Evaluation of the Shutdown Time of Subsea Pipeline for Oil Transportation

D. Maciel[1], N. Bouchonneau[1]
[1]Universidade Federal de Pernambuco, Recife, Pernambuco, Brazil

The maintenance plan or rush-to-repair of a subsea pipeline for oil transport may result in the shutdown of the line, in other words, may stop the flow of fluid. During the shutdown, the temperature of the oil tends to decrease continuously, and the heavy molecules tend to crystallize and suspend in the oil, which increase the viscosity of the oil, and even form a paraffinic compound or freeze the production line. This work was carried out in order to analyze the temperature distribution in an insulated pipeline during its restart (transient state), work (steady state) and shutdown, and estimate the time required to reach the critical temperatures of approximately 40 and 25 ÂșC during the shutdown.