ELI5: How do compost toilets work

[vjm]

Originally Posted by alansmith

You see guys going through all sorts of modifications so that their toilets don't stink. Watched a video just last night of what a guy did on a large cat to get fresh water to his flusher. He had two. Electrical mods, valves, new pumps, t's....wow....


I do like the two ideas presented during this thread of plumbing the urine to a holding tank and making some sort of stand up (maybe like they do at port-a-Johnny u would use at a concert) piping modification.

Ecovita has some kind of "dry urinal" on their site. Never looked at it but might be an inspiration.

[Minggat]

Originally Posted by boatster

Do composting heads have to be vented or can they be self-contained like a porta potty?

My C-Head came with the vent. I didn't install it with a wait and see attitude.

Short answer to your question-
Yes. Self contained, if you don't otherwise trap the moisture.

My C-Head also came with a lid. So when you open the seat, you see this lid with a handle. I used the lid at first and noticed that it was counterproductive to the drying process. Lots of moisture trapped. I set the lid aside and things dry out as needed. If I had gone to the trouble of installing the vent, the lid still not make much sense to me. I think it may be provided to help some people get past the "eeeuuuu" factor.

As far as going to the trouble to set up a urnial for the guys, let's see how much work we can make for ourselves.
Nobody is allowed to pee off of the stern either. The dedicated (each male gets his own) liquid laundry detergent/ pee bottle has a really effective seal and wide opening. It also starts out strongly perfumed!

[ZipTie]

Maybe this will help.

http://www.cruisersforum.com/forums/...ml#post2050770

[drsm]

Another vote for the C-Head, here. We don't have ours ventilated, and it works just fine. I'll be adding one to our camping trailer soon, but that will be ventilated, because the trailer is not constantly ventilated like the head in our boat, which has a dorade vent in it.

For info on our installation in a Fuji 35 ketch: Steve & Kathy's Website: Installation of a C-Head composting head in our Fuji 35

Steve

[FSMike]

Composting head on our boat is vented through the deck via a solar/battery exhaust vent, never smells.

[Blue Crab]

Ditto for my C-Head. No smell, no vent.

When we face facts, some folks are very fecal sensitive. Since the OP asked for a simple explanation, let me add to this:

Back to the "cat box" principle.
Life got even more simple once I started treating it like a cat box. For any more details than that, just think about what it takes to make that work, minus the smell. I have not changed out a batch in well over a year. I Just top it up.

I use coconut coir simply because you can buy it in compressed bricks. Sawdust works very well. __________________
Minggat

OP: Really, Mingatt is saying to scoop out the clumps as it gets difficult to stir the crank (weekly, say). Pretty simple but for one thing, the need to put the TP in a separate container. I am not a real fan of this, but it sure makes toileting simpler, as noted above. I also use the pee jug which gets dumped each morning. I also think the no dumping zone question hasn't been answered for Florida yet. The solid disposal is easy and there isn't much problem but if no dumping means no dumping than presumably the urine will have to be carried ashore as well. I know of only one person who does this.

I'm in an area with no rules for salt water dumping, but as a diver, I just don't want to dump solids where I clean the boat bottom, etc. I think the "flush and forget it" crowd are thoughtless rookies, given the ease of using a "composting" head. I'm not talking about human waste compared to whale waste, but simply in my or your local anchorage.

[newhaul]

Originally Posted by Minggat

) liquid laundry detergent/ pee bottle has a really effective seal and wide opening. It also starts out strongly perfumed!

A teaspoon of sugar will stop the urine stink factor to a major degree

[lindabarzini]

Thanks for all the great responses. I currently call my boat "The Fecal Bouquet" so I am very sensitive to this smell issue.

It looks like a good solution. I am skeptical about odor, but separating the liquids makes sense, so no "sewage" is created and dehydrating solids with coconut coir and a venting fan makes sense.

I may give this a try. I would like to see some in action though.

[Mike OReilly]

I did a lot of research before taking the plunge with our Nature's Head lindabarzini. When I finally made the move I left all the existing head plumbing, including the holding tank, in place for the first season. That way if the composter didn't perform as advertised, I could easily swap back my standard marine head.

Needless to say one of the first projects for our second season with the NH was to rip out all the hoses, tank and valves for the standard head. I would never go back.

[FSMike]

Originally Posted by Mike OReilly

----When I finally made the move I left all the existing head plumbing, including the holding tank, in place for the first season. That way if the composter didn't perform as advertised, I could easily swap back my standard marine head.

Needless to say one of the first projects for our second season with the NH was to rip out all the hoses, tank and valves for the standard head. I would never go back.

The previous owner did the same on our boat, but never removed the old plumbing. I just finished doing this. What a pita! I see why he didn't do it.
Only thing left is to remove the old through hull at the next haul out.

[Minggat]

"..... and a venting fan makes sense....."

Sorry. I'm confused. I do see where I may have added to the confusion in my earlier post.

My "yes, self contained" should have read- no- vent not required. I now understand that it depends on which unit you purchase.

Methinks you worry too much.

Yes. With some designs, I now know that a venting fan would be required.

I'm glad that I picked a unit that included a vent, should I decide that it made sense. After determining that it didn't make sense, I am happy to have saved myself the trouble of cutting a hole in my deck to install it.

[Blue Crab]

I too no longer use the "lid." It does trap moisture. My bet is Sandy's advertising division executives insisted on it for the squeamish non-believers.

And +2 for returning the used peat to nature. It's enriched, and will recycle far faster this second time around. Another +2 for Ol' No. 2.

[Mike OReilly]

Originally Posted by FSMike

The previous owner did the same on our boat, but never removed the old plumbing. I just finished doing this. What a pita! I see why he didn't do it.
Only thing left is to remove the old through hull at the next haul out.

Yes ... removing all the hoses, valves, tank and sealing off the unneeded thru-hulls -- this is definitely the biggest part of the job. In our case recovering all this space was one of the primary reasons to make the switch. In the place that held our old holding tank I now carry two inflatable kayaks, my epoxy kit, some miscelaneous tools and our spinnaker and drifter. I love it!

[Nicholson58]

Originally Posted by Chuck Hawley

On a related topic: I've often wondered if urine can be dumped overboard anytime, even within three miles of shore. The argument would be that it doesn't contain coliform bacteria, so is not regulated. Putting it another way, the effluent, if pumped out, would show zero % of the substance that the MDS laws are based upon. Plus, I believe it's sterile.

Just asking.

This would essentially mean you could dump urine without fear of repercussions.

Cheers,

Chuck

Yes but don't get caught doing it. Please don't do it in the marina or harbor. Rafting on the Colorado they insist you pee in the river but must dig and bury feces above the water mark. No different than taking a leak off the lee quarter or while swimming.

We have a Nature's head and a spare urine receiver. Easy to dump these in a toilet at a marina. The feces pot will operate with two people for about 2-3 weeks. Well operated, it smells like a bucket of Uncle Bucks night crawlers. We take it ashore in secluded areas and bury it in the woods. I recharge the pot with dry leaves and humus. The electric ventilator is solar powered. Sailing in the Great Lakes North Channel, this is way better than having to pull anchor to look for a pump station.

[tankersteve]

I'm convinced and actuallly have a cardboard mockup of the C-Head in my boat. Once my critical work is done, it is high on my list of upgrades.

However, I have to admit, I was not tracking the need to separate the TP. Does anyone not do this? I understand TP would inhibit just putting the dessicated waste in a flower bed, but if disposed of in other ways, is there any impact in TP going in with the solids? Possibly using camper/RV TP to aid in breakdown? Or is this just something I'll have to adapt to?

Thanks.

Tankersteve