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Old 08-30-2009, 11:56 AM   #65
Ran D. St. Clair
Senior Member
 
Join Date: Apr 2009
Posts: 212
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Toilets stink…

I had already decided that I would not have a black water tank, and when Geofkaye wrote of the INCINOLET I was immediately impressed by the idea. I started an internet search for it, and along the way I stumbled on to the ECOJOHN, which is basically the same idea, only propane powered. I also looked at various other technologies before deciding to go with an incinerating toilet of some sort, so lets begin with what I didn’t choose.

Starting with the simplest, you can buy a toilet seat for a 5 gallon bucket. It’s dirt cheap and I do like cheap. I even bought one and tried it out. It worked, but there were a number of problems. The opening is a bit small compared to a standard home style toilet, so it’s a bit awkard to get everything to go in the right place. It’s also a bit low and not the most comfortable thing to sit on. The biggest issue though is the smell. Dumping your load into water immediately seals it off from the air and keeps the initial smell way down. Dropping it into open air just seems to invite the stink to come for a visit.

http://www.cabelas.com/p-0009518.shtml

You could line it with a plastic bag, and then immediately seal it off after use, but my experience was that you can’t seal it off fast enough. The bag would, however, make disposal a lot easier. Yes, I know, the idea of dumping your waste in a public trash can sounds bad on several levels, but it is no different than what dog owners do all the time. You could also put some kitty litter in the bucket, or in the bag in the bucket. I didn’t try it but I am sure it would work to some degree. Presumably you could use it more than once before dumping the bag, kitty litter and all, or you could do the scoop thing. From what I know of cat boxes, they don’t generally smell so good, but lots of people have them in their home, so I guess it could work. Ultimately I decided I didn’t want that kind of smell in my tiny living space.

Several companies make small self contained chemical toilets. It amounts to a seat on top of a black water tank with some small flushing capability. I won’t say if it’s a good idea or not. I can see where they could work temporarily, but eventually you have to dump and clean the things, and I would have no good way to do that, so the idea never really had a chance.

http://www.rvstuffusa.com/port...ti135bythetford.html

There is something called a composting toilet. In this case you dump into a disposable cardboard box. The box sits on a hot plate, which dries it out, but does not burn it. Clearly cooking crap is going to stink, at least until it dries out, so this idea uses a small fan which is continuously drawing air into the unit and then venting it overboard. I could see where this could work fine in a cabin where you have a steady supply of electricity to run the fan. (The hot plate only runs briefly) Besides the electricity used, which is really not all that much, there is the additional heating and cooling costs associated with constantly venting air. On the plus side, it makes good garden compost, not that I care.

http://ecojohn.com/ecojohn_basic.html

Obviously there is the standard RV style toilet with a black water tank. I will let others who know way more about them than I do speak to their advantages and disadvantages. I will have no good way to dump a black water tank so it doesn’t work for me.

Finally, we come back to the incinerating toilets, of which I found two. They may be similar in terms of their ultimate goal but there are lots of differences, and only one of them could work for me, the ECOJOHN. I expect that most others, however, would be better off with the INCINOLET.

http://ecojohn.com/ecojohn_sr.html
http://www.incinolet.com/

The ECOJOHN model SR5-P12 is $3,695 compared to $1,779 for the RV model INCINOLET. When I added bowl liners, catalytic converter (to reduce smoke), stainless steel bowl (upgrade), sales tax, and shipping it all came to $4,725 for the ECOJOHN, which is admittedly a LOT of money for a toilet. Especially for one that I have never used. I am taking a substantial risk, and I will just have to let you know how it all works out when the time comes.

I had to choose the ECOJOHN because of the AC current required to run the INCINOLET, which is for better and for worse, all electric. Based on the manufacturers data sheets, the INCINOLET draws about 15A at 120VAC for about 50 minutes to complete a flush cycle. My generator can only manage 13.3A continuous. If I tried to run it off my batteries, just one flush would take my batteries down to half charge, which is the stopping point. It would draw 167A DC which is more than I should be drawing from my batteries just in terms of raw current, not counting anything else electrical I might need at the time. I could run the generator while it is "flushing" which would give me 90A from the battery charger, so only 167 - 90 = 77A from my batteries, which is at least possible, but now I have to remember to fire up the generator before I flush the toilet. Since flushing is something I want to be able to do somewhat spontaneously it really doesn't work.

The ECOJOHN draws very little current from my batteries, just .312Ah per flush, much less for a urine cycle. Most of the energy comes from the propane and I figure there is something like 120 flushes in a 5 gal tank of propane.

The engineer in me really hates the idea of burning gas to make mechanical energy, then electrical energy, then heat energy. The overall efficiency of that chain is around 35% at best. I know, no one but me would even know or care…

The INCINOLET is probably safer, being all electric. There is no potential for propane to leak, start a fire, or explode. Both toilets require a flue to exhaust the hot gasses. The make up air has to come from somewhere, implying that it has to be heated or air conditioned depending on the outside air temperature. The INCINOLET is not without safety concerns. It could short out and start a fire, or leak combustion products into the living quarters, but presumably it is well designed to prevent all that.

The ECOJOHN has all the same issues as a propane refrigerator. I need to set it up to draw in outside air for combustion and to exhaust the hot flue gasses overboard. I need to make sure that those combustion gasses don’t leak into the living space, and I need to minimize the heat that it dumps into my living space. The unit comes with a double walled flue pipe, 6” on the outside, which makes it rather large and obtrusive. It is shiny chromed, but I may want to add a layer of insulation making it even larger. I can drill holes in the floor for intake air, and chimney effect should be more than sufficient if I vent straight up through the ceiling. I will need a vent cap of some sort, hopefully non-obvious.

The INCINOLET is a bit more compact and industrial looking. It requires 6” to 8” of clearance on the right side for access to the foot pedal flush handle. The access to the ash bin is from the front, which IMO is a much better design than the ECOJOHN. The INCINOLET can be mounted flush with the back wall with a special gasket to connect the flue.

The ECOJOHN requires 6” of clearance in the back for access to the ash bin, which is a problem in my application. I intend to create an access hatch through the outer wall that is hidden behind the right rear awning door. Otherwise I have to move the toilet away from the wall and even then the only access would be standing on my head reaching over the top of the toilet, because there is not enough room to come at it from the sides. The ECOJOHN is a bit longer than the INCINOLET 34” vs 24” so an additional 6” makes 40” which is a lot of space to give up in my application.

Hopefully the additional length of the ECOJOHN makes it a little more comfortable and easier to use. IMO, it is a bit nicer looking than the INCINOLET, though that is the least of my concerns.

As for technology, the INCINOLET uses a trap door concept to drop the waste into the incineration chamber. The ECOJOHN uses an auger to screw the waste back into the incinerator. Both units offer paper liners to minimize smearing in the bowl, and in the case of the ECOJOHN, along the surfaces of the auger. The ECOJOHN also has a small reservoir of rinse water to help clean the bowl and auger. As far as I know there is no similar feature on the INCINOLET.

Both toilets can be used again immediately after the incineration cycle is begun. They suspend burning when you lift the lid and resume when you are done. Both units offer a catalyst to reduce smoke and external odor.

Not to be gross, but I fully expect that both toilets will require some manual cleaning from time to time, and I don’t just mean emptying the ash bin. Stuff sometimes sprays, splatters, and dribbles, you get the idea… This may be one area where a more conventional water flush toilet has the advantage.

ECOJOHN also makes a diesel powered version, which some may prefer for safety reasons, or compatibility with your diesel powered truck and generator. If you have a big diesel generator then you probably have no problem with supplying the necessary current to the INCINOLET though.

To be Continued….
Ran D. St. Clair is offline   Reply With Quote