Process Modeling and Techno-Economic Analysis of Thermo-Catalytic Dimethyl Ether Synthesis and Microwave-Based Aromatics Production Technologies from Shale Gas

Author

Chirag Mevawala, West Virginia UniversityFollow

Semester

Fall

Date of Graduation

2020

Document Type

Dissertation

Degree Type

PhD

College

Statler College of Engineering and Mineral Resources

Department

Chemical and Biomedical Engineering

Committee Chair

Debangsu Bhattacharyya

Committee Member

Jinali Hu

Committee Member

Stephen Zitney

Committee Member

Xingbo Liu

Committee Member

Jingxin Wang

Committee Member

Richard Turton

Abstract

Production of dimethyl ether (DME) and direct non-oxidative methane dehydroaromatization (DHA) to aromatics via conventional and microwave (MW)-assisted processes are investigated in this research. Plant-wide models of the shale gas to DME process with integrated CO₂ capture via direct and indirect synthesis routes have been developed. Optimal parameter estimation, and model validation are undertaken for various sections of the process including the pre-reforming reactor, auto-thermal reforming reactor, DME synthesis reactors, CO₂ capture units and separation sections. A novel DME separation process has been developed for efficient separation of DME, syngas, and CO₂. Plant-wide techno-economic optimization is performed in an equation- oriented environment for maximizing the net present value (NPV). Effects of key design parameters and investment parameters on the process economics have been evaluated.

For the conventional as well as MW-assisted direct non-oxidative methane dehydroaromatization (DHA) process, dynamic data reconciliation, parameter estimation, and multi-scale, multi-physics dynamic fixed-bed reactor model development are undertaken. Due to rapid coke formation, catalysts in the non-oxidative methane DHA reactors get deactivated. A model for the catalyst deactivation is proposed along with rate models for other DHA reactions. An algorithm is developed by coupling an iterative direct substitution approach with an optimization algorithm for optimal estimation of the initial state of the reactor and the kinetic parameters using the in-house experimental data. For the MW-assisted reactor, the amount of heat generated at specific catalyst sites has been modeled using Maxwell’s equation. For integrating the Maxwell’s equation within the process model, a reduced order model is developed. A 2-D multi-scale heterogeneous industrial scale MW rector model is developed by coupling the catalyst pellet level model with the reactor level model. In addition, plant wide models are developed, and techno-economic analysis of the conventional and MW-assisted processes are performed.

Recommended Citation

Mevawala, Chirag, "Process Modeling and Techno-Economic Analysis of Thermo-Catalytic Dimethyl Ether Synthesis and Microwave-Based Aromatics Production Technologies from Shale Gas" (2020). Graduate Theses, Dissertations, and Problem Reports. 7963.
https://researchrepository.wvu.edu/etd/7963

Embargo Reason

Publication Pending