1. AspenWorld 2000 SYNTHESIS OF PROPYLENE GLYCOL BY REACTIVE DISTILLATION PROCESS SIMULATION AS A TOOL FOR THE CONCEPTUAL DESIGN OF NEW PROCESSES PROCESS SIMULATION AS A TOOL FOR THE CONCEPTUAL DESIGN OF NEW PROCESSES S. Galán 1, R. De María 1 & F. Domingo 2 1 ETSII-Universidad Politécnica de Madrid 2 Repsol-YPF, I&D Downstream, Química, Energía y Gas

2. AspenWorld 2000 OUTLINE l Propylene glycol production l Reactive distillation l Use of simulation through the design process: l Conceptual design l Kinetic model development l Pilot plant l Results: l Steady state multiplicities l Influence of variables

3. AspenWorld 2000 Reactions

4. Glycol production at Repsol-YPF l 2 plants: l Puertollano (Spain): 20,000 t/a l Tarragona (Spain): 50,000 t/a (@ 2000) l 2/3 Tubular reactors + 7 distillation columns l Important issues: l High Water/PO ratio to maximize MPG selectivity l Running cost related to water excess l Changes in product demand l Process flexibility

5. AspenWorld 2000 Current process

6. AspenWorld 2000 Reactive distillation

7. AspenWorld 2000 Conventional process vs. Reactive distillation

8. AspenWorld 2000 Simulation for Conceptual Design l Preliminary design l Screening of process alternatives l Profitability analysis l Definition of a base flowsheet

9. AspenWorld 2000 Simulation for Kinetic Modeling l Experimental program l Data regression l Analysis of results

10. AspenWorld 2000 Simulation in the Pilot Plant

11. AspenWorld 2000 Design of the Pilot Plant

12. AspenWorld 2000 Temperature profiles

13. AspenWorld 2000 Steady State Multiplicities

14. AspenWorld 2000 Composition profiles

15. AspenWorld 2000 Reaction rate profiles

16. AspenWorld 2000 Feed and pressure influence

17. AspenWorld 2000 Pressure influence

18. AspenWorld 2000 Boil-up ratio influence

19. AspenWorld 2000 Software Tools l ASPEN PLUS l MATLAB for data analysis l PITCON & AUTO for detection of multiplicities by homotopy continuation methods l ABACUSS for dynamic simulation

20. AspenWorld 2000 Conclusions l A process for MPG by hydration of PO in a (reactive) distillation column is considered profitable. l The interaction between reaction and separation introduces a more complex behaviour leading to new challenges in design, operation and control. l Repsol-YPF has been applying succesfully simulation (Aspen Plus) as a key tool through the development process. At this time, in the pilot plant stage.

21. AspenWorld 2000 l Santos Galán (sgalan@diquima.upm.es) l Francisco Domingo (fdomingor@repsol.es) l http://www.diquima.upm.es/proyectos/glicoles/glicoles.html