How Does a Waterless Urinal Work?

Piqued by curiosity because I mentioned waterless urinals in a recent post about urine as a fertilizer, I decided to find out how waterless urinals worked. It's amazingly simple apparently.

Once you pee into the urinal, the pee goes through a sealant liquid which is lighter than water. If you've ever seen a muti-layer candle, it's the same principle.  The oil floats on water and it looks cool because you have flame over water.

Since the urine is denser than the sealant liquid (oil I believe), the urine goes straight through liquid and through the drain while this liquid stays on top. This effectively seals urine out preventing any bad smell from seeping back into the restroom. And there is absolutely no water waste. It's also cheaper than flush urinals because there's no flushing mechanism.

The best part of course and a major reason for this post is that each waterless urinal can save up to 40,000 gallons of water per year.  You also just need to replace a filter a couple of times a year.

The only drawback is that waterless urinals don't remove the odor staining the surface of the urinals.

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