Rockets and human wastes have an uneasy relation, with the latter’s flushing in the midst of space being more of an unwelcome complication. To that end, in a conventional scope, human wastes are shifted to disposable cargo vehicles that get unceremoniously burned up on the space shuttle’s re-entry into the earth atmosphere. But what if such ‘sustained’ supply of organic matter can be synthesized for some greater cause? Well, a group of scientists at the University of Florida (UF) have put forward their project that can seemingly solve the woe of human wastes in space, by converting them into usable fuel for rockets.
This resourceful endeavor was partly fomented by NASA’s goal of constructing a permanent human base in Moon by 2024. During such long term missions, along with the busy scope of shuttling back and forth between Earth and Moon, it is pretty impractical for the transporting rockets to have weighty cargo containers laden with waste. Moreover, dumping the waste on the Moon’s pristine surface is also not really an ethical option. Fortuitously, the researcher duo of Pratap Pullammanappallil and Abhishek Dhoble (now at University of Illinois), have come up with a nifty solution that allows the production of methane from the waste materials.
Aided by NASA, the scientists were able to run their tests on chemically produced human waste that was salvaged from a variety of stuff, like food waste, packaging material and even towels and cloths. For the generation of methane, they utilized what is known as an anaerobic digester process – which entails the breaking up of these organic matters into a pathogen-free composite of carbon-dioxide and methane, without the interference of oxygen. The end results showed that a substantial 290 liters (77 gal) of methane can produced on an average for each crew member for over a period of seven days.
Quite incredibly, the advantage doesn’t stop there. The aforementioned digestion procedure can also be used for a whopping 757 liters (200 gal) of non-potable water, which in turn can be ‘sundered’ by electrolysis to form oxygen and hydrogen. The oxygen can be further utilized for back-up breathing systems, while the remaining quotient of hydrogen and carbon-dioxide can be re-used for generating methane and water. As for the potentially (and literally) far-reaching beneficial effect of this tech, this is what Pratap Pullammanappallil had to say –
We were trying to find out how much methane can be produced from uneaten food, food packaging and human waste. The idea was to see whether we could make enough fuel to launch rockets and not carry all the fuel and its weight from Earth for the return journey. Methane can be used to fuel the rockets. Enough methane can be produced to come back from the Moon.