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Light olefins including ethylene and propylene are important chemical materials, and a diversity of production technologies have been applied in industrial processes. An index called Olefins Production Security Index (OPSI) is proposed for quantifying the performance of techno-economics and security for different olefins production routes. The results show that Coal via Methanol to Olefins (CMTO) and Coal via Methanol to Propylene (CMTP) routes have the higher security rank in terms of raw materials supply and reasonably good economic performance compared with the Nature Gas via Fischer–Tropsch Synthesis to Olefins (NFTO) and Deep Catalytic Cracking (DCC) routes. Carbon Dioxide via Methanol to Olefins (CDMTO) and Carbon Dioxide via Methanol to Propylene (CDMTP) routes have lower carbon dioxide emissions but higher direct production costs. Basically, CMTO, CMTP, and Nature Gas via Methanol to Olefins (NMTO) routes have the top OPSI grades, which means they are more competitive than other routes in terms of security. We also identify the shortcomings of each olefins production route with regard to the security through sensitivity analysis. It is expected the proposed framework plays a role in searching the most suitable production route for light olefins from the viewpoint of security. [Display omitted] • Light olefins production routes are evaluated against techno-economics and security. • Olefins Production Security Index (OPSI) is proposed. • OPSI considers effects of raw materials, energy, technology, economy, and CO 2. • OPSI can be genetically extended to other industrial productions chain. [ABSTRACT FROM AUTHOR]

Themethanol to olefins (MTO) process has been successfully commercializedin China and will potentially become an important route for lightolefins production. In this work, a modeling approach is presentedfor MTO fluidized bed reactor design and operation optimization. Thetwo-fluid model (TFM) where the solid phase shear viscosity and solidphase pressure are derived from kinetic theory of granular flow hasbeen used to model the solid–gas two-phase flows. The interphasedrag force is calculated by either the traditional Gidaspow modelor a recently developed EMMS-bubble model. The simulation study hasbeen performed for a fluidized bed reactor in a 16 kt/a DMTO unit.It has been shown that the Gidaspow model cannot predict a stabledense bed, while the EMMS-bubbling model could simulate the solidfraction distribution in the reactor reasonable well. A reaction modelbased on the simple MTO reaction kinetics has been implemented totest the effectiveness of the model approach. The simulation resultsshow that the methanol is converted rapidly just above the gas inlet.The selectivity of ethylene and propylene however are underpredicted,while the selectivity of CO2and other products are overestimated.It is suggested that a further extension of the EMMS model to a turbulentfluidized bed is important in order to get more quantitative results.Also the MTO reaction kinetics for a commercial DMTO catalyst, inwhich the coke formation kinetics should be included, is highly desired. [ABSTRACT FROM AUTHOR]