Abstract:

The behavior of non-isothermal thermolysis properties of Tahe atmospheric residue and its sub-fractions (SARA components) were investigated by thermogravimetric analysis. Based on the Sharp differential method, the kinetic parameters, such as maximum rate and its corresponding reaction temperature, conversion and severe cracking temperature range of residue and SARA, as well as the coke formation tendency of SARA were obtained by piecewise fitting. It is found that the coking rate of SARA was in the order of saturates＜aromatics＜resins＜asphaltenes, and the coke formation is mainly from asphaltenes. The weighted coke rate of the SARA component is 4.21 percentage points higher than that of the residue. This indicates that the mixing of SARA is conductive to suppress the coke formation and that saturates promote the coke formation from other groups, while aromatics and resins inhabit the coke formation from asphaltenes and aromatics is better. In the thermal cracking process, the thermal cracking activity is in the order of saturates＞aromatics＞resins＞asphaltenes, and the activation energy of SARA components in low and high temperature range is in the order of saturates＜aromatics＜resins＜asphaltenes, which shows that resins and asphaltenes need more energy during thermal cracking process.

Key words: residue, sub-fractions, thermogravimetric analysis, kinetics