Research On The Characteristics Of Petroleum Coke Catalytic Gasification In Different Types Of Reactors

Catalytic gasification technology is a promising use of petroleum coke for it can improve the reactivity of petroleum coke and lower the gasification reaction temperature. Systematically investigating the effect of different catalysts on petroleum coke gasification characteristics as well as its kinetic parameters can guide the design of catalytic gasification process. Previous studies on the catalytic gasification of petroleum coke are almost carried out in fixed bed, but petroleum coke is not suitable feedstock for fixed bed gasifier. Fluidized bed gasification technology has the advantages of a lower gasification temperature, sufficient heat and mass transfer, ability to adapt to wide particle size distribution of raw materials. Catalytic gasification characteristics of petroleum coke in fluidized bed can better reflect the actual catalytic gasification reaction characteristics in fluidized bed gasifier.Firstly effects of different potassium and chlorides on characteristics of petroleum coke gasification were studied in TG. The results show that the gasification activity of petroleum coke could be greatly enhanced by potassium. The addition of catalyst can lower activation energy of gasification reaction.Moreover, potassium-catalyzed gasification of petroleum coke was studied in a fluidized bed and a TG. The potassium carbonate catalytic effect of petroleum coke gasification is very poor in the fluidized bed compared with the result in TG. In the fluidized bed the condensed carbon structure and quite limited pores of petroleum coke resulted in the difficulty of catalyst remaining on the surface of it. Then the active intermediate cannot generate effectively, which leads to the inefficiency of potassium carbonate. Then we put forward pretreatment process to improve the reactivity of catalytic gasification of petroleum coke in fluidized bed.Finally the effect of preheat treatment conditions on surface morphology, functional group, carbon structure of petroleum coke was investigated by SEM/FTIR/Raman spectroscopic. The overall structure of particles remain intact, showed no obvious surface pore structure. The fat ratio increased with the temperature rising. The catalyst can promote the evolution of macrocyclic aromatic ring structure to small aromatic ring structure.