A Process Study On Fast Pyrolysis Of Biomass And Upgrading Of Bio-Oil

China is an agricultural country with abundant biomass resources, production of transportation fuels from biomass via fast pyrolysis is an important development direction and get more and more attention with good prospects. Although a lot of study have done, most are only partially studied and no discussion of the overall process. The puepose of this study is to develop technical models for assessment of the conversion of biomass to valuable fuel products via fast pyrolysis and bio-oil upgrading in ASPEN PLUS. To provide theoretical basis and scale-up support for its commercialization, this study nalysis material and energy balance for the entire process and optimize some of these operating parameters.An ASPEN model of fast pyrolysis was developed to simulate the operation of the bio-oil production plant, includes the pretreatment of the biomass, the pyrolysis reactor, and a combustion reactor. Simulating the each part of the process with the capacity of 2000 t/d corn stover, the results show that energy consumption for the whole process is 468.73×109 J/h and the generated energy is 531.6×109 J/h,which means that energy generated was greater than the energy consumption; the energy consumption of product 1 kg bio-oil is equivalent to 0.75883 kg standard coal, while the energy generation was 0.8606 kg standard coal; the optimal value of the amount of burning char is 86% of the total.In this paper, we select hydrotreating and hydrocracking of pyrolysis oil, separation of upgraded oil to gasoline and diesel fuel blendstocks, hydrogen generation to simulate the refining process of bio-oil. A mixture of model compounds is used to represent bio-oil that includes water, crotonic acid, hydroquinone, furfural, hydroxy acetone, cellobiose, levoglucosan dibenzofuran and dimethoxy stilbene. After catalytic hydrogenation, the results of yield distribution show that hydrogenated oil 41.39%, water 41.39%, small molecule gas 5.88%. The results contrast with the literature is basically the same. After further hydrogenation of pyrolysis oil, obtain gasoline components 8540 kg/h and diesel components 10907 kg/h, the yield is 41.68% and 53.23%, respectively. The energy consumption of product 1 kg gasoline and diesel from preliminary bio-oil is equivalent to 0.4319 kg standard coal.Finally, by analyzing the natural gas reforming process, we find that the optimal conditions for reforming reactor is temperature 720℃, pressure 20 bar, and the ratio of water and carbon 3. The energy consumption of product 1kg hydrogen from Natural gas is equivalent to 5.59 kg standard coal.In addition, in order to improve the utilization rate of biomass and the economical efficiency of the whole process, heat and power model is established. In the model, using the waste water and waste gas to generate steam and electricity, it can be obtained 48239.73 KW. In this process, three waters emissions are reduced. Besides, it is good for environmental protection, and the process economy could be improved.Comprehensive above simulation models, the models conduct a rigid material balance and energy utilization calculation about this process. As the capacity of 2000 tons per day of biomass fast pyrolysis plant, the result is that gasoline yield of 102 kg per ton biomass and diesel yield of 131 kg per ton biomass; units of energy biomass and natural gas utilization efficiency is 46.47%.