Waste system to get pure water out of human excretions

[caters]

I was thinking about all the excretions and body fluids that end up in sewage and thought "Bacteria and oxygen might do it for less cost but it is less efficient than my method"

So here is what I was thinking. At some point in the pipes there is a poop catcher and right next to it a valve that will only open when there is no fluid. This diverts the poop to a different set of pipes that eventually leads to making a human poop biosolid.

Meanwhile, the rest of the fluid continues on through a series of 7 filters each designed to catch something you don't want in the water and is microscopic. The first filter blocks cells(so blood cells, bacteria, fungi, protozoa, endothelial cells of the bladder and digestive tract, etc.)

The second filter blocks viruses so now you don't have to worry about waterborne transmission of a stomach virus. The third filter blocks pepsin and other enzymes. This is exclusively from vomit. The fourth filter blocks undigested nutrients(so triglycerides, polysaccharides, polypeptides, and DNA and RNA sequences). The fifth filter blocks unabsorbed nutrients(so amino acids, simple sugars, glycerol and fatty acids, and nucleotides along with any vitamins that didn't get absorbed. Minerals like iron are so small that they pass right through). The very last filter blocks urea molecules.

Now all that is left is saltwater, HCl, and ions.

This acidic saltwater then goes into an area where there is a precisely controlled acid base reaction so that no HCl or NaOH is left after the reaction.

Then the saltwater that has ions like potassium and iron gets deionized and you have pure water.

But is this doable?

[beecee]

From memory [someone please correct me if I am wrong] they do similar on the ISS...well partly anyway!

 

Edited July 28, 2017 by beecee

[Bender]

In a way, it is already performed on a large scale for as long as there was poop. If your poop gets dumped in surface water, bacteria and other organisms break it down.

In some places, a lot of homes have septic tanks, where naturally occurring bacteria preliminarily break down human waste to an relatively clear and odourless fluid before it is dumped in the (possibly open) sewer.