Sean Murphy

Ernie Wisner wrote:Does it have to be a single distill? you could use small diameter pipe and do a high heat distill then An evap and distill. by the end of the process you should have about as pure water as you could get. it should do it well under 30 min. if you balance your feed speed you should be able to pull live steam off the pipe and recondence it into an evaporation retort then recondence that into your product. A small pocket rocket should give plenty of heat to perform both operations with little of no slowdown.

I'm not sure I follow... are you saying double distillation? What do you mean by an evap and distill? I was thinking just boil it all once, capture the vapour and condense it into another vessel. Do you think it would make a difference whether a low volume of water is being slowly dripped onto the rocket or a large volume is surrounding it? Also, would an open top with a pot sitting on top of it be better or worse than another cylinder over the top, with a pot sitting on that? And yeah, I'm hoping a pocket rocket will suffice... it's an utterly enormous amount of energy though. How big do you think it will need to be? Tin-can size or much bigger?

C.J. Murray wrote:Start by looking at this: http://www.oldjimbo.com/survival/kellystove.html

And this guy's videos. I think he has posted here before: http://www.youtube.com/user/bs4872

Hmm... bs4872's water heater is just that, a large volume, low temperature water heater. I'm looking more for a low volume, high temperature boiler. I guess there isn't much of a design difference though, so it does show promise. The Kelly Kettle seems a little less practical... just not large or powerful enough. It doesn't use the "reburn" that makes rocket heaters so powerful.

However, I did find this somewhat inspiring:

Still a lot of research to be done. There are a lot of ways this could go.

Hey guys, I'm thinking about a university project I'm going to be working on in a few weeks where I have to purify 1L of water in 30 minutes with a budget of $100. The water is going to contain soil, bacteria and salt. Soil and bacteria are pretty easy to take care of but the only real way I know of to remove salt is distillation, which obviously requires boiling. Unfortunately, boiling a litre of water DRY in 30 minutes would take an enormous amount of energy. Even a gas stovetop probably wouldn't be enough. But then I remembered reading something about rocket mass heaters and thought it might have a chance. So I've been reading a lot about them in the past few hours and thought I'd post here for some advice.

I think this has potential after reading page 16 of this document (boiling 2.5L of water in ~25 minutes): https://www.engineeringforchange.org/static/content/Agriculture/S00069/Rocket%20Box%20Design%20Document.pdf

But as for a design, I'm pretty much clueless at the moment. All it really needs to be is small and as hot as possible. Efficiency is pretty much irrelevant but it would be nice I guess. Any tips?