JPH0214120B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement on the so-called oxidation date that uses a conventional annular water groove, and is a biological treatment device that removes phosphorus contained in water as well as BOD components with a simple device. Regarding.

Recently, treatment equipment called oxidation date has been reviewed as a method of sewage treatment equipment for small-scale treatment plants.

This treatment equipment has been used for a long time, and it forms an annular water groove with a retention volume of 24 hours for the water from which BOD components are to be removed. At the same time, the water to be treated flows in from the water groove, and a rotor or the like is rotated at one or two places in the water groove to dissolve air in the water and give a water flow to the water groove, and the treated water is introduced from other points in the water groove. It is something that is made to flow out. In this way, when the water to be treated is supplied to the water groove and the water in the water groove is circulated, the BOD components in the water to be treated are oxidized and decomposed by aerobic microorganisms, and the BOD component is removed. You can get water.

Further, the treated water is then treated in a sludge sedimentation separation tank to remove sludge from the treated water, disinfected, and then released.

Oxidation daters process a large amount of water to be treated by flowing it into a water groove with a relatively large capacity and circulating it, so it is resistant to fluctuations in flow rate and BOD load, does not cause bulking, and is particularly effective. It does not require sophisticated operation management, the structure of the device is simple, and the construction cost is low, making it suitable for small-scale sewage treatment.

On the other hand, in recent years, eutrophication in closed water systems such as lakes and marshes has become a problem, and the necessity of removing phosphorus along with BOD components has been discussed. Can not.

The present invention cleverly combines the principle that when activated sludge is cultured under anaerobic and then aerobic conditions, a type of sludge that accumulates excessive phosphorus will proliferate, and oxidation date. with equipment
The purpose is to provide a device that removes BOD components and phosphorus. That is, the present invention consists of a six-shaped water groove in which one end of an annular inflow groove that is an anaerobic zone is connected to an annular water groove that is an aerobic zone, and a sludge sedimentation tank. The return sludge and water to be treated from the sedimentation separation tank flow in from the other end and are first treated with anaerobic microorganisms, then the water to be treated is circulated through the annular water groove to be treated with aerobic microorganisms, and then circulated. 6-shaped water, characterized in that treated water of the same volume as the amount of water flowing into the inflow water groove is taken out from the annular water groove, and the sludge in the treated water is subjected to solid-liquid separation in the sludge sedimentation separation tank. This invention relates to a biological treatment device using grooves.

The present invention will be explained in detail below with reference to the drawings.

The drawing is a plan explanatory diagram of a flow that is an example of an embodiment of the present invention, and this device has an annular water groove 1 that maintains an aerobic zone A and a non-annular inflow groove 2 that maintains an anaerobic zone B.
6-shaped water groove connected to the sludge sedimentation separation tank 3
Consisting of In the annular water groove 1, a rotor 4 whose rotational axis intersects at right angles to the water flow is placed downstream from the connection part with the inflow water groove 2, for example, by rotating it half submerged in the water surface to allow circulation to flow through the annular water groove 1. Air is dissolved in the flowing water to maintain aerobic properties, and a water flow shown by the arrow is provided in the annular water groove 1. Further, one end of the annular water groove 1 and the sedimentation separation tank 3 are connected through a treated water take-out pipe 5, and the sludge separated in the sedimentation separation tank 3 is mixed into the treated water inflow pipe 7 via the return sludge pipe 6. do. Note that a blow pipe 8 for excess sludge is branched and connected to the return sludge pipe 6. Further, as mentioned above, the inflow water groove 2 is to maintain anaerobic properties, and the degree of anaerobic properties must be at least 0.1ppmas0 or less in terms of dissolved oxygen. For this purpose, it is better to completely seal the upper part of the inflow water groove 2 and isolate it from the outside air. In addition, a stirrer (not shown) is used to thoroughly mix the water to be treated and the returned sludge.
is installed in the inflow water groove 2.

Note that the annular water groove 1 and the inflow water groove 2 may be made of above ground tanks made of steel plates, concrete, etc., or may be semi-underground or underground tanks.

Next, to explain the treatment method of the apparatus of the present invention, first, water to be treated flows in from the tip of the inflow water groove 2 from the water inflow pipe 7, and the sludge separated by the sedimentation separation tank 3 is sent to the return sludge pipe 6, The treated water flows in the form of a slurry through the inflow pipe 7 from the tip of the inflow groove. These treated water and returned sludge become a mixture and flow through anaerobic zone B as shown by the arrow, but in this anaerobic zone B, the BOD in the treated water
Some of the components are taken into the sludge, and the phosphorus accumulated in the sludge is released, and the phosphorus concentration in the water in the anaerobic zone B temporarily increases.

The water to be treated then reaches one end of the annular water groove 1, where it joins the water system that circulates through the annular water groove 1 and is subjected to aerobic treatment. While circulating through this aerobic zone A, the BOD components taken into the sludge and the BOD components in the water are oxidized and decomposed, and the phosphorus in the water is taken into the sludge.

In addition, the amount of water flowing into the inflow water groove 2 from the treated water inflow pipe 7 via the treated water take-out pipe 5 from the other end of the annular water groove 1 which is circulating, that is, the total amount of water to be treated and the returned sludge. The same amount of treated water is taken out, the sludge in the treated water is separated by the sedimentation separation tank 3, and the supernatant water is sterilized and discharged. On the other hand, a sludge pipe 6 returns settled sludge to the lower part of the sedimentation separation tank 3.
The water to be treated is circulated through the inflow pipe 7, and at this time, excess sludge is blown through the blow pipe 8. As mentioned above, this surplus sludge contains a large amount of phosphorus, and by blowing out the surplus sludge, the mass balance of the system can be maintained.

As explained above, the present invention can remove BOD components and phosphorus from water to be treated with a device of simple structure, is resistant to flow rate fluctuations and BOD load fluctuations, does not cause bulking, and has a particularly high level of Since it does not require operation management, it is suitable for small-scale sewage treatment.

Examples of the present invention will be described below.

Example As shown in the drawing, the waterway width is 20cm, the water depth is 40cm,
An annular water groove with a capacity of 60 cm, the same waterway and water depth, and the same capacity.
We fabricated an experimental device consisting of a 6-shaped water groove connecting 20 inflow water grooves and a sludge sedimentation separation tank, and installed an agitator with a propeller diameter of 5 cm in the inflow water groove.
A Kessner type rotor with a rotor diameter of 6 cm was installed downstream from the connection between the annular water groove and the inflow water groove.
The upper part of the inflow water groove was sealed and isolated from the outside air.

Using such an experimental device, an average BOD of 150mgasO/, an average PO ₄ -P4 from the tip of the inflow water groove was obtained.
mg/, PH6.9, water temperature 18℃ water to be treated 10/H
At the same time, the sludge returned from the sedimentation separation tank was flowed in so that the average MLSS concentration in the annular water groove and the inflow water groove was 2400 mg/H, and the sludge was processed while driving the agitator and rotor. .

As a result, the treated water became stable after about one month of treatment.
BOD of treated water at the outlet of the inflow water channel is 25mg/,
The BOD in the supernatant water of the sedimentation separation tank is 12 mg/
In addition, PO ₄ -P temporarily increased to 35 mg/in the inflow water groove, but decreased to 0.4 mg/in the supernatant water of the settling tank.

[Brief explanation of drawings]

The drawing is a plan explanatory diagram of a flow that is an example of an embodiment of the present invention. 1... Annular water groove, 2... Inflow water groove, 3... Sedimentation separation tank, 4... Rotor, 5... Treated water take-out pipe, 6... Return sludge pipe, 7... Treated water inflow pipe,
8...Blow tube, A...Aerobic zone, B...Anaerobic zone.

Claims (1)

[Claims] 1 Consists of a 6-shaped water groove that connects one end of the aerobic zone (annular water groove) to the anaerobic zone (non-circular inflow groove), and a sludge settling and separation tank, The return sludge obtained in the sedimentation separation tank and the water to be treated flow in and are first treated with anaerobic microorganisms, and then the water to be treated is circulated through the annular water groove to be treated with aerobic microorganisms. A 6-shaped water groove is used, which is characterized in that the same volume of treated water as the amount of water that has flowed into the inflow water groove is taken out from the water groove, and the sludge in the treated water is separated into solid and liquid by the sludge sedimentation separation tank. Biological treatment equipment.