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| Author(s): |
Rodolfo Balthazar Vadinal
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Química |
| Defense date: | 2011-01-07 |
| Examining board members: |
Maria Regina Wolf Maciel;
Antônio Carlos Luz Lisbôa;
Rosângela Barros Zanoni Lopes Moreno
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| Advisor: | Maria Regina Wolf Maciel |
| Abstract | |
In the last two years, Brazil has been stamping the headlines of major media world with announcements of new discoveries of oil reservoirs in the Pre-Salt layer. Huge amounts of investments are being directed to facilitate the exploration and production of oil in ultra-deep depths. Meanwhile, refineries in Brazil (and worldwide refineries) now process oils that getting heavier and with higher levels of contaminants. To meet the growing demands of industries and consumer markets, conversion processes, among which stands out the fluid catalytic cracking unit (FCC), are highlighted. The catalytic cracking converts heavy fractions into lighter fractions and larger industrial interest. The main unit of a refinery that supplies the raw materials necessary for the operation of the FCC is the vacuum distillation unit (VDU), used to recover heavy oil fractions, especially the light vacuum gasoil (LVGO) and heavy vacuum gasoil (HVGO). The vacuum tower is used for processing heavy and ultra-heavy oils, making use of sub-atmospheric pressures to avoid thermal decomposition of petroleum constituents. Despite the technological advancement and development of refineries, computational models that allow a more detailed analysis to better understand the operation of the vacuum tower are necessary. Therefore, the objective of this work is to present new computational schemes for representation of the vacuum tower, performing a procedure for sensitivity analysis of process variables and to identifying a new operational point that maximizes the production of vacuum gasoil (VGO). The methodology proposed in this project is the use of three atmospheric residue (ATR) of different characteristics and the implementation of the VDU in the process simulator Aspen Plus, version 22.0. To represent the vacuum tower, four vacuum distillation columns are used, each one represents, from top to bottom: withdrawal section of LVGO; withdrawal section of HVGO; washing zone; and stripping section. After the implementation of the vacuum tower and the creation of specifications for LVGO and HVGO products, a sensitivity analysis was performed to evaluate the effect of operating parameters on the recovery process of ATR. The parameters studied were: injection of stripping steam; flow and temperature of the LVGO pumparound circuit; flow and temperature of the HVGO pumparound circuit; flow of washing oil; flow of hot reflux; overflash percentage; percentage of entrainment and furnace temperature. For a particular ATR, it was possible to increase the VGO production by up to 14%. The development of computational models and simulation results are important for two reasons: firstly, because they are not easily found in the open literature and, secondly, for the possible use in operator training (AU) | |
| FAPESP's process: | 09/12604-2 - Development of models for crude distillation plants with vacuum units: since the robust approach to operator training |
| Grantee: | Rodolfo Balthazar Vadinal |
| Support Opportunities: | Scholarships in Brazil - Master |