Paper: Cold Treating Of Oilfield Emulsions

In the early years of emulsion treating in the oil field, heat and settling were the only major factors employed. Large open pits frequently provided the settling time and the sun contributed some heat. "Sunning" was a common practice. Some producers employed crude-oil fired retorts and stills to reduce the water content of crude. Large boilers were frequently used to heat tanks of emulsion to facilitate settling of water and emulsion. The large amounts of unresolved emulsion from such operations were usually burned as a means of disposal. With the advent of chemical and electrical treatment, the above procedures were gradually replaced. The use of some heat has continued to the present day but treating temperatures have gradually been reduced with many treating plants operating at ambient temperature. Required settling time has also been drastically reduced over the years. For the most part, the energy required to heat crude as part of the treating process, has been supplied by products produced on the lease so has not been recognized as an expense. Losses in crude gravity and volume, sustained as a result of heating, were judged to be insignificant and difficult to measure and had little or no impact on the value or volume of product sold. In past years, heat may have been a low cost factor in treating. Today, with the shortage of fuel and its increased cost, the economics of the use of heat is worth reevaluating. Before assessing the possibility of reducing heat in oil treating, however, a review of emulsification and oil treating is in order to better understand the role of heat.