Here we go again...this idea re-surfaces about every 10 years.
It was first tried in RVs about 30 years ago...and it actually seemed to work pretty well....at least till the animal fats in waste began clogging up catalytic converters and mufflers. There was also one more minor problem: unbearable odor
that gassed everyone in vehicles up to a quarter mile behind an RV equipped with this system. So...it didn't last long.
Several other would-be inventors have tried to make it work in RVs with no better success...but the first--the ONLY--attempt to put on a boat was about 15 years ago. Some Europeans put one on a muscle boat...it worked, they put it on the market for a couple thousand bucks. What THEY overlooked was, very few boats except muscle boats have dry exhausts...and wet exhausts don't hot enough to incinerate anything. Plus, there was still that pesky odor problem and those darned animals
fats. It was a short-lived venture.
Now, here we go again... This guy CLAIMS to have solved
the odor problem, but doesn't address the animal fats (it takes some time or some VERY heavy toilet use for those build up enough to start to cause problems, so he may not even be aware of it yet). So while it may work on a RV, it still wouldn't work on most boats because most boats have wet exhausts.
The most creative use of engines IMO was the person who first thought of strapping a pot roast to the engine block of an RV...400 miles later, dinner.