Analysis of wastes generated at the refinery revealed that catalyst fines were entrained in the slurry oil manufactured by Valero's fuidized catalytic cracker unit (FCCU). The solids would settle in the product tanks consuming tank space. Residue from the tanks had to be removed and disposed of annually.
The Slurry Deashing Project (SDAP) was designed to remove catalyst fines from Valero's fuidized catalyst cracker slurry oil. The SDAP sends residue back to the FCCU where the catalyst fines are recycled, reducing purchase of make-up catalyst. The main thrust of the project included preventing frequent cleaning of residue from the product tanks and disposal of the residues.
The average, annual generation of residue prior to SDAP was about 3,000 tons/yr. Since implementing the project the average residue generation has been about 400 tons/yr. Reducing the rate of residue deposition means that the tanks need to be cleaned out less frequently.
Details of Reductions
Additional Information :
The SDAP project significantly reduced the frequency of clean outs where tanks had to be taken out of service. It increased the storage capacity of the tanks, and it reduced purchases of fresh catalyst. The projected payback of the project is 2.5 years.