2 replies to this topic

[IntotheDream]

Nice to meet legendary engineers in Cheresources. I am now working in refinery of South Korea. It is second year as a operation engineer so there are a lot of query to deal with about refinery.

 

As one of them, I got a question about a criteria of Piping steaming-out

 

As far as I know, There are two main purpose of piping steaming-out.

1. O2 freeing 2. Hydrocarbon stripping

 

In the case of O2 freeing criteria, it is commonly known as a rule of thumbs that O2 freeing is applied about 5-6 times of system volume. Do you know the criteria for hydro-carbon stripping? Any reference or rule of thumbs would be appreciated. Thank you in advance for your answers. 

[ankur2061]

Hi,

 

The thumb rule for hydrocarbon purging using steam or any other inert medium is to provide a quantity which is 8 times the system volume (piping or equipment) to ensure that the system is completely purged of any flammable hydrocarbons which can cause internal deflagration and in a worst case scenario an internal detonation.

 

Reference for the 8 times are difficult to find. Since purging with 8 times the system volume has worked successfully, and practically trying to determine the purge volume doesn't much make sense, since during start-ups and commissioning enough utilities are available for such operation, I guess it is not a worth while activity. There is a major exception although, of long distance pipelines, where purging requires detailed calculations for purge gas, since this involves large system volumes.

 

Regards,

Ankur.

[breizh]

Hi ,

Consider the use of an explosimeter well calibrated to monitor the quality of the steam out ,

 

my view .

Breizh