Does anybody know what the specific heat (capacity) of THC is?
I found 1.6 joules/g but it doesn’t say for THC, CBD, etc, only for “hemp”
I can get this measured precisely if someone wants to pay to find out. DM me.
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Yeah that 1.6 j/g is for like compressed hemp biomass like fibers and particle board and such. For its like flame resistance profile.
Not sure why you want this specific piece of information. But you can probably use a home made calorimeter to check what you already have. Known mass, known starting temp, put in the calorimeter - wait for temp to reach equilibrium, write down elapsed time. And calculate from there.
Of course - it would be your specific THC, including any impurities, but still. 
I looked at all my THC notes from the last decade and it appears I never did this test. 
I’ve got notes on vapor pressure, boiling points, melting points, solubility… but not this. Sorry.
Perhaps someone will take @MagisterChemist up on their offer? 
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Depending on how accurate you need to be, I believe edible oils such as olive oil are close-ish to THC. Something in the range of 1.9 or thereabouts.
It wouldn’t be all that hard to test, depending on how accurate you wanted to be.
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I’m having a heat jacket made and the engineer asked me what the figure is to see how many watts/sq in we need.
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Damn engineers…
Are you decarbing?
If so they asked the wrong question…
Don’t they know
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I’m trying to heat a stainless tank full of decarbed viscous product from 60c to 130c over the course of 4-6 hours
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It sure does.
1.9 is going to be close enough for estimation purposes. I think that’s what I used for the termo calculators I published forever ago, and no one has ever complained.
I usually use something over that if I want to be really conservative, but your engineer also needs to consider that “decarbed viscous product” is a hella vague description and could have all sorts of unquantified shit in it, making the heat capacity of pure THC rather meaningless.
Hell, I’d rather know viscosity at various temperatures than heat capacity, but I’m weird like that.
Of course, heat transfer into your fluid is going to be significantly affected by the mixing parameters, level of insulation over or around your heat source, and dT between the jacket and your fluid.
Why 4-6 hours? That’s an odd number. It’s not overnight, and it’s an awkward number if it’s first shift kicking it on for second shift.
Making heat is about the simplest and cheapest (capex, not opex) thing we do. Overkill the fucker then PWM or otherwise throttle it down.
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I am interested in these figures as well as the melting point (64c?) and some other things. We are going to set up an experiment to try to determine the heat capacity of our concentrate at different stages in the process.
I’m scaling from a smaller jacketed glass tank to a 120L stainless tank.
We are limited in how much current we can pull in this facility so every bit counts.
This heat jacket can be either 1 or 2 watts per sq in and can be 240V or 120V. I’m looking at around 5000w
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Sounds like you’re using band heaters of some description. Any time I’ve looked at them, they’ve been the same price regardless of the voltage or power density.
I’d go with 2w/sqin at 240v. You can always turn them down, if 1w is too low you can’t turn it up.
This will be a silicon and rubber jacket cut to the shape of the tank and glued on
You could also consider… using natural gas fired water based heating on a jacketed container. When I had to go big - I moved away from electricity and over to natural gas.
Biggest I ever had to do what a 60,000 gallon container in Kentucky. No way was I doing that with electricity.
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I’m not quite that big yet.
Maybe in the future, for a different configuration of something similar that would solve a lot of problems.
Agreed.
From a pure $/j perspective, natural gas is about 1/2 the price of electricity here.
Of course, our electricity is almost exclusively from hydro and other renewable resources, so there are other considerations to take into account, but if you need to make heat, setting dinosaurs on fire is a pretty cost effective way of doing it.
I prefer to try to limit heat flows as much as possible, but that’s not viable everywhere - sometimes you have no choice but to make things hot or cold.
Utilizing waste heat can be useful as well. Chillers make lots of it.
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Oh yeah. At my Kentucky facility we had all kinds of cooling towers and such as well - that in different parts of the year (aka winter) would be rerouted to assist with heating the facility - so that heat could be reused in different ways.
And by using the cooling tower - we were heating up the environment, but were not spending electricity on chillers (although the tower did have a fan, but much less than some other options…)
So many things happening out there. Sustainability - what is physically possible with available utilities, etc. etc. etc.
In Michigan now EGLE is controlling more - so you can get popped for all kinds of things that in the past they didn’t seem to care about.
Combine that with a serious lack of electricity in many places (sounds like @drake is having that issue…) and coming up with alternative means is important.
Some places I recommended solar panels - because they were cheaper than trying to get the local utility to expand capacity.
Some places I tell people to switch energy source… one place they had natural gas but not electricity (how? the fuck does that happen…) so we did generators.
Always something new in cannabis.
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Agreed 100%.
Being more energy efficient means our opex goes down, we’re nicer to the environment, and we can do more processing without having to beg and bribe the utility to install a bigger transformer for us.
Every time energy consumption comes up I feel bad for anyone relying on cold solvents and thermal solvent recovery methods.
A quick very conservative back of the envelope suggests that the over-built and underutilized system we’re working on should be consuming not more than 12 kWh per kg of produced CBD isolate. Once everything is fully online it should be closer to 4 kWh per kg.
It’s barely possible to chill alcohol to -20° with that energy budget, let alone evaporate it and then condense it.
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