9 replies to this topic

[Vegeta]

Hi all,

 

I am a new chemical engineering graduate and in my job  I was assigned for an assignment in a project to install flow meters in main flare header, pilot and purge lines going to a burn pit. Can you advice on what information I will need and what type of flow meter shall be installed?

 

Thank you for your time....

 

Regards,

[Bobby Strain]

Search for suppliers of such equipment. John Zink Company for example.

 

Bobby

[fallah]

Vegeta,

 

The most important info you should know to specify the flowmeter in flare system are average passing flare/purge gas properties and estimated min/max mass flowrate. The flowmeter type normally applied in flare system is ultrasonic one by using which there would be no obstruction or blockage in the line included such flowmeter...

[Vegeta]

Thanks Guys,

 

Fallah, 

 

Is ultrasonic flow meter usually employed in purge and pilot lines or it is for the main header?

 

 

Again thanks,  

[farid.k]

Vegeta

 

Basically,

 

The type of flow instruments normally will be selected examining conditions such as :

 

1 -Required range for measurement

2 -Process and fluid properties of the stream (either liquid, gas or steam. For properties, do highlight on the viscosity of the fluid since some instrument not suitable for high viscous liquid)

3 -Purpose of measurement and required accuracy (i.e., for high accuracy or for billing purpose, coriolis will be used, but for your case, i do agreed with fallah to use ultrasonic. ultrasonic will not alter the flow inside the pipe, and they will outside of the pipe . Just that the price is moderately expensive)

 

It is also good to consult direct to the vendor as per Bobby Strain say since they can suggest directly to you.

 

regards

[Neelakantan]

@Vegeta

 

As usual (if you ever happen to read my posts!) my answer is more of questions!

 

1) exactly what you mean by Installing (in engineering context, it simply means physically installing?)

2) is it a trainee assignment or a real live project?

3) if live project, are not P&IDs made? then what are the notes and comments of the process engineering team who made the p&Ids?

4) or do your seniors want you to study the possibility of "installing" flow meters on an existing (brown field) plant to monitor the amount of gas and fuel flared/spent?

5) whenever a query is posted, a sketch and precise engineering  data will be useful to answer more meaningfully and to the point;

 

best wishes on your assignment

 

neelakantan

[Vegeta]

Neelakantan
1) We will provide the design to the client and later they will install the flow meters in accordance to our design.
2) Real Project.
3) as you said in 4.
I have just got some few information from the client (composition of flared fluid and average flared fluid flow).

Looking forward to your comments.
Thank you for your cooperation.

Vegeta

[Neelakantan]

without additional project information (such as line size, pressures, material, flow rate-min-norm-max, etc) it is difficult to recommend meaningfully

 

1) as your answer implies that you are in an engineering/construction company and the end customer is an operating unit, my first suggestion is to know what the end-customer really wants? secondly know their budget! and thirdly look if they want a permanent solution or temporary measurement for some study/audit

2) normally i dont go for measurement on purge or pilot gas flows; typically an RO is what i will go for which will have a "fixed" flow rate;

( the forum members and i would be very happy to see more of the data the pilot and purge line. PRVs, line sizes, etc with a sketch)

3) for the main flare, i could suggest ultrasonic (check at www.fluenta.com) as i have used one which gave good results..

 

 

regards

neelakantan

[Vegeta]

Neelakantan,

I will upload more information as I receive it. Excuse me if my question seems to be stupid but isn't it unsafe to install restriction type flow meters in such systems and it will be very likely to get chocked flow?

Regards,
Vegeta

[Neelakantan]

@vegeta

 

purge and pilot requirements are almost stable and fixed and so we use RO (you are right about choked flow)

 

regards

neelakantan