Google tells me atmospheric air cools down by an average of 0.65degC per 100metres rise in altitude, so this is the driving force for the natural convection effect.
There is an error in your warehouse height.
This should help
https://en.wikipedia.org/wiki/Stack_effect
See if this helps :
https://www.linkedin.com/pulse/diesel-fuel-return-line-bleed-back-mike-trumbature
My guess is this check valve requirement on "fuel supply pressure recycle return line to fuel tank" is valid only when BOTH of the following are applicable
a)the return line enters the fuel...
Typically, this piping stress ratio route to allowing some exceedence on lower design temp is not used, since the actual stresses whilst in operation may well exceed what you compute in the design office. Since this is a marginal exceedence, see if the process engineer can calculate a higher...
Self venting gravity flow lines are typically sized to keep the Froude number N_Fr < 0.31 (in SI units). See equation 6-138 in Perry Chem Engg Handbook (7th edn) for N_Fr expression which accounts for liquids with density other than water - there is no viscosity term here though, so maybe keep...
Avoid high or low point piping pockets in the return lines to the main oil tank - all return lines should be free venting so entrained air or process gas doesnt get trapped at these pockets. Hydraulic flow equations wont help if these lines are pocketed.
We've not configured a backup supply for flare pilot FG for many installations. But the design requirements were to accommodate the short term safe venting of flare gas (max continuous normal operating case only) for all normal range wind speeds and stability classes in the event of accidental...
Speak to the folks at Norton or Koch in the USA who manufacture all sorts of packing for absorber / stripper columns. I dont seem to see Norton USA on Google - its all contaminated with links to China companies.
If this corrosion is internal, then you will have the same problems with above ground lines as with the old underground lines. Got salty water in these fuel grades at the source tanks ?
The quoted "min Cv" in that table of 11 for the 12inch valve implies a rangeability which far exceeds the typical value of 30, since 1875/11 = 170. Hence I would interpret the min Cv of 11 as being that for mechanical integrity and not for controllability - see footnote to those tables.
Hence...
Sizing control valves for the min flow case is an integral part of control valve selection, and often overlooked by process and instrumentation engineers. The end result is not good if ignored - poor controllability at low flow resulting in frequent shutdowns / unsafe operating conditions /...
The turndown case will also have to be accommodated, which I guess is : P1 = 82barg,P2=36bar, Q=10e3sm3/hr. The resulting Cv must be higher than the min permissible Cv as recommended by the control valve vendor. From this table, say for 12inch valve, the min Cv for the case of equal %, multipath...
This is where I got the solubility curve for N2 from
https://www.thermopedia.com/content/1138/
I havent been able to get a cross reference check ( so far) to this graph elsewhere at these high pressures. H shows a pressure dependence at high pressures.
And the z value was calculated from the...
Accounting for N2 solubility in water at 655 barg, Google tells me H = 6e-5 / MPa, where solubility of N2, the Henry's Law constant, is expressed as mole fraction of N2 / kgmole of water. Simplifying, this works out to 6.2kg of N2 dissolved / m3 of water. Add the corresponding mass dissolved in...
