ABSTRACT

Lignocellulosic biomass (LB) provides an alternate source to fossil fuel for chemicals, materials, and energy. A biorenery utilizing LB as raw material integrates multiple conversion processes to produce a range of products including liquid biofuels, biochemicals, steam/heat, and electricity. The challenge is to produce lignocellulosic products in an environmentally friendly system at

23.1 Introduction .......................................................................................................................... 477 23.2 Lignocellulosic Biomass ....................................................................................................... 478

23.2.1 Chemical Composition ............................................................................................. 478 23.2.2 Lignocellulosic Biomass Size Reduction: Pretreatment ........................................... 479 23.2.3 Biomass Size Reduction, Post-Pretreatment ............................................................. 481

23.3 Lignocellulosic Biomass Pretreatment ................................................................................. 481 23.3.1 Biological Pretreatment ............................................................................................ 482 23.3.2 Chemical Pretreatment ............................................................................................. 482

23.3.2.1 Acid Hydrolysis .......................................................................................... 482 23.3.2.2 Alkaline Hydrolysis ................................................................................... 483 23.3.2.3 Ammonia Recycle Percolation ................................................................... 483

23.3.3 Physicochemical Pretreatment .................................................................................. 483 23.3.3.1 Steam Explosion ........................................................................................ 483 23.3.3.2 Ammonia Fiber Explosion .........................................................................484 23.3.3.3 Hot-Water Pretreatment .............................................................................484

23.4 Sequential Lignocellulose Fractionation Biorenery System ..............................................486 23.4.1 Hot-Water Extraction ................................................................................................487