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Towards Sustainable Production of Chemicals and Fuels from the Fast Pyrolysis of Waste Polyolefin Plastics

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Towards Sustainable Production of Chemicals and Fuels from the Fast Pyrolysis of Waste Polyolefin Plastics Michigan Technological University Digital Commons @ Michigan Tech Dissertations, Master's Theses and Master's Reports 2019 TOWARDS SUSTAINABLE PRODUCTION OF CHEMICALS AND FUELS FROM THE FAST PYROLYSIS OF WASTE POLYOLEFIN PLASTICS Ulises Gracida Alvarez Michigan Technological University, [email protected] Copyright 2019 Ulises Gracida Alvarez Recommended Citation Gracida Alvarez, Ulises, "TOWARDS SUSTAINABLE PRODUCTION OF CHEMICALS AND FUELS FROM THE FAST PYROLYSIS OF WASTE POLYOLEFIN PLASTICS", Open Access Dissertation, Michigan Technological University, 2019. https://doi.org/10.37099/mtu.dc.etdr/797 Follow this and additional works at: https://digitalcommons.mtu.edu/etdr Part of the Catalysis and Reaction Engineering Commons, Computer-Aided Engineering and Design Commons, Other Chemical Engineering Commons, Polymer and Organic Materials Commons, and the Sustainability Commons TOWARDS SUSTAINABLE PRODUCTION OF CHEMICALS AND FUELS FROM THE FAST PYROLYSIS OF WASTE POLYOLEFIN PLASTICS By Ulises Raymundo Gracida Alvarez A DISSERTATION Submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY In Chemical Engineering MICHIGAN TECHNOLOGICAL UNIVERSITY 2019 © 2019 Ulises Raymundo Gracida Alvarez This dissertation has been approved in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY in Chemical Engineering. Department of Chemical Engineering Dissertation Co-Advisor: Dr. David R. Shonnard Dissertation Co-Advisor: Dr. Julio C. Sacramento Rivero Committee Member: Dr. Gerard T. Caneba Committee Member: Dr. Joshua M. Pearce Department Chair: Dr. Pradeep K. Agrawal Table of Contents List of figures ................................................................................................................... viii List of tables ...................................................................................................................... xii Preface............................................................................................................................. xvii Acknowledgements .......................................................................................................... xxi List of abbreviations ...................................................................................................... xxiii Abstract .......................................................................................................................... xxvi 1 Introduction .................................................................................................................1 1.1 Plastic waste generation and its environmental and economic repercussions ..1 1.2 Alternatives for plastic waste management ......................................................3 1.3 Circular economy of plastics ............................................................................4 1.4 Current state of the thermochemical conversion of polyolefins .......................6 1.5 Sustainable process design in the context of circular economy .....................10 1.6 Research objectives ........................................................................................12 1.7 References ......................................................................................................14 2 Resource and Greenhouse Gas Assessments of the Thermochemical Conversion of Municipal Solid Waste in Mexico .....................................................................................21 2.1 Introduction ....................................................................................................22 2.2 Methods ..........................................................................................................26 2.2.1 Resource assessment .........................................................................26 2.2.2 Estimation of fuel yields ...................................................................28 2.2.3 Carbon footprint analysis ..................................................................29 2.3 Results and discussion ....................................................................................34 2.3.1 MSW resource assessment in Mexico ..............................................34 2.3.2 Pyrolysis yields for the selected feedstock .......................................36 2.3.3 Environmental assessment ................................................................38 2.4 Conclusion ......................................................................................................41 2.5 Acknowledgements ........................................................................................42 2.6 References ......................................................................................................43 iii 3 Effect of Temperature and Vapor Residence Time on the Micropyrolysis Products of Waste High Density Polyethylene .................................................................................47 3.1 Introduction ....................................................................................................48 3.2 Experimental section ......................................................................................54 3.2.1 Sample preparation ...........................................................................54 3.2.2 Micropyrolysis Reactor and Conditions ...........................................54 3.2.3 Analytical Methods ...........................................................................57 3.3 Results and discussion ....................................................................................59 3.3.1 Temperature Performance of the TSMR ...........................................59 3.3.2 GC/MS Chromatogram of the TSMR ...............................................60 3.3.3 Effect of temperature and VRT in the distribution of different carbon number fractions .............................................................................................62 3.3.4 Relative change in yield of different C number fractions .................68 3.3.5 Effect of temperature and VRT in the distribution of different chemical classes..............................................................................................70 3.3.6 Pyrolysis of waste HDPE at 700 °C and zero VRT ..........................72 3.3.7 Comparison of the TSMR performance with different reactor configurations .................................................................................................74 3.3.8 General mechanism of HDPE degradation at two-stages .................79 3.4 Conclusions ....................................................................................................80 3.5 Acknowledgements ........................................................................................81 3.6 References ......................................................................................................82 4 Systems Analysis of High-value Chemicals and Fuels from a Waste High-Density Polyethylene Refinery. Part 1: Conceptual Design and Techno-economic Assessment ...86 4.1 Introduction ....................................................................................................87 4.2 Materials and methods ....................................................................................90 4.2.1 Conceptual design of the refinery .....................................................90 4.2.1.1 Pyrolysis section (A-100) ...............................................93 4.2.1.2 Monomer separation section (A-200) .............................93 4.2.1.3 Aromatics extraction section (A-300) .............................94 4.2.1.4 Hydrotreatment section (A-400) .....................................96 4.2.1.5 Refrigeration cycles and heat integration .......................98 4.2.2 Energetic evaluation..........................................................................99 4.2.3 Techno-economic analysis ..............................................................100 4.2.3.1 Cost estimations ............................................................100 4.2.3.2 Discounted cash flow analysis (DCFA) ........................101 4.2.3.3 Sensitivity analysis........................................................103 4.2.3.4 Scenario analysis ...........................................................103 4.3 Results and discussion ..................................................................................104 4.3.1 Material and energy balances..........................................................104 iv 4.3.2 Primary energy requirements ..........................................................107 4.3.3 Product yields and energy efficiency ..............................................109 4.3.4 Capital costs ....................................................................................111 4.3.5 Discounted cash flow analysis ........................................................115 4.3.6 Sensitivity analysis..........................................................................119 4.3.7 Scenario Analysis............................................................................121 4.4 Conclusions ..................................................................................................124 4.5 Acknowledgements ......................................................................................125 4.6 References ....................................................................................................126 5 Systems Analysis of High-value Chemicals and Fuels
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