Source-separating toilets

- a way to avoid MIFSLA

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Unlike ordinary toilets, where both urine and faeces are mixed with potable water and then the grey water, a source separating toilet keeps the water free from unnecessary pollution. Actually, this is the easiest way to obtain clean water. Just avoid polluting it!

Source separating toilets should not be confused with composting toilets which actually mix urine and faeces, and often other things, and compost it all. Of course, this is a better form of toilet than the common type, but they often give rise to an unnecessary loss of nitrogen.

Because of the large difference in volume and other properties between urine and faeces, they should be kept separate, ant treated as the different things they actually are.

Source separating toilets occur in tvo pricipal forms, the dry and the wet.

In the dry type, urine and faeces are never mixed, but the urine is flushed with about 2 decilitres of water after each usage in order to avoid crystallisation in the pipes.
Faeces are collected in a mini-composting chamber, in which compost worms might be supplied with compost worms for a better sanitation and decrease of the volume. After half a year of worm composting, the volume is diminished to about half, and all pathogenic organisms have vanished.

An unexpected advantage with this type of toilet is that the toilet room becomes free of the odours common in an ordinary toilet room. This is because the air is sucked out from the composting chamber by a small fan to prevent odours. This also clears the toilet room!

The wet type of source separating toilet also separate the urine, but faeces are mixed with a significant amount of water for the transport of the material. Ideally, it should be collected in a tank together with e.g. burnt lime for hygienzation. In som cases, faeces are sepated from the transport water by a passive centrifugation. The transport water is subsequently hygienized or just discarded. A mini-MIFSLA system, so to say, although it naturally is an improvement over standard mixing toilets. It also lacks the above mentioned advantage of odour reduction.

The source separating vacuum toilet constitute in-between these two types. In this type, a small amount of water is needed for transport of the faeces to a tank. This water is drained off and sanitized with burnt lime.

If you want a source-separating toilet but don't have access to a lower floor level, there are also dry types that are placed directly on the floor of the toilet room, with the compost chamber built-in. Such types are the WM-Throne or the Naturum.

For improvement of a conventional, out-door toilet, the Dass-Isak can be used. They are sold by Örnplast.

The most important thing with all these type are, however, that they don't pollute the grey water, and thereby facilitate the use of grey water purification systems.

The notion of source separating toilets is not new. Such devices have been used in eastern Asia close to 5,000 years, but they doesn't seem to be counted here. We are very proud of our inventions here in the western world.

The producers of source-separating toilets are, as far as I know:


Dry Wet Composting
X X  
Örnplast X    

How to purify the grey water

Composting toilets, survey

Sanitation connection

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