3 replies to this topic

[Eric Nguyen]

Dear Forum!

Recently, Olefine content is suddendly increasing..What causes suddendly high olefine in RFCC Gasoline

Rgs

[PingPong]

Assuming the new analyses are correct (nothing changed in the lab with regard to used method, or used apparatus) there must be changes in the operating parameters.

Compare all available DCS data before and after change in olefin content.

Changes could be:

- change in feedstock (with lower hydrogen content, or higher Concarbon, or more metals, or more N, or more S, or more salt, or ..... )

- change in fresh catalyst type (maybe switch to different catalyst vendor or type)

- change in fresh catalyst addition rate

- change in spent catalyst metals content

- change in regenerator temperature

- change in reactor temperature

- change in cat/oil ratio

- change in lift gas flowrate

- et cetera (use your own imagination)

 

Check also whether the overall yield of gas, C3's, C4's, gasoline, LCO, slurry oil changed together with the change in gasoline olefin content.

And whether the olefin content of the LPG components also changed.

And whether the cetane index of the LCO also changed.

Edited by PingPong, 30 October 2014 - 05:57 AM.

[P.K.Rao]

Besides what Pingpong advised, please check the bromine number of the gasoline. This should also increase. If the olefins are done by PONA analyzer, this would be a supporting test. Hope you have earlier bromine number data. Compare the RON values also (earlier and present). It should also increase.

[Eric Nguyen]

Thank you