RE: [VAL] Recirculating toilets

["Forrest McClure" <rollie51@xxxxxxxxxxx>]

Jo Ann,

A recirculating toilet is one type of portable toilet. Portable
toilets most often have a holding tank and smaller water tank built
in. The water tank supplies water to flush with. So, it is
"self-contained." Usually the holding tank is removable so that it can
be carried to the latrine for dumping.

Portable toilets with a larger holding tank and that have a 'built in'
look are called "cassette toilets." These can be quite sophisticated
in that the holding tank can be removed, just like a cassette, and
taken to the latrine for dumping, or sometimes there will also be an
optional dump valve mounted on the outside of the RV for disposal in
the same way that an RV with a septic system disposes of waste. Some
of these cassette toilets have holding tanks as large as the septic
tank in a small trailer. This might be about 8 gallons.

A recirculating toilet is similar to both, but is generally much more
expensive. A recirculating toilet does not have or need a water tank
for flushing - you guessed it - the fluids in the attached holding
tank are recirculated for flushing. This gives them a greater holding
capacity than standard portable toilets because fresh water is not
added to the holding tank with each flush. A recirculating toilet
depends then on a filter so that the fluids can be separated from
solids and other particulates to accomplish the flushing action. That
is about all I know about them, and just about all I want to know
about them.

I imagine a recirculating toilet uses "blue water" similar to what is
used on aircraft. The filter does a good job, but how I know not. Once
the holding tank is full it is detached and carried to a dump station
or latrine same as with a portable toilet. Some recirculating toilets
can be hooked up to a remote tank for extra capacity (such as the
holding tank in an RV). I know several vintage owners who have
retrofitted this type of toilet into their older (50's and 40's)
Airstreams that either didn't have a septic holding tank or that
didn't have a toilet to begin with, and it works quite well for them.
A standard portable toilet costs around $100 to $150 and a good
recirculating toilet (and I bet you'd want the good one) costs around
$500.

So, the question is why don't we all have one of these type of toilets
instead of the septic system commonly used? Wouldn't there be greater
versatility? Wouldn't it be cheaper? Wouldn't it require less
plumbing, or no plumbing? Well yes, yes and yes, but all of these
types of toilets require deodorant exclusively to control bad odors.
They do not have a venting system that allows methane and other odors
to escape through the roof vent as with a standard septic system
(although I have read of one cassette system that does), and an 8
gallon capacity is about as large a holding tank as can be built into
a portable. Imagine trying to carry 8 gallons across the campground to
the latrine for dumping (I suppose that wheels could be attached).

By now of course you are probably thinking, "ask a simple question..."
Sorry, about the long answer, and I hope it was not more information
than you wanted or needed.

Forrest McClure
VAC Librarian