Study On Co-pyrolysis Characteristics Of Platanus And Bituminous Coal In A Tube Furnace

As an important driving force to promote the rapid development of national economy,the reserve,development and effective utilization of energy have become the standard to measure whether a country is strong or not.Fossil energy is still in the forefront of the global energy consumption structure,while the conventional way of fossil energy consumption is mainly combustion,which not only causes great environmental pollution,but also has low thermal efficiency due to the shortcomings of energy itself.Therefore,how to efficiently and cleanly use fossil energy,especially coal resources,has become an important task of current economic development.Biomass resources are very rich,and biomass energy is one of the most important new energy sources in the world.With mature technology and wide application,the co-pyrolysis of biomass with coal can not only improve the conversion rate of coal,reduce the production cost,but also make effective use of natural resources.In this paper,the co-pyrolysis characteristics under different conditions were explored through the tube furnace pyrolysis experiments on platanus and bituminous coal,and the industrial utilization of biomass and coal co-pyrolysis will be provided with theoretical and data support.In this paper,a horizontal tube furnace was firstly used to perform rapid pyrolysis experiments at 500℃ on three kinds of platanus materials,three kinds of bituminous coal and their mixtures.Also,the solid and liquid product structure groups of platanus and bituminous coal pyrolysis were analyzed separately.Through the comparison of actual experiment production yield and theoretical calculation of yield,the synergistic effect of pyrolysis of platanus and bituminous coal was discussed.Infrared spectrum analysis and nuclear magnetic resonance spectroscopy analysis of the products in the pyrolysis of platanus and bituminous coal were performed.It was found that the co-pyrolysis of platanus leaves and bituminous coal 09 produced a synergistic effect to promote the tar yield,while the other mixed samples all produced an inhibitory effect.The etheric C-O-C,phenolic C-O and ester C-O-O-C in co-pyrolysis semi-coke decreased compared to the case of pyrolysis alone,while the methylene branched chains in hydrocarbons increased.The contents of polycyclic aromatic hydrocarbons,monocyclic aromatic hydrocarbons and aliphatic compounds in co-pyrolysis tar vary,but the contents of aldehyde and carboxyl groups are lower than the theoretical values,indicating that the co-pyrolysis reaction effectively reduces the number of hydrogen protons of aldehyde and carboxyl groups.In order to deeply explore the impact of different factors on the co-pyrolysis of platanus and bituminous coal,the influence of CO2 on pyrolysis under different reaction atmosphere,the effect of temperature by using thermogravimetric analyzer and catalytic reaction effect by adding catalysts were explored.Elemental analysis,pore structure and specific surface area analysis(BET)and infrared analysis(FT-IR)were used for solid products,while nuclear magnetic resonance spectroscopy(NMR)was mainly used for liquid products.The results showed that CO2 improved the pore size,pore volume and BET surface area of the solid products,and promoted the increase of oxygen-containing aromatic hydrocarbons in the tar.With the increase of temperature,the solid yield of platanus and bituminous coal gradually decreased.In the range of 400-600℃,the tar yield of platanus pyrolysis alone gradually increased with the increase of temperature,while that of bituminous coal increased first and then decreased.The addition of catalyst Ca O and ZSM-5 effectively promoted the decomposition of tar and increased the content of gas products.At the same time,the content of aromatic and aliphatic methoxy hydrogen protons increased to different degrees,while that of oxygen-containing aromatic compounds and methoxy aliphatic compounds decreased.Finally,the model compounds were used to explore the co-pyrolysis of biomass and coal,and the lignin model compounds guaiacol and phenoxyethylbenzene were co-pyrolyzed with bituminous coal.It was found that the solid product yield,structure and composition changed relatively Small,the addition of phenoxyethylbenzene can effectively improve the liquid yield of pyrolysis of bituminous coal,while guaiacol exhibits stronger gas generation with pyrolysis of bituminous coal.The co-pyrolysis tar contains more lignin model compounds,and only a small part participates in the pyrolysis reaction.Through the co-pyrolysis of simple model compounds of coal,anthracene and naphthalene,and sycamore,it was found that the yield,structure and composition of the solid product did not change much,but the pore structure of the pyrolysis particles was improved,and the specific surface area and total pore volume got promoted.A small part of the coal model compounds participated in the co-pyrolysis reaction,and some new compounds were produced in the liquid product.