Sewage treatment
Wanna know the difference between barbarism and civilization? Plumbing.
Specifically, a system for cleaning the waste out of your activities (whatever they are). That means, at a minimum, removing sewage. Ideally the sewage is treated to recapture anything useful and ensure whatever is dumped is safe for the (your) environment.
General
- Pre-treatment: obvious stuff like tires and mobsters in cement are screened out.
- Primary: let the sewage sit so that things separate by density.
- Secondary: remove the dissolved and suspended biological matter with microbes (might have to then remove the microbes).
- Tertiary: anything else that might be necessary to render the fluid safe for dumping/use.
Residential Sewage
People are nasty, however, pretty much everything in their sewage can be treated with some sort of natural system.
Industrial Wastewater
If you thought people were nasty, they don't hold a candle to industry. The Primary process is the same for removing really dense things and really not-dense things. Depending on what's in the wastewater, it can required several cycles through each process. For example, neutralizing acids and bases often creates a precipitate that has to go back to the Primary stage for removal.
Water Purification
This is a whole 'nother ball game. Getting water up to the level where people an just drink it straight without fear of biological or chemical side-effects takes real work.
