First Brewing Mishap

So today I brewed what was to be my last extract beer (got some new equipment for Christmas to go all grain). Anyway one of the new pieces of equipment was a wort chiller. I decided to use it today on my last extract batch. After the wort finished boiling, I was going outside to chill it (needed to hook up the chiller to my hose). Got out on the front porch and started down the stairs. Needless to say I slipped on the first step and poured BOILING hot wort all over myself. It was not a fun experience at all. I still have ice on my arm and it's KILLING me. Luckily, no blistering so I think the burn could have been worse. As soon as this happened, my first thought was "I have to post this on HBT". There I was in total pain, before I even ice my arm, shoulder and head (yes, head) and I'm thinking to myself how I need to post about this. Anyway, moral of the story is be careful with hot wort....it hurts to get burned!

Hope you are OK. You really need to get one of those adapters for your kitchen faucet to took of a garden hose fitting.

Yikes! Were you able to salvage any of the beer?

Lord have mercy! Another lesson of the day: Don't carry 5 gallons of boiling wort down stairs. I could picture that happening every time.

Ooww! Maybe run your hose inside and drain it in the sink or tub?

Beer was totally wasted. And it was only 2.5 gallons. Still though....

If I brew in my kitchen, I run the hoses right through my kitchen window. No way am I even attempting to carry boiling wort outside. Not after spending a month in the hospital and having a skin graft.

you should really look into some alternative ways to cool your wort.

one idea: get half a dozen ice making bags and fill them with maybe a 1:4 parts vodka:water ratio, seal them completely, lob them in your freezer for a few days before you boil. the alcohol has the effect of lowering the freezing point of the liquid below that of water giving a greater temperature differential between the two substances.

in short the greater the temperature differential between the two substances causes a greater urgency to create a thermal equilibrium, thus reducing the temperature. for greater effectiveness, use a bit of clear nylon fishing line and anchor some of the bags with heavy washers, so they are inserted vertically, rather all floating on top!

Just an idea, possibly less painful than what you just went through!

but just DONT forget to sanitize!!!

Bigniall666 said:

you should really look into some alternative ways to cool your wort.

one idea: get half a dozen ice making bags and fill them with maybe a 1:4 parts vodka:water ratio, seal them completely, lob them in your freezer for a few days before you boil. the alcohol has the effect of lowering the freezing point of the liquid below that of water giving a greater temperature differential between the two substances.

in short the greater the temperature differential between the two substances causes a greater urgency to create a thermal equilibrium, thus reducing the temperature. for greater effectiveness, use a bit of clear nylon fishing line and anchor some of the bags with heavy washers, so they are inserted vertically, rather all floating on top!

Just an idea, possibly less painful than what you just went through!

but just DONT forget to sanitize!!!

Click to expand...

Apologies if this comes of as quibbling, but I believe a pound of frozen ethanol will actually do a lot less cooling than a pound of ice. The freezing temps of alcohol are indeed lower, but the enthalpy of fusion is only about a third of what it is for alcohol than for water. Most of the heat absorption you're getting from ice isn't from the temperature change, but rather from the change of state from solid to liquid.

In any case, either option is better than carrying a bucket of boiling liquid down stairs!

Skin seems fine, no blistering. Just hurts like a biiiotch

MalFet said:

Apologies if this comes of as quibbling, but I believe a pound of frozen ethanol will actually do a lot less cooling than a pound of ice. The freezing temps of alcohol are indeed lower, but the enthalpy of fusion is only about a third of what it is for alcohol than for water. Most of the heat absorption you're getting from ice isn't from the temperature change, but rather from the change of state from solid to liquid.

In any case, either option is better than carrying a bucket of boiling liquid down stairs!

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its not a pound of frozen ethanol firstly, in the right ratio solidification does not occur, think of homemade ice packs for injuries, the point of adding the vodka is so that the solution inside will not solidify, but reach much lower temperatures than just dropping ice in.

we used a similar method but using di-isopropenol to rapidly cool cell lines destined for a good long sleep, the di-isopropenol is kept at -20 degrees C, this rapidly freezes the vials contained within, and prevents DMSO from killing the cells.

thermodynamics is not my strongest subject but unfortunately i have to do my final year project in it this year.

Bigniall666 said:

its not a pound of frozen ethanol firstly, in the right ratio solidification does not occur, think of homemade ice packs for injuries, the point of adding the vodka is so that the solution inside will not solidify, but reach much lower temperatures than just dropping ice in.

we used a similar method but using di-isopropenol to rapidly cool cell lines destined for a good long sleep, the di-isopropenol is kept at -20 degrees C, this rapidly freezes the vials contained within, and prevents DMSO from killing the cells.

thermodynamics is not my strongest subject but unfortunately i have to do my final year project in it this year.

Click to expand...

Certainly alcohols are used for quickly dropping the temperatures of cells for freezing, but this is a different kind of problem. Here, the question is just about the capacity to absorb heat, no? Perhaps I'm misunderstanding things, though.

Water's heat of fusion is 334 kJ/kg, and ethanol's is 109 kJ/kg, and their specific heat capacities are 4.1 and 2.8 J/g respectively. Certainly, you get a lower liquid temperature with a 70% ethanol solution, but do you actually get more heat capacity? Even if you bring the solution down to -40º, the numbers don't seem to suggest that you would. Am I missing something?

MalFet said:

Certainly alcohols are used for quickly dropping the temperatures of cells for freezing, but this is a different kind of problem. Here, the question is just about the capacity to absorb heat, no? Perhaps I'm misunderstanding things, though.

Water's heat of fusion is 334 kJ/kg, and ethanol's is 109 kJ/kg, and their specific heat capacities are 4.1 and 2.8 J/g respectively. Certainly, you get a lower liquid temperature with a 70% ethanol solution, but do you actually get more heat capacity? Even if you bring the solution down to -40º, the numbers don't seem to suggest that you would. Am I missing something?

Click to expand...

I have nothing scientific to add, but I love that it seems like the longer a thread gets on this website, the higher the chance it turns into a chemistry/physics/etc. discussion. One of the reasons I like these forums more than others I've read

MalFet said:

Certainly alcohols are used for quickly dropping the temperatures of cells for freezing, but this is a different kind of problem. Here, the question is just about the capacity to absorb heat, no? Perhaps I'm misunderstanding things, though.

Water's heat of fusion is 334 kJ/kg, and ethanol's is 109 kJ/kg, and their specific heat capacities are 4.1 and 2.8 J/g respectively. Certainly, you get a lower liquid temperature with a 70% ethanol solution, but do you actually get more heat capacity? Even if you bring the solution down to -40º, the numbers don't seem to suggest that you would. Am I missing something?

Click to expand...

i think what we're both neglecting is that is its not just a simple matter of heat capacities, we also need to take into account the amount of wort to be cooled, and the amount of coolant that would be used. i think to solve this we would need to work out what the equilibrium temperatures would be for different volumes of water alone and water plus ethanol in relation to the wort, surface areas of containment vessels and also the thermal conductivity of the vessels may also need to be taken into account too.

let me see if i can find some of my old heat and mass transfer notes, i remember doing similar problems with regards to single, double and triple glazed windows lol

Watch out for the drain tube on your chiller as well. I boil mine to sterilize the last 15 minutes of the boil. Last time, I didn't have the drain tube down in the sink all the way. It was point upwards so when I turned the water on to FULL, it sprayed boiling water everywhere. I coated my arm too. Didn't blister, but hurt like hell and got really red for a few days. So, just another thing to watch out for with anything boiling. At least in my case, I didn't lose any of the wort.

Glad you're okay though!

Bigniall666 said:

i think what we're both neglecting is that is its not just a simple matter of heat capacities, we also need to take into account the amount of wort to be cooled, and the amount of coolant that would be used. i think to solve this we would need to work out what the equilibrium temperatures would be for different volumes of water alone and water plus ethanol in relation to the wort, surface areas of containment vessels and also the thermal conductivity of the vessels may also need to be taken into account too.

Click to expand...

I don't know that we're neglecting that, exactly, so much as assuming those things are constant in the comparison. Certainly it wouldn't be meaningful to compare a pound of ice in a gallon of wort to an ounce of ethanol solution in a barrel. But, for fixed quantities, do the volumes and ratios actually matter? We're talking about the amount of energy required to raise the temperature of a fixed quantity of cold stuff. Where exactly the temperatures end up shouldn't matter, no?

MalFet said:

I don't know that we're neglecting that, exactly, so much as assuming those things are constant in the comparison. Certainly it wouldn't be meaningful to compare a pound of ice in a gallon of wort to an ounce of ethanol solution in a barrel. But, for fixed quantities, do the volumes and ratios actually matter? We're talking about the amount of energy required to raise the temperature of a fixed quantity of cold stuff. Where exactly the temperatures end up shouldn't matter, no?

Click to expand...

hmmmm if we say use the following formula Q=m.Cp .dT, where Q is the amount of heat transferred, Cp is the specific heat capacity and dT is the temperature difference

we don't exactly know, while ignoring heat transfer to the environment around the boil pot or whatever, what temperature will be achieved by putting either bottles of frozen water or anything else into the wort, therefore the final temperature is unknown.

The Cp can be calculated easily and the mass just refers to the volume or the mass of the coolant which would roughly be known or is measurable.

so i suppose if the final temperature or the equilibrium temperature is unknown, can this actually be calculated?

hmmmm maybe im just talking through me arse!