2 replies to this topic

[wenchop]

API 521 states: "The impact of multiple flares in proximity operating simultaneously needs to be considered when evaluating thermal radiation."

What we have is a case of several flare stacks/risers in parallel in close proximity sharing the same structure, so they are almost in the same location. The question is whether radiation can be calculated individually, then added to get a total radiation.

[flarenuf]

Hi magnoz,

as a rough idea of the total then yes simply adding the 2 or 3 will give you a figure.

However i assume that you have LP and HP tips on the same stack ?  These will bend in the wind  giving you different  flame paths and radiation levels at any point , if you have several points of interest in regard to incident radiation  on the plant then you will see differring contributions from each flame according to distances from flame centre path.
 

Software programs like FlareSim can handle radiation and temperature calculations for flaring from multiple tips on multiple stacks.
How deep you go with these sort of calculations depends on your objective eg: rough estimate, detailed design , rating.

Remember you are working in the safety aspect of process engineering here so make sure you do it right !

 

flarenuf

[wenchop]

Thanks for the reply.

 

No they are all HP, but one is spare.  The flare tips can be lowered to ground level for maintenance.  Flare systems with multiple risers allow service to be performed on all risers and flare burners except the flares in service.  So production can continue when performing maintenance on the flares. 

 

regards,