Dissertation > Excellent graduate degree dissertation topics show

Study on Characteristics of Rapid Pyrolysis and Gasification Reactivity of Coal and Petroleum Coke in a DTF Reactor

Author: ChenLu
Tutor: ZhouZhiJie
School: East China University of Science and Technology
Course: Chemical processes
Keywords: drop tube furnace carbon crystallite structure specific surface area modified random pore model diffusion control
CLC: TQ541
Type: Master's thesis
Year: 2012
Downloads: 139
Quote: 2
Read: Download Dissertation

Abstract


In this paper, three coals with different ranks and two petroleum cokes were chosen as experimental material. Their characteristics of rapid pyrolysis were investigated in a drop tube furnace (DTF) reactor. In addition, gasification characteristics of coal char under high temperature, high heating rate were studied in it. The gasification reactivity of rapid pyrolysis char and petroleum coke were examined using TGA (thermogravimetric analyzer), as well as CO2 and steam gasification reaction kinetics of rapid pyrolysis char.Based on analysis of structure and gasification reactivity of rapid pyrolysis char, it is found that there is not good correlation between specific surface area and gasification reactivity of chars, however, the change of gasification reactivity of three chars with increasing pyrolysis temperature is in accordance with the development of carbon crystallite structure of chars which reflect graphitization progress of chars. This proves that the change of carbon crystallite structure of rapid pyrolysis char has a more essential influence on the change of its gasification reactivity. It comes to the same conclusion based on analysis of structure and gasification reactivity of rapid pyrolysis petroleum coke.Modified random pore model can fit various CO2 or steam gasification data well including different coals, pyrolysis temperatures. It remedies shortage of random pore model. Various gasification data could be unified with a master curve when conversion is plotted against normalized time t/t0.5 regardless of coal type, pyrolysis and gasification conditions, which indicates that t0.5 can be used as a reaction index for coal char gasification.Gasification experiment of SF char in DTF shows that, in high temperature diffusion control region, initial gasification rate of char obtained from DTF is about 10 times acquired from TGA. It proves that diffusion effect on gasification of char in DTF is fairly lower than in TGA when gasification temperature is high. Therefore, it can be concluded that DTF reactor is more appropriate to be used for investigating high temperature gasification reactivity of coal char.

Related Dissertations

  1. Controlied Synthesis of β-SiC with Different Morphologies and Catalytic Application,O643.36
  2. Synthesis and Properties of Cyclotriphosphazene Derivatives with Tetrazole and Oxadiazole Groups,O627.51
  3. Coal Particle Ignition Temperatures and Combustion Characteristics of Different Rank Coals in O2/CO2 Environments,TK16
  4. The Analysis of Safty and Economy of Idonesia Coal Mixed Burn in Coal-fired Boiler,TK227.1
  5. Preparation of high surface area activated carbon , forming and preliminary application,TQ424.1
  6. Key Technologies Research of Electric Furnace Slag Used in the Cement and Concrete,TU528.2
  7. Estimation Model of Asphalt Content for SAMPAVE Stress Absorbing Layer Mixture,U414
  8. Study on Process Analysis and Oil Absorptive Properties of Kaolin Modified by Acid and Alkali,TD985
  9. Preparation and storage of the electrode material for electrochemical capacitors electrical properties,TM53
  10. Study on the Manufacturing of Concrete Aggregates by Using Desert Sand,TU528
  11. Capacitance adsorption studies concentrated seawater,P746
  12. Study on Synthesis, Character and Properties of Carbon Nanomaterials,TB383.1
  13. Low-Temperature Synthesis and Properties of Porous Boron Nitride Nanomaterials,TB383.1
  14. Low - temperature polycrystalline lithium hydride hydrolysis behavior research,O614.111
  15. Preparation of a Carbon-based Solid Acid Catalyst with Hign Specific Surface Area by Biomass Wood Powder,O643.36
  16. Mesoporous Al_2O_3, AlF_3 Pd/Al_2O_3 catalyst preparation and properties of catalytic combustion of methane,O643.36
  17. Study on Cr-based Catalysts for Vapor-phase Fluorination to Synthesis CF4 and Preparation of β-AlF3 with High Surface Area,O643.32
  18. Study on the Preparation and Gas Sensing of SnO2 Nano-material,TN304.21
  19. Preparation and characterization of solid solution of cerium iron,O614
  20. Study on Decomposition Behavior of Magnesium Hydrate,TQ132.2

CLC: > Industrial Technology > Chemical Industry > Coal gasification industry > Gasification theory ( combustible gas,gas )
© 2012 www.DissertationTopic.Net  Mobile