The amount of asphaltene is usually the minimum portion of crude constituents; however, due to its negative impact on the well performance and the overall efficiency of oil reservoir management, a large number of mostly academic studies are directed toward understanding the asphaltene behavior and mitigation of its deposition in flow processes from reservoir to process facilities. Typically, a small number of these are actual case studies. Among them is the asphaltene deposition in Marrat oil well string. In this particular case, significant amount of valuable field data were gathered for a long period of time under controlled conditions. By carefully reviewing the presented data in the original paper, we concluded that re-analysis of the field observation results, for improved understanding of the asphaltene deposition process, is necessary. By recalling the concept of liquid loading in the gas wells, the reduction of flowing well head pressure is interpreted due to the left asphaltene solid micelles in the well string. Also, we judge that the process of asphaltene deposition in the production tubing is a 'seating and carving' dynamic process, and at a critical thickness, the amount of asphaltene 'cutting' increases which is responsible for further pressure drop in the well tubing. By performing fundamentally simple calculations, the amount of asphaltene 'left' in tubing and the amount of asphaltene 'cutting' are computed. Also the minimum oil flow rate to handle and remove the asphaltene micelles is estimated in the Marrat case. Finally, we propose certain recommendations for future data gathering and optimum handling operation of asphaltene precipitation and deposition in well string.
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