Theoretical approach to a better understanding of gelation in the framework of petroleum industry: role played by different parameters

Abstract Gelation due to the precipitation of paraffins in petroleum oils is a billion dollar problem in the petroleum industry. The most widely known example in this field is the gelation of crude oil during transportation through sub‐sea pipelines, which in some cases has caused important remediation cost of pipelines blockages. In the case of lubricant oils, gelation is a latent problem from the massive failure in automotive engines that took place in North America during the winter of 1980‐81. In this framework, this work uses a recently developed theoretical survey which has shed light on the physical meaning of the gelation index, that is, the main parameter involved in test ASTM D 5133. This test is commonly used in the petroleum industry for the evaluation of gelation tendency of engine oils at low temperatures. This work analyzes the role played by different parameters (and particularly the induction period and supersaturation ratio) in the theoretical evaluation of the gelation index. In spite of the simplifications used in the theory a qualitative agreement is found when comparing with experimental data, which opens the possibility (after necessary refinements) of a fully predictive theory for nucleation which would be very useful for the petroleum industry.