Pirate 4x4 banner

1 - 20 of 38 Posts

·
Registered
Joined
·
3,951 Posts
Discussion Starter #1
I was wondering whether it might be feasible or halfway-practical to make a low-buck version of any of the commercially available incinerating toilets. So I started looking at different systems to find out how they work, and evidently Airstream had a system that was offered as a factory option back in the early 70's. All jokes aside, this seems like a great idea - doesn't it? Why aren't there any systems like this available anymore? The best information I've found so far suggests that GM developed this technology, and everything I've read seems to indicate that it worked really well.

As I understand it, a macerator turns the poop into a slurry and pumps it through a small tube into the vehicle's exhaust. I don't know whether they used a drip-fitting or some type of shit sprinkler/injector, but that was controlled by a vehicle speed sensor and an engine manifold vacuum sensor that dictated when the waste was injected into the exhaust. Supposedly, a little vapor and ash are the only things expelled from the tailpipe. The only people that I've seen say anything about the Airstream system all commented that the exhaust did not smell any different.


The only reasons I can think of are:

1) People don't like the idea of burning poop in their cars
I would guess the opposite

2) Plumbing and exhaust modifications make trailer applications a little more difficult
Still, why not on motorhomes?

3) Expense
Personally, I would happily pay a good chunk of money not to have to handle poop


So unless someone convinces me that this is a bad idea, I'm going to build a simplified version of that system into my Deuce conversion. On a scale of 1 - 10, how likely do you think it is that this experiment is going to blow up in my face and splatter shit all over the place?
 

·
Registered
Joined
·
3,951 Posts
Discussion Starter #2
I'm thinking that the best way to do this in my case, would be to re-route the exhaust so that it runs down the length of the box. If I inject the shit-slurry right in front of the cab, it will have over 14ft to burn off. I'd probably have to experiment with a few different injector setups (unless I can find an old Thermascan system to copy), but that doesn't seem like it would be very hard to figure out. The macerator would create a mixture that could be injected in to the exhaust, and would also act as a pump. Depending on how much shit the macerator can push, I guess I might need a secondary pump. But I could make the injector so that it would also act like an adjustable pressure-regulator, and then just use a simple on/off switch.

Am I missing anything?

If this works, I'll only need a very small black water holding tank (maybe just larger diameter plumbing from the toilet to the exhaust injector?), so I'll be able to carry more fresh water AND I won't need to ever dump the black water tank (unless I wanted to clean it).
 

·
Registered
Joined
·
17,127 Posts
From what I just dug up on a Airflow forum and a few other places the, uh, "black water" has to be plumed into the exhaust manifold, not the exhaust pipe. Even if your deuce is a turbo, I doubt it would produce enough heat to incinerate anything much further down the pipe. There are various composting toilets and a couple of hippie-fied "nature toilets" plus a few propane burning models. I think I'd rather just deal with a regular blackwater tank than mess with an expensive bomb in the back or deal with poop smelling exhaust. That sort of deal could make exhaust work a biohazard, lol.
 

·
Registered
Joined
·
3,951 Posts
Discussion Starter #4
It is a turbo-diesel / multi-fuel engine. If the engine exhaust isn't hot enough, could I maybe supplement that with propane heat blown into the exhaust? Hell, I would still consider doing a dedicated propane system if it was halfway efficient (the electric incinerators are ridiculous).
 

·
Limey
Joined
·
3,036 Posts
3) Expense
Personally, I would happily pay a good chunk of money not to have to handle poop
It strikes me that if you are going to build (and test) this thing yourself, you stand a very good chance of getting your hands dirty - if you see what I mean!
 

·
Registered
Joined
·
3,951 Posts
Discussion Starter #7
Yeah I think you're right, but I was referring to a commercially available system. I'm sure I'll be elbows deep in my own poop at some time if I'm living with a portable crapper. The main motivating factor for me in pursuing this is the fact that I won't have to store or dump my black water tank, so I'll have a greater range. I'm thinking in terms of being limited to how much fuel and water I can carry, so I'm trying to address both of those things. I'd like to be able to live and travel unsupported for at least 3-4 weeks at a time.
 

·
Limey
Joined
·
3,036 Posts
I'm sure I'll be elbows deep in my own poop at some time if I'm living with a portable crapper.
Your own poop isn't quite so bad, but other people's... :barf:

Anyway, I'd never heard of incinerating toilets before and I think it may be a solution to a problem I've got too.

Cheers
 

·
Registered
Joined
·
120 Posts
COMPOSTING is better bet!

Problem w/the aforementioned system is that the blackwater is not always under high enough heat at exhaust manifold for system to operate efficiently. Environmental laws would apply, this aside foolish idea these days.

Headline: Man arrested for deployment of WMD, yea, the crap from exhaust of military truck! Man the control freaks will have a field day with it, perhaps banning the civilian population from owning military trucks too.........

The average person would not like to be driving down the road and be behind this type of system because it will remind them of all the empty promises of their political buddies!

However, a "composting toilet" is something that will not smell and always work efficiently too.
 

·
Limey
Joined
·
3,036 Posts
However, a "composting toilet" is something that will not smell and always work efficiently too.
I've had the misfortune of using a composting toilet - and it beats me how on earth you could fit one into an expedition rig.

How about something like this? It might make a good toilet tech thread.

 

·
Registered
Joined
·
120 Posts
Will it fit?

This guy is talking a duce like in 2 1/5 ton mil truck so any crapper to include the new designs of composting toilets would not be a problem fitting.

hoggyn: Tell us about your misfortune on a composting toilet.

Many homes where I live have just composting toilets and no problems as long as unit is sized to handle the intended use. Yea, a unit designed for say 3 people per day can't support say 6 people.
 

·
Registered
Joined
·
3,951 Posts
Discussion Starter #12
Problem w/the aforementioned system is that the blackwater is not always under high enough heat at exhaust manifold for system to operate efficiently. Environmental laws would apply, this aside foolish idea these days.

Headline: Man arrested for deployment of WMD, yea, the crap from exhaust of military truck! Man the control freaks will have a field day with it, perhaps banning the civilian population from owning military trucks too.........

The average person would not like to be driving down the road and be behind this type of system because it will remind them of all the empty promises of their political buddies!

However, a "composting toilet" is something that will not smell and always work efficiently too.
It would be easy enough to control when the system was turned on/off, and the Thermascan system was tested and approved for use on public roads back in the 70's. As long as I modeled my system after that system (assuming it works), I don't see where I'd have any problems. Besides, who's going to know that the soot I'm blowing out is poop ash?
 

·
Limey
Joined
·
3,036 Posts
hoggyn: Tell us about your misfortune on a composting toilet.
I guess the composting toilet that I used must have been 'special'. It did have the bucket of sawdust. It also had flies in plague proportions. Apparently it is necessary for some poor sod to periodically knock the 'peaks' off the accumulated waste. Needless to say, this hadn't been done for a while on the one I used and the resulting 'peak' was almost pushing the lid up.

I still have flashbacks.
 

·
Registered
Joined
·
210 Posts
Crap! (no pun intended... ok maybe it is.) This thread should have been posted at the beginning of April so we could all be guessing about the sincerity of the OP.:D:D Keep us up to date on your build, though.
 

·
Registered
Joined
·
3,951 Posts
Discussion Starter #15
I went and talked to a couple of guys at a local RV shop, and they told me that all of the Greyhound buses uses to have incinerating toilets. These guys said that they worked well, but they were outlawed because of public opinion and misinformation. Hmmm, I'm still seriously thinking about installing a system like this. Even if it's only in addition to a regular blackwater tank. The guys at the RV shop and I were talking about pumping propane into the exhaust to get a full burn. They said that's how all of the smoke-stacks at manufacturing plants reduce emissions. I wonder if it would be possible to make a propane-boosted system that I would work at idle, while the vehicle was parked...
 

·
Limey
Joined
·
3,036 Posts
I wonder if it would be possible to make a propane-boosted system that I would work at idle, while the vehicle was parked...
Have you considered that if anything goes wrong with the macerating stage you might end up creating a rather unpleasant potato cannon?
 

·
Registered
Joined
·
3,951 Posts
Discussion Starter #17
Have you considered that if anything goes wrong with the macerating stage you might end up creating a rather unpleasant potato cannon?
No. At least not seriously. I'm not sure I even understand exactly what you're thinking could go wrong.
 

·
Limey
Joined
·
3,036 Posts
No. At least not seriously. I'm not sure I even understand exactly what you're thinking could go wrong.
Sorry, I suppose I have an overactive imagination. The mental picture of your rig firing high velocity turds across the campground amuses me.

Getting back on topic, presumably the waste has to be fed into the exhaust pipe at it hottest point - in that case will the ash choke up the mufflers further down the line?
 

·
Registered
Joined
·
3,951 Posts
Discussion Starter #19
Sorry, I suppose I have an overactive imagination. The mental picture of your rig firing high velocity turds across the campground amuses me.

Getting back on topic, presumably the waste has to be fed into the exhaust pipe at it hottest point - in that case will the ash choke up the mufflers further down the line?
Oh, it's definitely an amusing proposition. But it's a serious one too.

I've gotten some conflicting information about the exhaust temps and getting a complete burn. Still trying to get to the bottom of that.
 

·
Limey
Joined
·
3,036 Posts
I've gotten some conflicting information about the exhaust temps and getting a complete burn. Still trying to get to the bottom of that.
This thread is full of pun potential :D

According to my 'research', furnace temperatures are normally controlled within the range of 800 to 900°C: at lower temperatures, incomplete combustion and odour formation becomes apparent, whilst at higher temperatures problems can be caused by ash softening. Source

That's 1470 to 1650 F
 
1 - 20 of 38 Posts
Top