SpudFiles

Ive got this project for chemestry, and the project is: cook an egg using ~20g of ethanol. A small crappy alchohol burner is provided.

now the rules are, we can build our own burner, and can pretty much do whatever, so long as we use the 20g of fuel provided.

my current idea was to take a small jar, fill partway with water, add the egg (higher pressure=higher boiling point) put the jar above the burner, and make some kind of super insulated enclosure.

since i havent started building it, any suggestions or completly different designs?

An efficient and easily made burner/stove;

http://zenstoves.net/BasicPressureBurner.htm

Found here (tons more)

http://zenstoves.net/LinksGeneral-DIY.htm

The most effiecient way of heating water I've seen;

http://images.google.ca/imgres?imgurl=h ... s%3Disch:1

Perhaps you could combine the two with your "pressure cooker" idea?

More links; (I must be bored. )

http://www.freewebs.com/homemadealcohol ... tstove.htm


Good luck, report the results.

The burner will be simple to make. A small glass jar with a metal lid and a fabric/string wick which can be lit. Then a jar which will barely fit the egg (to use less energy to cook the egg)- perhaps even shaped to fit more appropriately. Use the thinnest walled chamber which is safe/practical. Or if you need more heat, look on instructables for things like this:
http://www.instructables.com/id/Cool-Li ... ture-Stove!/

Instead of trying to pressurize the egg for a higher boiling point (which could bugger your egg, and wouldn't be much more efficient) add some (non-toxic) impurities to the water such as salt to raise the boiling point so all the energy isn't lost to the water during latent heating.

Use a shroud around the egg container/burner and keep it covered (ideally, a vacuum is the best insulator) but allow ventilation and airflow so the flame isn't choked.

Is ethanol the only source of energy you have to work with?

Why not be a proper arse'ole and make a burner that drives a steam engine which turns a generator which powers and electric heating element

Somewhat like the Kelly Kettle, and like inonickname said, you want some sort of shroud to keep the heat in. I would suggest a similar metallic wrap, like something between VERY thick Al foil and VERY thin sheet metal. wrap that around, with some holes at the bottom for ventilation, and you should be good.

If you want better heat transfer to the cooking chamber thing, make it out of metal (Aluminum is preferred) and attach radiator style fins on to it, where the flames will be "flowing" to increase surface area. You may want to look at the "Jetboil" backpacking stove (REI sells them, and there are quite a few photos online, but I couldn't find any diagrams online) for inspiration.

I am with them on avoiding building up pressure. Superheated water is not something to mess with. Just stick to copious amounts of salt, and good insulation, and good conduction.

Lentamentalisk wrote:Somewhat like the Kelly Kettle, and like inonickname said, you want some sort of shroud to keep the heat in. I would suggest a similar metallic wrap, like something between VERY thick Al foil and VERY thin sheet metal. wrap that around, with some holes at the bottom for ventilation, and you should be good.

that could work, but I would suggest something else. Instead of using foil for insulation, use something like this

that is a piece of ceramic wool probably the best high temp insulator available I build my foundry furnace from that and I can tell you my furnace stays hot enough to cook in for at least 7 hours after shutdown

this stuff is usually only available on huge rolls but sometimes you can find small pieces on ebay that won't break the bank like this one
that would be perfect

of coarse this is only if you have a budget for this project if $17 is too much for this project then go with the foil

Are you allowed to cook the egg outside the shell?

Hotwired wrote:Are you allowed to cook the egg outside the shell?

It sounds like a "cook a boiled egg" kind of thing. I guess you could use less energy if it was cooked out of it's shell without the water.

thanks for all the help guys, as far as i know, we have to use the ethanol, but we might get to build our own burner. ive got tat class this morning, ill ask more questions there

You don't need a pressure cooker or to boil the water. In fact, you don't want to boil the water since the phase change will absorb energy (and you're on an energy budget!).

Just heat it to 180 or so. Thermal losses will be lowered and no penalty for phase change in the water. Eggs WILL cook at such temperatures.

Oh, and use the absolute smallest amount of water you can get away with.... Hmmm.... I wonder what would happen if you skipped the water and just put the egg over the flame?

Hmmm.... I wonder what would happen if you skipped the water and just put the egg over the flame

I guess that the reason why eggs are boiled in the first place is because boiling limits temperature... so at 95 deg C everything is the way it should be... but at higher temperature protein inside the egg will turn into something looking more less like burnt meat (and it's quite possible taht the egg will crack/'explode' in the process)

Just thinking outside the box, why not use the ethanol to fuel a combustion that would fire the egg fast enough to boil it through air friction

I actually once read an article that discussed the cooking temperature of eggs. It turns out 100c is not the best temperature to get the best tasting egg. Slightly less actually makes it much more tender and all. It has something to do with the temperature at which different protein strings do their thing, and by 100c, they are all done with. Still, keeping the water at a constant temperature below 100c is going to be challenging.

@D_Hall, burning egg shell stinks really really bad. My sister (in a stuper) didn't use enough water to boil some eggs and guess what, stunk up the entire house, what a douche bag !

POLAND_SPUD wrote:I guess that the reason why eggs are boiled in the first place is because boiling limits temperature... so at 95 deg C everything is the way it should be... but at higher temperature protein inside the egg will turn into something looking more less like burnt meat (and it's quite possible taht the egg will crack/'explode' in the process)

I'll buy that.... But I'm gathering that this is a contest of some sort. IE, I'm guessing that there's some metric by which the winner is selected other than taste. I mean, is there any requirement for the egg to taste good or is it just "First guy to get an egg that doesn't run wins?"