Novel Design of an Integrated Pulp Mill Biorefinery for the ...

Table of Contents
List of Figures ................................................................................................................................. 5
List of Tables .................................................................................................................................. 6
1 Introduction .................................................................................................................................. 7
2 Background .................................................................................................................................. 9
2.1 Pulp Mill Background ........................................................................................................... 9
2.1.1 Harvesting and Chipping ............................................................................................... 9
2.1.2 Pulping ......................................................................................................................... 10
2.1.3 Chemical Recovery ...................................................................................................... 12
2.1.4 Extending the Delignification Process ......................................................................... 13
2.1.5 Bleaching ..................................................................................................................... 13
2.1.6 Causticizing and Lime Kiln ......................................................................................... 14
2.1.7 Air Separation Unit ...................................................................................................... 15
2.1.8 Pulp Drying .................................................................................................................. 15
2.2 Black Liquor Gasification to Syngas .................................................................................. 16
2.2.1 Low-Temperature Black Liquor Gasification .............................................................. 17
2.2.2 High-Temperature Black Liquor Gasification ............................................................. 18
2.2.3 Black Liquor Gasifier Recommendation ..................................................................... 20
2.2.3 Coal Gasification Technology ..................................................................................... 20
2.3 Background of DME Synthesis .......................................................................................... 21
2.3.1 Properties of DME ....................................................................................................... 21
2.3.2 Features of DME Synthesis Technologies ................................................................... 22
2.3.3. DME separation and purification ................................................................................ 28
2.3.4 DME Utilization ............................................................................................................... 29
2.4 Fischer-Tropsch synthesis ................................................................................................... 30
2.4.1. Fischer-Tropsch Reactors ........................................................................................... 31
2.4.2. Fischer-Tropsch Catalyst ............................................................................................ 32
2.4.3. Fischer-Tropsch Mechanism ....................................................................................... 34
2.4.4. Fischer-Tropsch Product Selection ............................................................................. 35
2.4.5. Fischer-Tropsch Product Upgrading ........................................................................... 37
2.5 Heat and Power Generation .......................................................................................... 38
3 Process Design ........................................................................................................................... 39
3.1 Pulp Mill ............................................................................................................................. 39
3.1.1 Reference Plant ............................................................................................................ 39
3.1.2 Group Design Modifications ........................................................................................ 42
3.2 Black Liquor and Coal Gasification to Syngas ................................................................... 44
3.2.1 Gasifier Scale and Fuel Yield ...................................................................................... 45
3.2.2 Gasifier Fuel Source .................................................................................................... 46
3.2.3 Gasifier Synthesis Gas Composition ........................................................................... 48
3.2.4 Slag Properties and Chemical Recovery ...................................................................... 49
3.3 Dimethyl Ether Synthesis ................................................................................................... 52
3.3.1 Syngas Clean-up .......................................................................................................... 52
3.3.2 DME synthesis ............................................................................................................. 53
3.3.3 Product separation and purification ............................................................................. 56
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