Development and innovation of sustainable technologies are critical for the clean and efficient production of chemicals and biochemicals. Reactive distillation (RD), a successful example of Process Intensification (PI), offers environmental and economic advantages compared to conventional technologies and contributes to sustainable development by combining reaction and separation. This synergistic combination allows overcoming azeotropes while increasing reaction rates, overcoming chemical equilibrium, and improving selectivity. The main advantages of RD include reduced footprint due to integrated functions in a single device that results in energy savings (e.g., the heat of reaction is used to assist vaporising the liquid phase), increased safety due to reduced inventories and the ability to avoid runaway reactions. However, the applicability of RD - the fact of being useful in a particular application - is limited because the operating conditions for reaction and separation need to overlap. Advanced reactive distillation technologies (ARDT) integrate the benefits of RD and additional features of PI, allowing greater overlap between reaction and separation operating conditions, which are represented and evaluated in operating windows. Therefore, this PhD thesis focuses on expanding the applicability of reactive distillation into typically restricted chemical systems and operating conditions by enabling rapid and early-stage systematic assessment of the technical feasibility of ARDT using first principles and heuristics. The technologies studied in this research are reactive dividing-wall columns (R-DWC), catalytic cyclic distillation (CCD), reactive internally heat-integrated distillation (R-HIDiC), reactive high-gravity distillation (R-HiGee), and membrane-assisted reactive distillation (MA-RD). These technologies have demonstrated better performance than conventional configurations in simulation-based studies. However, their industrial application is still scarce. To date, the synthesis and design of chemical processes progressively rely on complex computational methods thanks to the increase in computing power and the development of more robust solvers. Most of these approaches cover a range of traditional and well-established unit operations, while intensified equipment is considered superficially, especially novel technologies such as advanced reactive distillation. Process synthesis, targeting intensified equipment, will help process designers develop novel process flowsheets applying non-conventional processing options, where these can improve process performance by reducing energy consumption, increasing throughput, and reducing waste with a safer operation. This research is the first to create and provide a systematic approach targeting ARDT to expand the applicability of reactive distillation. This PhD thesis aims to develop a systematic methodology to expand the applicability of reactive distillation by assessing the technical feasibility of advanced reactive distillation technologies during process synthesis, while minimising requirements for process data and computational effort. Published case studies covering experimental, modelling, simulation and optimisation investigations and a study within the thesis - conceptual design of a dual reactive-dividing wall column using rigorous models in Aspen Plus - are used to underpin the research approach, the development of the methodology and the testing and verification of the resulting flowsheets. The basis and scope of the methodology to be developed was established in a conceptual framework that considers key thermodynamic properties and kinetic parameters for a given chemical system and its liquid-phase reactions and by formulating high-level questions. Furthermore, the simultaneous reaction and separation result in complex mixtures containing components in varying amounts and of different natures (e.g., reactive, inert), which can affect operation by narrowing oper
- Operating window
- Synthesis methodology
- Process simulation
- Reactive distillation
- Process synthesis
- Process intensification
- Process design
Expanding the applicability of reactive distillation
Pazmino Mayorga, I. (Author). 1 Aug 2023
Student thesis: Phd