I have a Kleentec heated acqueous parts washer. It uses a a water based cleaning solution with rust inhibitors and corrosion inhibitors so it is safe with aluminum and ferrous metals. It heats the solution to 110 degrees F and circulates it with a pump through a couple of filters. The cleaning solution is relatively benign although it is still tough to dispose of because it will contain all kinds of bad stuff after you have used it for a couple of years. It cost me a lot but I have had it for many years. Still on the first batch of solution although it is getting pretty weak. I replace the filters every 6 months or so depending on usage.
Pagosa Springs, CO