No black water tank needed - Bacterias at work

[Mike (ex-f-221)]

Found in a German RV-magazine:

Something useful for small RVs: A little biological sewage-treatment plant. You don?t need a black water tank anymore. The plant converts excrements into grey water. A German company developed it and will start to sell in fall 2007.

Two kinds of bacterias
It?s simple: you put two kinds of bacteria together in the toilet ? one after another ? and flush the toilet. In an extra tank the bacterias start to increase and after a few hours the plant is ready to work.

Continuous process
Once activated the excrements are chopped and pumped into the separate tank where the bacterias are working. A pump leads air to the tank; the bacterias need that for working, for decomposing excrements and urine. After 22-24 hours that will be done and the rest is grey water which is pumped into the grey water tank. This process is a continuous one.

Easy to restart
If the procedure is stopped by not in use a long time (a few weeks, will stop the process) or using a chemical product (which will kill the bacterias) you can initialize the procedure after flushing the toilet and cleaning the system. Just add the bacterias with a teaspoon from two bottles.

Do?s and don?ts
- Only use TP which decomposes in water
- No waste into the toilet
- No Chemie ? that kills the bacterias

A small one
The system currently is a small one. So the extra tank is about 20? x 14? x 14?. Maybe someday the system is available for greater volumes.

 

[John From Detroit]

Not an expert here but I think there may well be some other issues.. Legal type

Many places have rules about black and gray

 

[Just Lou]

Duh ??

Where's the payoff?  A chemical tank or a black water tank?  What's the difference?

I ain't gonna dump the gray water anywhere but in a sewer anyway....

Sounds like a GREAT solution to a NON problem to me.

lou

 

[Mike (ex-f-221)]

Lou,
there is no chemical tank and there is no black water tank. Just a grey water tank. The bacterias make grey water out of black water.
It is not a big solution for MH but a clever solution for smaller vehicles i.e. such with portable black water tanks.

Look the attatched pic that explains it better than my poor words.

 

[Ned]

I don't see the advantage for any size RV.  The extra tank is as big as many black water holding tanks, so where's the savings?  Since you can't dump gray water anywhere but into a sewer system, the single tank is no advantage either.  Looks like another solution in search of a non-existent problem.

 

[Karl]

In addition to the below, there's another problem: If it needs 22-24 hours to digest what's in the tank, do you 'hold it' for that period of time? I think not. If you don't, you're adding unprocessed waste to partially processed waste and pumping a mixture of the two into the gray tank. Not good.  Also sounds like the air pump is running continuously - noise, electricity.

 

[UK-RV]

I "THINK" (only think, but will check) the reason for the single grey tank is as follows :-

In Europe, you can dump your grey tanks into any sewer without issue.

As the black tank (nearly always) contains chemicals, it has to be dumped in a special Chemical Dump Point and not straight into the sewer.

So, Im thinking the device would avoid having to find a CDP at all as it is all grey.

Paul

 

[Tom]

As the black tank (nearly always) contains chemicals, it has to be dumped in a special Chemical Dump Point and not straight into the sewer.

I suspect that's true in Europe Paul, but most folks here don't use any chemicals in their black tank.

 

[Mike (ex-f-221)]

Have to mention that most of the RVs in Germany (as in other european countries I believe) have no voluminous black water tank but little toilette cassettes (see attatched picture) with a volume less than 20 litres. They have to be emptied from time to time. You have to take the full cassette out of a compartment at the outside, carry it to the dump-facility and pour it out (a funny job, which everyone likes to to ;D ), flush it and put it in the compartment again.
You don't have to do that when the little biological sewage-treatment plant is installed.

@Paul:
You have not to use special Chemical Dump Points for black water. Only a sewer, where houses are connected with. Not every sewer because in Germany there are many splitted sewers: One of them for all black and grey water from the households and one for the rain runoffs from roofs ans streets. At nearly all places you can stay a while with your RV there are such sewers.

@ Karl:
There is no black-grey-water-mix pumped into the grey water tank. Only grey water is pumped from the biological sewage-treatment to the grey water tank.

 

[Tom]

Very interesting Mike. Some RVs here in the U.S. have portable toilets that have to be emptied manually. The lower half looks like the cassette in your photograph but the cassette is usually attached to the toilet bowl instead of being stored in a separate compartment.

 

[Karl]

Mike,

There is no black-grey-water-mix pumped into the grey water tank. Only grey water is pumped from the biological sewage-treatment to the grey water tank.

Not to belabor the point, but having reviewed the diagram, I can't see how you can use the toilet and not have untreated effluent mix with partially treated effluent in the processing tank. What am I missing? :-\

 

[Mike (ex-f-221)]

Tom,
the cassette is directly unter the toilet - and the toilet is directly at the wall. so the Cassette is direct at the wall too - in a separate compartment.

Karl,
good point; I sent a mail to the company and asked how they assure that only grey water is leaving the plant. Will report when answered.