2011 Invention Awards: From Waste To Water:
The exhaust of an idling engine is at least 550°F, which is hot enough to flash evaporate the waste and thermally oxidize the organic materials. Quite simply, the device can break down anything organic that’s put into it. The process eliminates all odors, Nassef says, and the main by-products are carbon dioxide and clean water vapor.How It Works: Zero Liquid Discharge: Waste flows from the boat’s toilet to an equalization tank, which breaks it into small pieces. The material next moves into the homogenizer, a container where it gets chopped into particles. The injector pump pressurizes the material and sprays it through a nozzle into the engine’s exhaust system, where the heat cleans it. Blanddesigns.co.ukNassef built a ZLD prototype in 2004 from washing-machine parts and a five-gallon paint bucket. The current version, his 11th update, uses only as much energy as ten 100-watt lightbulbs, sterilizes waste without any of the harsh chemicals of other portable toilet-waste-disposal systems, and can be scaled up or down. In 2007 it earned a certificate of approval from the U.S. Coast Guard for marine sanitation devices.Nassef is starting with boats, but the ZLD has the potential to work in just about any vehicle with hot-enough exhaust and a toilet. He’s drawn interest from RV manufacturers and the U.S. military, which often resorts to burning waste with jet fuel at a total cost of $400 per gallon at its forward operating bases. Another promising market is airlines, which could plug the ZLD into existing toilets, allowing some planes to shed up to 500 pounds of wastewater weight over the course of a flight.
via 2011 Invention Awards: From Waste To Water | Popular Science.
Not only is the development itself remarkable – but approval by the Coast Guard in three years seems pretty prompt.