An Experimental Study on Decreasing Acidity of Iranian Crude Oils

Document Type : Research Paper

Authors

Petroleum Refining Research Division, Research Institute of Petroleum Industry (RIPI) Tehran, Iran

Abstract

A survey of the literature shows that the source of total acidity in crude oils is due to naphthenic acids available in their hydrocarbon matrices. On the contrary, our studies show that the emulsion water in crude oil is responsible for the main part of total acid number (TAN), especially for heavy crude oils. In order to avoid metal corrosion in refining facilities and transport lines of crude oil, a special care is needed to control the acidity level of heavy crude oils. In the current work, a new technique based on chemical treatment and centrifugal separation was developed in order to decrease the total acid number of off-spec heavy crude oils. This method was ideally suited for the acid removal of heavy crude oils including water and salt at the level of 0.05-20 vol% and 10-10000 ptb respectively.

Keywords


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