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Treatment process of water treatment plants
Last Updated March 29, 2024
The water purification plant is a facility that produces tap water. There are three water purification plants in Yokohama city: Kawai, Nishiya, and Kojaku.
Treatment process of water treatment plants
Nishiya Water Purification Plant and Kosuzume Purifiction Plant use the rapid filtration method as shown in the figure.
On the other hand, Kawai Purification Plant uses the membrane filtration method.
- Rapid filtration method: Contamination in the water is attached with a coagulant, a chemical, to form a large lump and sink to the bottom (aggregated sedimentation). In addition, it is a method of removing small lumps that did not sink by passing the supernatant of the dirty water through the sand filtration pond.
- Membrane filtration method:The Mechanism of Kawai Purification Plant membrane filtrationPlease refer to the following URL.
I arrived at Mizui
Arriving Mizui
Water (raw water) taken from rivers, lakes, etc. is the first place to arrive at the water purification plant. The amount of water is adjusted here and sent to the sinking pond.
Sinking pond
Sinking pond
Inject a flocculant (polyaluminum chloride) into the raw water. The suspended matter in the raw water becomes a large lump (flock) and sinks.
Mechanism of agglomeration and sinking
Rapid filtration pond
Rapid filtration pond
Fine suspended matter that was not removed in the sinking pond is removed through a layer of sand and gravel.
Mechanism of sand filtration
Disinfection Equipment
Disinfection Equipment
Sodium hypochlorite (chlorine) is added to the filtered water to disinfect it, and tap water that can be drunk with confidence is completed.
Effect of chlorination
Reservoir
Reservoir (In the facilities shown in the photo, the basement of the lawn is the reservoir.)
In a warehouse where tap water is stored, the amount of water is adjusted according to the amount of water used. It also secures drinking water in the event of a disaster such as an earthquake.
Pumping Station
Distribution Pumping Station
It is a facility for sending tap water at a certain level of water pressure throughout the undulating city.
Wastewater treatment facilities
Wastewater treatment facilities
Wastewater treatment facilities
Concentrates and dehydrates impurities removed in the sinking pond and filtration pond. This will be used effectively as construction materials.
Inquiries to this page
Water Works Bureau Water Purification Department
Telephone: 045-671-3544
Telephone: 045-671-3544
Fax: 045-212-1158
Email address: su-josui@city.yokohama.lg.jp
Page ID: 869-606-860
