Kinetic modeling of Kukersite oil shale pyrolysis with thermal bitumen as an intermediate

摘要

In this work, the kinetics of oil shale pyrolysis was studied in a fixed bed retort with thermal bitumen as an intermediate. Kukersite oil shale samples were tested at temperatures ranging from 300 to 480 degrees C at the constant heating rate of 1 degrees C.min-1. Weights of kerogen, thermal bitumen, shale oil and gases were measured as functions of the final pyrolysis temperature, which were simulated using a first-order reactions in series model under nonisothermal conditions. The obtained kinetic parameters were also proven to accurately describe the experimental results. The proportional factors for products (f(B) = 0.658, f(O1) = 0.183, f(O2) = 0.890, f(G1) = 0.157, f(G2) = 0.106) indicate that kerogen decomposition mainly generates thermal bitumen accounting for 65.8% of total composed kerogen, and that thermal bitumen further degrades and mostly produces shale oil occupying 89.0% of total degraded thermal bitumen. Activation energies and pre-exponential parameters for the two steps are: 126.12 and 192.77 kJ.mol(-1), 1.66 x 10(7) and 1.08 x 10(12) s(-1), respectively.