Pv Mv: Apparent total filling volume (m') of the network contact base material group Pv:
Total volume of oxidation pond (1)