Effects of Variables on a Soaker-Stripper Reactor for Thermal Cracking of Deasphalted Oil

Vast resources of heavy oils like Canadian bitumen are available and processed through many different schemes to bring a synthetic crude oil to markets. One effective scheme in use employs Solvent Deasphalting (SDA), a versatile upgrading process that uses light alkanes to precipitate the asphaltic phase from the feedstock, producing Deasphalted Oil (DAO), a stream with reduced asphaltenes and metal content. In that industrial scheme DAO is thermally cracked to generate distillates with conversion of the 553 °C+ fraction over 50%. One important current challenge is to increase that conversion level by optimization of the reactor and the flow regime inside it. In this work, a pilot plant was designed, procured and built to investigate the thermal cracking of DAO with steam in a counter-current flow pattern reactor. The effect of a Raschig rings packed bed and variables such as reaction temperature and space velocity were studied. Among different techniques, Simulated Distillation (SD) was used for product characterization. The product characterization and reactor performance showed a limited effect of the Raschig rings and enhanced heat distribution due to the steam counter-current flow, which allows better performance at a lower temperature. A parametric study along with the corresponding product distributions for each experiment made possible the use of a kinetic model to describe the reaction network taking place. The model includes 5 lumps: residue (R), vacuum gas oil (VGO), distillates (D), naphtha (N) and gases (G). Thermal cracking of the residue followed first order kinetics with activation energies ranging from 172 to 250 kJ/kmol. Gases were found to be produced almost exclusively from residue, and naphtha was found to be a secondary product of the reaction scheme.

Name thesis:degree_name

Master of Science (MSc)

Discipline thesis:degree_discipline

Chemical and Petroleum Engineering

Grantor dc:publisher.institution

Graduate Studies

Year dc:date.issued

2014

Author dc:creator

• Gutierrez Aldana, Nestor David

Advisor dc:contributor.advisor

• Pereira-Almao, Pedro

• Engineering--Chemical

Statement dc:rights

• University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.

Language dc:language.iso

eng

DOI

http://dx.doi.org/10.11575/PRISM/25838

OAI identifier oai:identifier

oai:ucalgary.scholaris.ca:11023/1932