Practical Model for the Induction Period of Heavy Oil during Thermal Reaction

Abstract

The induction period is a significant concept for design and operation of the delayed coking process. To simplify the prediction of the induction period and make it applicable to operational analysis and real-time control of the thermal cracking process, a practical model for the induction period of heavy oil during thermal reaction, which is suitable for the non-isothermal reaction in the industrial conditions, was presented. The development of this model was based on the experimental data of five heavy oils. The model parameters were correlated with microcarbon residue (MCR) of heavy oil to improve the model universality. Furthermore, the validity of correlation between MCR and cracking kinetic parameters was proven. The modelpredicted cracking conversion agrees well with the experimental values. The induction period model was employed to predict the induction period of two feedstocks reported in the literature. Results indicated that the induction period model is available for the thermal reaction of these heavy oils.

New Visual Test Method for the Toluene Insolubles in Oil Products

“…In order to study the influence of the main factors on the test results, the effects of the image number in a single sample pool, the number of sample pools, and the depth of the sample pool on the test results were investigated. The oil sample containing TI was vacuum residue after thermal reaction in a microreactor . The thermal reaction condition was 440 °C, 30 min, and atmospheric pressure.…”

“…The oil sample containing TI was vacuum residue after thermal reaction in a microreactor. 15 The thermal reaction condition was 440 °C, 30 min, and atmospheric pressure. The toluene dilution was used before the oil sample test.…”

“…TI, however, form earlier than the QI. Thus, the TI are an extensively studied coking precursor. − Currently, Soxhlet extraction − and centrifugal separation are both widely used traditional methods to measure the yields of TI in the oil products. However, it was found that the repeatability of the above methods is poor when the yield of TI is less than 1%.…”