Heating Waste Tank
I'm seeking information on how to heat the grey water tanks on a commercial mobile kitchen unit. It's not an Airstream so the tank is simply located under the floor with its' bottom flush with the bottom of the chassis frames. The first logical step would be to enclose the bottom of the tank, simply framing down with, say 3", steel channels and then constructing a galvanized sheet metal belly pan. There's adequate ground clearance to permit this. Subsequently the belly pan could be insulated. It's at that point I'm wondering how to heat the tank and the discharge connection. Remember, this is a grey water tank only and it will be dumped (---to a "blue tank") at least every other day - or sooner. Temperatures here frequently drop below "0" so the problem is significant. The 40 gal fresh water tank is above the floor and the unit will be heated 24/7.
Other solutions involve spotting a "winter" grey tank inside - although that's costly in terms of floor space and it would probably involve pumping the waste from the sink sumps to the tank. The average rate of discharge is probably less than 20 gallons per day - so the daily removal of a portable tank would not be out of the question. There are no sewer connections at the site where this unit will work during the winter and fresh water is replaced via portable tanks when needed.
I would certainly appreciate any creative ideas.
2003 GMC 3500 D/A, CC, LB, 4x4 and 2000 Airstream Excella 30. WBCCI 7074