Storage Tank Heater Sizing

[jburdettSXL]

I am working to size the proper heater for a new biodiesel tank at a refined products terminal in PA.
Can anyone help me determine the BTU's necessary to:
1. Heat a 30,000 gallon storage tank from 35F (min temp) to 75F?
2. Heat necessary to maintain heat between 70F and 75F?

My plan thus far is to move the product off of tanker trucks into the insulated tank and use a ciculating pump and heat exchanger to heat the product to a max temp of 75F. System would have thermostats in place to turn the unit off until product temp dropped below 70F, then heat back up to 75F. I don't want to install fin coils or heating tubes in the tank (I don't have an existing boiler system, and in my history those coils just become a possible failure point that you can't inspect when the tank is in service).
Pipelines to and from tank would be insulated and electric heat traced.

 

[Unotec]

Q=mCp(deltaT)*efficiency of heating media, works all the time

 

[willard3]

Hardest thing to find will be the specific heat of the biodiesel although it has to close to diesel.

 

[jburdettSXL]

For specific heat I normally use: (0.338+(0.00045*T))/SQRT(SpecGrav)

T: Product Temperature
SpecGrev: Specific Gravity
Works as a decent approximation.

 

[stanlsimon]

The question #1 is well answered. The answer to Question #2 is U*A*delta T inside-outside. This number may be less than the heat required to do the pickup in temperature unless you are in Siberia or Minnesota. But it is good to check.

By the way what kind of Biodeisel? Canola, Soy, Sunflower?.
We are thinking about building a Soybean processing plant and will eventually need some engineering.

 

[jburdettSXL]

I appreciate all the help.
Most likely we would recieve soy based -- but we are trying to build the tank and loading system to accomodate all varities. The main storage issue is the cloud point. Our first installation is being scoped in Eastern PA but may roll out at other locaitons if things work well.

 

[MJCronin]

jb..

http://www.iot.ntnu.no/users/fet/Publi-Forfatterskap/publikasjoner/Paper-JEME 5 feb 2003.pdf

Have you considered this HX vendor ?

http://www.greentechvt.com/about+contact/ArcticFoxBrochure.pdf

Please tell us about you final design and, upon which source that you based your sizing calculation

Regards

-MJC