Adequacy check of existing relief devices (2No. 8T10s set @17.7 barg; conventional)for LPG storage spheres confirms they are grossly oversized in the event of governing external fire scenario.
Using API model I calculated relief load of 79,833 kg/hr. Relief fluid z factor is around 0.6691...
@georgeverghese (Chemical) - Kindly advise on how to contact you privately (drop some clues, LinkedIn profile, etc.). I really need to pick your mind on a compressor issue.
Regarding flare stack sizing using the simple approach in API 521, has anyone accurately determined the linear equation for Figure F.1 - Flame Length vs Heat Release - Industrial Sizes & Releases (SI units) and the nonlinear equation for Figure F.3 - Approximate Flame Distortion Due to Lateral...
We are currently designing a pressure regulating/let-down package for a natural gas pressure regulating and metering station (RMS) that consists of an active regulator, a monitor regulator and a safety shut-off valve (SSV) connected in series - in the direction of flow the SSV comes first, then...
So I am developing a first-principles model involving the combustion of a natural gas fuel source containing both nitrogen and CO2.
And even though this is quite basic, I have struggled with writing a balanced equation for the combustion of this fuel source with excess air, especially with the...
We are currently engaged in a conceptual study for a Natural Gas Pipeline Gas Turbine Driven Centrifugal Compressor Facility.
The overall compression ratio is 2.614. Even though the discharge temperature is below the limits commonly imposed for per stage, I am considering 2 preliminary concepts...
In using Aspen Flare System Analyser can anyone share how to force a certified rated capacity to flow from a fire case relief valve instead of the required relieving load. I am evaluating the flow properties of an existing flare system pipework.
In trying to determine an accurate latent heat of vapoourisation for an LPG tank exposed to an open pool fire, I recently came across this procedure (see link below) to determine the latent heat of vapourisation for multi-component mixtures using Aspen HYSYS.
Title: Determine Latent Heat for...
@MortenA
I understand your point of not grossly oversizing the flare network.
In a flare system rating study, Will you recommend forcing Aspen Flare System Analyser to use the rated flow or leave it to run on the required relief load.
Here goes...
Having sized a fire case (Max. Accumulation = 1.21 x MAWP) relief valve using API 520 equations.
I selected a preliminary API 526 orifice size; in this case a "T".
I obtained the manufacturer's actual orifice area (which was larger than the API 526 orifice area) and the...
@apetri
I work in the gas processing industry actually. But I am building a mathematical model of a natural gas heater with Matlab.
Thank you for the great insights provided. I can tell you have a solid background in Thermodynamics. I will check out "The Properties of Gases and Liquids...
@pmover
I can't thank you enough for all your help.
I really appreciate it. Realized I was executing the math wrongly in excel.
I have since corrected it and the result is the same as yours.
Thank you so once again.
@apetri
Thank you very much for the additions. Indeed, I had initially...
Hello @pmover,
I can't thank you enough for your clarification.
Just so we can put this matter to rest please find some time to go through the attached excel file.
It is an attempt to calculate the molar volume Vc for a hypothetical three-component mixture of methane, ethane and propane...
The Original Lee-Kesler Mixing Rules.https://files.engineering.com/getfile.aspx?folder=109a8381-370e-498c-a07c-69b80d7e86ab&file=Lee-Kesler_Original.bmp
I'm currently applying the Lee-Kesler EoS to calculate enthalpy departure but I have run into problems applying the mixing rules mostly because different approaches are used in literature.
All the other formulas (Zci, vci and w and Pc) are straightforward except the critical molar volume (Vc)...
What is the best approach for sizing Pressure Safety Valves for 4No. LPG tanks connected to each other by a Pressure-Equalization line. The balancing line from each sphere connects to a common header. Each line from a Sphere has a Fail Close on/off ball valve which is to remain open during...
@The Obturator - Thank you for the great effort. As we all agree by now. As outlined in API 520 Table 4, the relieving pressure = Pset (gauge) + allowable overpressure (gauge) + barometric pressure. Allowable overpressure = Maximum Accumulation (1.XX x MAWP) - Pset. Glad you re-produced my...
Thank you @The Obturator. Will be waiting patiently to hear from you when you have any new information.
Would be interesting to hear the views from other subject matter experts when faced with such a case.
@The Obturator (Mechanical)...thank you very much as ever.
Sorry, the liquid depth is 2.130 m. Also, the vessel operates between 0.3 barg to 0.6 barg.
Yes, normally, PSV is set = vessel MAWP. It may also be set below the MAWP in accordance with API 520.
Indeed, API 520 defines the upstream...
