Category: Pretreatment

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Techno-Economic Analysis of Forest Residue Conversion to Sugar Using Three-Stage Milling as Pretreatment

This study quantifies the cost of cellulosic sugar production using a fully-mechanical pretreatment process and fuel pellets as a co-product. The pretreatment reduces softwood forest harvest residuals to micron-sized amorphous particles. Energy consumption is minimized using a three-stage milling process. A techno-economic analysis was completed for a milling facility with saccharification and wood pellet manufacture. For the base case, concentrated sugar syrup can be produced for $0.496/kg of sugar. Sensitivity analyses were used to determine cost controlling variables, optimize the sugar cost and found that siting for this technology needs to strongly consider electricity cost and to a lesser extent local feedstock availability. If the sugar produced in this process is used to generate biofuel and is qualified for RIN credits through a life-cycle analysis, the effective cost could be reduced by $0.04–$0.06/kg of sugar. An additional $0.067/kg savings is possible if the biofuel facility is located adjacent or on-site; the finished sugar syrup would not have to be concentrated for transportation. An optimized scenario, including the RIN credit, dilute sugar syrup, and favorable energy costs and consumption, could reduce the cost to $0.34/kg sugar compared to $0.496/kg for the base case.

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Pretreatment of Woody Biomass for Biofuel Production: Energy Efficiency, Technologies, and Recalcitrance

This mini review discusses several key technical issues associated with cellulosic ethanol production from woody biomass: energy consumption for woody biomass pretreatment, pretreatment energy efficiency, woody biomass pretreatment technologies, and quantification of woody biomass recalcitrance.
Follow this link to learn more: http://www.treesearch.fs.fed.us/pubs/36441

SPORL Patent: Ethanol Produced as By-product, or from Waste, or from Cellulosic Material Substrate, or Substrate that Contains Cellulosic Material

The present invention relates to a method using sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL). More specifically, it relates to a sulfite-based chemical process for pretreating biomass in solutions to reduce access barriers of enzymes to the lignocellulose, resulting in efficient conversion through enzymatic saccharification.
Follow this link to learn more: http://www.faqs.org/patents/app/20090298149#b

Enzymatic hydrolysis of cellulosic biomass

Enzymatic hydrolysis that converts lignocellulosic biomass to fermentable sugars may be the most complex step in this process due to substrate-related and enzyme-related effects and their interactions. This review looks at which organisms produce enzymes, as well as the chemistry and physics of these enzymatic processes.
Follow this link to learn more: http://www.cert.ucr.edu/research/ses/Enzymatic%20hydrolysis%20of%20cellulosic%20biomass.pdf

Effects of hardwood structural and chemical characteristics on enzymatic hydrolysis for biofuel production

This study investigated the influence of various hardwood characteristics on enzymatic hydrolysis. Important hardwood species, including three Eucalyptus species, were comprehensively characterized using quantitative 13C NMR, image analysis and fiber quality analysis. Hydrolysis efficiency from all the hardwoods was correlated to the wood chemical composition and lignin characteristics.
Follow this link to learn more: http://www.sciencedirect.com/science/article/pii/S0960852412001095