JPS5815038B2 - Sewage treatment equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for treating wastewater based on a rotary biological contact method.

Wastewater treatment using the rotary biological contact method has the advantage that it has a large treatment capacity because it holds a large amount of microorganisms per unit volume, and that both anaerobic and aerobic treatments can be performed using only rotary power.

This invention utilizes the advantages of the rotary biological contact method as described above to provide a wastewater treatment device that can efficiently reduce the molecular weight of organic matter contained in wastewater, remove organic matter, and denitrify it. is intended to provide.

Next, an embodiment of the present invention will be described with reference to the drawings.

The sewage treatment apparatus shown in FIG. 1 has two tanks 1 and 2 arranged adjacent to each other.

One tank 1 is of a closed type, and inside thereof there are three anaerobic treatment chambers 1a and 1b separated by partition walls.

It is divided into 1c, and a rotating contact body 3 is arranged in each chamber.

This rotary contact body 3 includes each anaerobic treatment chamber la, 1b, and Ic.
It is connected to a drive source (not shown) so as to rotate in the direction of the arrow in FIG. 1 below the liquid level inside.

The other tank 2 is an open type having three aerobic treatment chambers 2 a t 2 b and 2 c separated by a partition wall, and each aerobic treatment chamber 2 a y 2 by 20 includes:
A rotating contact body 4 that rotates in the direction of the arrow while receiving power from a drive source (not shown) with a part of its peripheral surface exposed in the air.
is provided.

The planar arrangement of each anaerobic treatment chamber 1a, 1b, 1c and each aerobic treatment chamber 2a, 2b, '2c and the movement of liquid between each chamber are shown in the flow sheet of FIG.

The inflowing wastewater to be treated is first introduced into the anaerobic treatment chamber 1a, where the organic matter in the wastewater is reduced in molecular weight, and then flows into the aerobic treatment chamber 2a as an overflow.

In this aerobic treatment chamber 2a, organic matter is removed under aerobic conditions, and then transferred to the adjacent aerobic treatment chamber 2b, where it undergoes nitrification, and then continues through the anaerobic treatment chamber 1b. It flows into the anaerobic treatment chamber 1c.

The anaerobic processing chambers 1b and 1c perform denitrification processing on the supplied liquid under anaerobic conditions.

Here, part of the wastewater that has been reduced in molecular weight in the anaerobic treatment chamber 1a is flowed into the anaerobic treatment chambers 1b and 1c, and the liquid in the anaerobic treatment chamber 1a is used as a hydrogen donor necessary for the denitrification treatment. It is possible to make use of the low-molecular-weight organic substances contained in the fibers, and for this purpose a thread path (not shown) with a pump is provided.

In addition, the liquid that has undergone denitrification treatment in the anaerobic treatment chamber 1c overflows and moves to the aerobic treatment chamber 2C, where it is aerated again and then sent to the sedimentation tank 5 and then to each anaerobic treatment tank. 1a, 1b, Ic and each aerobic treatment tank 2a
, 2b t 2 c is carried out mainly by the action of microorganisms in biofilms attached to the surfaces of the rotating contact bodies 3 and 4 rotating inside each of them.

The settling tank 5 is for settling the sludge contained in the liquid received from the aerobic treatment chamber 2c, and the settled sludge is discharged as surplus sludge, and the supernatant liquid flows out as treated water.

A part of the treated water is also returned to the aerobic treatment chamber 2b.

Alternatively, instead of returning the treated water, a portion of the liquid that has left the aerobic treatment chamber 2c may be returned.

In other words, the sewage treatment equipment shown in Figures 1 and 2 is
Anaerobic treatment chambers 1a, 1b, 1c and aerobic treatment chamber 2a
, 2b and 2c, biological treatment as shown in FIG. 3 is performed by the action of microorganisms contained in the biological layer on the surfaces of the rotary contact bodies 3 and 4 rotating in each chamber.

Since the substrate in the inflow water is reduced in molecular weight in the first step, organic matter can be efficiently removed in subsequent treatments.

Moreover, since denitrification is also performed following the removal of organic matter, a more advanced treatment can be achieved.

Since these biological treatments are carried out according to the rotary biological contact method, denitrification and other treatments are inhibited by the presence of some dissolved oxygen in the liquid contained in each anaerobic treatment chamber. Since the amount of microorganisms retained in the biofilm is large, there is no need to return the sludge.

Furthermore, tank 1 in which an anaerobic treatment chamber is formed and tank 2 in which an aerobic treatment chamber is formed are provided adjacent to each other, and rotary contact bodies 3 and 4 are provided separately for each type 1 and 2, so that stirring This eliminates the need for a machine, significantly simplifies piping, and enables a compact configuration suitable for small-scale treatment plants, and consumes less energy as a power source.

In the above embodiment, two anaerobic treatment chambers 2b and 2c were provided to perform denitrification treatment in two stages, but one of them may be omitted depending on the nature of the inflowing wastewater. It is also possible to do the above.

Also, the aerobic treatment chambers 2a and 2b can be made into a single chamber so that organic matter removal and nitrification are carried out in the same chamber, and the aerobic treatment chamber 2c for re-aeration can sometimes be omitted.

[Brief explanation of drawings]

FIG. 1 is a perspective view of a sewage treatment device according to an embodiment of the present invention, FIG. 2 is an explanatory diagram showing a fluid flow in the device in plan, and FIG. 3 is a diagram showing biological treatment in the device. This is a flow sheet showing the process. 1.2...tank, 1 a t 1 b, 1 c
...Anaerobic treatment room, 2a, 2b, 2c...
...Aerobic treatment chamber, 3゜4...Rotating contact body, 5
...Sedimentation pond.

Claims (1)

[Claims] 1. A first tank forming a plurality of anaerobic processing chambers, a first rotating contact body located in each anaerobic tank, and at least one aerobic processing chamber adjacent to the first tank. Second to do
The inflow wastewater is introduced into one of the anaerobic treatment chambers, which is agitated by the tank, the second rotary contact body located in the aerobic treatment chamber, and the first rotary contact body, and the low molecular weight substrate is removed. The sewage from the low molecular weight process is then led to the aerobic treatment chamber for organic matter removal and nitrification, and then to another of the anaerobic treatment chambers for denitrification. A sewage treatment device comprising a liquid transfer means for causing a part of the liquid to flow into the denitrification process.