1. Experiment purpose
Before purifying the water of Yodo-castle moat directly on the spot, we conducted a purification experiment in a water tank for the purpose of determining the effects of fine bubbles. Visual observations, camera photographs and microscope observational photographs were used as the methods to determine the purification.
2. Experiment apparatus
Fine bubble generating experiment apparatus was composed from the devices below.
①Loop Flow OK Nozzle : OKE-MB07FJ（20L/min）
②Water tank : 10Ｌ（acrylic transparent）
③Pump : MD70RZM（IWAKI product）
④Gas flow meter : MF-F （HORIBA product）
⑤Manometer : Max0.4MPa ⑥Carrier : Flexible resin needle ball (Φ79)
3. Experiment method
(1) Put approx. 7L of raw water from the moat into the 10L water tank and generate fine bubbles using a loop flow OK Nozzle.
①Water pressure : 0.06MPa
②Air self-intaking amount : 35mL/min
As the water amount was 7L, the condition was lowered.
(2) The fine bubbles were generated for some hours not continuously but with intervals. It was not operated at night time because the water temperature rises a lot when operated for a long time. Operating times are written below.
4. Experiment results (excerpt)
(1) The times of fine bubble generation
(2) Photograph determination
Higher transparency after the fine bubble purification.
①May. 20 (Raw water before FB operation)
②May. 25 (After FB purification)
(3) Microscope photograph
① Raw water (Supernatant in a polyethylene tank) shot on May. 24
(4) Water after the fine bubble purification
① 2017. May. 2４ (First day of stopping FB generation)
② May. 26 (Third day after stopping FB generation)（ＦＢ発生停止３日目）
①As can be seen from the experiment photos of water tank and the microscope photos, contaminations inside the water are removed by generating fine bubbles. This is inferred that the microorganisms in the water were activated by fine bubbles and thus purified the water.
②When we observed the raw water and the purified water by putting them into a 100ml beaker and held it up to the light;
●In the raw water, a lot of small supernatants were seen.
●In the purified water, no contaminations were checked visually.
③After generating fine bubbles until May. 23rd, we observed how the purified water had changed with microscope. Compared to the microscope photos of the 24th and 25th, there were almost no contaminations in the photos taken on the 26th. This is inferred to be a result of the precipitation of the contaminations and the microbial function.
It is presumed that this is due to contamination precipitation and microbial treatment.これはコンタミの沈殿と微生物の処理によるものと推察される。
④From these experiment results, it was proved that the loop flow fine bubble generation OK Nozzle exhibits high effect for purifying moat water of Yodo castle.