The chemistry related to converting lig-nocellulosic feedstocks into biofuels is well understood. However, the engineering pro-cesses required to affect the conversions are still being developed and are not expected to be widely commercialized before 2020. Generally speaking, lignocellulosic biofuels are made using biochemical or thermo-chemical conversion processes. Biochem-ical conversion is used to make cellulosic ethanol. This process is much more diffi-cult than the first-generation processes of converting starches and sugars. With lig-nocellulosic feedstocks, the plant cell walls are composed of complex polymers, which must undergo a first stage of acid hydro-lysis, then separation of liquids and solids, and a second stage of acid hydrolysis before the fermentation and distillation of sugars into ethanol. This complexity will add sig-nificant cost over first generation ethanol production. Thermochemical processes include py-rolysis and gasification. The main product of pyrolysis is bio-oil, which can be re-fined into transportation fuels and other chemicals. Unfortunately, bio-oil is acidic, has high water content, and is unstable. Engineering processes to cope with these challenges and to purify bio-oil are still be-ing developed. The main product of gasifi-cation is syngas, which can be refined into ammonia, methanol, synthetic natural gas, other chemical outputs, and even jet fuel. The processes to produce biofuels through gasification are also still under develop-ment. Thus, it is unlikely that second-gen-eration biofuels will be widely deployed before 2030. Wood pellets would be a highly desir-able feedstock for lignocellulosic biofuels. Compared to other feedstock options, wood pellets are homogenous; they are low in ash, moisture, chlorine and nitrogen. They are widely available. They are easily transportable and a dependable wood pel-let supply chain exists. If biofuel developers choose to use forestry residues rather than wood pellets as feedstock, then significant cost will be added to carry out much of the necessary pre-treatment that has already been accomplished though the wood pellet production process. However, lignocellulosic biofuels will ultimately have to compete for market share with first-generation biofuels, and in-deed fossil fuels. While lignocellulosic bio-fuels will have superior GHG and sustain-ability credentials, they will still need to be reasonably cost competitive. Yet they will be more expensive to produce. This means that there will be enormous pressure to minimize feedstock costs, so wood pellets might prove to be too expensive. On the other hand, it is not likely that biofuels will be able to compete with wood pellets for access to forestry residues. Presently, unlike the lignocellulosic bio-fuel industry, which does not yet exist, the wood pellet industry is profitable. About 30 million tonnes of wood pellets are con-sumed annually for heat and power around the world. Annual consumption is continu-ing to grow at a rate of about 15 per cent annual production. It seems unlikely that we will see lignocellulosic biofuels as com-petition for wood pellets in the foreseeable future. • A provider of Bulk Materials Handling Solutions Receiving | Screening | Sizing | Conveying | Stacking | Reclaiming | Ship Loading www.Bruks.com | [email protected] CBM_Bruks_changes_MayJune17_MLD.indd 1 Canadian BIOMASS 2017-05-25 3:42 PM 11
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