Natural Gas Liquid (NGL) Storage Industry Codes 1

[RRE]

What is a spec (API or other) that would define the requirements to satisfy REGAGEP (recognized and generally accepted good engineering practices) for natural gas liquid storage (NGL)? I am aware of a spec such as API 2510 (Design and Construction of LPG Installations) that is good guidance for LPGs. Is there a similar spec that may be used for NGLs??

I am struggling with standardizing our various NGL facilities (bullets, loading, etc)that process and store NGLs since they were designed/constructed by many fabricators or engineering firms. I am looking to ensure consistensy in our existing facilities so that auditors/regulators can find similar design meeting REGAGEP.

 

[Duwe6]

You are actually talking about the same thing. LPG = pressurized liquid propane and/or butane. NGL = pressurized, refrigerated methane.

Build using ASME VIII Div 1 with additions from API 2510. Perform regular, scheduled inspections using API-510. Repair using *both* NBIC and API-510. Write an in-house procedure mandating the above. Actually follow this procedure, and keep signed, dated records prooving that you are following this procedure. OSHA will pay special attention to your API-510 Inspx, maintenance, and repairs when they arrive for a RAGAGEP audit.

 

[RRE]

Duwe6: Thank you for the response but I contend that NGL is not refrigerated methane, but rather a distillation cut that includes C2 through C5+ instead. As matter of fact, NGL may be classed as a "demethanized liquid". Also, the vapor pressures (expressed as Reid VP) follow two different specs: ASTM D-323 for NGL and ASTM D-1267 for LPGs. My concern with using API 2510 for NGLs is that it may be an overkill. Am I off?? Comment??

Following API 510 for inspection is spot on. Thanks

 

[Kiwi2671]

RRE,
Never heard of NGL but we are currently building a $14 billion LNG (Liquified Natural Gas) facility.
Is NGL just another name for it or a totally different substance ?
Regards,
Kiwi

 

[DSB123]

api620 for storage Tanks!!!

 

[RRE]

Kiwi2671: NGL is a mixture of C2 through C5+ that for our operations, is a product of a cryogenic distillation process (usually thermoexpanders) in gas plants. The overhead from this tower is residue gas, mostly methane, that is used/sold as sales natural gas. The bottoms from this tower is typically our NGL product that must meet certain specifications of vapor pressure, total sulfur, etc. In some plants, this stream can be further distilled into LPG (mostly propane and butanes). NGL is not LNG. LNG is different mixture of mostly light ends (methane) that is refrigerated. NGL is delivered from the bottoms of our tower at a pressure ~450 psig.

 

[Duwe6]

I was wrong on the methane, looks like. Feel that I am correct on Sect VIII Div.1 and API-510. Still think that you need to write a company procedure that includes these 2 codes, and states how much, or how little, of API-2510 your site will use.

This will put you in the position of having evaluated your risk, addressed that risk, documented your response, and have a written practice *that you are following*. It is critical that there is a trail of reports that show that you are following your site procedure.

The procedure needs to use the inspection intervals of API-510, sepecially the 10-year internal Inspx. Also make aprovision to use RBI when internal Inspx is difficult or not warranted.

 

[maddocks]

We always work to ASME Sec 8 Div 1 for these types of storage vessels. Just for argument sake, I often define the C2-C4 mixtures as LPG and the C5 plus mixtures as either NGL or more appropriately just stable condensate.