7 replies to this topic

[Sandy2000]

Dear Engineers

I have a problem in Flare system, n my project (a propylene plant) there is a limitation in high elevated equipment such as Flare stack (it is included the flame length)which could not be higher that 45meter.

as I estimated the flare height doesn’t meet the limitation so there is solution to use the ground flare but I don’t have any experience and idea to use this kind of flare.

Please tell me it is practical to use the mentioned flare and what is its pros and cons.

thank so much

[ankur2061]

Sandy,

Mentioned below are some points related to ground flares which I could put together in company standard I prepared for a middle-east O&G company:

Ground Flares

A ground flare is a fully shielded device that produces essentially no ground level radiation.

1. Following is the justification for providing ground flares :

a. To eliminate or reduce radiant heat to nearby equipment or work areas.
b. To reduce noise in the immediate vicinity.
c. To make the flare flame less obvious for community relations
d. To potentially achieve improved emissions.

2. Ground flares use multiple burner tips arranged on staged burners, ensuring smokeless burning under all flow conditions.

3. Ground flares generally have higher total costs compared to an elevated flare for the same load.

4.Ground flares have lower operation costs and better turndown (generally 0 to 100%).

Hope this helps.

Regards,
Ankur.

[afi]

Dear Ankur;

Thanks so much for your useful answer, but I have another problem too that in case of using the Multipoint ground flare how much sterilization area is needed(is there a relation between flare load and required area ?)
and what is the limitations in using ground(enclosed) flare,

Best Regards

[ankur2061]

Afi,

I think there is some misunderstanding in your comparison of a ground flare with an elevated flare. A ground flare is also an enclosed flare which means that there is no visible radiation from a ground flare which also means that there is no sterilization radius.

My earlier post has also mentioned that ground flares have a higher first cost compared to an elevated flare.

Hope this helps.

Regards,
Ankur.

[afi]

Dear Ankur;

I know that the enclosed ground flare is a type of ground flares and has no sterilization area but my question is about another type of ground flare which named Multipoint(open)ground flare (as in attached file), I want to know the calculation method of this kind of flare.

thanks

Attached Files

•  Document2.pdf   81.93KB   130 downloads
•  tp_safe 8.pdf   380.85KB   102 downloads

[ankur2061]

Afi,

In your attachment there is an option to provide radiation fence for the open ground flare which prevents any visible radiation.

The open flare radiation fence is made of steel with refractory lining to withstand the high temperatures.

Regards,
Ankur.

Edited by ankur2061, 25 August 2010 - 11:16 AM.

[afi]

Thanks for your reply,
So there is no need to take sterilization radius and another question that how I can determine the number of burners, how is related to the rate of burning?

thanks

[ankur2061]

Afi,

Number of burners for a ground flare requires specialist knowlwedge of flares. A lot of information related to flares is still empirical in nature and not in the public domain and only few vendors including:

John Zink

Flare Industries

Callidus Technologies

Hamworthy Combustion

can design ground flares. Anybody who needs to install a ground flare would contact any such reputed vendor to provide the exact configuration of the ground flare including the number of burners. Based on the basic engineeeing data for the flare provided to the vendor, the flare vendor would provide the design. I would not consider it wise for you to try and determine the number of burners based on what I have said above.

Hope this helps.

Regards,
Ankur.

Edited by ankur2061, 28 August 2010 - 08:24 AM.