生物质与废塑料共热解的热重教学实验设计OA

[Objective]Biomass conversion and utilization technology is an important component of the curriculum in the major of New Energy Science and Engineering.At present,there are relatively few teaching experiments related to bioenergy in universities,and it is therefore necessary to explore and develop relevant experimental teaching activities.To improve teaching quality and enhance students'practical abilities,an experiment on the co-pyrolysis of biomass and waste plastics was designed,and the corresponding teaching experimental design was developed.[Methods]A thermogravimetric analyzer is an important instrument for studying the relationship between the mass of raw materials and temperature or time.Thermogravimetric analysis is one of the main methods for investigating the co-pyrolysis characteristics and synergistic effects of biomass and waste plastics.It is easy to operate and has a high level of experimental safety.In this study,a thermogravimetric analyzer was employed to design a teaching experiment on the co-pyrolysis of biomass and waste plastics.Waste polypropylene and Nannochloropsis were selected as the experimental raw materials,and the thermal weight loss characteristics of their individual pyrolysis and co-pyrolysis at different mixing ratios were investigated.The characteristic pyrolysis temperatures at different stages were determined.The synergistic effect of co-pyrolysis at different mixing ratios was analyzed by calculating the curve overlap ratio.The influence of different mixing ratios on the pyrolysis kinetic mechanism was discussed,and the reaction models and activation energies under different conditions were clarified.[Results]The results showed that the TG/DTG curves of the mixed samples were not equal to the sum of the TG/DTG curves of the two individual raw materials,although microalgae and plastic dominated different temperature ranges during pyrolysis.When the ratio of plastic to microalgae was 1∶2,1∶1,and 2∶1,the differences between the experimental curves and the calculated curves were relatively large.At these ratios,the overlap ratio values were smaller,indicating that the synergistic interaction between plastic and microalgae was more significant.As the proportion of microalgae increased,the activation energy of co-pyrolysis showed a trend of first decreasing and then increasing.At the ratio of 1∶1,the synergistic effect was strongest,and the activation energy was lowest.The reaction models at different ratios also varied,including nucleation models,diffusion models,reaction order models,and phase boundary reaction models.These results indicate significant changes in the reaction control steps during the co-pyrolysis process.The ratio of raw materials not only influenced the energy required for pyrolysis but also substantially altered the fundamental mechanism of the pyrolysis reaction.[Conclusions]This study introduces the co-pyrolysis technology of biomass and waste plastics as a cutting-edge research topic into undergraduate experimental teaching and achieves close integration between teaching experiments and course content.Through this experiment,students can independently search the literature to understand the latest research frontiers in biomass energy,learn to operate a thermogravimetric analyzer,and conduct co-pyrolysis thermogravimetric experiments under different conditions.Students can also effectively process experimental data and,by combining experimental results with course knowledge and literature analysis,study the kinetics and synergistic effects of co-pyrolysis.This process can improve students'ability to analyze complex problems.