JPS6220880B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a rotating disk water treatment device which is a biological catalytic oxidation device for treating river water with low substrate concentration by modifying an existing water tank.

Rotating disk water treatment devices have recently been recognized to be extremely effective in treating low-concentration substrates such as river water, and are increasingly being adopted for purification of agricultural water and pretreatment of water supplies.

According to the results of an agricultural water purification experiment conducted using the rotating disk method in the Shin'an Land Improvement District, Osaka Prefecture,
Regarding the shape of the rotating disk, a flat disk has better nitrification efficiency than a corrugated disk, and the circumferential speed of the disk is 27 m/min, which is faster than the 18 m/min normally used for rotating disks. It has been confirmed that the nitrification efficiency for ammonia nitrogen is improved when the temperature is about min.

In addition, this rotating disk method is beginning to be adopted in water supply systems as a pre-treatment device with the main purpose of nitrifying ammonia nitrogen and removing odors, etc., but in many cases, existing water treatment plants are being remodeled. It is expected that.

On the other hand, in the United States, an existing sewage treatment plant where urban sewage was first treated only in a sedimentation tank before being discharged was improved by using a two-stage sedimentation tank as shown in Figure 1.
There is an example in which the upper part is treated with a rotating disk and the lower part is used as a settling tank, and it is said that an average BOD removal rate of 90% is achieved.In this example, a floor plate a is installed in the middle of the existing settling tank, and The upper part is a disk water tank b, and an intermediate partition plate c constitutes a four-stage disk tank, and the sewage treated in the four stages of rotating disks d flows into the lower sedimentation tank e, where The frog settles and the purified water flows out from the edge of the sedimentation tank e.
In addition, this settling tank e is equipped with a sludge scraper f, which scrapes the sludge into the sludge reservoir g, and pumps the sludge pump h.
It is designed to be discharged by

The present invention takes into account the need to improve existing water tanks to treat low-concentration substrate wastewater, and makes effective use of existing water tanks that are deeper and wider than general rotating disk tanks with relatively simple modification. The object of the present invention is to provide a water treatment device that is energy efficient and has high purification efficiency, is more suitable for treating low concentration substrates than other treatment methods.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 4.

FIG. 2 is a longitudinal sectional front view showing an embodiment of the present invention, FIG. 3 is a longitudinal sectional side view thereof, and FIG. 4 is a plan view thereof. In the figure, 1 is an existing rectangular aquarium with a depth of about 5 m, and an inflow channel 2 and an outflow channel 3 are installed near the inner upper surface of both longitudinal walls of this tank in parallel with the side walls. An outflow channel and a disk water tank 4 are formed.

Near the water surface in the disk tank 4, two disk bodies 5a and 5b, which are composed of a large number of parallel thin disks arranged in parallel at right angles to the main axis with an interval of about 20 mm, are placed in the tank. The two disc bodies 5a, 5a, are placed in parallel in a direction perpendicular to the longitudinal direction so that their main axes are parallel to the longitudinal direction, and the immersion rate of the discs is about 40%, which is standard for discs. A partition plate 6 having an opening at the lower part is provided between the partition plates 5b to constitute a two-stage rotating disk device for the flow perpendicular to the axis.

When the rotating disk bodies 5a and 5b are arranged in this way, since the existing water tank 1 is often as long as several tens of meters in the longitudinal direction, the two-stage type shown in FIGS. 3 and 4 is used. A plurality of rows of rotating disk bodies 5a and 5b can be arranged in parallel. With this configuration, the water flowing into the disc water tank 4 from the inflow channel 2 is acted on by the rotating disc body 5a, and then passes through the lower part of the partition plate 6 and enters the next tank. , is purified by the action of the rotating disc body 5b, and is led to the next processing device through the outflow waterway 3. In this way, the present invention configures a two-stage rotating disk device for multiple rows of flow perpendicular to the axis, thereby making possible a pretreatment device for clean water that can treat a large amount of water.

However, like the example in the United States shown in FIG. 1, the existing water tank 1 is often deeper than the standard disk tank, about 5 m deep, so if the above arrangement is used, the rotating disk body 5a There is a considerable gap between 5b and the bottom of the water tank, and there is a risk that the water in this area will stagnate and that sludge separated from the rotating disk will accumulate there and become anaerobic.

In order to avoid such a situation, in the present invention, two rotating disk bodies 5a and 5b are used.
Each of the rectangular disc water tanks 4 is divided into two stages by a partition plate 6 provided between them, and a plurality of fixed shafts 7 are supported by support stands provided at the bottom of the tank. A rotating shaft 10 is provided with a plurality of idling rollers 8 that rotate freely around the aquarium, is supported by a plurality of bearing stands 9 provided on one bottom surface of the aquarium, and spans the two-stage disc aquarium 4. A plurality of rotating rollers 11 and driving wheels 12 are attached to the
It is configured to be rotated by a drive motor 14 via a drive chain 13.

A belt 15 as shown in FIG. 2 and FIG. , two rows of belt conveyors are formed for each stage in the longitudinal direction of the aquarium, and a large number of plate blades 16 made of flat plates or curved plates are attached across the two belts 15, and the drive motors 14 and A belt conveyor type stirrer is installed at the bottom of each stage of the disc water tank 4 so as to be driven by a drive chain 13.

When the rotating disk is in operation, the stirrer is rotated in a direction perpendicular to the rotation of the disk at a speed comparable to the circumferential speed of the rotating disk.

In this way, the sewage at the bottom of the disc water tank 4 is agitated to prevent stagnation of the sewage, and at the same time, it is possible to make the attachment of microorganisms to the surface of the rotating disc active and the aeration effect, and the periphery of the rotating disc Change the speed to the standard circumferential speed.
It is possible to obtain the same purification effect as increasing the speed by 1.5 times to 27m/min.

In this way, the present invention can prevent an increase in driving power caused by increasing the rotation of the rotary disk, resulting in an energy-saving device, and it is possible to improve the nitrification efficiency as a whole. Furthermore, compared to other treatment methods such as honeycomb catalytic oxidation, which involves blowing in air to aerate, even greater energy-saving effects can be expected.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a conventional rotating disk device using an existing sedimentation tank, FIG. 2 is a longitudinal sectional front view showing an embodiment of the rotating disk device according to the present invention, and FIG. 3 is a longitudinal sectional side view thereof. Figure 4 is a plan view thereof. 1... Existing rectangular water tank, 2... Inflow waterway, 3... Outflow waterway, 4... Disc water tank, 5a... Rotating disc body, 5b...
Rotating disk body, 6... Partition plate, 7... Fixed shaft, 8... Idle roller, 9... Bearing stand, 10... Rotating shaft, 11... Rotating roller, 12... Drive wheel, 13... Drive chain, 14... Drive Motor, 15...belt, 16...plate blade.

Claims (1)

[Claims] 1. In a biological catalytic oxidation system for treating river water with low substrate concentration by modifying an existing water tank, an inflow channel and an outflow channel are provided inside both longitudinal walls of the tank to form a rotating disk tank, and parallel A large number of thin disks are arranged in parallel at right angles to the main axis at intervals of about 20 mm.
The rotating disks of the stand are arranged with their main axes parallel to the longitudinal direction of the water tank, and the immersion rate is determined.
40%, and a partition plate with an opening at the bottom is installed between the two disc bodies to create a two-stage disc device for flow perpendicular to the axis, and this can be installed along the longitudinal axis of the existing water tank. A conveyor-type stirrer is installed at the bottom of each stage of the disk group in the disk water tank, which is arranged in multiple rows in parallel in the same direction as the circumferential speed of the rotating disk. A rotating disk water treatment device characterized by rotating at a certain speed.