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Treatment process of water treatment plants
Last Updated March 29, 2024
A 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 perform water purification treatment using the "rapid filtration method" as shown in the figure.
Kawai Purification Plant, on the other hand, uses the membrane filtration method.
- Rapid filtration method: The dirt in the water is attached with a flocculant, a chemical, to form a large lump and submerged to the bottom (coagulation sedimentation). In addition, it is a method of removing small clumps that did not sink by passing the supernatant water through a sand filtration pond.
- Membrane filtration method:Kawai Purification Plant membrane filtrationPlease refer to the following URL.
Riku Mizui
Riku Mizui
This is where water (raw water) taken from rivers, lakes, etc. arrives at the water purification plant first. The amount of water is adjusted here and sent to the sinking pond.
Sinking pond
Sinking pond
Agglomerator (poly aluminum chloride) is injected into raw water. Suspended matter in raw water become large lumps (flocks) and sinks.
Mechanisms of aggregation Sinkden
Rapid filtration pond
Rapid filtration pond
Fine suspended matter that has not been removed in the sinking pond are removed through a layer of sand and gravel.
Sand filtering mechanism
Disinfection equipment
Disinfection equipment
Sodium hypochlorite (chlorine) is added to the filtered water and disinfected, and tap water that can be safely drunk.
Effects of Chlorine Treatment
Distribution reservoir
Reservoir (In the facility in the photo, the basement of the lawn is the reservoir.)
In a warehouse that stores tap water, the amount of water 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 with a certain level of water pressure to the entire city with many undulations.
Wastewater treatment facilities
Wastewater treatment facilities
Wastewater treatment facilities
Concentrates and dehydrates the impurities removed from the sinking pond and the filter pond. These materials are effectively used as construction materials.
For inquiries to this page
Water Works Bureau Water Purification Department Water Purification Section
Phone: 045-671-3544
Phone: 045-671-3544
Fax: 045-212-1158
Email address: su-josui@city.yokohama.jp
Page ID: 869-606-860
