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Off Shore Methanol Tank Design


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#1 mykid

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Posted 09 December 2014 - 02:11 AM

Hi all,

We have an existing Methanol Tank on a FPSO. Details are as follows:

(The design is kind of dubious)

 

Code: ASME Section VIII

Code Stamp: No

Design Pressure: ATM

Design Temp: 65C

MAWP - -

Type: Cylindrical tank

Capacity: 5 m3

Material: SS316

 

Attached is a photo of the tank.

 

Methanol will be used only during startup for hydrate inhibition.

Currently there is a nitrogen line connected to the tank. The supply comes from N2 cylinder.

There is no PCV on the nitrogen supply line. The vent connection is blinded. No PVSV installed on the tank.

 

Clearly the design is not acceptable. I have the following questions, hope the professional can share their experience:

 

1. Since the tank is only designed for atm with no MAWP details, is it allowed to have nitrogen blanketing system?  A checked with ASME VIII calculation (even though this is not a pressure vessel), the SS316 shell with 9 mm thk is good to withstand  0.9 MPa. Presumably in this case, the tank can withstand the nitrogen pressure.

 

2. It is proposed to add a pressure regulator on both the nitrogen supply line and also vent line and connect the vent to LP flare header. Proposed pressure to maintain in the tank 0.01 barg and outgoing pressure at 0.04 barg.

 

3. The N2 inbreathing rate is calculated to be 11.3 m3/hr based on the latest API 2000 equation. (Methanol pump out rate is 1.25 m3/hr).    Given that the N2 is supplied from N2 cylinders, can anyone advise the qty of N2 cylinders required for 2 hours injection? I am not too familiar with N2 cylinders, is it liquified N2 that is stored in the cylinder? THe nitrogen manifold will be maintained at 500kPAg with a PRV.

 

4. There is no PVSV on the tank. Is it mandatory to add one ? Presumably the PVSV has to be good for emergency relief. How to work out the size? There is only one spare 1" nozzle that can be used in the tank and the existing 24" manway is not a hatch. It is not known if hte tank can handle vacuum condition, will have to work out the external pressure based on ASME VIII.

 

Instead of nitrogen blanketing system , is it allowed to have an open vent with flame arrestor installed on the methanol tank without any inert padding?

Attached Files



#2 fallah

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Posted 09 December 2014 - 02:51 AM

mykid,

 

Methanol is a liquid with high vapor pressure (around 3 psia @25 C and 12 psia @60 C); then is normally stored in a pressure vessel (rather than in atmospheric tanks) with design pressure of, let say, 3-4 barg along with the N2 blanketing to avoid continuous waste of the methanol vapor through the vent. Therefore with considering the detail of the tank you submitted, appears the tank is initially manufactured as a pressure vessel (ASME Sec. VIII) but then it should be equipped with the relevant safety devices to be prepared for methanol storage in higher pressure... 



#3 AlertO

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Posted 09 December 2014 - 03:25 AM

Hi

 

First of all, you need to determine the actual MAWP of your tank. As the tank is designed accordingly to ASME Section VIII, you may estimate the MAWP from the tank thickness. After that, a proper pressure test (1.3 x MAWP) shall be performed. Then, you can start designing your overpressure protection device from this point.



#4 mykid

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Posted 09 December 2014 - 08:17 PM

Hi Fallah / AlertO,

Thanks for your reply.

The methanol tank was designed by an inexperienced contractor, therefore i doubt if the design is correct.

We have calculated the MAWP of the tank based on ASME VIII, the external pressure is good for 0.9 MPa. Therefore i believe it can withstand the low nitrogen pressure.

 

The only issue is the absence of PVSV.

There is no mentioned if the existing tank can withstand vacuum, how to set the vacuum setting if PVSV is provided?


Edited by mykid, 10 December 2014 - 03:49 AM.


#5 breizh

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Posted 09 December 2014 - 10:15 PM

mykid ,

consider this pamphlet .

Hope this helps

 

Breizh



#6 mykid

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Posted 10 December 2014 - 02:45 AM

4.4.1.4

 

As per API 2000 (old version), i don't have the latest version in hand. However believe it is still in the latest version..

 

Open vents without flame arresters may be used to

provide venting capacity for any of the following:

a. For tanks in which petroleum or petroleum products with a

flash point of 100°F (37.8°C) or above are stored, provided

the contents are not heated and the fluid temperature remains

below the flash point.

b. For heated tanks in which the storage temperature of the

petroleum and petroleum products is below the flash point.

c. For tanks with a capacity of less than 59.5 barrels (9.46

cubic meters) [2,500 US gallons (9,460 liters)] used for storing

any product.

 

In our case, since the volume is less than 9 .5 m3, API2000 allows open vents without flame arrestor. I understood that methanol is highly flammable therefore nitrogen blanketing is recommended. However it seems that it's not mandatary as per aPI 2000.



#7 fallah

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Posted 10 December 2014 - 03:43 AM

mykid,

 

Because, as I mentioned, methanol has to be stored in pressure vessels (3-4 barg); then API 2000 can't be applied for such vessels...



#8 Art Montemayor

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Posted 10 December 2014 - 12:43 PM

Mykid:

 

This important topic is one I have had to handle several times in the past - all on offshore applications, as yours is.  Therefore, I believe I’ve some background experience that should be of interest to you and, hopefully, of some help in resolving the correct and safe application of the MeOH tank.  You may already be fully aware of some of the needs and characteristics of your application, but I’ll go through them for the sake of all who read and/or participate in this thread.  These characteristics are important to note because they are related to the critical design and operation of the tank.

 

Firstly, the basic application for a MeOH tank on an offshore application combines two needs: a storage vessel and a pump feed tank.  The MeOH must be pumped downhole (usually by positive displacement pumps (Hammelmann?) that pump the fluid up to 10,000 psig or more.  Because of the critical clearances and mechanical demands on the pump, the MeOH fluid must be ultra-clean and devoid of any solid contaminants.  The operation of these pumps is so severe that their NPSH is critical and any help here (such as an N2 blanket) is a plus.  It is highly important and vital that the successful continuous pumping of MeOH at extremely high pressures always be available to the offshore operation because of the need to establish productive and required product and cash flow to service the project financing.  Hydrate control is a basic requirement that must be operational 100% of the time.

 

MeOH is probably the most volatile and combustible fluid on board an offshore platform with the exception of liquefied petroleum gases (propane, butane) - which I would fight rigorously to avoid them on board.  MeOH presents a variety of hazardous scenarios which must be addressed because the need of the fluid is vital in order to initiate and maintain hydrocarbon production.  The tank must be designed not only for servicing the pump(s), but also for receiving makeup MeOH from barges or other vessels.  Sometimes, the MeOH is put onboard with portable tanks, but this is discouraged because it involves connecting and disconnecting hoses between tanks on the deck of sea vessels and this presents a potential scenario for a spill or a deadly fire.  The MeOH tank is almost always sited on deck of the platform or ship due to its volatility and flammability.  Placing such a tank in a confined or non-ventilated space is never done.  Safety disconnect lines and valving should always be incorporated in the filling and discharge lines of the vessel to avoid any spillage or loss of inventory.  MeOH will ignite with any slight spark or ignition point - presenting a potential danger that must always be respected and mitigated with redundant instrumentation and valving.

 

The need for cleanliness in the pumped MeOH explains and justifies the use of stainless steel for the tank.  I have had to contend with carbon steel in the past and this is a feature that you should take advantage of.  Your tank seems to be a basic pressure vessel with ample shell thickness to contain the MeOH at a reasonable pressure of approximately 150 psig.  However, your photo is not clear and the heads seem to be either flat or slightly dished.  I would expect the use of at least F&D (flanged and dished) heads.  The comments submitted by Fallah are very good and should be heeded.  The tank should be rated for pressure (and vacuum) service in order to identify the MAWP and MAVP.  Any offshore installation has to be highly insured and I can almost guarantee that the Insurance company covering this operation will demand detailed specifications on all of the related equipment - especially the MeOH tanks.  There is no such “animal” as “atmospheric” design.  That is fabricator talk for stating that the owner did not specify a design working pressure nor a mechanical design and calculations for the subject tank.  They used whatever available shell material they had in the shop for the vessel.  If you did pay for mechanical calculations, then you should demand them.  In the meantime, you need those calculations - for the insurance company, the local legal authorities, and your own peace of mind.

 

As Fallah states, you basically have an un-documented pressure vessel that works best (on both a safety and operational need) with a healthy vapor pressure.  Contrary to what you infer, a nitrogen blanket does not prevent a fire or explosion.  The blanket is there to contain the fluid within the tank without allowing air to infiltrate.  As detailed above, this is exactly what you want to do in an exposed MeOH tank on the deck of an offshore vessel.  And as Fallah also states, that is within the scope of a pressure vessel - to contain a hazardous fluid under pressure and safely instrumented.  What prevents a fire or explosion is designing for such things as:

  • Filling of MeOH should be at the top of the tank with dip pipes;
  • Outlet nozzles for pump suction and draining should allow for remote automatic block valves to shut off all fluid flow out of the tank.  This is usually done from a central, protected control area.
  • Be careful and mindful that API does not recommend the use of flame arrestors on tanks.  There are good reasons for avoiding them.  This topic has been discussed in prior threads in our Forums.  However, there is always a need to safely vent any excess pressure from the tank away from the FPSO - and certainly downwind and away from any open flame or flare.  What I have done is initially pressurize the tank with N2 while it is filled with MeOH and allow it to deplete its liquid inventory as it operates.  When the liquid level reaches the Low-Low Level, the residual N2 pressure should still be positive and supplying the pump(s) with a healthy NPSH.  Pressure alarms and instrumentation should indicate if the positive N2 pressure remains in the tank or is depleted for whatever reason.  Normal control valves (not regulators) and pressure relief valves (not PVSVs) should be employed on a pressure vessel.  These valves should all be backed up by detailed engineering calculations as to worse credible scenarios and design capacities.
  • The MeOH should have a minimum of nozzles and openings.  Leakage through gaskets is a characteristic of MeOH and these should be minimized - especially the useless manway.  All external bottom nozzles should be reinforced and protected against any accidental force breaking or rupturing them.  I strongly recommend any vessel on an offshore platform be as devoid of internals as is possible, in order to avoid any ingress into a confined space for reasons of maintenance or repair.  In this case - particularly because the vessel is fabricated of stainless steel - I consider the use of a manway on the vessel not only as a potential danger, a useless expense, excess weight, but also as ludicrous.  There is no reason to enter or access such a vessel.  There should be no internals and no reason for entering - which is great news for all personnel and safety inspectors.

There are many other lessons learned that I could share on this specific topic - based on experiences working on offshore engineering projects.  I would hope that our excellent group of experienced engineers - such as Fallah - would join in with their recommendations as well.



#9 shan

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Posted 10 December 2014 - 04:15 PM

NORSO STARDARD P-100

 

19 Methanol injection (system 46)

 

19.2.2.2 Operating pressure

The storage tank normally operate at atmospheric pressure.



#10 Art Montemayor

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Posted 10 December 2014 - 07:33 PM

What Shan quotes is an out-dated and revised Revision 2 (Nov 2001) of the Norsok Process Standard P-100.

 

This standard is known for having some "holes", inaccuracies, and inconclusive information.  Proof of this is shown in the follow-up Revision 3 (Feb 2010) that improves on their "standard" of one short sentence but that still shows inconclusive and open questions as to what - exactly - is the recommended Norsok Standard regarding methanol tanks for offshore installations.

 

First, Norsok doesn't even mention an inert blanket in Rev2.  Then, on second thought 9 years later, Rev3 states one is required - including a "purge" system (that isn't defined).  We still remain without a recommended operating pressure for the tank.

 

A lot of the stuff that is found in P-100 is information well known to experienced engineers well before the standard became available.  Their recommendation for maximum fluid velocities leaves a lot to be desired as far as credibility is concerned.  My main point here is don't depend on Norsok P-100 (whatever the Revision) to help you design a practical, safe, and dependable methanol storage system.  They mean well, but leave a lot to be desired regarding this standard.

Attached File  NORSOK Standard Rev2 and 3 Differences.docx   29.89KB   63 downloads



#11 mykid

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Posted 11 December 2014 - 01:49 AM

ART Montemayor,

 

Really glad to see your reply. Have read a lot of your responses in the forum before. Thanks .

 

I found some documentation, it seemed that they have installed flame arrestor previously. The flame arrestors were removed probably due to blockage.

 

Due to lack of data, although P&ID has shown the filling connection with dip pipe, we will have have to open the manway to verify its presence. The overflow connection will be blanked off.

 

Unfortunately, there is no mechanical calculation available for this tank . In this case, if we rely on the ASME VIII calculation ( 9 barg), we can safely considered this as pressure vessel, and provide a PSV instead of a PVSV. The PSV will be sized for fire case with set pressure of probably 5 barg. The PSV discharge can be routed to LP flare header nearby.

 

AS methanol vapour pressure is around 0.3 bara, we will install a PRV to keep minimum 0.1 barg in the methanol tank during normal operation and set the outbreathing valve as 0.2 barg.

 

There is one question that i would like to ask with regards to inbreathing rate of N2. If this is a pressure vessel, then API 2000 does not apply. Can we take the inbreathing = pump out rate instead of the equation given in API 2000? Currently based on API 2000 equation, the inbreathing rate is 10 times of the pump out rate.  

 

Given that there is no nitrogen generator in our system, we are trying to limit the nitrogen usage. How to work out the number of cylinders required for inbreathing?



#12 shan

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Posted 11 December 2014 - 08:13 AM

NORSOK P-100 Rev 2, November 2001

 

19.7 Interface requirement

....

Inert gas      Storage tank purging / blanketing.

 

**************************************************

No PSV or PVSV is needed for your methanol storage tank because it is a tank with unblocked open to atmosphere.  Continuous N2 purge is required to prevent methanol contacting with air to have oxidation.  Methanol vapor loss with N2 purge is manageable because methanol vapor pressure is 4 psia at 100 F, which is much less volatile than a lot of stabilized oil stored in atmospheric tank.



#13 Art Montemayor

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Posted 11 December 2014 - 12:36 PM

Mykid:

 

In order to give our Forum members the necessary basic data and information to comment intelligently and accurately on such an important topic, your detailed input and information is required.  Experienced engineers will be reluctant to comment on a topic without having factual and detailed information in hand.

 

If you lack original detailed information, then furnish your own constructed information - in the form of data sheets, flow diagrams, sketches, basic calculations, dimensions and description of the equipment in question, etc., etc..  For example, did you purchase this tank assembly as a used, second-hand item?  If it was originally fabricated for your project or under your guidance, then the specifications should be available.  But at least tell us.  For example, what kind of heads does the tank have - and their thickness?  If the tank is truly fabricated in Stainless Steel, how is it going to be protected from Chloride Stress Corrosion once it is in operation on the FPSO, exposed to ocean spray?

 

All related items to the tank and piping should be welded.  No screwed connections are allowed for MeOH service - this is not a preference from me, but the mandate of every experienced engineer who has worked with MeOH in this type of application.  Additionally, if dip pipes are indeed installed, do they have a vacuum break hole drilled in them?  Is this indicated on the P&ID - as it should be?  If it isn’t, then your assembly is an example of shoddy and reckless engineering and should be suspect of its entire design.  Here, I am not being critical of whoever designed and built the unit, but trying to give you some valuable advice on what should be a safe, operable, and controllable operation.

 

Please give us the WHOLE story - or at least all information that you have, have calculated, or can obtain.  Our members can’t go out on a limb speculating as to what is really out there.  Be sure to tell us if you can tolerate an MeOH liquid or vapor leak on board the FPSO while it is in service.  Tell us if your risk analysis, insurance company, the local legal authorities, stock holders, etc. all allow you to accept it and also allow open purging of methanol vapors on the vessel.  The answer should quickly narrow down any speculation as to what you should be doing to protect the personnel on board, the tank, its operation, the FPSO, and the environment - all in that order.  The Fire Case is not the only potential hazard to the tank.  Is it protected against an overfill?  What are the filling procedures?



#14 fallah

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Posted 11 December 2014 - 01:51 PM

Yes, the methanol can be stored in an atmospheric storage tank as Norsok Standard mentioned but the main point is that the tank has to be a floating roof type. Actually, if it's not intended the methanol to be stored in a pressure vessel, it will be stored in Internal Floating Roof Tanks with provision of the N2 blanketing facility for the space between floating and fixed roofs...



#15 mykid

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Posted 12 December 2014 - 02:07 AM

The methanol tank was designed by a local contractor during the FPSO conversion.  However there isn't many documentation with regards to the tank,  ie. no mechanical calculation, only the general arrangement of the tank.

 

After the conversion, the vessel was never in use for the last project.

 

For this new project, client has specified the requirement of methanol for hydrate inhibition during startup. A quick review on the existing methanol tank P&ID reveals the inadequacy for the design. I have attached for your information.

 

It appears that the original design intent is to have continuous nitrogen purge during startup. Once the operation is over, the nitrogen valves will be closed. Although not shown on the P&ID, it was understood that there was an open vent with flame arrestor previously installed on the vessel. It was probably removed on the last project due to blockage. Since the vessel is always open to atmosphere, thermal inbreathing/outbreathing is taken care of. There is also no such need for the PVSV.

 

There is a drip tray below the vessel to handle any spillage of methanol or overflow. However if the proposal is to connect the vent line to LP flare header, then overflow of methanol will be collected in the LP flare drum instead. 

Given the vicinity of the skid to the staircase and walkway, it will be safer to have the nitrogen blanket on the vessel instead of having it open to atm.

Attached Files


Edited by mykid, 12 December 2014 - 02:13 AM.


#16 mykid

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Posted 12 December 2014 - 02:21 AM

ASME VIII calculation based on 9mm SS316 shell thickness, gives 0.9 MPa internal pressure. Therefore the vessel will be treated as pressure vessel rather than atm tank.

Attached Files



#17 shan

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Posted 12 December 2014 - 07:48 AM

It is OK to vent the purging N2 stream into open ambient, because air contains 78% N2 anyway.  If you use LP fuel gas as the purging medium, you may consider to tie the purge stream outlet to LP flare header.

 

I agree to remove the flam arrestor from the purge outlet because N2 with trace methanol vapor is not flammable at all.

 

I don't think it is feasible to install a floating roof tank on a FPSO, which is typically designed for 9 degree tilt movement to horizontal plane in all the directions.



#18 MTumack

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Posted 12 December 2014 - 12:39 PM

I would be concerned using this as a pressure vessel.

 

For one, the Heads are not flanged or dished; you essentially have the entire internal pressure multiplied by the head area shearing at the seams of the heads. I will not do this stress analysis for you, but my intuition tells me it will likely fail. There is a reason these heads are typically dished.

 

Second, your ASME VIII calc is only for Shell Thickness, and is incorrect as it does not leave you with a Corrosion Allowance. If you intend to use this thing at a pressure, it will corrode internally and your thickness after five years might lose 60 thou worth of steel, suddenly you have a smaller wall thickness. Your calculated structural thickness must ignore any Material tolerances and corrosion allowance; You say you have 9mm of steel, but you need to subtract  probably 1.2 to 2.0 mm for Mill tolerances (fluctuations in the thickness of the material based upon errors in the plates manufacturing and rolling operations) and another 3.2 mm (for sour/severe service) for corrosion allowances due to Methanol increasing the risk of Stress Cracking in structural steel.

 

Even disregarding this, you have no tractability of the make of the Vessel, the materials used, no stamp... any safety inspector worth his salt wouldn't even let this thing get to commissioning as a pressure vessel. Personally, I would not put my career on the line gambling on the suitability of this vessel/package, and I definitely wouldn't make operations have to work around this thing being pressurized.

 

In addition, I would remove all threaded connections, and at thise point you are better off building a new package with a contractor designing this thing for the service you intend to put it into. Make no mistake, this is an atmospheric tank by design and should remain that way in operation.


Edited by MTumack, 12 December 2014 - 01:37 PM.


#19 Art Montemayor

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Posted 12 December 2014 - 05:43 PM

Mykid:

 

After reviewing the additional information you have submitted and doing some calculations, my comments on what you propose are as follows:

  • I cannot justify the use of this vessel as a pressure vessel under the conditions you propose.  Your confirmation that the vessel does indeed have flat heads (as I suspected) means that this vessel requires approximately 3” (76 mm) thick flat heads - which I seriously doubt it has - in order to withstand 0.9 MPag of pressure.
  • As I’ve stated previously, the 304 SS material makes it susceptible to chloride stress corrosion from seawater spray that would surely get on it.  This makes the vessel undesirable due to the stress imposed on it.  I would not recommend this vessel even if it was used at atmospheric pressure.
  • You are perfectly correct in your suspicions about this vessel in this application.  The manway and the other indicated fittings on it are nothing more than potential leak sites and are definitely undesirable from a safety viewpoint.  Although the SS makes for a desirable, clean storage condition prior to submitting the fluid to a very high pressure pump that demands ultra-clean fluid, the tradeoff that you inherit with the SS is that it can’t tolerate a salt ambient - which is exactly what your installation proposes.
  • I also would strongly caution you about siting any methanol tank under - or in the vicinity of any staircase, walkway, or personnel passage.  In the event of a methanol fire on board the ship, personnel could be totally unable to escape the area.  The methanol storage, as I’ve pointed out before, should always be remotely located where it does not lend itself to ignition points, personnel escape routes, and other hazardous situations.  I have always worked on offshore projects with the knowledge that "there is no parking lot" - i.e., there is nowhere to run to or hide on a platform or FPSO in the event of fire or explosion.

Based on all the work involved to make this tank safe, operable, and dependable, you would be better off using it for something else and replacing it with a new, specifically designed and fabricated carbon steel methanol tank.  If it were me and money was scarce, I would buy an LPG “bullet” storage tank and use it instead with a nitrogen pressurized blanket of approximately 50 to 100 psig.



#20 MTumack

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Posted 12 December 2014 - 06:18 PM

I would also guess, as someone who works for a fabricator, that the vessel has had little to no NDE done on it aside from a leak test, and is likely not even welded with full penetration welds.

 

Do not use this tank as a pressure vessel, commission and spend your money on a new unit that is designed for the service you intend.



#21 mykid

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Posted 15 December 2014 - 12:39 AM

Thank you all for the valuable feedback and the time to review and reply to this topic.

 

The original design of the tank is meant for Methanol storage (even though the design looks shaddy), and the tank dwg and P&ID were  approved by the certifying authority.

 

Our contract is based on supplying the FPSO as it is, i.e. the existing state of the vessel. However i am concern on the adequacy of  the methanol tank design for serving this purpose. To replace the methanol tank with a new one is certainly outside the current project budget and will have to be a variation order to be approved by client.

 

Therefore to recommend a total change out, i will need a very strong justification on why the existing tank is not suitable.

 

My point of views are as follows:

1. To keep the existing tank, we can provide nitrogen purge during normal operation by crack open the existing globe valve and vent to atm. This will mean that N2 squad probably need to topup more often. In this case, since the tank is open to atm, PVSV and flame arrestor is therefore not required.

 

Existing Methanol tank has no threaded connection. However we need to verify the presence of dip pipe with vacuum break hole for filling.

 

With regards to the suitability of SS316 in offshore environment, my understanding is that SS316 material is subjected to chloride stress cracking in offshore salt laden environment when the temperature is above 60 deg C. In this case the tank is operating at ambient condition, therefore it should be okay. The existing tank was exposed to the marine environment for the past few yrs, its actual condition are to be verified.

 

Relocation of the methanol tank is also out of the question as the FPSO has no other place to place this tank. Putting it beneath the platform is not acceptable, and on the process platform, it is already crowded with all the other process equipments and piping.

 

 

 

Based on all the responses received so far, it seems that this tank is designed as atm tank, and is not suitable to be used as pressure vessel.



#22 MTumack

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Posted 15 December 2014 - 12:48 PM

I would hesitate calling it a shody design, its just not designed for this service.

 

Case in point, a Honda Civic is an amazing piece of engineering. However, if you want to tow a trailer, a Honda Civic is just not acceptable. Same thing here, you have a Honda Civic (Your Methanol Tank) but you need a Dually type truck.

 

You likely would not save any money adapting this thing into a pressure vessel; would require cutting the heads off, purchasing new heads, welding them on, Cutting and creating nozzles for Blanket Gas and a PSV, doing the full radiography procedures, the QC, finding yourself a way to get either a U stamp and/or Canadian CRN / A Stamp, externally coating it to save it from the Salt Stress Cracking...

 

Thats likely $90,000 to 130,000 depending on field rates if you are doing this work on site. Then you have to track down and probably do even more QC to qualify that all the materials meet ASME, because even though the block says it is an AMSE VIII design, I guarantee it is just a drafting oversight by your contractor.

 

To get a quality unit designed for this service is likely about the same cost.

 

Just buy a new unit.



#23 kennysafety

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Posted 16 May 2016 - 02:58 AM

Good day all, kindly assist me with an answer to this question; is it necessary to inert a tank 50% filled in an open deck of a vessel offshore during operation of methanol injection ? Note the portable tank will be on board for a prolong period. Thanks 



#24 Art Montemayor

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Posted 16 May 2016 - 11:14 AM

kennysafety:

 

First of all, this is a valid and important question that should be addressed with serious safety consequences in mind.

Secondly, Please take this post and start a NEW thread dedicated specifically to this topic.  Your query is important; but it invades someone else's topic and makes for confusion and chaos with our expert members who try to answer either one of the topics.

 

I will delete this post when you post your new thread.



#25 kennysafety

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Posted 18 May 2016 - 09:23 AM

please bear with me for this. Thanks




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