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Johkasou Structure

Let's introduce the "mechanism" that cleans the dirty water flushed from toilets and kitchens.
  1. Sewage is firstAnaerobic filter bed tankEnter. In an anaerobic filter bed tank, most of the solid matter (suspended matter) in the wastewater is caught in a plastic filter and removed. In addition, anaerobic microorganisms (microorganisms that thrive in the absence of oxygen) attached to the surface of the filter media eat and remove dirt components dissolved in the wastewater.

  2. contact aeration tankNow, there are various types of aerobic microorganisms (microorganisms that thrive in the presence of oxygen), and with the help of oxygen from the air sent in by a blower, they also eat and remove dirt components dissolved in water. Masu.

  3. The clumps of microorganisms (sludge) that have grown by eating the dirt components are removed in the sedimentation tank, and the clean supernatant water is disinfected with chlorine before being discharged.

  4. In the process of cleaning sewage, dirt components and solids remain in the tank as sludge and accumulate. In order to stably maintain the work of johkasou, it is necessary to create an environment where microorganisms can work vigorously, such as operation and maintenance, replenish disinfectant, and clean the tank to remove sludge.
 There are various structures of johkasou, such as a sedimetation tank without a filter medium instead of an anaerobic filter bed tank, and a moving bed tank instead of a contact aeration tank in which the contact material moves with the water in the tank. The working and processing functions are almost the same.
Mikihiro Mukai (Public Interest Incorporated Foundation Kodokan)​
Japan Education Center of Environmental Sanitation
130-0024
2-23-3 Kikukawa, Sumida-ku, Tokyo
TEL: 03-3635-4880 (Switchboard),


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