Study On The Production Of Bio-jet Fuel Composition From Vegetable Oils

With the fossil energy increasingly dried up,developing renewable resources that can substitute for fossil energy is already in the extremely urgency.And biomass is the only renewable energy can be transformed into liquid fuels,so the efficient use of biofuels can not only promote the diversification of energy,still can reduce greenhouse gas emissions.In the aircraft industry at present under the grim situation of emission situation,using bio-jet fuel is also considered as the fundamental way to solve the problem.The process of the hydrodeoxygenation of vegetable oils to bio-jet fuel has the advantages such as high energy density of raw materials and mature technology,which get rapid development.However,the catalysts for hydrodeoxygenation of vegetable oils has many deficiencies such as low active,selective,stable and high hydrogen consumption.In this paper,the load of different metal catalysts were investigated in the fixed bed reactor,and the processing conditions were studied.On these bases,the life test of the catalyst was carried out.Based on the experimental results,it checks and calculates the system which can produce 10000 tons bio-jet fuel composition each year with Aspen Plus in the paper,the economic analysis and profitable analysis is also made.Main conclusions are the following:(1)Compared with the nickel catalysts and ruthenium catalysts,platinum catalysts showed higher catalytic activity and selectivity.1% wt.Pt/Si O2-Zr O2 was screened as catalyst,under the optimal reaction conditions,the liquid alkane yield was 69.30 wt.% and the selectivity of long-chain alkane was 61.46%.With increasing reaction temperature,the yield of liquid alkane increased at the reaction temperature of 573 K to 613 K.But excessively high temperature may bring cracking reaction,thus decreasing the yield of liquid alkane;With increasing reaction pressure,the yield of liquid alkane increased at the reaction pressure of 0.5 MPa to 4.00 MPa.But excessively high pressure may bring cracking reaction,thus decreasing the yield of liquid alkane;With increasing LHSV,the yield of liquid alkane increased.But the yield of liquid alkane decreased when the LHSV was too high;The activity of the catalyst has no obvious decline during the time on stream for 120 h,and the catalyst showed high stability for the reaction.Catalyst samples were characterized,the results show that the active component loss did not happen and the support was of high stability.The catalyst has an activation period at 3h-6h,and the catalyst has high catalytic activity after activation period.(2)Analyses the system which can produce 10000 tons bio-jet fuel composition each year,it was found that the raw materials(vegetable oils,catalysts and hydrogen)cost occupied 80.00% of the product total cost.So the raw material cost is the most important factor of restricting the project's profit ability.The results from financial indicators analysis indicated that the project would not feasible and the project could not be profitable under the present marketing environment.(3)If the raw materials cost is 7036 yuan/ton or the prices of bio-jet fuel is 13200 yuan/tons,the project's static payback period will be 10.48 years,which close to the industry average.