Composting Toilet in Roadtrek Sprinter

[engnrsrule]

I finished the "Separating & Dessicating" toilet. I reworked my parachute cord system to include a tipping plate that directs solids to the back of the container, and pulling the cord tips the material to the front.

I also note that using coco coir requires loosening the material from its compressed brick form. I made a tool to aid in shredding the material easier and faster than breaking it apart by hand. I cut a piece of PVC panel to about the size of a large hairbrush and drove 30 staples through so the protrude on one side.

Pictures show the
Completed toilet
Seat up (showing diverter and weather stripping)
Paracord Churning mechanism (note actual waste is contained in a bag/liner)
Coco coir shredder

[engnrsrule]

After one 2 day and one week long trip I have some adjustments to discuss.

First off the good news, the diversion for urine works well and it takes a long time to fill the black tank. No odor there. The waterless trap works fine.

Now the less than good news - the paracord system just doesn't work for me. The unit I modeled this after on you tube was higher, and agitation in mine was impeded by the long depth of the #2 part of the diverter. The ability to "toss" and mix the contents with cords alone was ineffective, so I created a sort of teeter totter to "pour" the contents fore and aft. That did not work very well either and also significantly reduced the total volume available. Part of my problem is my objective to not have this unit be too tall.

Also for the ladies, proficiency in using a separating toilet takes some time and effort. Once urine gets mixed in the poop bag count on more odor than the little computer fan can manage.

Before I give up and go back to the Thetford, I am removing the churning system and going to try it with adding material.

Another learning - while coco coir is certainly effective as a composting medium, the time and effort to break down the bricks is a pain. I am going to try a 60-40 mix of wood shavings (like hamster bedding) and peat moss which are more ready to use. My thought is to pre mix and put in ready to go ziplock snack bags and keep handy in the head drawer.

I also took about 3-4 inches off the #2 chute. This enlarges and raises the hole so contributions are less likely to stick to the sides and the useable volume of the container is increased.

Also, since humor is essential, in explaining and pondering the failure of the material to mix, I suggested just reaching in with your "paw" and covering your poo like a cat does in its box. I ran it up the pole but nobody saluted.

[TygerMark]

I just don't get it.

Stirring doesn't accomplish anything.

Adding moss, chips, shavings, and coconut doesn't accomplish anything.

Separate and desiccate accomplishes everything.

[eric1514]

Originally Posted by TygerMark

I just don't get it.

Stirring doesn't accomplish anything.

Adding moss, chips, shavings, and coconut doesn't accomplish anything.

Separate and desiccate accomplishes everything.

That’s how I see it. The waste is not in the toilet long enough to compost.

[TygerMark]

Originally Posted by eric1514

That’s how I see it. The waste is not in the toilet long enough to compost.

Amen, amen, and amen.

Most people simply don't know composting. On that topic, disinformation is rampant.

That's ok, not everyone knows everything.

[engnrsrule]

Originally Posted by TygerMark

Amen, amen, and amen.

Most people simply don't know composting. On that topic, disinformation is rampant.

That's ok, not everyone knows everything.

So Eric and TygerMark, are you saying just collect the poop in bag or container with no medium?

[TygerMark]

Originally Posted by engnrsrule

So Eric and TygerMark, are you saying just collect the poop in bag or container with no medium?

Exactly. Drop all toilet paper in too. Any kind of toilet paper. Your favorite house brand!

[TygerMark]

It looks like your fan can not get a good draw across the top of the solids receptacle.

Although C-head says ventilation is optional, you are in an enclosed van, not an airy boat..

My view is that you really need a fan, and it needs to ventilate properly in order to desiccate solids properly.

[TygerMark]

There are fans, and then there are fans. Make sure yours is fanny enough.

This fan is used by a leading separating desiccating toilet manufacturer.

https://www.digikey.com/catalog/en/p...oaAoA7EALw_wcB

[TygerMark]

Line your solids receptacle with a plastic garbage bag or 2 (use compostable bags if you are going to compost the solids), and place a bungie around the receptacle so that the bags can not fall in on themselves.

Let the fan draw air across the top of the receptacle.

When it suits you,, grab the bag and dispose of it like you would a diaper.

[GeorgeRa]

How is urine odor controlled, is there a valve or container is vented with the same fan?

[TygerMark]

Originally Posted by GeorgeRa

How is urine odor controlled, is there a valve or container is vented with the same fan?

If the urine is diverted into a container inside the toilet, then the fan exhausts any odor.

If the urine passes through a Hepvo valve to an undercarriage tank, you are good.

[eric1514]

Originally Posted by engnrsrule

So Eric and TygerMark, are you saying just collect the poop in bag or container with no medium?

I’m saying that landfills are not the appropriate place to put bags of human waste. Sewage treatment plants are designedl to safely handle that material, not the county dump which is where the waste collected in “composting” toilets ends up.

[MsNomer]

But no one questions the human waste from diapers (from infant to elderly) that goes straight to the landfill.

[eric1514]

Originally Posted by MsNomer

But no one questions the human waste from diapers (from infant to elderly) that goes straight to the landfill.

They should.

[TygerMark]

Originally Posted by eric1514

They should.

What do you propse?

[Bud]

Originally Posted by TygerMark

What do you propse?

But first, why?

[TygerMark]

Originally Posted by Bud

But first, why?

Good question.

[TygerMark]

I doubt any of us ever have had a cow/buffalo chip fire. That is too bad. I am going to do it.

An advantage to the chip fire is.....no sparks.

Nobody says that you have to land fill your chips that have desiccated in the bag.

Have a nice sparkless fire and toast a few marshmallows.

[GeorgeRa]

Still used for fuel in many parts of the World, search for "dung cakes", but it is all animal manure.

https://en.wikipedia.org/wiki/Dry_dung_fuel

https://www.youtube.com/watch?v=iSqJl40OmZ4