Primary treatment Preliminary treatment Bar screen Raw Debris Gint remos To landfill Primary treatment To remove particulate organic material Water enters at center and flows out aver weir at velocitv. Particulate Rotat organic material settles Constitutes water Fat and oil float to top and are skimmed off Fertilizer
Primary treatment
In older sewage-treatment plants, the water after primary treatment is often chlorinated to kill pathogens and then discharged into a natural waterway. The discharged water at this stage still contains a large amount of oxygen-consuming wastes, which may deplete dissolved oxygen in the water way and cause eutrophication
In older sewage-treatment plants, the water after primary treatment is often chlorinated to kill pathogens and then discharged into a natural waterway. The discharged water at this stage still contains a large amount of oxygen-consuming wastes, which may deplete dissolved oxygen in the water way and cause eutrophication