Cryo system design.
Cryo system design.
(OP)
I am new to cryogenics. I have been singled out to engineer a system to convert methane gas to liquid. Create storage, and transfer the product to new locations. I have lots of experience in Liquid propane, so the concept of cryogenics is not totally foreign, although condensers are.Any help in finding supplies,support and engineering would be very helpful. I plan on trying to attend the classes in Colorado this year, does anyone have any comments on that ? Thank you in advance.
danthemeterman
danthemeterman





RE: Cryo system design.
I've designed smaller LNG plants and it was great fun. Finding the physical equipment is tough, loading pumps being among the hardest.
Is the training at CSM?
RE: Cryo system design.
danthemeterman
August 4-7, 2008
27th Annual Cryogenic Engineering Summer Session Short Course
Sponsored by the Cryoco, Inc.
The 27th Annual Cryogenic Engineering Summer Short Course
RE: Cryo system design.
You're asking a pretty broad question. It sounds like what you're trying to do regards system level design. For that, such things as ASME B31.3 piping code and ASME BPV for vessels apply. Since this is a flamable, NFPA codes also apply. Large structures or buildings need to comply with IBC. Basically, the same kind of industry standards that apply to any process system will also apply here.
You might also consider locating equipment suppliers and/or engineering consulting perhaps through ThomasNet.com
If you can be a bit more specific about what you're trying to do it would help.
RE: Cryo system design.
danthemeterman
RE: Cryo system design.
RE: Cryo system design.
RE: Cryo system design.
NFPA 59A
ASME B31.3
NFPA 70 aka NEC (for classified locations)
ASME BPV Sect VIII Div 1&2
Start researching
gas compressors
heat exchangers
refrigerant schemes like Linde cycle, Joule-Thomson cooling, cascade cycles, mixed refrigerants, and more
Good luck. I just got out of the business of small LNG plants. It's really interesting, but it ain't easy.
RE: Cryo system design.
The project just hit it's first wall, a major hurdle. There is more startup capitol needed than is currently budgeted. That being said, I was hoping to put together a package form scratch. I called around and found a firm that does turnkey, and the funds are not there. Hoping to use my common sense and previous experience, is also not helping at this time, and I have to believe there may be a considerable amount of demand for the equipment available.
RE: Cryo system design.
RE: Cryo system design.
RE: Cryo system design.
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I was looking at 50,000 gallons/day at a cost of $10MM US.
The gas had about 3% ethane and less than .5% of Butanes plus. CO2 was over .5% and water was 7 lbs/MMSCFD.
If you want to use in motor fuels you'll have some problems as the ethane must be under 2%. Bad rule, but thats the facts.
RE: Cryo system design.
*WARNING - OUT OF THE BOX THINKING AHEAD*
Better yet, make a deal with some company that uses the LIN and stick the system on their site! They use the gas, you use the refrigeration.
RE: Cryo system design.
The last LIN I sold was in 2003 and it was $.60/gallon with $3.00 gas. I'll bet its $1.00/gallon.
Our capital was $.12/gallon, Operating cost $.07/gallon, and energy use $.09/gallon, under $.30/gallon.
I could get it lower but product spec's added to costs.
RE: Cryo system design.
check your numbers again. 200 gallons per day methane times 1.2 gallons LIN per gallon of methane gives just 240 gallons of LIN per day or just over 7000 gallons of LIN per month. Being this is a roughly 700,000 SCF per month usage rate, I'd guess the deal on LIN could be quite good. I've seen LIN as low as about $.25 per gallon for large customers, though I don't think this is quite that large. Still, it's a good sized usage.
Look at it this way, the cost for a gallon of methane is going to be about 60 cents for the nitrogen plus cost of equipment. That may or may not be in the ball park of what's needed. I'll wait to see what Dan says.
RE: Cryo system design.
RE: Cryo system design.
LIN is liquid nitrogen, yes.
I calculate that it takes 1.3 moles of LIN to get 1 Mole of LNG. I use moles because it makes it clearer than gallons since both the LIN and LNG will be measured by mass then converted to a gallon based on a contract term and not always some published density term.
There is a small packager already in my link. Also look for this:
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This is out of the box stuff. There is a working Model in Denver. I think Cryco sold off the division that has it.
As for doing it your self on a small scale, I'd look at a small LIN plant that you use the LIN to make LNG and sell the O@ to bay most of the bill on the LIN plant.
LIN and LNG storage tanks are very expensive, but available used. Getting the aluminum heat exchangers will take some work.
RE: Cryo system design.
Is your feed gas really a pure methane, or is it a methane rich gas with significant impurity? Remember that some impurities can plug up your system as they freeze out (water, CO2, higher hydrocarbons, etc.) and other gases (N2, He, etc.) will hurt your yield.
RE: Cryo system design.
RE: Cryo system design.
55-65% methane, 30-35% carbon dioxide, with some hydrogen, nitrogen and other traces.
RE: Cryo system design.
a combination memebrane and amine would most likele be thge best. I'd also look at propylene carbonate and amine
RE: Cryo system design.
The other stuff might not be a problem in liquefaction of LNG. However, in terms of meeting a product specification might make some of these more problematic. For example, you might have high levels of propane with associated gas. It would not cause any real problems in liquefaction, but your end user might not like it.
RE: Cryo system design.
Thank You.
RE: Cryo system design.
RE: Cryo system design.
RE: Cryo system design.
1. If you freeze the CO2 out, you could separate it with a strainer.
2. Putting it through a large vessel where velocity is minimal might allow the frozen CO2 to drop out.
Doing either (or both) of these at an intermediate step of around -80 F means the CO2 will be solidified and the remainder will be gas. The only concern I'd have is that there would probably need to be some way of getting the solidified CO2 to form large 'chunks', large enough to get stuck in a strainer or fall out at low velocity in the tank.
This also adds some cost to the economic analysis I provided earlier of course (May 12 @ 19:11). Take a look at that again and see if the use of LIN is cost effective or not - still curious if the above cost is reasonable for you.
RE: Cryo system design.
Trying to remove CO2 in a solid phase is a patented process by Exxon, the Ryan/Holmes. Noticed I said try.http://w
RE: Cryo system design.
RE: Cryo system design.
As dcasto alluded, the CO2 will tend to freeze onto stuff rather than drop out as particulate or something.
Freezing isn't my favorite method for CO2 removal. I've also used vacuum pressure swing adsorption. I've considered using amines and a few other methods too, but they weren't cost effective on the scale I was to produce.
You might give a call to my old company (http://www.prometheus-energy.com/). I don't know if they still have capacity for any new projects, but this sounds more and more like the kind of thing I used to do.
RE: Cryo system design.