Many cities send their sewage to be used as farm fertilizer. But waste treatment plants don't typically remove "forever chemicals," first.

The thickening agents keep the ingredients like ... Through a process called sedimentation, particles and liquids separate when they are left alone for a period of time. Because the particles ...

The wastewater then gets moved back to another sedimentation tank where more solids are removed. The solids that are removed at each step of the process are put through thickening centrifuges ...

The wastewater then gets moved back to another sedimentation tank where more solids are removed. The solids that are removed at each step of the process are put through thickening centrifuges, then go ...