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Temperature Drop across pipe

Temperature Drop across pipe

Temperature Drop across pipe

(OP)
All,

We have a gas at 280F. This gas is  sent to Amine unit for further polishing.If the amine unit is approx 2 miles downstream would there be any temperature drop

Any help will be appreciated

Regards
sp

RE: Temperature Drop across pipe

Is there any reason to think that the temperature wouldn't drop?

My hot water heater is only 40 ft from my shower and there's a temperature drop.

TTFN

RE: Temperature Drop across pipe

Yes, there will be a temperature drop. The size of the drop is dependent on lots of things.

Insulation.
Velocity
Gas Properties
Ambient conditions

To name a few.

RE: Temperature Drop across pipe

There will certainly be a temperature drop, especially if the pipe is not insulated.  If you need to maintain the 280F, you will have to insulate and add heat tracing.  Of course I don't know the system and the chemistry may not allow this, but you could calculate the temperature drop and increase the 280F to whatever you need to have the right temp at the amine unit.

By the way, older homes are built with copper water piping, which is a pretty good conductor, so don't expect as dramatic a drop as from your hot water tank to your shower.

RE: Temperature Drop across pipe

(OP)
All,

Thanks for your assistance,

Is there a theorotical method by which I could be able to calculate the temperature drop across the length of the pipe.
Any suggestions welcome

Regards

sp77

RE: Temperature Drop across pipe

The basic convective heat transfer equation of Q=h*A*delta_T, where:
>> h heat transfer coefficient
>> A area

That said, your piping insulation, fluid flow rate, solar load and ambient air also need to be factored in.  Overall, there's no simple closed-form solution, but there are thermal analysis programs that could probably do the numerical analysis.

You can potentially set up a lumped parameter model of the pipe and at least get a reasonable swag.

TTFN

RE: Temperature Drop across pipe

the answer depends on your pipe / mechanical design, doesn't it, so you'll have to provide some essential details for the group to sort thru...

RE: Temperature Drop across pipe

We have a gas at 280F. This gas is  sent to Amine unit for further polishing.If the amine unit is approx 2 miles downstream would there be any temperature drop

If the pipe is relatively well insulated, then the process follows that of a Fanno line.

RE: Temperature Drop across pipe

It should be a fairly straight-forward heat-transfer problem.  You'll need to figure out what your average or minimum ambient temperatures are- perhaps ASHRAE handbooks would have that info.

RE: Temperature Drop across pipe

"chemical engineering Vol 1", by Coulson & Richardson (university of Swansea, UK)can help you out with all sorts of heat transfer calculations.

You might wanna look on www.tycothermal.com (a.o. supplier of Raychem heat tracing) as well.

regards

RE: Temperature Drop across pipe

If this has any influence on the design (pressure and temperature changes) then i would recommend that you get a qualified person to look at it. Use an in-house expert or hire a consultant.

Your questions are very "basic". How will you document and QA any calculation based on what you can read here?

Best regards

Morten

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