Originally Posted by Lady Franklin
Is there any way to build one where I don't have a tank of urine to empty every week or so?
I remember when researching the design of composting toilets that some of them try to evaporate the urine by running air over it before it goes up the vent pipe. Since most designs I see call for some sort of vent fan, what if one were to include the urine tank in that vent airflow? That is, the toilet would be vented to the urine tank (they're already connected through the urine diversion plumbing, but I'm talking a much larger vent pipe), and then the fan would be connected to the urine tank. If one used a long flat tank with air-in and air out on opposite ends it seems to me you'd get at least a little evaporation in the process.
What do you think?