4 replies to this topic

[zasa3]

Hi everybody
I want to calculate heat losses through ammonia tank roof. Our ammonia tank has a separate internal roof that is made of an insulation with holes and external roof doesn't have any insulation. Does anybody have any experience about this calculations? furthermore how can I calculate temperature profile from liquid level to external ceiling?
Thank you

Edited by zasa3, 20 August 2013 - 03:39 AM.

[srvna90]

I dont think it possible to calculate the heat ingression through the tank top roof.  You can consider it as a flat plate and calculate but I doubt how accurate it will be.

 

They usually calculate based on over all tank shape characteristics and what you are mentioning is a Suspended deck AAST which in overall will have only a boil off generation of about 0.04% of the total capacity of the tank,

[curious_cat]

what you are mentioning is a Suspended deck AAST which in overall will have only a boil off generation of about 0.04% of the total capacity of the tank,

 

per day? 

[srvna90]

Yes. Its per day.. its supposed be between 0.02% to 0.04%. If its more than that then the Insulation of the tank is bad and needs to be replaced.

[Pervaiz Rizvi]

We intend to store about 80 mt of Anhydrous ammoina in an existing tpressure vessel used for some other chemicals low design pressure 

we intend to use a refrigration system to hold tank at temp where vp of ammonia meets the design requirement of the existing vessel

Any idea of the system to use the refrigration will use ammoina

Do we put coil in the vessels ,circulate content thru a chiller ,or recylce vapour thru compressor/condenser like the Boill of gas in large refrigrated tanks what in your view would be the most appropriate method

REGDS

PEEYAR