Q & A > Question Details
I am currently exploring the possibility of selling Slurry as Carbon Black Feedstock. Although most of the expected qualities of slurry are able to meet the specs required of the Carbon Black Feedstock, the slurry is still high in CCR (~20 wt% in Max LPG mode) versus the required spec of < 10 wt%. For an RFCC, is there any operational adjustment that can be done to meet the CCR specs?
10/04/2012 A: Victor Scalco, General Atomics Electromagnetic Systems (GA-EMS), Vic.Scalco@ga.com
In many installations of RFCC. A catalyst separator designed for the CCR and specs required for High Quality Carbon Black products can be used without fouling. The Gulftronic Electrostatic Separator is used exlusively with RFCC with removal of particles to <5ppm. Information at www.ga-esi.com
06/03/2012 A: RAJKUMAR YADAV CHEVVA, IOCL, yadavr@iocl.co.in
As far as slurry as CBFS is concerned, normally spec not includes CCR.Still to lower down the CCR of slurry catalyst flow across riser may be increased for more effective catalytic cracking of course if RCSV DPC permits. Alternatively BCA (bottom cracking additive) may be used as on option.If you do have slurry injection nozzle in your riser increase more recycle flow.Finally for check case just reduce your bottom temp by 2-3 degC ,which could solve the problem.
06/03/2012 A: Alan Goelzer, Jacobs Consultancy, alan.goelzer@jacobs.com
Micro Carbon Residue test response cited for the FCC Slurry Oil seems to be on the high end. Much of the MCR test response should be coming from condensation of tetra-aromatics and tri-aromatics and heavier di-aromatics [all with short alkyl/alkene branches]. This is different pathway to MCR test responses than found for vacuum gas oils & vacuum residues and heavy coker gas oils.
It is possible that there are some deficiencies in the regen catalyst supply ducting or final bend or lift zone or feed injectors or mix zone or Mix Zone Outlet Temperature or Riser Outlet Temperature. Such deficiencies may not be fully cracking and converting the resid cat feed. Possibly the resid cat feed is "too heavy" for the RFCC converter.
In any case, most of the heavy cycle oil should have been admixed with the slurry oil so that sales product reflects the full 350C/360C to 550C range.
Also, the slurry oil needs to be filtered in advanced filtration systems [to well below 50 wppm residual catalyst fines].
05/03/2012 A: Wim Bond, Licence to consult bv, wim.bond@zeggis.com
Best way to remove unwanted particles from the slurry stream is to add a full flow or partial flow self cleaning filters in the FCC slurry loop. However, you better prepare for the best choice of self cleaning filter (100% efficiency in the cleaning step, minimum backflush liquid). To help you find the best option (free of charge), please contact me at wim.bond@zeggis.com.