The Use of Chemicals to Break Oil Field Emulsions

Since the early days of oil production, operators have been plagued by emulsified oil. It has been estimated that about 70 per cent of all crude oil is produced in the emulsified form. Before this oil can be transported and refined the emulsified water must be removed. In the early days of the industry, pipe lines would accept oil containing upwards of 5 percent water, while today they will accept only 1 per cent water of basic sediment. Many methods of removing the water and emulsion from this production have been tried with varying degrees of success. In the early days of flush production the "cut oil" or "rolly oil" was flowed or pumped into large earthen pits where it was subjected to treatment by the sun. This slow process produced a top layer of dry or "clean" oil which was decanted periodically and sold. Most of the light fractions were lost in the process but little thought was given to the loss as kerosene was the more important fraction and oil was being produced as fast as it could be dehydrated and sold. Later, some improvements were made by the use of hay tank filters. Centrifuges were tried at some refineries and electrical demulsification was used in the oil fields as well as in refineries. When the operators discovered that lye, washing soda, and strong soap powders such as the old "Gold Dust" rosin soap would break these emulsions, the use of chemicals in oil fields began.