Potential Problem of Direct Fired Heater for Crude Oil

[magicking]

Hi everyone,

My client insists to use direct fired heater to raise the temperature of crude oil but we insist to use indirect fired heater.

First Question: Is it acceptable to use direct fired heater for crude oil?

Second Question: If it is acceptable, what measures are necessary to allow them to operate safely and reliably?

Third Question: What is the potential problem to use direct fired heater for crude oil?

Thanks.

 

[monaco8774]

Only an opinion that may help

I used to work for a vendor that supplied both indirect and direct fired heaters

We would turn down bids for direct firing versus combustible fluids because if you get a pinhole leak you end up with an unknown inventory of flamable liquids direct on your burner, these ignite and you will get a pool fire in the fired heater. this may I suppose not escalate to outside of the vertical fired heater if you have some way of detecting it and then isolating fuel source and putting it out.

These jobs were still bid by competitors and they would win the job

I can see no real way of mitigating versus the risk as fire in the vertical fired heater is normal, you can detect tube leaks in a closed system where the inventory loss leads to loss of level in the header tank but unless the leak is large enough to cause a drop in pressure it would be difficult to detect in an unclosed system such as crude production.

 

[JLSeagull]

Direct fired heaters are common for crude oil. That does not necessarily make direct firing a good choice. Still, consider the available options for the direct fired approach. These might include a stack temperature transmitter and HI HI alarm. Determine whether an oxygen analyzer with combustibles measurement might detect the combustion products. You would want snuffing steam and trip valves to isolate the tubes or bypass the heater. Also consider side firing burners, etc.

BTW I am a control systesm engineer not a heater designer; and have not done a direct fired heater in a while.