Looking into composting toilet

[PaulBartomioli]

Human solid waste should NEVER be used for compost in vegetables meant for human consumption. I got this advice from one of the manufacturers I contacted about this issue.

[Mike OReilly]

Originally Posted by Coyote24

Composting: do our business, end-up with dirt, put in the garden, = better vegetable.
Is that not the case?

No. The end product from these heads is definitely not fully composted human waste. To fully compost, the material must be left for many months. Unless you can leave the head alone for all that time, it is definitely not fully composted.

What a composting head does is start the compost process. But its main action is to dry the feces. They're really more desiccating heads than composting heads. In fact, I wish they didn't call them "composters"; they're really not.

And to further answer your question, it's generally not recommended to use human-origin compost on food crops. The risk of passing on a pathogen is just greater. That's why we tend to use animal waste for fertilizer, not human.

The end product of these heads would be fine as fertilizer for plants not destined for the dinner table. But I would keep it away from your vegetable garden.

Originally Posted by Coyote24

If that is the case than I may as well pee overboard and poo in a bucket lined with a plastic bag, no?

Yup, you could. Except the feces-in-a-bag would be pure shyte, whereas the end product of one of these heads is a dried mix of coir that is partially composted/mostly desiccated. The end product looks and feels like rich soil.

But yes, some people use the bucket and chuck-it option, and that is fine as long as you're sufficiently offshore. There are also some 'wag-bag' heads that basically contain all the raw outflows in a sealed bag.

Originally Posted by Coyote24

Also, a few post are for boat around 26ft, the smallest head I can find suggest 5ft headroom, 3.5ft before your knees hit the door and the width appears reasonable. How do you fit this in a 26ft boat? Do you make some cuts to fit it in?

Size is an issue for these commercial heads. C-head has the smallest space needs, although this new Compocloset mentioned earlier looks pretty small. Air and Nature's definitely require more space. But many in your situation have made their own custom-designed head.

[SuW]

Even animal waste is sometimes dangerous when not properly composted - for example, the infamous E.coli water contamination disaster in Walkerton, Ontario years ago, and on-going issues with lettuce and other green leafy vegetables, sometimes from California.

In my yard, I keep a separate 4x4 foot compost pile for the output of the Nature's Head. Layer that with dried leaves, chopped prunings and green material. It rots down over a few years to an odorless crumbly mulch. I use it around trees and flower beds, not on vegetables.

Compost piles can get extremely hot when rotting down in the summer, well over 50C (120F). This can be accelerated by insulating the pile once it gets going (I drape a piece of old shag carpet over the top). The heat is said to kill any weed seeds and pathogens, but I still don't use it for food grown in the soil. I have plenty of other compost for that.

In the 1000 Islands park islands there are large composting toilets (outhouses) for the use by boaters and campers. They are emptied every year and the residue goes on the soil around the trees. They don't particularly like the idea of people adding their own toilet output to the pile (because people are stupid and put their chemical toilet contents in there which doesn't help the decomposition process!)

I had a long discussion with a Park supervisor a couple of years ago (after I told him that I'd seen plastic-based diapers in the pile) and I learned the hardships of their job! Having to pull out junk by hand from a pile of human waste seems like a cruel thing to ask students to do. He said it was character-forming...

In short, I wouldn't hesitate to put a bucket of composting toilet waste in the outhouse w.c.

...and unless you've eaten it first, it shouldn't go in the head...!

[Coyote24]

Hi All,

First thanks for all the replies.

Full disclosure my earlier note was quickly written and comes from when I was a child and spending summers on the family farm.
There was an outhouse and every couple of summers the outhouse would be moved, the remaining pile of ... stuff... would be added to wood chips from cleaning the wood shed and miscellaneous food scraps.
As a kid it was horrifying to be ask to go and 'turn the pile".
(That would be one of the older piles not the "recent" one).
So pitch fork in hand with big black rubber boots here I went and was surprised that the pile was steaming hot but not smelly or disgusting.
I learned what composting was.
I always thought it was then used in the garden but perhaps it wasn't.

In any case my question was more, so what gets out of the composting toilet if not compost?

And to that end, the trophy goes to (drum roll):

Mike O'Reilly

Fantastic thoughtful reply (as are the previous ones you wrote) thank you mate!

So our situation is we realized we underused our previous 36ft boat because it simply took too long and too much effort to get going but yes once on the way, comfort, a bit more speed etc.

At the moment we might go for a day or weekend cruise and a few times a year maybe a week long escapade. The current head flush direct overboard and I am not to incline to install a tank a macerating pump a fitting on the deck and loose all that space in the cabin(!).

But if a composting head does not produce compost than I still have to dispose of its content somewhere. Is it that the content can now be thrown in the garbage bin while a bag of raw sewage cannot ??

I think I am having a brain fart, I cannot figure this one out...

a.

[Mike OReilly]

Originally Posted by Coyote24

At the moment we might go for a day or weekend cruise and a few times a year maybe a week long escapade. The current head flush direct overboard and I am not to incline to install a tank a macerating pump a fitting on the deck and loose all that space in the cabin(!).

That's one of the great advantages of a composting head; they take up much less boat space compared to a standard marine head with a holding tank.

Occasional use as you describe would likely result in an end product that is much further along to being fully composted. It still wouldn't be done, but the longer you can leave the pile, the more composting action will take place. With your usage you could possibly go many seasons before having to empty the main tank (depending on how many people are using it).

Originally Posted by Coyote24

But if a composting head does not produce compost than I still have to dispose of its content somewhere. Is it that the content can now be thrown in the garbage bin while a bag of raw sewage cannot ??

A composting head can produce compost if the material is left long enough. It's just that in normal head usage, the material doesn't have enough time to go to completion. This is especially true for folks like me who live on board full time (for about 1/2 of each year).

Sue's approach is ideal. All you need is a chunk of land somewhere.

BTW, raw sewage is being thrown into municipal waste systems all the time. I don't know of any laws which make this illegal, although it's probably not encouraged either. The end product of a composting head is far less offensive than a bag or diaper of poop, but it still contains human feces.

There are heads which contain everything in sealable bags. These bags are then dumped in the municipal garbage system. Look up "wag-bag automatic toilet."

I hope this helps.

[captlloyd]

For what it’s worth, the companies pumping septic tanks where I live routinely dump the contents on farmers fields. ( Ohio). It is legal. Yes, wow !

[SuW]

Originally Posted by captlloyd

For what it’s worth, the companies pumping septic tanks where I live routinely dump the contents on farmers fields. ( Ohio). It is legal. Yes, wow !

Yeah, it's legal and probably not all that harmful. It used to be common in the developing world. Farmers also apply manure from their animals on their fields. Basically, light, dilution and time will render most pathogens harmless. Most.

[SuW]

Originally Posted by Mike OReilly

...There are heads which contain everything in sealable bags. These bags are then dumped in the municipal garbage system. Look up "wag-bag automatic toilet."

I hope this helps.

lol, yeah...flying toilets! Now that's yucky!

[Mike OReilly]

Originally Posted by captlloyd

For what it’s worth, the companies pumping septic tanks where I live routinely dump the contents on farmers fields. ( Ohio). It is legal. Yes, wow !

How do they manage all the various odd chemicals dumped into septic tanks Lloyd? I've heard of human waste being used on non-food crops, but wow... Ohioans must be tough .

Originally Posted by SuW

lol, yeah...flying toilets! Now that's yucky!

Haven't heard that one. Eew!

"Flying toilets," or wag-bags, are how we commonly deal with doggie poop bags. Dumping these things is certainly more gruesome than anything that comes out of a composting head.

[Scorpius]

Originally Posted by thinwater

I tested a bunch of absorbents for an up coming article, and coir was not the lowest odor (aspen pet bedding, local mill work sawdust, and fireplace ash were better). Since these are waste products, are locally available, and would otherwise go to the landfill, they are more sustainable. Coir is more compact (6:1 vs. 3:1), but there is also the hassle of re-hydrating coir, so I found aspen bet bedding more convenient for me. It is also what C-Head recommends. (Aspen pet bedding is indistinguishable from my local millwork shavings, except a very small amount of fine material has been removed and it is compacted.)



[Wood burning ash is the clear winner IMO for people that use wood heating (boat or home), but otherwise no. It can be a bit messy, but not with care. The trick seems to be that the high pH helps dehydrate the waste and suppress acid gases. More of a cabin trick than a boat trick.]

I remember that, as a kid in the 1950's, at our family cottage near Pender Harbour (now my home) we had a wood stove for cooking and as our only source of heat. Our toilet was an outhouse 50 yards (it seemed at the time) up the hill from the house.

It was standard practice (assigned to either my brother or me) every morning
to clean the ashes out of the stove, take them out, and dump them in the outhouse. This was, I understand, a very common procedure amoung rural residents and was used to promote the composting and keep the odour down.

[Phantom Jim]

I have become aware of a product named Sweet PDZ, used in horse stalls to absorb ammonia and help deodorize manure areas. It is a natural product, zeolite, that is from volcanic activity and can be part of a composting process if so chosen. It is available at Tractor Supply for about $13 for 25 pounds, approximately 0.75 cubic foot.

I will test this product in a few months but would propose that any who are currently using a compost toilet do an evaluation of this product.

My thought is that this product may allow a reduction of the volume of biolitter needed to cycle a compost toilet. This would the most benefit for sawdust toilet users who use about 3 gallons of biloitter per cycle. If the volume of bioitter could be reduced perhaps even by 1/3, that would significantly reduce the time between disposing the contents, perhaps from 3-4 days for two adults to 4-5 days.

This could also benefit separating compost toilet users as well but to a lesser extent.

[captlloyd]

Originally Posted by Phantom Jim

I have become aware of a product named Sweet PDZ, used in horse stalls to absorb ammonia and help deodorize manure areas. It is a natural product, zeolite, that is from volcanic activity and can be part of a composting process if so chosen. It is available at Tractor Supply for about $13 for 25 pounds, approximately 0.75 cubic foot.

I will test this product in a few months but would propose that any who are currently using a compost toilet do an evaluation of this product.

My thought is that this product may allow a reduction of the volume of biolitter needed to cycle a compost toilet. This would the most benefit for sawdust toilet users who use about 3 gallons of biloitter per cycle. If the volume of bioitter could be reduced perhaps even by 1/3, that would significantly reduce the time between disposing the contents, perhaps from 3-4 days for two adults to 4-5 days.

This could also benefit separating compost toilet users as well but to a lesser extent.

I don’t see how you can beat coconut coil as a medium, especially for cruisers. It is not expensive, it is compact in the brick form and can easily be expanded for use, and there is no appreciable odor issues. And Amazon will deliver.

[captlloyd]

Originally Posted by Mike OReilly

How do they manage all the various odd chemicals dumped into septic tanks Lloyd? I've heard of human waste being used on non-food crops, but wow... Ohioans must be tough .



Haven't heard that one. Eew!

"Flying toilets," or wag-bags, are how we commonly deal with doggie poop bags. Dumping these things is certainly more gruesome than anything that comes out of a composting head.

I would bet good money that Ohio is not alone in this practice.

[Mike OReilly]

Originally Posted by Phantom Jim

I have become aware of a product named Sweet PDZ, used in horse stalls to absorb ammonia and help deodorize manure areas. It is a natural product, zeolite, that is from volcanic activity and can be part of a composting process if so chosen. It is available at Tractor Supply for about $13 for 25 pounds, approximately 0.75 cubic foot.

I will test this product in a few months but would propose that any who are currently using a compost toilet do an evaluation of this product.

My thought is that this product may allow a reduction of the volume of biolitter needed to cycle a compost toilet. This would the most benefit for sawdust toilet users who use about 3 gallons of biloitter per cycle. If the volume of bioitter could be reduced perhaps even by 1/3, that would significantly reduce the time between disposing the contents, perhaps from 3-4 days for two adults to 4-5 days.

This could also benefit separating compost toilet users as well but to a lesser extent.

An interesting experiment Jim. I'm sure those who use sawdust-style toilets will be very interested in the results.

But at the risk of sounding pedantic, standard desiccating (composting) heads already go for four to six weeks for the larger versions (Air/Nature's) and two to three weeks for the smaller C-head style.

[Phantom Jim]

I agree Mike, the advantage for a separating compost toilet is probably insignificant. A reduction of the amount, say 1/4 to 1/3, of the biolitter for a non-separating sawdust toilet would be significant.